Add done_callback

Author: leolost2605

src/Gestures/GesturePropertyTransition.vala

@@ -10,6 +10,8 @@
  * with easing without a gesture. Respects the enable animation setting.
  */
 public class Gala.GesturePropertyTransition : Object {
+    public delegate void DoneCallback ();
+
     /**
      * Emitted when all animations are finished that is when the property has reached the target value
      * either via gesture or via easing or combined.
@@ -74,10 +76,20 @@ public class Gala.GesturePropertyTransition : Object {
      * it will connect to the gesture trackers signals and animate according to the input finishing with an easing
      * to the final position. If with_gesture is false it will just ease to the {@link to_value}.
      * #this will keep itself alive until the animation finishes so it is safe to immediatly unref it after creation and calling start.
+     *
+     * @param done_callback a callback for when the transition finishes. It is guaranteed to be called exactly once.
      */
-    public void start (bool with_gesture) {
+    public void start (bool with_gesture, owned DoneCallback? done_callback = null) {
         ref ();
 
+        if (done_callback != null) {
+            ulong done_callback_handler = 0;
+            done_callback_handler = done.connect (() => {
+                done_callback ();
+                disconnect (done_callback_handler);
+            });
+        }
+
         Value current_value = {};
         actor.get_property (property, ref current_value);
 

src/Widgets/WindowClone.vala

@@ -291,9 +291,7 @@ public class Gala.WindowClone : Clutter.Actor {
         new GesturePropertyTransition (this, gesture_tracker, "width", null, (float) outer_rect.width).start (with_gesture);
         new GesturePropertyTransition (this, gesture_tracker, "height", null, (float) outer_rect.height).start (with_gesture);
         new GesturePropertyTransition (this, gesture_tracker, "shadow-opacity", (uint8) 255, (uint8) 0).start (with_gesture);
-        var opacity_transition = new GesturePropertyTransition (window_icon, gesture_tracker, "opacity", 255u, 0u);
-        opacity_transition.start (with_gesture);
-        opacity_transition.done.connect (() => {
+        new GesturePropertyTransition (window_icon, gesture_tracker, "opacity", 255u, 0u).start (with_gesture, () => {
             in_slot_animation = false;
             place_widgets (outer_rect.width, outer_rect.height, target_scale);
         });
@@ -364,9 +362,7 @@ public class Gala.WindowClone : Clutter.Actor {
         new GesturePropertyTransition (this, gesture_tracker, "width", (float) initial_width, (float) rect.width).start (with_gesture);
         new GesturePropertyTransition (this, gesture_tracker, "height", (float) initial_height, (float) rect.height).start (with_gesture);
         new GesturePropertyTransition (this, gesture_tracker, "shadow-opacity", (uint8) 0, (uint8) 255).start (with_gesture);
-        var opacity_transition = new GesturePropertyTransition (window_icon, gesture_tracker, "opacity", 0u, 255u);
-        opacity_transition.start (with_gesture);
-        opacity_transition.done.connect (() => {
+        new GesturePropertyTransition (window_icon, gesture_tracker, "opacity", 0u, 255u).start (with_gesture, () => {
             in_slot_animation = false;
             place_widgets (rect.width, rect.height, scale);
         });

src/WindowManager.vala

@@ -644,12 +644,10 @@ namespace Gala {
             }
 
             new GesturePropertyTransition (out_group, gesture_tracker, "x", 0f, 0f, dest).start (switch_workspace_with_gesture);
-            var transition = new GesturePropertyTransition (wallpaper, gesture_tracker, "x", 0f, 0f, dest);
-            transition.done.connect (() => {
+            new GesturePropertyTransition (wallpaper, gesture_tracker, "x", 0f, 0f, dest).start (switch_workspace_with_gesture, () => {
                 switch_workspace_animation_finished (direction, false, true);
                 animating_switch_workspace = false;
             });
-            transition.start (switch_workspace_with_gesture);
         }
 
         private void update_input_area () {