Fixed problem with clicking on app launcher item

ui/app_list/views/apps_grid_view.cc

Index: ui/app_list/views/apps_grid_view.cc
diff --git a/ui/app_list/views/apps_grid_view.cc b/ui/app_list/views/apps_grid_view.cc
index dd145ca2d97536bded59c1657b1dcb958a1e1db5..92e5803155b8f48d54376d3f615be07d16a511b2 100644
--- a/ui/app_list/views/apps_grid_view.cc
+++ b/ui/app_list/views/apps_grid_view.cc
@@ -15,6 +15,7 @@
 #include "ui/app_list/views/pulsing_block_view.h"
 #include "ui/base/animation/animation.h"
 #include "ui/base/events/event.h"
+#include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/views/border.h"
 #include "ui/views/view_model_utils.h"
 #include "ui/views/widget/widget.h"
@@ -201,14 +202,19 @@ void AppsGridView::InitiateDrag(AppListItemView* view,
   // Note: This code has very likely to be changed for Windows (non metro mode)
   // when a |drag_and_drop_host_| gets implemented.
   if (drag_and_drop_host_) {
+    // Determine the mouse offset to the center of the icon so that the drag and
+    // drop host follows this layer.
+    gfx::Vector2d delta = event.root_location() -
+                          drag_view_->GetBoundsInScreen().CenterPoint();
+    delta.set_y(delta.y() + drag_view_->title()->size().height() / 2);
     // We have to hide the original item since the drag and drop host will do
     // the OS dependent code to "lift off the dragged item".
-    // Note that we cannot use SetVisible since it would remove the mouse input.
-    drag_view_->SetSize(gfx::Size());
     drag_and_drop_host_->CreateDragIconProxy(event.root_location(),
                                              view->model()->icon(),
                                              drag_view_,
+                                             delta,
                                              kDragAndDropProxyScale);
+    HideView(drag_view_, true);
   }
   drag_start_ = event.location();
 }
@@ -244,10 +250,8 @@ void AppsGridView::UpdateDrag(AppListItemView* view,
   if (last_drop_target != drop_target_)
     AnimateToIdealBounds();
 
-  if (drag_and_drop_host_) {
+  if (drag_and_drop_host_)
     drag_and_drop_host_->UpdateDragIconProxy(event.root_location());
-    return;
-  }
 
   drag_view_->SetPosition(
       gfx::PointAtOffsetFromOrigin(last_drag_point_ - drag_start_));
@@ -263,14 +267,11 @@ void AppsGridView::EndDrag(bool cancel) {
       MoveItemInModel(drag_view_, drop_target_);
   }
 
-  // In case we had a drag and drop proxy icon, we delete it and make the real
-  // item visible again.
   if (drag_and_drop_host_) {
+    // If we had a drag and drop proxy icon, we delete it and make the real
+    // item visible again.
     drag_and_drop_host_->DestroyDragIconProxy();
-    // To avoid an incorrect animation on re-group, |drag_view_| gets positioned
-    // at its last known drag location.
-    drag_view_->SetPosition(
-        gfx::PointAtOffsetFromOrigin(last_drag_point_ - drag_start_));
+    HideView(drag_view_, false);
   }
 
   drag_pointer_ = NONE;
@@ -919,4 +920,10 @@ void AppsGridView::OnAppListModelStatusChanged() {
   SchedulePaint();
 }
 
+void AppsGridView::HideView(views::View* view, bool hide) {
+  ui::ScopedLayerAnimationSettings animator(view->layer()->GetAnimator());
+  animator.SetPreemptionStrategy(ui::LayerAnimator::IMMEDIATELY_SET_NEW_TARGET);
+  view->layer()->SetOpacity(hide ? 0 : 1);

[xiyuan, 2013/05/31 23:06:17]

This would not compile on win bots since they might not USE_AURA and thus not
having layers.

[Mr4D (OOO till 08-26), 2013/05/31 23:32:20]

Done.

+}
+
 }  // namespace app_list