qt: move window.get{Open,Save}FileName to util

Sometimes we want its "remember path" behaviour but it does not make sense to
parent the dialog from main window. When so, caller code no longer needs to
get a reference to a main window.

Also rm last usages of get_parent_main_window().

electrum/gui/qt/address_dialog.py

@@ -87,14 +87,14 @@ class AddressDialog(WindowModalDialog):
         redeem_script = self.wallet.get_redeem_script(address)
         if redeem_script:
             vbox.addWidget(QLabel(_("Redeem Script") + ':'))
-            redeem_e = ShowQRTextEdit(text=redeem_script)
+            redeem_e = ShowQRTextEdit(text=redeem_script, config=self.config)
             redeem_e.addCopyButton(self.app)
             vbox.addWidget(redeem_e)
 
         witness_script = self.wallet.get_witness_script(address)
         if witness_script:
             vbox.addWidget(QLabel(_("Witness Script") + ':'))
-            witness_e = ShowQRTextEdit(text=witness_script)
+            witness_e = ShowQRTextEdit(text=witness_script, config=self.config)
             witness_e.addCopyButton(self.app)
             vbox.addWidget(witness_e)
 

electrum/gui/qt/completion_text_edit.py

@@ -32,8 +32,8 @@ from .util import ButtonsTextEdit
 
 class CompletionTextEdit(ButtonsTextEdit):
 
-    def __init__(self, parent=None):
-        super(CompletionTextEdit, self).__init__(parent)
+    def __init__(self):
+        ButtonsTextEdit.__init__(self)
         self.completer = None
         self.moveCursor(QTextCursor.End)
         self.disable_suggestions()

electrum/gui/qt/main_window.py

@@ -89,7 +89,8 @@ from .util import (read_QIcon, ColorScheme, text_dialog, icon_path, WaitingDialo
                    CloseButton, HelpButton, MessageBoxMixin, EnterButton,
                    import_meta_gui, export_meta_gui,
                    filename_field, address_field, char_width_in_lineedit, webopen,
-                   TRANSACTION_FILE_EXTENSION_FILTER_ANY, MONOSPACE_FONT)
+                   TRANSACTION_FILE_EXTENSION_FILTER_ANY, MONOSPACE_FONT,
+                   getOpenFileName, getSaveFileName)
 from .util import ButtonsTextEdit, ButtonsLineEdit
 from .installwizard import WIF_HELP_TEXT
 from .history_list import HistoryList, HistoryModel
@@ -841,38 +842,6 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
             except TypeError:
                 self.tray.showMessage("Electrum", message, QSystemTrayIcon.Information, 20000)
 
-
-
-    # custom wrappers for getOpenFileName and getSaveFileName, that remember the path selected by the user
-    def getOpenFileName(self, title, filter = ""):
-        directory = self.config.get('io_dir', os.path.expanduser('~'))
-        fileName, __ = QFileDialog.getOpenFileName(self, title, directory, filter)
-        if fileName and directory != os.path.dirname(fileName):
-            self.config.set_key('io_dir', os.path.dirname(fileName), True)
-        return fileName
-
-    def getSaveFileName(self, title, filename, filter="",
-                        *, default_extension: str = None,
-                        default_filter: str = None) -> Optional[str]:
-        directory = self.config.get('io_dir', os.path.expanduser('~'))
-        path = os.path.join(directory, filename)
-
-        file_dialog = QFileDialog(self, title, path, filter)
-        file_dialog.setAcceptMode(QFileDialog.AcceptSave)
-        if default_extension:
-            # note: on MacOS, the selected filter's first extension seems to have priority over this...
-            file_dialog.setDefaultSuffix(default_extension)
-        if default_filter:
-            assert default_filter in filter, f"default_filter={default_filter!r} does not appear in filter={filter!r}"
-            file_dialog.selectNameFilter(default_filter)
-        if file_dialog.exec() != QDialog.Accepted:
-            return None
-
-        selected_path = file_dialog.selectedFiles()[0]
-        if selected_path and directory != os.path.dirname(selected_path):
-            self.config.set_key('io_dir', os.path.dirname(selected_path), True)
-        return selected_path
-
     def timer_actions(self):
         self.request_list.refresh_status()
         # Note this runs in the GUI thread
@@ -2077,12 +2046,18 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
             def do_export():
                 key = pr.get_id()
                 name = str(key) + '.bip70'
-                fn = self.getSaveFileName(_("Save invoice to file"), name, filter="*.bip70")
+                fn = getSaveFileName(
+                    parent=self,
+                    title=_("Save invoice to file"),
+                    filename=name,
+                    filter="*.bip70",
+                    config=self.config,
+                )
                 if not fn:
                     return
                 with open(fn, 'wb') as f:
                     data = f.write(pr.raw)
-                self.show_message(_('BIP70 invoice saved as' + ' ' + fn))
+                self.show_message(_('BIP70 invoice saved as {}').format(fn))
             exportButton = EnterButton(_('Export'), do_export)
             buttons = Buttons(exportButton, CloseButton(d))
         else:
@@ -2113,7 +2088,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
             grid.addWidget(QLabel(_("Expires") + ':'), 4, 0)
             grid.addWidget(QLabel(format_time(invoice.time + invoice.exp)), 4, 1)
         vbox.addLayout(grid)
-        invoice_e = ShowQRTextEdit()
+        invoice_e = ShowQRTextEdit(config=self.config)
         invoice_e.addCopyButton(self.app)
         invoice_e.setText(invoice.invoice)
         vbox.addWidget(invoice_e)
@@ -2392,7 +2367,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
                 ks_vbox.setContentsMargins(0, 0, 0, 0)
                 ks_w.setLayout(ks_vbox)
 
-                mpk_text = ShowQRTextEdit(ks.get_master_public_key())
+                mpk_text = ShowQRTextEdit(ks.get_master_public_key(), config=self.config)
                 mpk_text.setMaximumHeight(150)
                 mpk_text.addCopyButton(self.app)
                 run_hook('show_xpub_button', mpk_text, ks)
@@ -2461,8 +2436,14 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
                     help_text=None, show_copy_text_btn=False):
         if not data:
             return
-        d = QRDialog(data, parent or self, title, help_text=help_text,
-                     show_copy_text_btn=show_copy_text_btn)
+        d = QRDialog(
+            data=data,
+            parent=parent or self,
+            title=title,
+            help_text=help_text,
+            show_copy_text_btn=show_copy_text_btn,
+            config=self.config,
+        )
         d.exec_()
 
     @protected
@@ -2482,14 +2463,9 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
         vbox.addWidget(QLabel(_("Address") + ': ' + address))
         vbox.addWidget(QLabel(_("Script type") + ': ' + xtype))
         vbox.addWidget(QLabel(_("Private key") + ':'))
-        keys_e = ShowQRTextEdit(text=pk)
+        keys_e = ShowQRTextEdit(text=pk, config=self.config)
         keys_e.addCopyButton(self.app)
         vbox.addWidget(keys_e)
-        # if redeem_script:
-        #     vbox.addWidget(QLabel(_("Redeem Script") + ':'))
-        #     rds_e = ShowQRTextEdit(text=redeem_script)
-        #     rds_e.addCopyButton(self.app)
-        #     vbox.addWidget(rds_e)
         vbox.addLayout(Buttons(CloseButton(d)))
         d.setLayout(vbox)
         d.exec_()
@@ -2701,8 +2677,12 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
         self.show_transaction(tx)
 
     def read_tx_from_file(self) -> Optional[Transaction]:
-        fileName = self.getOpenFileName(_("Select your transaction file"),
-                                        TRANSACTION_FILE_EXTENSION_FILTER_ANY)
+        fileName = getOpenFileName(
+            parent=self,
+            title=_("Select your transaction file"),
+            filter=TRANSACTION_FILE_EXTENSION_FILTER_ANY,
+            config=self.config,
+        )
         if not fileName:
             return
         try:

electrum/gui/qt/qrcodewidget.py

@@ -9,8 +9,9 @@ from PyQt5.QtWidgets import (
 )
 
 from electrum.i18n import _
+from electrum.simple_config import SimpleConfig
 
-from .util import WindowModalDialog, get_parent_main_window, WWLabel
+from .util import WindowModalDialog, WWLabel, getSaveFileName
 
 
 class QRCodeWidget(QWidget):
@@ -95,15 +96,17 @@ class QRDialog(WindowModalDialog):
 
     def __init__(
             self,
+            *,
             data,
             parent=None,
             title="",
             show_text=False,
-            *,
             help_text=None,
             show_copy_text_btn=False,
+            config: SimpleConfig,
     ):
         WindowModalDialog.__init__(self, parent, title)
+        self.config = config
 
         vbox = QVBoxLayout()
 
@@ -122,11 +125,12 @@ class QRDialog(WindowModalDialog):
         hbox.addStretch(1)
 
         def print_qr():
-            main_window = get_parent_main_window(self)
-            if main_window:
-                filename = main_window.getSaveFileName(_("Select where to save file"), "qrcode.png")
-            else:
-                filename, __ = QFileDialog.getSaveFileName(self, _("Select where to save file"), "qrcode.png")
+            filename = getSaveFileName(
+                parent=self,
+                title=_("Select where to save file"),
+                filename="qrcode.png",
+                config=self.config,
+            )
             if not filename:
                 return
             p = qrw.grab()

electrum/gui/qt/qrtextedit.py

@@ -4,14 +4,15 @@ from electrum.i18n import _
 from electrum.plugin import run_hook
 from electrum.simple_config import SimpleConfig
 
-from .util import ButtonsTextEdit, MessageBoxMixin, ColorScheme
+from .util import ButtonsTextEdit, MessageBoxMixin, ColorScheme, getOpenFileName
 
 
 class ShowQRTextEdit(ButtonsTextEdit):
 
-    def __init__(self, text=None):
+    def __init__(self, text=None, *, config: SimpleConfig):
         ButtonsTextEdit.__init__(self, text)
-        self.setReadOnly(1)
+        self.config = config
+        self.setReadOnly(True)
         icon = "qrcode_white.png" if ColorScheme.dark_scheme else "qrcode.png"
         self.addButton(icon, self.qr_show, _("Show as QR code"))
 
@@ -23,7 +24,11 @@ class ShowQRTextEdit(ButtonsTextEdit):
             s = str(self.toPlainText())
         except:
             s = self.toPlainText()
-        QRDialog(s, parent=self).exec_()
+        QRDialog(
+            data=s,
+            parent=self,
+            config=self.config,
+        ).exec_()
 
     def contextMenuEvent(self, e):
         m = self.createStandardContextMenu()
@@ -44,7 +49,11 @@ class ScanQRTextEdit(ButtonsTextEdit, MessageBoxMixin):
         run_hook('scan_text_edit', self)
 
     def file_input(self):
-        fileName, __ = QFileDialog.getOpenFileName(self, 'select file')
+        fileName = getOpenFileName(
+            parent=self,
+            title='select file',
+            config=self.config,
+        )
         if not fileName:
             return
         try:

electrum/gui/qt/seed_dialog.py

@@ -105,7 +105,7 @@ class SeedLayout(QVBoxLayout):
             if for_seed_words:
                 self.seed_e = ButtonsTextEdit()
             else:  # e.g. xpub
-                self.seed_e = ShowQRTextEdit()
+                self.seed_e = ShowQRTextEdit(config=self.config)
             self.seed_e.setReadOnly(True)
             self.seed_e.setText(seed)
         else:  # we expect user to enter text

electrum/gui/qt/transaction_dialog.py

@@ -53,7 +53,7 @@ from .util import (MessageBoxMixin, read_QIcon, Buttons, icon_path,
                    char_width_in_lineedit, TRANSACTION_FILE_EXTENSION_FILTER_SEPARATE,
                    TRANSACTION_FILE_EXTENSION_FILTER_ONLY_COMPLETE_TX,
                    TRANSACTION_FILE_EXTENSION_FILTER_ONLY_PARTIAL_TX,
-                   BlockingWaitingDialog)
+                   BlockingWaitingDialog, getSaveFileName)
 
 from .fee_slider import FeeSlider, FeeComboBox
 from .confirm_tx_dialog import TxEditor
@@ -331,11 +331,15 @@ class BaseTxDialog(QDialog, MessageBoxMixin):
             extension = 'psbt'
             default_filter = TRANSACTION_FILE_EXTENSION_FILTER_ONLY_PARTIAL_TX
         name = f'{name}.{extension}'
-        fileName = self.main_window.getSaveFileName(_("Select where to save your transaction"),
-                                                    name,
-                                                    TRANSACTION_FILE_EXTENSION_FILTER_SEPARATE,
-                                                    default_extension=extension,
-                                                    default_filter=default_filter)
+        fileName = getSaveFileName(
+            parent=self,
+            title=_("Select where to save your transaction"),
+            filename=name,
+            filter=TRANSACTION_FILE_EXTENSION_FILTER_SEPARATE,
+            default_extension=extension,
+            default_filter=default_filter,
+            config=self.config,
+        )
         if not fileName:
             return
         if tx.is_complete():  # network tx hex

electrum/gui/qt/util.py

@@ -458,8 +458,14 @@ def filename_field(parent, config, defaultname, select_msg):
 
     def func():
         text = filename_e.text()
-        _filter = "*.csv" if text.endswith(".csv") else "*.json" if text.endswith(".json") else None
-        p, __ = QFileDialog.getSaveFileName(None, select_msg, text, _filter)
+        _filter = "*.csv" if defaultname.endswith(".csv") else "*.json" if defaultname.endswith(".json") else None
+        p = getSaveFileName(
+            parent=None,
+            title=select_msg,
+            filename=text,
+            filter=_filter,
+            config=config,
+        )
         if p:
             filename_e.setText(p)
 
@@ -935,9 +941,14 @@ class AcceptFileDragDrop:
         raise NotImplementedError()
 
 
-def import_meta_gui(electrum_window, title, importer, on_success):
+def import_meta_gui(electrum_window: 'ElectrumWindow', title, importer, on_success):
     filter_ = "JSON (*.json);;All files (*)"
-    filename = electrum_window.getOpenFileName(_("Open {} file").format(title), filter_)
+    filename = getOpenFileName(
+        parent=electrum_window,
+        title=_("Open {} file").format(title),
+        filter=filter_,
+        config=electrum_window.config,
+    )
     if not filename:
         return
     try:
@@ -949,10 +960,15 @@ def import_meta_gui(electrum_window, title, importer, on_success):
         on_success()
 
 
-def export_meta_gui(electrum_window, title, exporter):
+def export_meta_gui(electrum_window: 'ElectrumWindow', title, exporter):
     filter_ = "JSON (*.json);;All files (*)"
-    filename = electrum_window.getSaveFileName(_("Select file to save your {}").format(title),
-                                               'electrum_{}.json'.format(title), filter_)
+    filename = getSaveFileName(
+        parent=electrum_window,
+        title=_("Select file to save your {}").format(title),
+        filename='electrum_{}.json'.format(title),
+        filter=filter_,
+        config=electrum_window.config,
+    )
     if not filename:
         return
     try:
@@ -964,24 +980,44 @@ def export_meta_gui(electrum_window, title, exporter):
                                      .format(title, str(filename)))
 
 
-def get_parent_main_window(
-        widget, *, allow_wizard: bool = False,
-) -> Union[None, 'ElectrumWindow', 'InstallWizard']:
-    """Returns a reference to the ElectrumWindow this widget belongs to."""
-    from .main_window import ElectrumWindow
-    from .transaction_dialog import TxDialog
-    from .installwizard import InstallWizard
-    for _ in range(100):
-        if widget is None:
-            return None
-        if isinstance(widget, ElectrumWindow):
-            return widget
-        if isinstance(widget, TxDialog):
-            return widget.main_window
-        if isinstance(widget, InstallWizard) and allow_wizard:
-            return widget
-        widget = widget.parentWidget()
-    return None
+def getOpenFileName(*, parent, title, filter="", config: 'SimpleConfig') -> Optional[str]:
+    """Custom wrapper for getOpenFileName that remembers the path selected by the user."""
+    directory = config.get('io_dir', os.path.expanduser('~'))
+    fileName, __ = QFileDialog.getOpenFileName(parent, title, directory, filter)
+    if fileName and directory != os.path.dirname(fileName):
+        config.set_key('io_dir', os.path.dirname(fileName), True)
+    return fileName
+
+
+def getSaveFileName(
+        *,
+        parent,
+        title,
+        filename,
+        filter="",
+        default_extension: str = None,
+        default_filter: str = None,
+        config: 'SimpleConfig',
+) -> Optional[str]:
+    """Custom wrapper for getSaveFileName that remembers the path selected by the user."""
+    directory = config.get('io_dir', os.path.expanduser('~'))
+    path = os.path.join(directory, filename)
+
+    file_dialog = QFileDialog(parent, title, path, filter)
+    file_dialog.setAcceptMode(QFileDialog.AcceptSave)
+    if default_extension:
+        # note: on MacOS, the selected filter's first extension seems to have priority over this...
+        file_dialog.setDefaultSuffix(default_extension)
+    if default_filter:
+        assert default_filter in filter, f"default_filter={default_filter!r} does not appear in filter={filter!r}"
+        file_dialog.selectNameFilter(default_filter)
+    if file_dialog.exec() != QDialog.Accepted:
+        return None
+
+    selected_path = file_dialog.selectedFiles()[0]
+    if selected_path and directory != os.path.dirname(selected_path):
+        config.set_key('io_dir', os.path.dirname(selected_path), True)
+    return selected_path
 
 
 def icon_path(icon_basename):

electrum/plugins/coldcard/qt.py

@@ -5,7 +5,8 @@ import copy
 from PyQt5.QtCore import Qt, pyqtSignal
 from PyQt5.QtWidgets import QPushButton, QLabel, QVBoxLayout, QWidget, QGridLayout
 
-from electrum.gui.qt.util import WindowModalDialog, CloseButton, Buttons
+from electrum.gui.qt.util import (WindowModalDialog, CloseButton, Buttons, getOpenFileName,
+                                  getSaveFileName)
 from electrum.gui.qt.transaction_dialog import TxDialog
 from electrum.gui.qt.main_window import ElectrumWindow
 
@@ -64,8 +65,13 @@ class Plugin(ColdcardPlugin, QtPluginBase):
 
         basename = wallet.basename().rsplit('.', 1)[0]        # trim .json
         name = f'{basename}-cc-export.txt'.replace(' ', '-')
-        fileName = main_window.getSaveFileName(_("Select where to save the setup file"),
-                                                        name, "*.txt")
+        fileName = getSaveFileName(
+            parent=main_window,
+            title=_("Select where to save the setup file"),
+            filename=name,
+            filter="*.txt",
+            config=self.config,
+        )
         if fileName:
             with open(fileName, "wt") as f:
                 ColdcardPlugin.export_ms_wallet(wallet, f, basename)
@@ -191,10 +197,14 @@ class CKCCSettingsDialog(WindowModalDialog):
 
     def start_upgrade(self, client):
         # ask for a filename (must have already downloaded it)
-        mw = self.window
         dev = client.dev
 
-        fileName = mw.getOpenFileName("Select upgraded firmware file", "*.dfu")
+        fileName = getOpenFileName(
+            parent=self,
+            title="Select upgraded firmware file",
+            filter="*.dfu",
+            config=self.window.config,
+        )
         if not fileName:
             return
 
@@ -220,7 +230,7 @@ class CKCCSettingsDialog(WindowModalDialog):
             if magic != FW_HEADER_MAGIC:
                 raise ValueError("Bad magic")
         except Exception as exc:
-            mw.show_error("Does not appear to be a Coldcard firmware file.\n\n%s" % exc)
+            self.window.show_error("Does not appear to be a Coldcard firmware file.\n\n%s" % exc)
             return
 
         # TODO: 
@@ -228,7 +238,7 @@ class CKCCSettingsDialog(WindowModalDialog):
         # - warn them about the reboot?
         # - length checks
         # - add progress local bar
-        mw.show_message("Ready to Upgrade.\n\nBe patient. Unit will reboot itself when complete.")
+        self.window.show_message("Ready to Upgrade.\n\nBe patient. Unit will reboot itself when complete.")
 
         def doit():
             dlen, _ = dev.upload_file(firmware, verify=True)

electrum/plugins/safe_t/qt.py

@@ -9,7 +9,7 @@ from PyQt5.QtWidgets import (QVBoxLayout, QLabel, QGridLayout, QPushButton,
                              QMessageBox, QFileDialog, QSlider, QTabWidget)
 
 from electrum.gui.qt.util import (WindowModalDialog, WWLabel, Buttons, CancelButton,
-                                  OkButton, CloseButton)
+                                  OkButton, CloseButton, getOpenFileName)
 from electrum.i18n import _
 from electrum.plugin import hook
 from electrum.util import bh2u
@@ -276,8 +276,11 @@ class SettingsDialog(WindowModalDialog):
             invoke_client('toggle_passphrase', unpair_after=currently_enabled)
 
         def change_homescreen():
-            dialog = QFileDialog(self, _("Choose Homescreen"))
-            filename, __ = dialog.getOpenFileName()
+            filename = getOpenFileName(
+                parent=self,
+                title=_("Choose Homescreen"),
+                config=config,
+            )
             if not filename:
                 return  # user cancelled
 

electrum/plugins/trezor/qt.py

@@ -8,7 +8,7 @@ from PyQt5.QtWidgets import (QVBoxLayout, QLabel, QGridLayout, QPushButton,
                              QMessageBox, QFileDialog, QSlider, QTabWidget)
 
 from electrum.gui.qt.util import (WindowModalDialog, WWLabel, Buttons, CancelButton,
-                                  OkButton, CloseButton, PasswordLineEdit)
+                                  OkButton, CloseButton, PasswordLineEdit, getOpenFileName)
 from electrum.i18n import _
 from electrum.plugin import hook
 from electrum.util import bh2u
@@ -542,8 +542,11 @@ class SettingsDialog(WindowModalDialog):
             invoke_client('toggle_passphrase', unpair_after=currently_enabled)
 
         def change_homescreen():
-            dialog = QFileDialog(self, _("Choose Homescreen"))
-            filename, __ = dialog.getOpenFileName()
+            filename = getOpenFileName(
+                parent=self,
+                title=_("Choose Homescreen"),
+                config=config,
+            )
             if not filename:
                 return  # user cancelled