[SMS App] Add highlighting to ConversationList view

Summary: Let the ListView use its default highlighting (did I not notice before?) and keep the currently-selected chat highlighted at all times

Test Plan:
 - Launch app
 - Use mouse or arrow keys to select a conversation. The highlight should follow the selected conversation

Reviewers: #kde_connect, apol

Reviewed By: #kde_connect, apol

Subscribers: apol, kdeconnect

Tags: #kde_connect

Differential Revision: https://phabricator.kde.org/D17612

smsapp/conversationlistmodel.cpp

@@ -67,6 +67,7 @@ void ConversationListModel::setDeviceId(const QString& deviceId)
     }
 
     m_deviceId = deviceId;
+    Q_EMIT deviceIdChanged();
 
     // This method still gets called *with a valid deviceID* when the device is not connected while the component is setting up
     // Detect that case and don't do anything.

smsapp/conversationlistmodel.h

@@ -68,7 +68,7 @@ class ConversationListModel
     : public QStandardItemModel
 {
     Q_OBJECT
-    Q_PROPERTY(QString deviceId READ deviceId WRITE setDeviceId)
+    Q_PROPERTY(QString deviceId READ deviceId WRITE setDeviceId NOTIFY deviceIdChanged)
 
 public:
     ConversationListModel(QObject* parent = nullptr);
@@ -92,6 +92,9 @@ public Q_SLOTS:
     void createRowFromMessage(const QVariantMap& message);
     void printDBusError(const QDBusError& error);
 
+Q_SIGNALS:
+    void deviceIdChanged();
+
 private:
     /**
      * Get all conversations currently known by the conversationsInterface, if any

smsapp/conversationmodel.cpp

@@ -51,7 +51,8 @@ void ConversationModel::setThreadId(const qint64& threadId)
 
     m_threadId = threadId;
     clear();
-    if (threadId != INVALID_THREAD_ID) {
+    knownMessageIDs.clear();
+    if (m_threadId != INVALID_THREAD_ID && m_deviceId != "") {
         requestMoreMessages();
     }
 }

smsapp/qml/ConversationList.qml

@@ -55,7 +55,7 @@ Kirigami.ScrollablePage
     readonly property QtObject device: devicesCombo.currentIndex >= 0 ? devicesModel.data(devicesModel.index(devicesCombo.currentIndex, 0), DevicesModel.DeviceRole) : null
     readonly property alias lastDeviceId: conversationListModel.deviceId
 
-    Component {
+    ConversationDisplay {
         id: chatView
         ConversationDisplay {
             deviceId: page.lastDeviceId
@@ -122,7 +122,17 @@ Kirigami.ScrollablePage
                                                        conversationId: model.conversationId,
                 })
             }
-            onClicked: { startChat(); }
+            onClicked: {
+                startChat();
+                view.currentIndex = index
+            }
+            // Keep the currently-open chat highlighted even if this element is not focused
+            highlighted: chatView.conversationId == model.conversationId
+        }
+
+        Component.onCompleted: {
+            currentIndex = -1
+            focus = true
         }
 
     }