add default request expiry to preferences/config

electrum/gui/qml/components/Preferences.qml

@@ -148,6 +148,18 @@ Pane {
                             }
                         }
 
+                        Label {
+                            text: qsTr('Default request expiry')
+                            Layout.fillWidth: false
+                        }
+
+                        RequestExpiryComboBox {
+                            onCurrentValueChanged: {
+                                if (activeFocus)
+                                    Config.requestExpiry = currentValue
+                            }
+                        }
+
                         Label {
                             text: qsTr('PIN')
                         }

electrum/gui/qml/components/ReceiveDetailsDialog.qml

@@ -84,26 +84,9 @@ ElDialog {
             Layout.fillWidth: false
         }
 
-        ElComboBox {
+        RequestExpiryComboBox {
             id: expires
             Layout.columnSpan: 2
-
-            textRole: 'text'
-            valueRole: 'value'
-
-            model: ListModel {
-                id: expiresmodel
-                Component.onCompleted: {
-                    // we need to fill the model like this, as ListElement can't evaluate script
-                    expiresmodel.append({'text': qsTr('10 minutes'), 'value': 10*60})
-                    expiresmodel.append({'text': qsTr('1 hour'), 'value': 60*60})
-                    expiresmodel.append({'text': qsTr('1 day'), 'value': 24*60*60})
-                    expiresmodel.append({'text': qsTr('1 week'), 'value': 7*24*60*60})
-                    expiresmodel.append({'text': qsTr('1 month'), 'value': 31*24*60*60})
-                    expiresmodel.append({'text': qsTr('Never'), 'value': 0})
-                    expires.currentIndex = 0
-                }
-            }
         }
 
         Item { width: 1; height: 1; Layout.fillWidth: true }

electrum/gui/qml/components/controls/RequestExpiryComboBox.qml

@@ -0,0 +1,36 @@
+import QtQuick 2.6
+import QtQuick.Controls 2.3
+
+import org.electrum 1.0
+
+ElComboBox {
+    id: expires
+
+    textRole: 'text'
+    valueRole: 'value'
+
+    model: ListModel {
+        id: expiresmodel
+        Component.onCompleted: {
+            // we need to fill the model like this, as ListElement can't evaluate script
+            expiresmodel.append({'text': qsTr('10 minutes'), 'value': 10*60})
+            expiresmodel.append({'text': qsTr('1 hour'), 'value': 60*60})
+            expiresmodel.append({'text': qsTr('1 day'), 'value': 24*60*60})
+            expiresmodel.append({'text': qsTr('1 week'), 'value': 7*24*60*60})
+            expiresmodel.append({'text': qsTr('1 month'), 'value': 31*24*60*60})
+            expiresmodel.append({'text': qsTr('Never'), 'value': 0})
+            expires.currentIndex = 0
+            for (let i=0; i < expiresmodel.count; i++) {
+                if (expiresmodel.get(i).value == Config.requestExpiry) {
+                    expires.currentIndex = i
+                    break
+                }
+            }
+        }
+    }
+
+    onCurrentValueChanged: {
+        if (activeFocus)
+            Config.requestExpiry = currentValue
+    }
+}

electrum/gui/qml/qeconfig.py

@@ -4,6 +4,7 @@ from decimal import Decimal
 
 from electrum.logging import get_logger
 from electrum.util import DECIMAL_POINT_DEFAULT, format_satoshis
+from electrum.invoices import PR_DEFAULT_EXPIRATION_WHEN_CREATING
 
 from .qetypes import QEAmount
 from .auth import AuthMixin, auth_protect
@@ -81,6 +82,18 @@ class QEConfig(AuthMixin, QObject):
         self.config.set_key('confirmed_only', not checked, True)
         self.spendUnconfirmedChanged.emit()
 
+    requestExpiryChanged = pyqtSignal()
+    @pyqtProperty(int, notify=requestExpiryChanged)
+    def requestExpiry(self):
+        a = self.config.get('request_expiry', PR_DEFAULT_EXPIRATION_WHEN_CREATING)
+        self._logger.debug(f'request expiry {a}')
+        return a
+
+    @requestExpiry.setter
+    def requestExpiry(self, expiry):
+        self.config.set_key('request_expiry', expiry)
+        self.requestExpiryChanged.emit()
+
     pinCodeChanged = pyqtSignal()
     @pyqtProperty(str, notify=pinCodeChanged)
     def pinCode(self):