qml: show channel close tx(id) in ChannelDetails

electrum/gui/qml/components/ChannelDetails.qml

@@ -323,6 +323,50 @@ Pane {
                         }
                     }
 
+                    Label {
+                        Layout.columnSpan: 2
+                        Layout.topMargin: constants.paddingSmall
+                        visible: channeldetails.closingTxid
+                        text: qsTr('Closing transaction')
+                        color: Material.accentColor
+                    }
+
+                    TextHighlightPane {
+                        Layout.columnSpan: 2
+                        Layout.fillWidth: true
+                        visible: channeldetails.closingTxid
+
+                        RowLayout {
+                            width: parent.width
+                            Label {
+                                text: channeldetails.closingTxid
+                                font.pixelSize: constants.fontSizeLarge
+                                font.family: FixedFont
+                                Layout.fillWidth: true
+                                wrapMode: Text.Wrap
+
+                                TapHandler {
+                                    onTapped: {
+                                        app.stack.push(Qt.resolvedUrl('TxDetails.qml'), {
+                                            txid: channeldetails.closingTxid
+                                        })
+                                    }
+                                }
+                            }
+                            ToolButton {
+                                icon.source: '../../icons/share.png'
+                                icon.color: 'transparent'
+                                onClicked: {
+                                    var dialog = app.genericShareDialog.createObject(root, {
+                                        title: qsTr('Channel close transaction'),
+                                        text: channeldetails.closingTxid
+                                    })
+                                    dialog.open()
+                                }
+                            }
+                        }
+                    }
+
                 }
             }
         }

electrum/gui/qml/qechanneldetails.py

@@ -121,6 +121,17 @@ class QEChannelDetails(AuthMixin, QObject, QtEventListener):
             'index': outpoint.output_index
         }
 
+    @pyqtProperty(str, notify=channelChanged)
+    def closingTxid(self):
+        if not self._channel.is_closed():
+            return ''
+        item = self._channel.get_closing_height()
+        if item:
+            closing_txid, closing_height, timestamp = item
+            return closing_txid
+        else:
+            return ''
+
     @pyqtProperty(QEAmount, notify=channelChanged)
     def capacity(self):
         self._capacity.copyFrom(QEAmount(amount_sat=self._channel.get_capacity()))