wayland: Close layer-shell clients when associated output is disabled

When an output is disabled, it's not necessarily destroyed.

abstract_output.cpp

@@ -67,6 +67,11 @@ QByteArray AbstractOutput::uuid() const
     return QByteArray();
 }
 
+bool AbstractOutput::isEnabled() const
+{
+    return true;
+}
+
 void AbstractOutput::setEnabled(bool enable)
 {
     Q_UNUSED(enable)

abstract_output.h

@@ -103,6 +103,11 @@ public:
      */
     virtual QByteArray uuid() const;
 
+    /**
+     * Returns @c true if the output is enabled; otherwise returns @c false.
+     */
+    virtual bool isEnabled() const;
+
     /**
      * Enable or disable the output.
      *
@@ -190,6 +195,10 @@ Q_SIGNALS:
      * This signal is emitted when the geometry of this output has changed.
      */
     void geometryChanged();
+    /**
+     * This signal is emitted when the output has been enabled or disabled.
+     */
+    void enabledChanged();
 
 private:
     Q_DISABLE_COPY(AbstractOutput)

abstract_wayland_output.cpp

@@ -240,6 +240,8 @@ void AbstractWaylandOutput::setEnabled(bool enable)
         // xdg-output is destroyed in KWayland on wl_output going away.
         updateEnablement(false);
     }
+
+    emit enabledChanged();
 }
 
 QString AbstractWaylandOutput::description() const

abstract_wayland_output.h

@@ -105,7 +105,7 @@ public:
         return m_waylandOutput;
     }
 
-    bool isEnabled() const;
+    bool isEnabled() const override;
     /**
      * Enable or disable the output.
      *

layershellv1client.cpp

@@ -58,6 +58,8 @@ LayerShellV1Client::LayerShellV1Client(LayerSurfaceV1Interface *shellSurface,
 
     connect(output, &AbstractOutput::geometryChanged,
             this, &LayerShellV1Client::scheduleRearrange);
+    connect(output, &AbstractOutput::enabledChanged,
+            this, &LayerShellV1Client::handleOutputEnabledChanged);
     connect(output, &AbstractOutput::destroyed,
             this, &LayerShellV1Client::handleOutputDestroyed);
 
@@ -256,6 +258,14 @@ void LayerShellV1Client::handleAcceptsFocusChanged()
     }
 }
 
+void LayerShellV1Client::handleOutputEnabledChanged()
+{
+    if (!m_output->isEnabled()) {
+        closeWindow();
+        destroyClient();
+    }
+}
+
 void LayerShellV1Client::handleOutputDestroyed()
 {
     closeWindow();

layershellv1client.h

@@ -54,6 +54,7 @@ private:
     void handleUnmapped();
     void handleCommitted();
     void handleAcceptsFocusChanged();
+    void handleOutputEnabledChanged();
     void handleOutputDestroyed();
     void scheduleRearrange();