qml: expose LIGHTNING_PAYMENT_BUDGET_FEE_MAX_MILLIONTHS in preferences

electrum/gui/qml/components/Preferences.qml

@@ -258,6 +258,42 @@ Pane {
                         text: qsTr('Lightning')
                     }
 
+                    Label {
+                        Layout.fillWidth: true
+                        text: Config.shortDescFor('LIGHTNING_PAYMENT_FEE_MAX_MILLIONTHS')
+                        wrapMode: Text.Wrap
+                    }
+
+                    Label {
+                        Layout.fillWidth: true
+                        text: qsTr('<b>%1%</b> of payment').arg(maxfeeslider._fees[maxfeeslider.value]/10000)
+                        wrapMode: Text.Wrap
+                    }
+
+                    Slider {
+                        id: maxfeeslider
+                        Layout.columnSpan: 2
+                        Layout.fillWidth: true
+                        Layout.leftMargin: constants.paddingXLarge
+                        Layout.rightMargin: constants.paddingXLarge
+
+                        property var _fees: [500, 1000, 3000, 5000, 10000, 20000, 30000, 50000]
+
+                        snapMode: Slider.SnapOnRelease
+                        stepSize: 1
+                        from: 0
+                        to: _fees.length - 1
+
+                        onValueChanged: {
+                            if (activeFocus)
+                                Config.lightningPaymentFeeMaxMillionths = _fees[value]
+                        }
+
+                        Component.onCompleted: {
+                            value = _fees.indexOf(Config.lightningPaymentFeeMaxMillionths)
+                        }
+                    }
+
                     RowLayout {
                         Layout.columnSpan: 2
                         Layout.fillWidth: true

electrum/gui/qml/qeconfig.py

@@ -23,6 +23,16 @@ class QEConfig(AuthMixin, QObject):
         super().__init__(parent)
         self.config = config
 
+    @pyqtSlot(str, result=str)
+    def shortDescFor(self, key) -> str:
+        cv = getattr(self.config.cv, key)
+        return cv.get_short_desc() if cv else ''
+
+    @pyqtSlot(str, result=str)
+    def longDescFor(self, key) -> str:
+        cv = getattr(self.config.cv, key)
+        return cv.get_long_desc() if cv else ''
+
     languageChanged = pyqtSignal()
     @pyqtProperty(str, notify=languageChanged)
     def language(self):
@@ -255,6 +265,17 @@ class QEConfig(AuthMixin, QObject):
             self.config.WALLET_COIN_CHOOSER_OUTPUT_ROUNDING = outputValueRounding
             self.outputValueRoundingChanged.emit()
 
+    lightningPaymentFeeMaxMillionthsChanged = pyqtSignal()
+    @pyqtProperty(int, notify=lightningPaymentFeeMaxMillionthsChanged)
+    def lightningPaymentFeeMaxMillionths(self):
+        return self.config.LIGHTNING_PAYMENT_FEE_MAX_MILLIONTHS
+
+    @lightningPaymentFeeMaxMillionths.setter
+    def lightningPaymentFeeMaxMillionths(self, lightningPaymentFeeMaxMillionths):
+        if lightningPaymentFeeMaxMillionths != self.config.LIGHTNING_PAYMENT_FEE_MAX_MILLIONTHS:
+            self.config.LIGHTNING_PAYMENT_FEE_MAX_MILLIONTHS = lightningPaymentFeeMaxMillionths
+            self.lightningPaymentFeeMaxMillionthsChanged.emit()
+
     @pyqtSlot('qint64', result=str)
     @pyqtSlot(QEAmount, result=str)
     def formatSatsForEditing(self, satoshis):