Render shelf as if disabled during connection process

Instead of displaying nothing (i.e. the unobscured window background
behind the shelf), render the shelf as if disabled before we have a
connection and initial data.

Going from disabled to the true state is less jarring and visually
more pleasing than briefly flashing white.

src/declarative/Gui.qml

@@ -113,7 +113,7 @@ Window {
         anchors.top: parent.top
         anchors.right: parent.right
 
-        active: !Startup.onboard && (!gui.model.connected
+        active: !Startup.onboard && (!gui.model.ready
             || NetworkInformation.reachability === NetworkInformation.Reachability.Disconnected)
         sourceComponent: connectionStatusComponent
     }
@@ -149,11 +149,26 @@ Window {
 
             enabled: (curtain && curtain.open) || !curtain
 
-            // Unset to avoid unnecessary busy work while the display is off.
-            model: (curtain && curtain.open || !curtain) ? gui.model : null
+            model: {
+                // Unset to avoid unnecessary busy work while the display is off.
+                if (curtain && curtain.open || !curtain) {
+                    // If we're acting as a client to a remote instance but aren't
+                    // ready to render actual data yet, render the shelf visualization
+                    // as if the shelf is disabled. This is visually more pleasing at
+                    // startup instead of briefly flashing the white background before
+                    // the true state streams in.
+                    if (!Startup.onboard && !gui.model.ready) {
+                        return Settings.rows * Settings.columns;
+                    }
+
+                    return gui.model;
+                }
+
+                return null;
+            }
 
-            rows: model ? model.rows : 0
-            columns: model ? model.columns : 0
+            rows: Qt.isQtObject(model) ? model.rows : Settings.rows
+            columns: Qt.isQtObject(model) ? model.columns : Settings.columns
 
             onTapped: function (square) {
                 if (displayController) {

src/remoteshelfmodel.cpp

@@ -30,11 +30,6 @@ RemoteShelfModel::~RemoteShelfModel()
 {
 }
 
-bool RemoteShelfModel::connected() const
-{
-    return m_remoteModelIface && (m_remoteModelIface->state() == QRemoteObjectReplica::Valid);
-}
-
 QUrl RemoteShelfModel::serverAddress() const
 {
     return m_serverAddress;
@@ -53,6 +48,13 @@ void RemoteShelfModel::setServerAddress(const QUrl &url)
     }
 }
 
+bool RemoteShelfModel::ready() const
+{
+    return m_remoteModelIface
+        && m_remoteModel->isInitialized()
+        && (m_remoteModelIface->state() == QRemoteObjectReplica::Valid);
+}
+
 bool RemoteShelfModel::enabled() const
 {
     if (!m_remoteModelIface || !m_remoteModelIface->isInitialized()) {
@@ -277,7 +279,7 @@ void RemoteShelfModel::updateSource()
         delete m_remotingServer;
         m_remotingServer = nullptr;
 
-        Q_EMIT connectedChanged();
+        Q_EMIT readyChanged();
 
         Q_EMIT enabledChanged();
 
@@ -324,6 +326,9 @@ void RemoteShelfModel::updateSource()
             return;
         }
 
+        QObject::connect(m_remoteModel, &QAbstractItemModelReplica::initialized,
+            this, &RemoteShelfModel::readyChanged);
+
         setSourceModel(m_remoteModel);
 
         m_remoteModelIface =  m_remotingServer->acquire<RemoteShelfModelIfaceReplica>();
@@ -334,10 +339,10 @@ void RemoteShelfModel::updateSource()
             return;
         }
 
-        Q_EMIT connectedChanged();
+        Q_EMIT readyChanged();
 
         QObject::connect(m_remoteModelIface, &QRemoteObjectReplica::stateChanged,
-            this, &RemoteShelfModel::connectedChanged);
+            this, &RemoteShelfModel::readyChanged);
 
         qCInfo(HYELICHT_REMOTING) << i18n("Connected to remoting API server at: %1",
             m_serverAddress.toString());

src/remoteshelfmodel.h

@@ -39,13 +39,6 @@ class RemoteShelfModel : public QIdentityProxyModel, public QQmlParserStatus
     Q_OBJECT
     Q_INTERFACES(QQmlParserStatus)
 
-    //! Whether there is a healthy connection to a ShelfModel.
-    /*!
-    *
-    * \sa serverAddress
-    */
-    Q_PROPERTY(bool connected READ connected NOTIFY connectedChanged)
-
     //! Address used to connect to a ShelfModel instance.
     /*!
     * Can be e.g. \c tcp:// or \c local:.
@@ -57,6 +50,13 @@ class RemoteShelfModel : public QIdentityProxyModel, public QQmlParserStatus
     */
     Q_PROPERTY(QUrl serverAddress READ serverAddress WRITE setServerAddress NOTIFY serverAddressChanged)
 
+    //! Whether the connection is healthy and remote data is available.
+    /*!
+    *
+    * \sa serverAddress
+    */
+    Q_PROPERTY(bool ready READ ready NOTIFY readyChanged)
+
     //! \sa ShelfModel::enabled
     Q_PROPERTY(bool enabled READ enabled WRITE setEnabled NOTIFY enabledChanged)
 
@@ -95,13 +95,6 @@ class RemoteShelfModel : public QIdentityProxyModel, public QQmlParserStatus
         explicit RemoteShelfModel(QObject *parent = nullptr);
         ~RemoteShelfModel() override;
 
-        //! Whether there is a healthy connection to a ShelfModel.
-        /*!
-        * @return Connected or not.
-        * \sa serverAddress
-        */
-        bool connected() const;
-
         //! The address used to connect to a ShelfModel instance.
         /*!
         * @return Server address, e.g. \c tcp:// or \c local:.
@@ -119,6 +112,13 @@ class RemoteShelfModel : public QIdentityProxyModel, public QQmlParserStatus
         */
         void setServerAddress(const QUrl &url);
 
+        //! Whether the connection is healthy and remote data is available.
+        /*!
+        * @return Ready or not.
+        * \sa serverAddress
+        */
+        bool ready() const;
+
         //! \sa ShelfModel::enabled
         bool enabled() const;
         //! \sa ShelfModel::setEnabled
@@ -179,11 +179,11 @@ class RemoteShelfModel : public QIdentityProxyModel, public QQmlParserStatus
         void componentComplete() override;
 
     Q_SIGNALS:
-        //! Whether there is a healthy connection to a ShelfModel has changed.
+        //! Whether the connection is healthy and remote data is available.
         /*!
-        * \sa connected
+        * \sa ready
         */
-        void connectedChanged() const;
+        void readyChanged() const;
 
         //! The address used to connect to a ShelfModel instance has changed.
         /*!