qt receive tab: rename "create onchain" btn to "New Address"

electrum/gui/qt/main_window.py

@@ -1100,7 +1100,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
 
         self.clear_invoice_button = QPushButton(_('Clear'))
         self.clear_invoice_button.clicked.connect(self.clear_receive_tab)
-        self.create_invoice_button = QPushButton(_('Request'))
+        self.create_invoice_button = QPushButton(_('New Address'))
         self.create_invoice_button.setIcon(read_QIcon("bitcoin.png"))
         self.create_invoice_button.setToolTip('Create on-chain request')
         self.create_invoice_button.clicked.connect(lambda: self.create_invoice(False))
@@ -1109,7 +1109,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
         buttons.addWidget(self.clear_invoice_button)
         buttons.addWidget(self.create_invoice_button)
         if self.wallet.has_lightning():
-            self.create_invoice_button.setText(_('On-chain'))
+            self.create_invoice_button.setText(_('New Address'))
             self.create_lightning_invoice_button = QPushButton(_('Lightning'))
             self.create_lightning_invoice_button.setToolTip('Create lightning request')
             self.create_lightning_invoice_button.setIcon(read_QIcon("lightning.png"))
@@ -1217,6 +1217,10 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
         message = self.receive_message_e.text()
         expiry = self.config.get('request_expiry', PR_DEFAULT_EXPIRATION_WHEN_CREATING)
         if is_lightning:
+            if not self.wallet.lnworker.channels:
+                self.show_error(_("You need to open a Lightning channel first."))
+                return
+            # TODO maybe show a warning if amount exceeds lnworker.num_sats_can_receive (as in kivy)
             key = self.wallet.lnworker.add_request(amount, message, expiry)
         else:
             key = self.create_bitcoin_request(amount, message, expiry)