Browse Source
* master: (113 commits) Remove esprima-fb and use Syntax from jstransform Update React.renderToString argument type in docs [traverseAllChildren] fix out-of-scope var use. Use double quote for transformed `displayName` and `data-*` Remove unrelated comment Fix typo in If/Else JSX doc. Cleanup a couple unused variables Use dump cache and remove factory from ReactElement-test Update deprecated propTypes Bring in jsfiddle integration script, add harmony Extending period in which click events are ignored React.renderComponent --> React.render Followup fix for React.PropTypes.node Add comma for readability in tutorial Drop internal uses of .type on the class Drop Legacy Factories Around Classes Drop ReactDOM from internal DOM extensions Added comma to increase readability. Add 0.12 starter kit Change the date and the link url to match the proper roundup ... Conflicts: docs/docs/02.1-jsx-in-depth.mdmain
Pedro Nauck
10 years ago
70 changed files with 1582 additions and 518 deletions
@ -1,19 +1,14 @@ |
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/** |
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* @jsx React.DOM |
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*/ |
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var HELLO_COMPONENT = ` |
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var HelloMessage = React.createClass({ |
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render: function() { |
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return <div>Hello {this.props.name}</div>; |
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} |
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}); |
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|
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var HELLO_COMPONENT = "\ |
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/** @jsx React.DOM */\n\ |
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var HelloMessage = React.createClass({\n\ |
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render: function() {\n\ |
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return <div>Hello {this.props.name}</div>;\n\ |
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}\n\ |
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});\n\ |
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\n\ |
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React.renderComponent(<HelloMessage name=\"John\" />, mountNode);\ |
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"; |
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React.render(<HelloMessage name="John" />, mountNode); |
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`;
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|
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React.renderComponent( |
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React.render( |
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<ReactPlayground codeText={HELLO_COMPONENT} />, |
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document.getElementById('helloExample') |
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); |
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|
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@ -1,43 +1,37 @@ |
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/** |
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* @jsx React.DOM |
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*/ |
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var MARKDOWN_COMPONENT = ` |
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var converter = new Showdown.converter(); |
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|
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var MARKDOWN_COMPONENT = "\ |
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/** @jsx React.DOM */\n\ |
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\n\ |
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var converter = new Showdown.converter();\n\ |
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\n\ |
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var MarkdownEditor = React.createClass({\n\ |
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getInitialState: function() {\n\ |
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return {value: 'Type some *markdown* here!'};\n\ |
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},\n\ |
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handleChange: function() {\n\ |
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this.setState({value: this.refs.textarea.getDOMNode().value});\n\ |
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},\n\ |
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render: function() {\n\ |
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return (\n\ |
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<div className=\"MarkdownEditor\">\n\ |
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<h3>Input</h3>\n\ |
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<textarea\n\ |
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onChange={this.handleChange}\n\ |
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ref=\"textarea\"\n\ |
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defaultValue={this.state.value} />\n\ |
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<h3>Output</h3>\n\ |
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<div\n\ |
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className=\"content\"\n\ |
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dangerouslySetInnerHTML={{\n\ |
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__html: converter.makeHtml(this.state.value)\n\ |
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}}\n\ |
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/>\n\ |
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</div>\n\ |
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);\n\ |
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}\n\ |
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});\n\ |
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\n\ |
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React.renderComponent(<MarkdownEditor />, mountNode);\ |
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"; |
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var MarkdownEditor = React.createClass({ |
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getInitialState: function() { |
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return {value: 'Type some *markdown* here!'}; |
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}, |
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handleChange: function() { |
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this.setState({value: this.refs.textarea.getDOMNode().value}); |
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}, |
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render: function() { |
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return ( |
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<div className="MarkdownEditor"> |
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<h3>Input</h3> |
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<textarea |
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onChange={this.handleChange} |
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ref="textarea" |
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defaultValue={this.state.value} /> |
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<h3>Output</h3> |
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<div |
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className="content" |
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dangerouslySetInnerHTML={{ |
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__html: converter.makeHtml(this.state.value) |
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}} |
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/> |
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</div> |
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); |
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} |
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}); |
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|
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React.renderComponent( |
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React.render(<MarkdownEditor />, mountNode); |
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`;
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|
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React.render( |
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<ReactPlayground codeText={MARKDOWN_COMPONENT} />, |
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document.getElementById('markdownExample') |
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); |
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|
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@ -1,33 +1,28 @@ |
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/** |
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* @jsx React.DOM |
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*/ |
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var TIMER_COMPONENT = ` |
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var Timer = React.createClass({ |
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getInitialState: function() { |
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return {secondsElapsed: 0}; |
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}, |
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tick: function() { |
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this.setState({secondsElapsed: this.state.secondsElapsed + 1}); |
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}, |
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componentDidMount: function() { |
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this.interval = setInterval(this.tick, 1000); |
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}, |
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componentWillUnmount: function() { |
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clearInterval(this.interval); |
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}, |
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render: function() { |
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return ( |
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<div>Seconds Elapsed: {this.state.secondsElapsed}</div> |
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); |
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} |
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}); |
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|
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var TIMER_COMPONENT = "\ |
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/** @jsx React.DOM */\n\ |
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var Timer = React.createClass({\n\ |
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getInitialState: function() {\n\ |
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return {secondsElapsed: 0};\n\ |
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},\n\ |
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tick: function() {\n\ |
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this.setState({secondsElapsed: this.state.secondsElapsed + 1});\n\ |
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},\n\ |
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componentDidMount: function() {\n\ |
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this.interval = setInterval(this.tick, 1000);\n\ |
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},\n\ |
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componentWillUnmount: function() {\n\ |
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clearInterval(this.interval);\n\ |
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},\n\ |
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render: function() {\n\ |
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return (\n\ |
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<div>Seconds Elapsed: {this.state.secondsElapsed}</div>\n\ |
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);\n\ |
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}\n\ |
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});\n\ |
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\n\ |
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React.renderComponent(<Timer />, mountNode);\ |
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"; |
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React.render(<Timer />, mountNode); |
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`;
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React.renderComponent( |
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React.render( |
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<ReactPlayground codeText={TIMER_COMPONENT} />, |
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document.getElementById('timerExample') |
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); |
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@ -1,47 +1,43 @@ |
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/** |
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* @jsx React.DOM |
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*/ |
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var TODO_COMPONENT = ` |
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var TodoList = React.createClass({ |
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render: function() { |
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var createItem = function(itemText) { |
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return <li>{itemText}</li>; |
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}; |
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return <ul>{this.props.items.map(createItem)}</ul>; |
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} |
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}); |
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var TodoApp = React.createClass({ |
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getInitialState: function() { |
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return {items: [], text: ''}; |
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}, |
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onChange: function(e) { |
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this.setState({text: e.target.value}); |
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}, |
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handleSubmit: function(e) { |
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e.preventDefault(); |
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var nextItems = this.state.items.concat([this.state.text]); |
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var nextText = ''; |
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this.setState({items: nextItems, text: nextText}); |
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}, |
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render: function() { |
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return ( |
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<div> |
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<h3>TODO</h3> |
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<TodoList items={this.state.items} /> |
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<form onSubmit={this.handleSubmit}> |
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<input onChange={this.onChange} value={this.state.text} /> |
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<button>{'Add #' + (this.state.items.length + 1)}</button> |
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</form> |
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</div> |
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); |
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} |
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}); |
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|
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var TODO_COMPONENT = "\ |
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/** @jsx React.DOM */\n\ |
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var TodoList = React.createClass({\n\ |
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render: function() {\n\ |
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var createItem = function(itemText) {\n\ |
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return <li>{itemText}</li>;\n\ |
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};\n\ |
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return <ul>{this.props.items.map(createItem)}</ul>;\n\ |
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}\n\ |
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});\n\ |
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var TodoApp = React.createClass({\n\ |
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getInitialState: function() {\n\ |
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return {items: [], text: ''};\n\ |
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},\n\ |
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onChange: function(e) {\n\ |
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this.setState({text: e.target.value});\n\ |
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},\n\ |
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handleSubmit: function(e) {\n\ |
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e.preventDefault();\n\ |
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var nextItems = this.state.items.concat([this.state.text]);\n\ |
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var nextText = '';\n\ |
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this.setState({items: nextItems, text: nextText});\n\ |
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},\n\ |
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render: function() {\n\ |
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return (\n\ |
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<div>\n\ |
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<h3>TODO</h3>\n\ |
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<TodoList items={this.state.items} />\n\ |
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<form onSubmit={this.handleSubmit}>\n\ |
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<input onChange={this.onChange} value={this.state.text} />\n\ |
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<button>{'Add #' + (this.state.items.length + 1)}</button>\n\ |
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</form>\n\ |
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</div>\n\ |
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);\n\ |
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}\n\ |
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});\n\ |
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React.renderComponent(<TodoApp />, mountNode);\ |
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"; |
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React.render(<TodoApp />, mountNode); |
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`;
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|
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React.renderComponent( |
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React.render( |
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<ReactPlayground codeText={TODO_COMPONENT} />, |
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document.getElementById('todoExample') |
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); |
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|
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@ -0,0 +1,11 @@ |
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(function() { |
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var tag = document.querySelector( |
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'script[type="application/javascript;version=1.7"]' |
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); |
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if (!tag || tag.textContent.indexOf('window.onload=function(){') !== -1) { |
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alert('Bad JSFiddle configuration, please fork the original React JSFiddle'); |
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} |
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tag.setAttribute('type', 'text/jsx;harmony=true'); |
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tag.textContent = tag.textContent.replace(/^\/\/<!\[CDATA\[/, ''); |
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})(); |
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|
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@ -0,0 +1,46 @@ |
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--- |
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title: React v0.11.2 |
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author: Paul O’Shannessy |
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--- |
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|
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Today we're releasing React v0.11.2 to add a few small features. |
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We're adding support for two more DOM elements, `<dialog>` and `<picture>`, as well as the associated attributes needed to use these elements: `open`, `media`, and `sizes`. While not all browsers support these natively, some of our cutting edge users want to make use of them, so we're making them available to everybody. |
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We're also doing some work to prepare for v0.12 and improve compatibility between the versions. To do this we are replacing `React.createDescriptor` with `React.createElement`. `createDescriptor` will continue to work with a warning and will be gone in v0.12. Chances are that this won't affect anybody. |
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|
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And lastly, on the heels of announcing Flow at [@Scale](http://atscaleconference.com/) yesterday, we're adding the ability to strip TypeScript-like type annotations as part of the `jsx` transform. To use, simply use the `--strip-types` flag on the command line, or set `stripTypes` in the `options` object when calling the API. We'll be talking about Flow more in the coming months. But for now, it's helpful to know that it is a flow-sensitive JavaScript type checker we will be open sourcing soon. |
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The release is available for download from the CDN: |
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* **React** |
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Dev build with warnings: <http://fb.me/react-0.11.2.js> |
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Minified build for production: <http://fb.me/react-0.11.2.min.js> |
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* **React with Add-Ons** |
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Dev build with warnings: <http://fb.me/react-with-addons-0.11.2.js> |
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Minified build for production: <http://fb.me/react-with-addons-0.11.2.min.js> |
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* **In-Browser JSX transformer** |
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<http://fb.me/JSXTransformer-0.11.2.js> |
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We've also published version `0.11.2` of the `react` and `react-tools` packages on npm and the `react` package on bower. |
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Please try these builds out and [file an issue on GitHub](https://github.com/facebook/react/issues/new) if you see anything awry. |
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|
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### React Core |
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|
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#### New Features |
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* Added support for `<dialog>` element and associated `open` attribute |
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* Added support for `<picture>` element and associated `media` and `sizes` attributes |
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* Added `React.createElement` API in preparation for React v0.12 |
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* `React.createDescriptor` has been deprecated as a result |
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### JSX |
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* `<picture>` is now parsed into `React.DOM.picture` |
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### React Tools |
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* Update `esprima` and `jstransform` for correctness fixes |
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* The `jsx` executable now exposes a `--strip-types` flag which can be used to remove TypeScript-like type annotations |
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* This option is also exposed to `require('react-tools').transform` as `stripTypes` |
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@ -0,0 +1,222 @@ |
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--- |
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title: "Introducing React Elements" |
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author: Sebastian Markbåge |
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redirect_from: "blog/2014/10/14/introducting-react-elements.html" |
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--- |
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|
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The upcoming React 0.12 tweaks some APIs to get us close to the final 1.0 API. This release is all about setting us up for making the `ReactElement` type really FAST, [jest unit testing](http://facebook.github.io/jest/) easier, making classes simpler (in preparation for ES6 classes) and better integration with third-party languages! |
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If you currently use JSX everywhere, you don't really have to do anything to get these benefits! The updated transformer will do it for you. |
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If you can't or don't want to use JSX, then please insert some hints for us. Add a `React.createFactory` call around your imported class when you require it: |
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```javascript |
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var MyComponent = React.createFactory(require('MyComponent')); |
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``` |
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Everything is backwards compatible for now, and as always React will provide you with descriptive console messaging to help you upgrade. |
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`ReactElement` is the primary API of React. Making it faster has shown to give us several times faster renders on common benchmarks. The API tweaks in this release helps us get there. |
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Continue reading if you want all the nitty gritty details... |
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## New Terminology |
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We wanted to make it easier for new users to see the parallel with the DOM (and why React is different). To align our terminology we now use the term `ReactElement` instead of _descriptor_. Likewise, we use the term `ReactNode` instead of _renderable_. |
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[See the full React terminology guide.](https://gist.github.com/sebmarkbage/fcb1b6ab493b0c77d589) |
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## Creating a ReactElement |
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We now expose an external API for programmatically creating a `ReactElement` object. |
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```javascript |
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var reactElement = React.createElement(type, props, children); |
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``` |
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The `type` argument is either a string (HTML tag) or a class. It's a description of what tag/class is going to be rendered and what props it will contain. You can also create factory functions for specific types. This basically just provides the type argument for you: |
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```javascript |
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var div = React.createFactory('div'); |
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var reactDivElement = div(props, children); |
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``` |
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## Deprecated: Auto-generated Factories |
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Imagine if `React.createClass` was just a plain JavaScript class. If you call a class as a plain function you would call the component's constructor to create a Component instance, not a `ReactElement`: |
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```javascript |
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new MyComponent(); // Component, not ReactElement |
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``` |
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React 0.11 gave you a factory function for free when you called `React.createClass`. This wrapped your internal class and then returned a `ReactElement` factory function for you. |
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```javascript |
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var MyComponent = React.createFactory( |
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class { |
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render() { |
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... |
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} |
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} |
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); |
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``` |
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In future versions of React, we want to be able to support pure classes without any special React dependencies. To prepare for that we're [deprecating the auto-generated factory](https://gist.github.com/sebmarkbage/d7bce729f38730399d28). |
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This is the biggest change to 0.12. Don't worry though. This functionality continues to work the same for this release, it just warns you if you're using a deprecated API. That way you can upgrade piece-by-piece instead of everything at once. |
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## Upgrading to 0.12 |
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### React With JSX |
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If you use the React specific [JSX](http://facebook.github.io/jsx/) transform, the upgrade path is simple. Just make sure you have React in scope. |
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```javascript |
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// If you use node/browserify modules make sure |
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// that you require React into scope. |
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var React = require('react'); |
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``` |
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React's JSX will create the `ReactElement` for you. You can continue to use JSX with regular classes: |
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```javascript |
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var MyComponent = React.createClass(...); |
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var MyOtherComponent = React.createClass({ |
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render: function() { |
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return <MyComponent prop="value" />; |
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} |
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}); |
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``` |
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|
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*NOTE: React's JSX will not call arbitrary functions in future releases. This restriction is introduced so that it's easier to reason about the output of JSX by both the reader of your code and optimizing compilers. The JSX syntax is not tied to React. Just the transpiler. You can still use [the JSX spec](http://facebook.github.io/jsx/) with a different transpiler for custom purposes.* |
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|
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### React Without JSX |
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If you don't use JSX and just call components as functions, you will need to explicitly create a factory before calling it: |
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|
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```javascript |
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var MyComponentClass = React.createClass(...); |
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|
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var MyComponent = React.createFactory(MyComponentClass); // New step |
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|
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var MyOtherComponent = React.createClass({ |
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render: function() { |
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return MyComponent({ prop: 'value' }); |
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} |
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}); |
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``` |
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|
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If you're using a module system, the recommended solution is to export the class and create the factory on the requiring side. |
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|
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Your class creation is done just like before: |
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|
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```javascript |
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// MyComponent.js |
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var React = require('react'); |
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var MyComponent = React.createClass(...); |
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module.exports = MyComponent; |
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``` |
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|
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The other side uses `React.createFactory` after `require`ing the component class: |
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|
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```javascript |
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// MyOtherComponent.js |
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var React = require('react'); |
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// All you have to do to upgrade is wrap your requires like this: |
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var MyComponent = React.createFactory(require('MyComponent')); |
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|
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var MyOtherComponent = React.createClass({ |
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render: function() { |
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return MyComponent({ prop: 'value' }); |
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} |
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}); |
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|
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module.exports = MyOtherComponent; |
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``` |
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|
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You ONLY have to do this for custom classes. React still has built-in factories for common HTML elements. |
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|
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```javascript |
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var MyDOMComponent = React.createClass({ |
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render: function() { |
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return React.DOM.div({ className: 'foo' }); // still ok |
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} |
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}); |
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``` |
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|
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We realize that this is noisy. At least it's on the top of the file (out of sight, out of mind). This a tradeoff we had to make to get [the other benefits](https://gist.github.com/sebmarkbage/d7bce729f38730399d28) that this model unlocks. |
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|
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### Anti-Pattern: Exporting Factories |
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|
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If you have an isolated project that only you use, then you could create a helper that creates both the class and the factory at once: |
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|
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```javascript |
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// Anti-pattern - Please, don't use |
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function createClass(spec) { |
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return React.createFactory(React.createClass(spec)); |
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} |
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``` |
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|
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This makes your components incompatible with jest testing, consumers using JSX, third-party languages that implement their own optimized `ReactElement` creation, etc. |
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|
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It also encourages you to put more logic into these helper functions. Something that another language, a compiler or a reader of your code couldn't reason about. |
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|
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To fit into the React ecosystem we recommend that you always export pure classes from your shared modules and let the consumer decide the best strategy for generating `ReactElement`s. |
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|
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## Third-party Languages |
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|
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The signature of a `ReactElement` is something like this: |
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|
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```javascript |
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{ |
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type : string | class, |
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props : { children, className, etc. }, |
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key : string | boolean | number | null, |
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ref : string | null |
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} |
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``` |
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|
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Languages with static typing that don't need validation (e.g. [Om in ClojureScript](https://github.com/swannodette/om)), and production level compilers will be able to generate these objects inline instead of going through the validation step. This optimization will allow significant performance improvements in React. |
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|
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|
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## Your Thoughts and Ideas |
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|
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We'd love to hear your feedback on this API and your preferred style. A plausible alternative could be to directly inline objects instead of creating factory functions: |
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|
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```javascript |
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// MyOtherComponent.js |
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var React = require('react'); |
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var MyComponent = require('MyComponent'); |
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|
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var MyOtherComponent = React.createClass({ |
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render: function() { |
|||
return { type: MyComponent, props: { prop: 'value' } }; |
|||
} |
|||
}); |
|||
|
|||
module.exports = MyOtherComponent; |
|||
``` |
|||
|
|||
This moves the noise down into the render method though. It also doesn't provide a hook for dynamic validation/type checking so you'll need some other way to verify that it's safe. |
|||
|
|||
*NOTE: This won't work in this version of React because it's conflicting with other legacy APIs that we're deprecating. (We temporarily add a `element._isReactElement = true` marker on the object.)* |
|||
|
|||
|
|||
## The Next Step: ES6 Classes |
|||
|
|||
After 0.12 we'll begin work on moving to ES6 classes. We will still support `React.createClass` as a backwards compatible API. If you use an ES6 transpiler you will be able to declare your components like this: |
|||
|
|||
```javascript |
|||
export class MyComponent { |
|||
render() { |
|||
... |
|||
} |
|||
}; |
|||
``` |
|||
|
|||
This upcoming release is a stepping stone to make it as easy as this. Thanks for your support. |
|||
@ -0,0 +1,150 @@ |
|||
--- |
|||
title: "React v0.12 RC" |
|||
author: Sebastian Markbåge |
|||
--- |
|||
|
|||
We are finally ready to share the work we've been doing over the past couple months. A lot has gone into this and we want to make sure we iron out any potential issues before we make this final. So, we're shipping a Release Candidate for React v0.12 today. If you get a chance, please give it a try and report any issues you find! A full changelog will accompany the final release but we've highlighted the interesting and breaking changes below. |
|||
|
|||
|
|||
The release candidate is available for download: |
|||
|
|||
* **React** |
|||
Dev build with warnings: <http://fb.me/react-0.12.0-rc1.js> |
|||
Minified build for production: <http://fb.me/react-0.12.0-rc1.min.js> |
|||
* **React with Add-Ons** |
|||
Dev build with warnings: <http://fb.me/react-with-addons-0.12.0-rc1.js> |
|||
Minified build for production: <http://fb.me/react-with-addons-0.12.0-rc1.min.js> |
|||
* **In-Browser JSX transformer** |
|||
<http://fb.me/JSXTransformer-0.12.0-rc1.js> |
|||
|
|||
We've also published version `0.12.0-rc1` of the `react` and `react-tools` packages on npm and the `react` package on bower. |
|||
|
|||
|
|||
## React Elements |
|||
|
|||
The biggest conceptual change we made in v0.12 is the move to React Elements. [We talked about this topic in depth earlier this week](/react/blog/2014/10/14/introducting-react-elements.html). If you haven't already, you should read up on the exciting changes in there! |
|||
|
|||
|
|||
## JSX Changes |
|||
|
|||
Earlier this year we decided to write [a specification for JSX](http://facebook.github.io/jsx/). This has allowed us to make some changes focused on the React specific JSX and still allow others to innovate in the same space. |
|||
|
|||
|
|||
### The `@jsx` Pragma is Gone! |
|||
|
|||
We have wanted to do this since before we even open sourced React. No more `/** @jsx React.DOM */`!. The React specific JSX transform assumes you have `React` in scope (which had to be true before anyway). |
|||
|
|||
`JSXTransformer` and `react-tools` have both been updated to account for this. |
|||
|
|||
|
|||
### JSX for Function Calls is No Longer Supported |
|||
|
|||
The React specific JSX transform no longer transforms to function calls. Instead we use `React.createElement` and pass it arguments. This allows us to make optimizations and better support React as a compile target for things like Om. Read more in the [React Elements introduction](/react/blog/2014/10/14/introducting-react-elements.html). |
|||
|
|||
The result of this change is that we will no longer support arbitrary function calls. We understand that the ability to do was was a convenient shortcut for many people but we believe the gains will be worth it. |
|||
|
|||
|
|||
### JSX Lower-case Convention |
|||
|
|||
We used to have a whitelist of HTML tags that got special treatment in JSX. However as new HTML tags got added to the spec, or we added support for more SVG tags, we had to go update our whitelist. Additionally, there was ambiguity about the behavior. There was always the chance that something new added to the tag list would result in breaking your code. For example: |
|||
|
|||
```javascript |
|||
return <component />; |
|||
``` |
|||
|
|||
Is `component` an existing HTML tag? What if it becomes one? |
|||
|
|||
To address this, we decided on a convention: __All JSX tags that start with a lower-case letter or contain a dash are treated as HTML.__ |
|||
|
|||
This means that you no longer have to wait for us to upgrade JSX to use new tags. This also introduces the possibility to consume custom elements (Web Components) - although custom attributes are not yet fully supported. |
|||
|
|||
Currently we still use the whitelist as a sanity check. The transform will fail when it encounters an unknown tag. This allows you to update your code without hitting errors in production. |
|||
|
|||
In addition, the HTML tags are converted to strings instead of using `React.DOM` directly. `<div/>` becomes `React.createElement('div')` instead of `React.DOM.div()`. |
|||
|
|||
|
|||
### JSX Spread Attributes |
|||
|
|||
Previously there wasn't a way to for you to pass a dynamic or unknown set of properties through JSX. This is now possible using the spread `...` operator. |
|||
|
|||
```javascript |
|||
var myProps = { a: 1, b: 2 }; |
|||
return <MyComponent {...myProps} />; |
|||
``` |
|||
|
|||
This merges the properties of the object onto the props of `MyComponent`. |
|||
|
|||
[Read More About Spread Attributes](https://gist.github.com/sebmarkbage/07bbe37bc42b6d4aef81) |
|||
|
|||
If you used to use plain function calls to pass arbitrary props objects... |
|||
|
|||
```javascript |
|||
return MyComponent(myProps); |
|||
``` |
|||
|
|||
You can now switch to using Spread Attributes instead: |
|||
|
|||
```javascript |
|||
return <MyComponent {...myProps} />; |
|||
``` |
|||
|
|||
|
|||
## Breaking Change: `key` and `ref` Removed From `this.props` |
|||
|
|||
The props `key` and `ref` were already reserved property names. This turned out to be difficult to explicitly statically type since any object can accept these extra props. It also screws up JIT optimizations of React internals in modern VMs. |
|||
|
|||
These are concepts that React manages from outside the Component before it even gets created so it shouldn't be part of the props. |
|||
|
|||
We made this distinction clearer by moving them off the props object and onto the `ReactElement` itself. This means that you need to rename: |
|||
|
|||
`someElement.props.key` -> `someElement.key` |
|||
|
|||
You can no longer access `this.props.ref` and `this.props.key` from inside the Component instance itself. So you need to use a different name for those props. |
|||
|
|||
You do NOT need to change the way to define `key` and `ref`, only if you need to read it. E.g. `<div key="my-key" />` and `div({ key: 'my-key' })` still works. |
|||
|
|||
|
|||
## Breaking Change: Default Props Resolution |
|||
|
|||
This is a subtle difference but `defaultProps` are now resolved at `ReactElement` creation time instead of when it's mounted. This is means that we can avoid allocating an extra object for the resolved props. |
|||
|
|||
You will primarily see this breaking if you're also using `transferPropsTo`. |
|||
|
|||
|
|||
## Deprecated: transferPropsTo |
|||
|
|||
`transferPropsTo` is deprecated in v0.12 and will be removed in v0.13. This helper function was a bit magical. It auto-merged a certain whitelist of properties and excluded others. It was also transferring too many properties. This meant that we have to keep a whitelist of valid HTML attributes in the React runtime. It also means that we can't catch typos on props. |
|||
|
|||
Our suggested solution is to use the Spread Attributes. |
|||
|
|||
```javascript |
|||
return <div {...this.props} />; |
|||
``` |
|||
|
|||
Or, just if you're not using JSX: |
|||
|
|||
```javascript |
|||
return div(this.props); |
|||
``` |
|||
|
|||
Although to avoid passing too many props down, you'll probably want to use something like ES7 rest properties. [Read more about upgrading from transferPropsTo](https://gist.github.com/sebmarkbage/a6e220b7097eb3c79ab7). |
|||
|
|||
|
|||
## Deprecated: Returning `false` in Event Handlers |
|||
|
|||
It used to be possible to return `false` from event handlers to preventDefault. We did this because this works in most browsers. This is a confusing API and we might want to use the return value for something else. Therefore, this is deprecated. Use `event.preventDefault()` instead. |
|||
|
|||
|
|||
## Renamed APIs |
|||
|
|||
As part of the [new React terminology](https://gist.github.com/sebmarkbage/fcb1b6ab493b0c77d589) we aliased some existing APIs to use the new naming convention: |
|||
|
|||
- `React.renderComponent` -> `React.render` |
|||
- `React.renderComponentToString` -> `React.renderToString` |
|||
- `React.renderComponentToStaticMarkup` -> `React.renderToStaticMarkup` |
|||
- `React.isValidComponent` -> `React.isValidElement` |
|||
- `React.PropTypes.component` -> `React.PropTypes.element` |
|||
- `React.PropTypes.renderable` -> `React.PropTypes.node` |
|||
|
|||
The older APIs will log a warning but work the same. They will be removed in v0.13. |
|||
|
|||
@ -0,0 +1,152 @@ |
|||
--- |
|||
title: "Community Round-up #23" |
|||
layout: post |
|||
author: Lou Husson |
|||
--- |
|||
|
|||
This round-up is a special edition on [Flux](http://facebook.github.io/flux/). If you expect to see diagrams showing arrows that all point in the same direction, you won't be disappointed! |
|||
|
|||
## React And Flux at ForwardJS |
|||
|
|||
Facebook engineers [Jing Chen](https://github.com/jingc) and [Bill Fisher](https://github.com/fisherwebdev) gave a talk about Flux and React at [ForwardJS](http://forwardjs.com/), and how using an application architecture with a unidirectional data flow helped solve recurring bugs. |
|||
|
|||
<iframe width="650" height="315" src="//www.youtube.com/embed/i__969noyAM" frameborder="0" allowfullscreen></iframe> |
|||
|
|||
# Yahoo |
|||
|
|||
Yahoo is converting Yahoo Mail to React and Flux and in the process, they open sourced several components. This will help you get an isomorphic application up and running. |
|||
|
|||
- [Flux Router Component](https://github.com/yahoo/flux-router-component) |
|||
- [Dispatchr](https://github.com/yahoo/dispatchr) |
|||
- [Fetchr](https://github.com/yahoo/fetchr) |
|||
- [Flux Examples](https://github.com/yahoo/flux-examples) |
|||
|
|||
|
|||
## Reflux |
|||
|
|||
[Mikael Brassman](http://spoike.ghost.io/) wrote [Reflux](https://github.com/spoike/refluxjs), a library that implements Flux concepts. Note that it diverges significantly from the way we use Flux at Facebook. He explains [the reasons why in a blog post](http://spoike.ghost.io/deconstructing-reactjss-flux/). |
|||
|
|||
<center> |
|||
<a href="http://spoike.ghost.io/deconstructing-reactjss-flux/"><img src="/react/img/blog/reflux-flux.png" width="400" /></a> |
|||
</center> |
|||
|
|||
|
|||
## React and Flux Interview |
|||
|
|||
[Ian Obermiller](http://ianobermiller.com/), engineer at Facebook, [made a lengthy interview](http://ianobermiller.com/blog/2014/09/15/react-and-flux-interview/) on the experience of using React and Flux in order to build probably the biggest React application ever written so far. |
|||
|
|||
> I’ve actually said this many times to my team too, I love React. It’s really great for making these complex applications. One thing that really surprised me with it is that React combined with a sane module system like CommonJS, and making sure that you actually modulize your stuff properly has scaled really well to a team of almost 10 developers working on hundreds of files and tens of thousands of lines of code. |
|||
> |
|||
> Really, a fairly large code base... stuff just works. You don’t have to worry about mutating, and the state of the DOM just really makes stuff easy. Just conceptually it’s easier just to think about here’s what I have, here’s my data, here’s how it renders, I don’t care about anything else. For most cases that is really simplifying and makes it really fast to do stuff. |
|||
> |
|||
> [Read the full interview...](http://ianobermiller.com/blog/2014/09/15/react-and-flux-interview/) |
|||
|
|||
|
|||
## Adobe's Brackets Project Tree |
|||
|
|||
[Kevin Dangoor](http://www.kevindangoor.com/) is converting the project tree of [Adobe's Bracket text editor](http://brackets.io/) to React and Flux. He wrote about his experience [using Flux](http://www.kevindangoor.com/2014/09/intro-to-the-new-brackets-project-tree/). |
|||
|
|||
<center> |
|||
<a href="http://www.kevindangoor.com/2014/09/intro-to-the-new-brackets-project-tree/"><img src="/react/img/blog/flux-diagram.png" width="400" /></a> |
|||
</center> |
|||
|
|||
|
|||
## Async Requests with Flux Revisited |
|||
|
|||
[Reto Schläpfer](http://www.code-experience.com/the-code-experience/) came back to a Flux project he hasn't worked on for a month and [saw many ways to improve the way he implemented Flux](http://www.code-experience.com/async-requests-with-react-js-and-flux-revisited/). He summarized his learnings in a blog post. |
|||
|
|||
> The smarter way is to call the Web Api directly from an Action Creator and then make the Api dispatch an event with the request result as a payload. The Store(s) can choose to listen on those request actions and change their state accordingly. |
|||
> |
|||
> Before I show some updated code snippets, let me explain why this is superior: |
|||
> |
|||
> - There should be only one channel for all state changes: The Dispatcher. This makes debugging easy because it just requires a single console.log in the dispatcher to observe every single state change trigger. |
|||
> |
|||
> - Asynchronously executed callbacks should not leak into Stores. The consequences of it are just to hard to fully foresee. This leads to elusive bugs. Stores should only execute synchronous code. Otherwise they are too hard to understand. |
|||
> |
|||
> - Avoiding actions firing other actions makes your app simple. We use the newest Dispatcher implementation from Facebook that does not allow a new dispatch while dispatching. It forces you to do things right. |
|||
> |
|||
> [Read the full article...](http://www.code-experience.com/async-requests-with-react-js-and-flux-revisited/) |
|||
|
|||
|
|||
## Undo-Redo with Immutable Data Structures |
|||
|
|||
[Ameya Karve](https://github.com/ameyakarve) explained how to use [Mori](https://github.com/swannodette/mori), a library that provides immutable data structures, in order to [implement undo-redo](http://ameyakarve.com/jekyll/update/2014/02/06/Undo-React-Flux-Mori.html). This usually very challenging feature only takes a few lines of code with Flux! |
|||
|
|||
```javascript |
|||
undo: function() { |
|||
this.redoStates = Mori.conj(this.redoStates, Mori.first(this.undoStates)); |
|||
this.undoStates = Mori.drop(1, this.undoStates); |
|||
this.todosState = Mori.first(this.undoStates); |
|||
this.canUndo = Mori.count(this.undoStates) > 1; |
|||
this.canRedo = true; |
|||
if (Mori.count(this.undoStates) > 1) { |
|||
this.todos = JSON.parse(this.todosState); |
|||
} else { |
|||
this.todos = []; |
|||
} |
|||
this.emit('change'); |
|||
}, |
|||
``` |
|||
|
|||
|
|||
## Flux in practice |
|||
|
|||
[Gary Chambers](https://twitter.com/garychambers108) wrote a [guide to get started with Flux](https://medium.com/@garychambers108/flux-in-practice-ec08daa9041a). This is a very practical introduction to Flux. |
|||
|
|||
> So, what does it actually mean to write an application in the Flux way? At that moment of inspiration, when faced with an empty text editor, how should you begin? This post follows the process of building a Flux-compliant application from scratch. |
|||
> |
|||
> [Read the full guide...](https://medium.com/@garychambers108/flux-in-practice-ec08daa9041a) |
|||
|
|||
|
|||
## Components, React and Flux |
|||
|
|||
[Dan Abramov](https://twitter.com/dan_abramov) working at Stampsy made a talk about React and Flux. It's a very good overview of the concepts at play. |
|||
|
|||
<iframe src="//slides.com/danabramov/components-react-flux-wip/embed" width="650" height="315" scrolling="no" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe> |
|||
|
|||
|
|||
## React and Flux |
|||
|
|||
[Christian Alfoni](https://github.com/christianalfoni) wrote an article where [he compares Backbone, Angular and Flux](http://christianalfoni.github.io/javascript/2014/08/20/react-js-and-flux.html) on a simple example that's representative of a real project he worked on. |
|||
|
|||
> Wow, that was a bit more code! Well, try to think of it like this. In the above examples, if we were to do any changes to the application we would probably have to move things around. In the FLUX example we have considered that from the start. |
|||
> |
|||
> Any changes to the application is adding, not moving things around. If you need a new store, just add it and make components dependant of it. If you need more views, create a component and use it inside any other component without affecting their current "parent controller or models". |
|||
> |
|||
> [Read the full article...](http://christianalfoni.github.io/javascript/2014/08/20/react-js-and-flux.html) |
|||
|
|||
|
|||
|
|||
## Flux: Step by Step approach |
|||
|
|||
[Nicola Paolucci](https://github.com/durdn) from Atlassian wrote a great guide to help your getting understand [Flux step by step](http://blogs.atlassian.com/2014/08/flux-architecture-step-by-step/). |
|||
|
|||
<center> |
|||
<a href="http://blogs.atlassian.com/2014/08/flux-architecture-step-by-step/"><img src="/react/img/blog/flux-chart.png" width="400" /></a> |
|||
</center> |
|||
|
|||
|
|||
## DeLorean: Back to the future! |
|||
|
|||
[DeLorean](https://github.com/deloreanjs/delorean) is a tiny Flux pattern implementation developed by [Fatih Kadir Akin](https://github.com/f). |
|||
|
|||
> |
|||
- Unidirectional data flow, it makes your app logic simpler than MVC |
|||
- Automatically listens to data changes and keeps your data updated |
|||
- Makes data more consistent across your whole application |
|||
- It's framework agnostic, completely. There's no view framework dependency |
|||
- Very small, just 4K gzipped |
|||
- Built-in React.js integration, easy to use with Flight.js and Ractive.js and probably all others |
|||
- Improve your UI/data consistency using rollbacks |
|||
|
|||
|
|||
## Facebook's iOS Infrastructure |
|||
|
|||
Last but not least, Flux and React ideas are not limited to JavaScript inside of the browser. The iOS team at Facebook re-implemented Newsfeed using very similar patterns. |
|||
|
|||
<iframe width="650" height="315" src="//www.youtube.com/embed/XhXC4SKOGfQ" frameborder="0" allowfullscreen></iframe> |
|||
|
|||
|
|||
## Random Tweet |
|||
|
|||
<blockquote class="twitter-tweet" lang="en"><p>If you build your app with flux, you can swap out React for a canvas or svg view layer and keep 85% of your code. (or the thing after React)</p>— Ryan Florence (@ryanflorence) <a href="https://twitter.com/ryanflorence/status/507309645372076034">September 3, 2014</a></blockquote> |
|||
@ -0,0 +1,15 @@ |
|||
--- |
|||
title: React.js Conf |
|||
author: Vjeux |
|||
--- |
|||
|
|||
Every few weeks someone asks us when we are going to organize a conference for React. Our answer has always been "some day". In the mean time, people have been talking about React at other JavaScript conferences around the world. But now the time has finally come for us to have a conference of our own. |
|||
|
|||
**We're happy to announce [React.js Conf](http://conf.reactjs.com/)! It will take place January 28-29, 2015 on Facebook's campus in Menlo Park, California.** |
|||
|
|||
Before we open registration, [we're looking for great talks](http://conf.reactjs.com/call-for-presenters.html). We want to see how you pushed application development forward! If you ever talked to a meet-up, pitched React to your co-workers, or done something awesome and want to talk about it, let us know! |
|||
|
|||
Here are some areas of research we want to explore during the conference if you need some inspiration: server-side rendering, data fetching, language features (eg es6, clojure), immutability, rendering targets (eg svg, canvas), real-time updates... |
|||
|
|||
We look forward to seeing many of you in person in just a few short months! |
|||
|
|||
@ -0,0 +1,127 @@ |
|||
--- |
|||
title: React v0.12 |
|||
author: Paul O’Shannessy |
|||
--- |
|||
|
|||
We're happy to announce the availability of React v0.12! After over a week of baking as the release candidate, we uncovered and fixed a few small issues. Thanks to all of you who upgraded and gave us feedback! |
|||
|
|||
We have talked a lot about some of the bigger changes in this release. [We introduced new terminology](/react/blog/2014/10/14/introducing-react-elements.html) and changed APIs to clean up and simplify some of the concepts of React. [We also made several changes to JSX](/react/blog/2014/10/16/react-v0.12-rc1.html) and deprecated a few functions. We won't go into depth about these changes again but we encourage you to read up on these changes in the linked posts. We'll summarize these changes and discuss some of the other changes and how they may impact you below. As always, a full changelog is also included below. |
|||
|
|||
|
|||
The release is available for download: |
|||
|
|||
* **React** |
|||
Dev build with warnings: <http://fb.me/react-0.12.0.js> |
|||
Minified build for production: <http://fb.me/react-0.12.0.min.js> |
|||
* **React with Add-Ons** |
|||
Dev build with warnings: <http://fb.me/react-with-addons-0.12.0.js> |
|||
Minified build for production: <http://fb.me/react-with-addons-0.12.0.min.js> |
|||
* **In-Browser JSX transformer** |
|||
<http://fb.me/JSXTransformer-0.12.0.js> |
|||
|
|||
We've also published version `0.12.0` of the `react` and `react-tools` packages on npm and the `react` package on bower. |
|||
|
|||
## New Terminology & Updated APIs |
|||
|
|||
v0.12 is bringing about some new terminology. [We introduced](/react/blog/2014/10/14/introducing-react-elements.html) this 2 weeks ago and we've also documented it in [a new section of the documentation](/react/docs/glossary.html). As a part of this, we also corrected many of our top-level APIs to align with the terminology. `Component` has been removed from all of our `React.render*` methods. While at one point the argument you passed to these functions was called a Component, it no longer is. You are passing ReactElements. To align with `render` methods in your component classes, we decided to keep the top-level functions short and sweet. `React.renderComponent` is now `React.render`. |
|||
|
|||
We also corrected some other misnomers. `React.isValidComponent` actually determines if the argument is a ReactElement, so it has been renamed to `React.isValidElement`. In the same vein, `React.PropTypes.component` is now `React.PropTypes.element` and `React.PropTypes.renderable` is now `React.PropTypes.node`. |
|||
|
|||
The old methods will still work but will warn upon first use. They will be removed in v0.13. |
|||
|
|||
## JSX Changes |
|||
|
|||
[We talked more in depth about these before](/react/blog/2014/10/16/react-v0.12-rc1.html#jsx-changes), so here are the highlights. |
|||
|
|||
* No more `/** @jsx React.DOM */`! |
|||
* We no longer transform to a straight function call. `<Component/>` now becomes `React.createElement(Component)` |
|||
* DOM components don't make use of `React.DOM`, instead we pass the tag name directly. `<div/>` becomes `React.createElement('div')` |
|||
* We introduced spread attributes as a quick way to transfer props. |
|||
|
|||
## DevTools Improvements, No More `__internals` |
|||
|
|||
For months we've gotten complaints about the React DevTools message. It shouldn't have logged the up-sell message when you were already using the DevTools. Unfortunately this was because the way we implemented these tools resulted in the DevTools knowing about React, but not the reverse. We finally gave this some attention and enabled React to know if the DevTools are installed. We released an update to the devtools several weeks ago making this possible. Extensions in Chrome should auto-update so you probably already have the update installed! |
|||
|
|||
As a result of this update, we no longer need to expose several internal modules to the world. If you were taking advantage of this implementation detail, your code will break. `React.__internals` is no more. |
|||
|
|||
## License Change - BSD |
|||
|
|||
We updated the license on React to the BSD 3-Clause license with an explicit patent grant. Previously we used the Apache 2 license. These licenses are very similar and our extra patent grant is equivalent to the grant provided in the Apache license. You can still use React with the confidence that we have granted the use of any patents covering it. This brings us in line with the same licensing we use across the majority of our open source projects at Facebook. |
|||
|
|||
You can read the full text of the [LICENSE](https://github.com/facebook/react/blob/master/LICENSE) and [`PATENTS`](https://github.com/facebook/react/blob/master/PATENTS) files on GitHub. |
|||
|
|||
- - - |
|||
|
|||
## Changelog |
|||
|
|||
### React Core |
|||
|
|||
#### Breaking Changes |
|||
|
|||
* `key` and `ref` moved off props object, now accessible on the element directly |
|||
* React is now BSD licensed with accompanying Patents grant |
|||
* Default prop resolution has moved to Element creation time instead of mount time, making them effectively static |
|||
* `React.__internals` is removed - it was exposed for DevTools which no longer needs access |
|||
* Composite Component functions can no longer be called directly - they must be wrapped with `React.createFactory` first. This is handled for you when using JSX. |
|||
|
|||
#### New Features |
|||
|
|||
* Spread operator (`{...}`) introduced to deprecate `this.transferPropsTo` |
|||
* Added support for more HTML attributes: `acceptCharset`, `classID`, `manifest` |
|||
|
|||
#### Deprecations |
|||
|
|||
* `React.renderComponent` --> `React.render` |
|||
* `React.renderComponentToString` --> `React.renderToString` |
|||
* `React.renderComponentToStaticMarkup` --> `React.renderToStaticMarkup` |
|||
* `React.isValidComponent` --> `React.isValidElement` |
|||
* `React.PropTypes.component` --> `React.PropTypes.element` |
|||
* `React.PropTypes.renderable` --> `React.PropTypes.node` |
|||
* **DEPRECATED** `React.isValidClass` |
|||
* **DEPRECATED** `instance.transferPropsTo` |
|||
* **DEPRECATED** Returning `false` from event handlers to preventDefault |
|||
* **DEPRECATED** Convenience Constructor usage as function, instead wrap with `React.createFactory` |
|||
* **DEPRECATED** use of `key={null}` to assign implicit keys |
|||
|
|||
#### Bug Fixes |
|||
|
|||
* Better handling of events and updates in nested results, fixing value restoration in "layered" controlled components |
|||
* Correctly treat `event.getModifierState` as case sensitive |
|||
* Improved normalization of `event.charCode` |
|||
* Better error stacks when involving autobound methods |
|||
* Removed DevTools message when the DevTools are installed |
|||
* Correctly detect required language features across browsers |
|||
* Fixed support for some HTML attributes: |
|||
* `list` updates correctly now |
|||
* `scrollLeft`, `scrollTop` removed, these should not be specified as props |
|||
* Improved error messages |
|||
|
|||
### React With Addons |
|||
|
|||
#### New Features |
|||
|
|||
* `React.addons.batchedUpdates` added to API for hooking into update cycle |
|||
|
|||
#### Breaking Changes |
|||
|
|||
* `React.addons.update` uses `assign` instead of `copyProperties` which does `hasOwnProperty` checks. Properties on prototypes will no longer be updated correctly. |
|||
|
|||
#### Bug Fixes |
|||
|
|||
* Fixed some issues with CSS Transitions |
|||
|
|||
### JSX |
|||
|
|||
#### Breaking Changes |
|||
|
|||
* Enforced convention: lower case tag names are always treated as HTML tags, upper case tag names are always treated as composite components |
|||
* JSX no longer transforms to simple function calls |
|||
|
|||
#### New Features |
|||
|
|||
* `@jsx React.DOM` no longer required |
|||
* spread (`{...}`) operator introduced to allow easier use of props |
|||
|
|||
#### Bug Fixes |
|||
|
|||
* JSXTransformer: Make sourcemaps an option when using APIs directly (eg, for react-rails) |
|||
@ -0,0 +1,71 @@ |
|||
--- |
|||
id: jsx-spread |
|||
title: JSX Spread Attributes |
|||
permalink: jsx-spread.html |
|||
prev: jsx-in-depth.html |
|||
next: jsx-gotchas.html |
|||
--- |
|||
|
|||
If you know all the properties that you want to place on a component ahead of time, it is easy to use JSX: |
|||
|
|||
```javascript |
|||
var component = <Component foo={x} bar={y} />; |
|||
``` |
|||
|
|||
## Mutating Props is Bad, mkay |
|||
|
|||
If you don't know which properties you want to set, you might be tempted to add them onto the object later: |
|||
|
|||
```javascript |
|||
var component = <Component />; |
|||
component.props.foo = x; // bad |
|||
component.props.bar = y; // also bad |
|||
``` |
|||
|
|||
This is an anti-pattern because it means that we can't help you check the right propTypes until way later. This means that your propTypes errors end up with a cryptic stack trace. |
|||
|
|||
The props should be considered immutable at this point. Mutating the props object somewhere else could cause unexpected consequences so ideally it would be a frozen object at this point. |
|||
|
|||
## Spread Attributes |
|||
|
|||
Now you can use a new feature of JSX called spread attributes: |
|||
|
|||
```javascript |
|||
var props = {}; |
|||
props.foo = x; |
|||
props.bar = y; |
|||
var component = <Component {...props} />; |
|||
``` |
|||
|
|||
The properties of the object that you pass in are copied onto the component's props. |
|||
|
|||
You can use this multiple times or combine it with other attributes. The specification order is important. Later attributes override previous ones. |
|||
|
|||
```javascript |
|||
var props = { foo: 'default' }; |
|||
var component = <Component {...props} foo={'override'} />; |
|||
console.log(component.props.foo); // 'override' |
|||
``` |
|||
|
|||
## What's with the weird `...` notation? |
|||
|
|||
The `...` operator (or spread operator) is already supported for [arrays in ES6](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_operator). There is also an ES7 proposal for [Object Rest and Spread Properties](https://github.com/sebmarkbage/ecmascript-rest-spread). |
|||
|
|||
In fact, you can already use this in our code base as an experimental syntax: |
|||
|
|||
```javascript |
|||
var oldObj = { foo: 'hello', bar: 'world' }; |
|||
var newObj = { ...oldObj, foo: 'hi' }; |
|||
console.log(newObj.foo); // 'hi'; |
|||
console.log(newObj.bar); // 'world'; |
|||
``` |
|||
|
|||
Merging two objects can be expressed as: |
|||
|
|||
```javascript |
|||
var ab = { ...a, ...b }; |
|||
``` |
|||
|
|||
> Note: |
|||
> |
|||
> Use the [JSX command-line tool](http://npmjs.org/package/react-tools) with the `--harmony` flag to activate the experimental ES7 syntax. |
|||
@ -0,0 +1,159 @@ |
|||
--- |
|||
id: transferring-props |
|||
title: Transferring Props |
|||
permalink: transferring-props.html |
|||
prev: reusable-components.html |
|||
next: forms.html |
|||
--- |
|||
|
|||
It's a common pattern in React to wrap a component in an abstraction. The outer component exposes a simple property to do something that might have more complex implementation details. |
|||
|
|||
You can use [JSX spread attributes](/react/docs/jsx-spread.html) to merge the old props with additional values: |
|||
|
|||
```javascript |
|||
return <Component {...this.props} more="values" />; |
|||
``` |
|||
|
|||
If you don't use JSX, you can use any object helper such as ES6 `Object.assign` or Underscore `_.extend`: |
|||
|
|||
```javascript |
|||
return Component(Object.assign({}, this.props, { more: 'values' })); |
|||
``` |
|||
|
|||
The rest of this tutorial explains best practices. It uses JSX and experimental ES7 syntax. |
|||
|
|||
## Manual Transfer |
|||
|
|||
Most of the time you should explicitly pass the properties down. That ensures that you only exposes a subset of the inner API, one that you know will work. |
|||
|
|||
```javascript |
|||
var FancyCheckbox = React.createClass({ |
|||
render: function() { |
|||
var fancyClass = this.props.checked ? 'FancyChecked' : 'FancyUnchecked'; |
|||
return ( |
|||
<div className={fancyClass} onClick={this.props.onClick}> |
|||
{this.props.children} |
|||
</div> |
|||
); |
|||
} |
|||
}); |
|||
React.render( |
|||
<FancyCheckbox checked={true} onClick={console.log}> |
|||
Hello world! |
|||
</FancyCheckbox>, |
|||
document.body |
|||
); |
|||
``` |
|||
|
|||
But what about the `name` prop? Or the `title` prop? Or `onMouseOver`? |
|||
|
|||
## Transferring with `...` in JSX |
|||
|
|||
Sometimes it's fragile and tedious to pass every property along. In that case you can use [destructuring assignment](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment) with rest properties to extract a set of unknown properties. |
|||
|
|||
List out all the properties that you would like to consume, followed by `...other`. |
|||
|
|||
```javascript |
|||
var { checked, ...other } = this.props; |
|||
``` |
|||
|
|||
This ensures that you pass down all the props EXCEPT the ones you're consuming yourself. |
|||
|
|||
```javascript |
|||
var FancyCheckbox = React.createClass({ |
|||
render: function() { |
|||
var { checked, ...other } = this.props; |
|||
var fancyClass = checked ? 'FancyChecked' : 'FancyUnchecked'; |
|||
// `other` contains { onClick: console.log } but not the checked property |
|||
return ( |
|||
<div {...other} className={fancyClass} /> |
|||
); |
|||
} |
|||
}); |
|||
React.render( |
|||
<FancyCheckbox checked={true} onClick={console.log}> |
|||
Hello world! |
|||
</FancyCheckbox>, |
|||
document.body |
|||
); |
|||
``` |
|||
|
|||
> NOTE: |
|||
> |
|||
> In the example above, the `checked` prop is also a valid DOM attribute. If you didn't use destructuring in this way you might inadvertently pass it along. |
|||
|
|||
Always use the destructuring pattern when transferring unknown `other` props. |
|||
|
|||
```javascript |
|||
var FancyCheckbox = React.createClass({ |
|||
render: function() { |
|||
var fancyClass = this.props.checked ? 'FancyChecked' : 'FancyUnchecked'; |
|||
// ANTI-PATTERN: `checked` would be passed down to the inner component |
|||
return ( |
|||
<div {...this.props} className={fancyClass} /> |
|||
); |
|||
} |
|||
}); |
|||
``` |
|||
|
|||
## Consuming and Transferring the Same Prop |
|||
|
|||
If your component wants to consume a property but also pass it along, you can repass it explicitly `checked={checked}`. This is preferable to passing the full `this.props` object since it's easier to refactor and lint. |
|||
|
|||
```javascript |
|||
var FancyCheckbox = React.createClass({ |
|||
render: function() { |
|||
var { checked, title, ...other } = this.props; |
|||
var fancyClass = checked ? 'FancyChecked' : 'FancyUnchecked'; |
|||
var fancyTitle = checked ? 'X ' + title : 'O ' + title; |
|||
return ( |
|||
<label> |
|||
<input {...other} |
|||
checked={checked} |
|||
className={fancyClass} |
|||
type="checkbox" |
|||
/> |
|||
{fancyTitle} |
|||
</label> |
|||
); |
|||
} |
|||
}); |
|||
``` |
|||
|
|||
> NOTE: |
|||
> |
|||
> Order matters. By putting the `{...other}` before your JSX props you ensure that the consumer of your component can't override them. In the example above we have guaranteed that the input will be of type `"checkbox"`. |
|||
|
|||
## Rest and Spread Properties `...` |
|||
|
|||
Rest properties allow you to extract the remaining properties from an object into a new object. It excludes every other property listed in the destructuring pattern. |
|||
|
|||
This is an experimental implementation of an [ES7 proposal](https://github.com/sebmarkbage/ecmascript-rest-spread). |
|||
|
|||
```javascript |
|||
var { x, y, ...z } = { x: 1, y: 2, a: 3, b: 4 }; |
|||
x; // 1 |
|||
y; // 2 |
|||
z; // { a: 3, b: 4 } |
|||
``` |
|||
|
|||
> Note: |
|||
> |
|||
> Use the [JSX command-line tool](http://npmjs.org/package/react-tools) with the `--harmony` flag to activate the experimental ES7 syntax. |
|||
|
|||
## Transferring with Underscore |
|||
|
|||
If you don't use JSX, you can use a library to achieve the same pattern. Underscore supports `_.omit` to filter out properties and `_.extend` to copy properties onto a new object. |
|||
|
|||
```javascript |
|||
var FancyCheckbox = React.createClass({ |
|||
render: function() { |
|||
var checked = this.props.checked; |
|||
var other = _.omit(this.props, 'checked'); |
|||
var fancyClass = checked ? 'FancyChecked' : 'FancyUnchecked'; |
|||
return ( |
|||
React.DOM.div(_.extend({}, other, { className: fancyClass })) |
|||
); |
|||
} |
|||
}); |
|||
``` |
|||
@ -0,0 +1,192 @@ |
|||
--- |
|||
id: glossary |
|||
title: React (Virtual) DOM Terminology |
|||
permalink: glossary.html |
|||
prev: reconciliation.html |
|||
--- |
|||
|
|||
In React's terminology, there are five core types that are important to distinguish: |
|||
|
|||
- [ReactElement / ReactElement Factory](#react-elements) |
|||
- [ReactNode](#react-nodes) |
|||
- [ReactComponent / ReactComponent Class](#react-components) |
|||
|
|||
## React Elements |
|||
|
|||
The primary type in React is the `ReactElement`. It has four properties: `type`, `props`, `key` and `ref`. It has no methods and nothing on the prototype. |
|||
|
|||
You can create one of these object through `React.createElement`. |
|||
|
|||
```javascript |
|||
var root = React.createElement('div'); |
|||
``` |
|||
|
|||
To render a new tree into the DOM, you create `ReactElement`s and pass them to `React.render` a long with a regular DOM `Element` (`HTMLElement` or `SVGElement`). `ReactElement`s are not to be confused with DOM `Element`s. A `ReactElement` is a light, stateless, immutable, virtual representation of a DOM `Element`. It is a virtual DOM. |
|||
|
|||
```javascript |
|||
React.render(root, document.body); |
|||
``` |
|||
|
|||
To add properties to a DOM element, pass a properties object as the second argument and children to the third argument. |
|||
|
|||
```javascript |
|||
var child = React.createElement('li', null, 'Text Content'); |
|||
var root = React.createElement('ul', { className: 'my-list' }, child); |
|||
React.render(root, document.body); |
|||
``` |
|||
|
|||
If you use React JSX, then these `ReactElement`s are created for you. So this is equivalent: |
|||
|
|||
```javascript |
|||
var root = <ul className="my-list"> |
|||
<li>Text Content</li> |
|||
</ul>; |
|||
React.render(root, document.body); |
|||
``` |
|||
|
|||
__Factories__ |
|||
|
|||
A `ReactElement`-factory is simply a function that generates a `ReactElement` with a particular `type` property. React has a built-in helper for you to create factories. It's effectively just: |
|||
|
|||
```javascript |
|||
function createFactory(type){ |
|||
return React.createElement.bind(null, type); |
|||
} |
|||
``` |
|||
|
|||
It allows you to create a convenient short-hand instead of typing out `React.createElement('div')` all the time. |
|||
|
|||
```javascript |
|||
var div = React.createFactory('div'); |
|||
var root = div({ className: 'my-div' }); |
|||
React.render(root, document.body); |
|||
``` |
|||
|
|||
React already have built-in factories for common HTML tags: |
|||
|
|||
```javascript |
|||
var root = React.DOM.ul({ className: 'my-list' }, |
|||
React.DOM.li(null, 'Text Content') |
|||
); |
|||
``` |
|||
|
|||
If you are using JSX you have no need for factories. JSX already provides a convenient short-hand for creating `ReactElement`s. |
|||
|
|||
|
|||
## React Nodes |
|||
|
|||
A `ReactNode` can be either: |
|||
- `ReactElement` |
|||
- `string` (aka `ReactText`) |
|||
- `number` (aka `ReactText`) |
|||
- Array of `ReactNode`s (aka `ReactFragment`) |
|||
|
|||
These are used as properties of other `ReactElement`s to represent children. Effectively they create a tree of `ReactElement`s. |
|||
|
|||
|
|||
## React Components |
|||
|
|||
You can use React using only `ReactElement`s but to really take advantage of React, you'll want to use `ReactComponent`s to create encapsulations with embedded state. |
|||
|
|||
A `ReactComponent` Class is simply just a JavaScript class (or "constructor function"). |
|||
|
|||
```javascript |
|||
var MyComponent = React.createClass({ |
|||
render: function() { |
|||
... |
|||
} |
|||
}); |
|||
``` |
|||
|
|||
When this constructor is invoked it is expected to return an object with at least a `render` method on it. This object is referred to as a `ReactComponent`. |
|||
|
|||
```javascript |
|||
var component = new MyComponent(props); // never do this |
|||
``` |
|||
|
|||
Other than for testing, you would normally __never__ call this constructor yourself. React calls it for you. |
|||
|
|||
Instead, you pass the `ReactComponent` Class to `createElement` you get a `ReactElement`. |
|||
|
|||
```javascript |
|||
var element = React.createElement(MyComponent); |
|||
``` |
|||
|
|||
OR using JSX: |
|||
|
|||
```javascript |
|||
var element = <MyComponent />; |
|||
``` |
|||
|
|||
When this is passed to `React.render`, React will call the constructor for you and create a `ReactComponent`, which returned. |
|||
|
|||
```javascript |
|||
var component = React.render(element, document.body); |
|||
``` |
|||
|
|||
If you keep calling `React.render` with the same type of `ReactElement` and the same container DOM `Element` it always returns the same instance. This instance is stateful. |
|||
|
|||
```javascript |
|||
var componentA = React.render(<MyComponent />, document.body); |
|||
var componentB = React.render(<MyComponent />, document.body); |
|||
componentA === componentB; // true |
|||
``` |
|||
|
|||
This is why you shouldn't construct your own instance. Instead, `ReactElement` is a virtual `ReactComponent` before it gets constructed. An old and new `ReactElement` can be compared to see if a new `ReactComponent` instance is created or if the existing one is reused. |
|||
|
|||
The `render` method of a `ReactComponent` is expected to return another `ReactElement`. This allows these components to be composed. Ultimately the render resolves into `ReactElement` with a `string` tag which instantiates a DOM `Element` instance and inserts it into the document. |
|||
|
|||
|
|||
## Formal Type Definitions |
|||
|
|||
__Entry Point__ |
|||
|
|||
``` |
|||
React.render = (ReactElement, HTMLElement | SVGElement) => ReactComponent; |
|||
``` |
|||
|
|||
__Nodes and Elements__ |
|||
|
|||
``` |
|||
type ReactNode = ReactElement | ReactFragment | ReactText; |
|||
|
|||
type ReactElement = ReactComponentElement | ReactDOMElement; |
|||
|
|||
type ReactDOMElement = { |
|||
type : string, |
|||
props : { |
|||
children : ReactNodeList, |
|||
className : string, |
|||
etc. |
|||
}, |
|||
key : string | boolean | number | null, |
|||
ref : string | null |
|||
}; |
|||
|
|||
type ReactComponentElement<TProps> = { |
|||
type : ReactClass<TProps>, |
|||
props : TProps, |
|||
key : string | boolean | number | null, |
|||
ref : string | null |
|||
}; |
|||
|
|||
type ReactFragment = Array<ReactNode | ReactEmpty>; |
|||
|
|||
type ReactNodeList = ReactNode | ReactEmpty; |
|||
|
|||
type ReactText = string | number; |
|||
|
|||
type ReactEmpty = null | undefined | boolean; |
|||
``` |
|||
|
|||
__Classes and Components__ |
|||
|
|||
``` |
|||
type ReactClass<TProps> = (TProps) => ReactComponent<TProps>; |
|||
|
|||
type ReactComponent<TProps> = { |
|||
props : TProps, |
|||
render : () => ReactElement |
|||
}; |
|||
``` |
|||
|
|||
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Reference in new issue