app_list: Add touch drag-n-drop.

- Use a 200ms timer to start touch drag;
- Add 150% scale when touch drag starts;

Also fix a problem that dragged icon goes off when page transition animation
calls Layout() with running BoundsAnimator animation.

BUG=117090
TEST=Verify could use touch to reorder apps in app list.

R=sky@chromium.org,sadrul@chromium.org


Review URL: https://chromiumcodereview.appspot.com/11196011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@162630 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 176 insertions, 37 deletions

diff --git a/ui/app_list/app_list_item_view.cc b/ui/app_list/app_list_item_view.cc
index 6db3fb6..f4f9bd9 100644
--- a/ui/app_list/app_list_item_view.cc
+++ b/ui/app_list/app_list_item_view.cc
@@ -12,9 +12,12 @@
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/animation/throb_animation.h"
 #include "ui/base/resource/resource_bundle.h"
+#include "ui/compositor/layer.h"
+#include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/font.h"
 #include "ui/gfx/image/image_skia_operations.h"
+#include "ui/gfx/transform_util.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/controls/menu/menu_item_view.h"
@@ -39,6 +42,12 @@ const SkColor kHighlightedColor = kHoverAndPushedColor;
 const int kTitleFontSize = 11;
 const int kLeftRightPaddingChars = 1;
 
+// Delay in milliseconds of when a touch drag should start after tap down.
+const int kTouchDragStartDelayInMs = 100;
+
+// Scale to transform when touch drag starts.
+const float kTouchDraggingScale = 1.5f;
+
 const gfx::Font& GetTitleFont() {
   static gfx::Font* font = NULL;
 
@@ -65,7 +74,8 @@ AppListItemView::AppListItemView(AppsGridView* apps_grid_view,
       model_(model),
       apps_grid_view_(apps_grid_view),
       icon_(new views::ImageView),
-      title_(new views::Label) {
+      title_(new views::Label),
+      touch_dragging_(false) {
   icon_->set_interactive(false);
 
   title_->SetBackgroundColor(0);
@@ -121,6 +131,31 @@ void AppListItemView::UpdateIcon() {
   icon_->SetImage(shadow);
 }
 
+void AppListItemView::OnTouchDragTimer() {
+  SetTouchDragging(true);
+}
+
+void AppListItemView::SetTouchDragging(bool touch_dragging) {
+  if (touch_dragging_ == touch_dragging)
+    return;
+
+  touch_dragging_ = touch_dragging;
+
+#if !defined(OS_WIN)
+  ui::ScopedLayerAnimationSettings settings(layer()->GetAnimator());
+  if (touch_dragging_) {
+    title_->SetVisible(false);
+    const gfx::Rect bounds(layer()->bounds().size());
+    layer()->SetTransform(gfx::GetScaleTransform(
+        bounds.CenterPoint(),
+        kTouchDraggingScale));
+  } else {
+    title_->SetVisible(true);
+    layer()->SetTransform(gfx::Transform());
+  }
+#endif
+}
+
 void AppListItemView::ItemIconChanged() {
   UpdateIcon();
 }
@@ -221,7 +256,7 @@ bool AppListItemView::ShouldEnterPushedState(const ui::Event& event) {
 
 bool AppListItemView::OnMousePressed(const ui::MouseEvent& event) {
   CustomButton::OnMousePressed(event);
-  apps_grid_view_->InitiateDrag(this, event);
+  apps_grid_view_->InitiateDrag(this, AppsGridView::MOUSE, event);
   return true;
 }
 
@@ -237,8 +272,49 @@ void AppListItemView::OnMouseCaptureLost() {
 
 bool AppListItemView::OnMouseDragged(const ui::MouseEvent& event) {
   CustomButton::OnMouseDragged(event);
-  apps_grid_view_->UpdateDrag(this, event);
+  apps_grid_view_->UpdateDrag(this, AppsGridView::MOUSE, event);
   return true;
 }
 
+ui::EventResult AppListItemView::OnGestureEvent(
+    const ui::GestureEvent& event) {
+  switch (event.type()) {
+    case ui::ET_GESTURE_TAP_DOWN:
+      touch_drag_timer_.Start(FROM_HERE,
+         base::TimeDelta::FromMilliseconds(kTouchDragStartDelayInMs),
+         this, &AppListItemView::OnTouchDragTimer);
+      break;
+    case ui::ET_GESTURE_SCROLL_BEGIN:
+      if (touch_dragging_) {
+        apps_grid_view_->InitiateDrag(this, AppsGridView::TOUCH, event);
+        return ui::ER_CONSUMED;
+      } else {
+        touch_drag_timer_.Stop();
+      }
+      break;
+    case ui::ET_GESTURE_SCROLL_UPDATE:
+      if (touch_dragging_) {
+        apps_grid_view_->UpdateDrag(this, AppsGridView::TOUCH, event);
+        return ui::ER_CONSUMED;
+      }
+      break;
+    case ui::ET_GESTURE_SCROLL_END:
+    case ui::ET_SCROLL_FLING_START:
+      if (touch_dragging_) {
+        SetTouchDragging(false);
+        apps_grid_view_->EndDrag(false);
+        return ui::ER_CONSUMED;
+      }
+      break;
+    case ui::ET_GESTURE_END:
+    case ui::ET_GESTURE_LONG_PRESS:
+      touch_drag_timer_.Stop();
+      SetTouchDragging(false);
+      break;
+    default:
+      break;
+  }
+  return CustomButton::OnGestureEvent(event);
+}
+
 }  // namespace app_list
diff --git a/ui/app_list/app_list_item_view.h b/ui/app_list/app_list_item_view.h
index 2f057b64..92e90b3 100644
--- a/ui/app_list/app_list_item_view.h
+++ b/ui/app_list/app_list_item_view.h
@@ -9,6 +9,7 @@
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/timer.h"
 #include "ui/app_list/app_list_export.h"
 #include "ui/app_list/app_list_item_model_observer.h"
 #include "ui/gfx/shadow_value.h"
@@ -46,6 +47,13 @@ class APP_LIST_EXPORT AppListItemView : public views::CustomButton,
   // Get icon from model and schedule background processing.
   void UpdateIcon();
 
+  // Invoked when |touch_drag_timer_| fires. It sets touch dragging flag so
+  // that further touch scroll gestures contribute to drag.
+  void OnTouchDragTimer();
+
+  // Sets |touch_dragging_| flag and updates UI.
+  void SetTouchDragging(bool touch_dragging);
+
   // AppListItemModelObserver overrides:
   virtual void ItemIconChanged() OVERRIDE;
   virtual void ItemTitleChanged() OVERRIDE;
@@ -70,6 +78,8 @@ class APP_LIST_EXPORT AppListItemView : public views::CustomButton,
   virtual void OnMouseReleased(const ui::MouseEvent& event) OVERRIDE;
   virtual void OnMouseCaptureLost() OVERRIDE;
   virtual bool OnMouseDragged(const ui::MouseEvent& event) OVERRIDE;
+  virtual ui::EventResult OnGestureEvent(
+      const ui::GestureEvent& event) OVERRIDE;
 
   AppListItemModel* model_;  // Owned by AppListModel::Apps.
 
@@ -82,6 +92,14 @@ class APP_LIST_EXPORT AppListItemView : public views::CustomButton,
   gfx::Size icon_size_;
   gfx::ShadowValues icon_shadows_;
 
+  // A timer to track whether user has pressed on the item long enough. When it
+  // fires, subsequent scroll gesture events will contribute to drag instead
+  // scrolling.
+  base::OneShotTimer<AppListItemView> touch_drag_timer_;
+
+  // True if scroll gestures should contribute to dragging.
+  bool touch_dragging_;
+
   DISALLOW_COPY_AND_ASSIGN(AppListItemView);
 };
 
diff --git a/ui/app_list/apps_grid_view.cc b/ui/app_list/apps_grid_view.cc
index 34dac77..96fc4e5 100644
--- a/ui/app_list/apps_grid_view.cc
+++ b/ui/app_list/apps_grid_view.cc
@@ -49,7 +49,7 @@ AppsGridView::AppsGridView(AppsGridViewDelegate* delegate,
       rows_per_page_(0),
       selected_view_(NULL),
       drag_view_(NULL),
-      dragging_(false),
+      drag_pointer_(NONE),
       page_flip_target_(-1),
       page_flip_delay_in_ms_(kPageFlipDelayInMs),
       ALLOW_THIS_IN_INITIALIZER_LIST(bounds_animator_(this)) {
@@ -112,6 +112,7 @@ void AppsGridView::EnsureViewVisible(const views::View* view) {
 }
 
 void AppsGridView::InitiateDrag(views::View* view,
+                                Pointer pointer,
                                 const ui::LocatedEvent& event) {
   if (drag_view_)
     return;
@@ -121,16 +122,17 @@ void AppsGridView::InitiateDrag(views::View* view,
 }
 
 void AppsGridView::UpdateDrag(views::View* view,
+                              Pointer pointer,
                               const ui::LocatedEvent& event) {
-  if (!dragging_ && drag_view_ &&
+  if (!dragging() && drag_view_ &&
       ExceededDragThreshold(event.x() - drag_offset_.x(),
                             event.y() - drag_offset_.y())) {
-    dragging_ = true;
+    drag_pointer_ = pointer;
     // Move the view to the front so that it appears on top of other views.
     ReorderChildView(drag_view_, -1);
     bounds_animator_.StopAnimatingView(drag_view_);
   }
-  if (dragging_) {
+  if (drag_pointer_ == pointer) {
     last_drag_point_ = event.location();
     views::View::ConvertPointToTarget(drag_view_, this, &last_drag_point_);
 
@@ -143,16 +145,15 @@ void AppsGridView::UpdateDrag(views::View* view,
     page_switcher_view_->UpdateUIForDragPoint(page_switcher_point);
 
     AnimateToIdealBounds();
-    bounds_animator_.StopAnimatingView(drag_view_);
     drag_view_->SetPosition(last_drag_point_.Subtract(drag_offset_));
   }
 }
 
 void AppsGridView::EndDrag(bool cancel) {
-  if (!cancel && dragging_ && drag_view_ && IsValidIndex(drop_target_))
+  if (!cancel && dragging() && drag_view_ && IsValidIndex(drop_target_))
     MoveItemInModel(drag_view_, drop_target_);
 
-  dragging_ = false;
+  drag_pointer_ = NONE;
   drop_target_ = Index();
   if (drag_view_) {
     drag_view_ = NULL;
@@ -180,15 +181,14 @@ gfx::Size AppsGridView::GetPreferredSize() {
 }
 
 void AppsGridView::Layout() {
-  if (bounds_animator_.IsAnimating()) {
-    AnimateToIdealBounds();
-  } else {
-    CalculateIdealBounds();
-    for (int i = 0; i < view_model_.view_size(); ++i) {
-      views::View* view = view_model_.view_at(i);
-      if (view != drag_view_)
-        view->SetBoundsRect(view_model_.ideal_bounds(i));
-    }
+  if (bounds_animator_.IsAnimating())
+    bounds_animator_.Cancel();
+
+  CalculateIdealBounds();
+  for (int i = 0; i < view_model_.view_size(); ++i) {
+    views::View* view = view_model_.view_at(i);
+    if (view != drag_view_)
+      view->SetBoundsRect(view_model_.ideal_bounds(i));
   }
 
   const int page_switcher_height =
@@ -412,8 +412,11 @@ void AppsGridView::CalculateIdealBounds() {
 void AppsGridView::AnimateToIdealBounds() {
   CalculateIdealBounds();
   for (int i = 0; i < view_model_.view_size(); ++i) {
-    bounds_animator_.AnimateViewTo(view_model_.view_at(i),
-                                   view_model_.ideal_bounds(i));
+    views::View* view = view_model_.view_at(i);
+    if (view != drag_view_) {
+      bounds_animator_.AnimateViewTo(view,
+                                     view_model_.ideal_bounds(i));
+    }
   }
 }
 
@@ -511,7 +514,7 @@ void AppsGridView::MoveItemInModel(views::View* item_view,
 
 void AppsGridView::ButtonPressed(views::Button* sender,
                                  const ui::Event& event) {
-  if (dragging_)
+  if (dragging())
     return;
 
   if (sender->GetClassName() != AppListItemView::kViewClassName)
@@ -525,7 +528,6 @@ void AppsGridView::ButtonPressed(views::Button* sender,
 
 void AppsGridView::ListItemsAdded(size_t start, size_t count) {
   EndDrag(true);
-  bounds_animator_.Cancel();
 
   for (size_t i = start; i < start + count; ++i) {
     views::View* view = CreateViewForItemAtIndex(i);
@@ -541,7 +543,6 @@ void AppsGridView::ListItemsAdded(size_t start, size_t count) {
 
 void AppsGridView::ListItemsRemoved(size_t start, size_t count) {
   EndDrag(true);
-  bounds_animator_.Cancel();
 
   for (size_t i = 0; i < count; ++i) {
     views::View* view = view_model_.view_at(start);
@@ -571,7 +572,7 @@ void AppsGridView::TotalPagesChanged() {
 }
 
 void AppsGridView::SelectedPageChanged(int old_selected, int new_selected) {
-  if (dragging_ && drag_view_) {
+  if (dragging()) {
     CalculateDropTarget(last_drag_point_);
     Layout();
     MaybeStartPageFlipTimer(last_drag_point_);
diff --git a/ui/app_list/apps_grid_view.h b/ui/app_list/apps_grid_view.h
index ccbad1b..31f1cdd 100644
--- a/ui/app_list/apps_grid_view.h
+++ b/ui/app_list/apps_grid_view.h
@@ -40,6 +40,12 @@ class APP_LIST_EXPORT AppsGridView : public views::View,
                                      public ui::ListModelObserver,
                                      public PaginationModelObserver {
  public:
+  enum Pointer {
+    NONE,
+    MOUSE,
+    TOUCH,
+  };
+
   AppsGridView(AppsGridViewDelegate* delegate,
                PaginationModel* pagination_model);
   virtual ~AppsGridView();
@@ -59,8 +65,12 @@ class APP_LIST_EXPORT AppsGridView : public views::View,
   // transition, this does not thing.
   void EnsureViewVisible(const views::View* view);
 
-  void InitiateDrag(views::View* view, const ui::LocatedEvent& event);
-  void UpdateDrag(views::View* view, const ui::LocatedEvent& event);
+  void InitiateDrag(views::View* view,
+                    Pointer pointer,
+                    const ui::LocatedEvent& event);
+  void UpdateDrag(views::View* view,
+                  Pointer pointer,
+                  const ui::LocatedEvent& event);
   void EndDrag(bool cancel);
   bool IsDraggedView(const views::View* view) const;
 
@@ -90,6 +100,7 @@ class APP_LIST_EXPORT AppsGridView : public views::View,
   };
 
   int tiles_per_page() const { return cols_ * rows_per_page_; }
+  bool dragging() const { return drag_pointer_ != NONE; }
 
   // Updates from model.
   void Update();
@@ -155,7 +166,7 @@ class APP_LIST_EXPORT AppsGridView : public views::View,
 
   views::View* drag_view_;
   gfx::Point drag_offset_;
-  bool dragging_;
+  Pointer drag_pointer_;
   Index drop_target_;
 
   gfx::Point last_drag_point_;
diff --git a/ui/app_list/apps_grid_view_unittest.cc b/ui/app_list/apps_grid_view_unittest.cc
index 4d234b2..ccc7f5c 100644
--- a/ui/app_list/apps_grid_view_unittest.cc
+++ b/ui/app_list/apps_grid_view_unittest.cc
@@ -164,7 +164,9 @@ class AppsGridViewTest : public testing::Test {
   }
 
   // Points are in |apps_grid_view_|'s coordinates.
-  void SimulateDrag(const gfx::Point& from, const gfx::Point& to) {
+  void SimulateDrag(AppsGridView::Pointer pointer,
+                    const gfx::Point& from,
+                    const gfx::Point& to) {
     AppListItemView* view = GetItemViewForPoint(from);
     DCHECK(view);
 
@@ -173,11 +175,11 @@ class AppsGridViewTest : public testing::Test {
 
     ui::MouseEvent pressed_event(ui::ET_MOUSE_PRESSED,
                                  translated_from, translated_from, 0);
-    apps_grid_view_->InitiateDrag(view, pressed_event);
+    apps_grid_view_->InitiateDrag(view, pointer, pressed_event);
 
     ui::MouseEvent drag_event(ui::ET_MOUSE_DRAGGED,
                               translated_to, translated_to, 0);
-    apps_grid_view_->UpdateDrag(view, drag_event);
+    apps_grid_view_->UpdateDrag(view, pointer, drag_event);
   }
 
   scoped_ptr<AppListModel::Apps> apps_model_;
@@ -252,21 +254,21 @@ TEST_F(AppsGridViewTest, MouseDrag) {
   gfx::Point to = GetItemTileRectAt(0, 1).CenterPoint();
 
   // Dragging changes model order.
-  SimulateDrag(from, to);
+  SimulateDrag(AppsGridView::MOUSE, from, to);
   apps_grid_view_->EndDrag(false);
   EXPECT_EQ(std::string("Item 1,Item 0,Item 2,Item 3"),
             GetModelContent());
   test_api_->LayoutToIdealBounds();
 
   // Canceling drag should keep existing order.
-  SimulateDrag(from, to);
+  SimulateDrag(AppsGridView::MOUSE, from, to);
   apps_grid_view_->EndDrag(true);
   EXPECT_EQ(std::string("Item 1,Item 0,Item 2,Item 3"),
             GetModelContent());
   test_api_->LayoutToIdealBounds();
 
   // Deleting an item keeps remaining intact.
-  SimulateDrag(from, to);
+  SimulateDrag(AppsGridView::MOUSE, from, to);
   apps_model_->DeleteAt(1);
   apps_grid_view_->EndDrag(false);
   EXPECT_EQ(std::string("Item 1,Item 2,Item 3"),
@@ -274,7 +276,7 @@ TEST_F(AppsGridViewTest, MouseDrag) {
   test_api_->LayoutToIdealBounds();
 
   // Adding a launcher item cancels the drag and respects the order.
-  SimulateDrag(from, to);
+  SimulateDrag(AppsGridView::MOUSE, from, to);
   apps_model_->Add(CreateItem(std::string("Extra")));
   apps_grid_view_->EndDrag(false);
   EXPECT_EQ(std::string("Item 1,Item 2,Item 3,Extra"),
@@ -299,7 +301,7 @@ TEST_F(AppsGridViewTest, MouseDragFlipPage) {
                              apps_grid_view_->height() / 2);
 
   // Drag to right edge.
-  SimulateDrag(from, to);
+  SimulateDrag(AppsGridView::MOUSE, from, to);
 
   // Page should be flipped after sometime.
   EXPECT_TRUE(page_flip_waiter.Wait(100));
@@ -318,7 +320,7 @@ TEST_F(AppsGridViewTest, MouseDragFlipPage) {
   // Now drag to the left edge and test the other direction.
   to.set_x(0);
 
-  SimulateDrag(from, to);
+  SimulateDrag(AppsGridView::MOUSE, from, to);
 
   EXPECT_TRUE(page_flip_waiter.Wait(100));
   EXPECT_EQ(1, pagination_model_->selected_page());
@@ -331,5 +333,36 @@ TEST_F(AppsGridViewTest, MouseDragFlipPage) {
   apps_grid_view_->EndDrag(true);
 }
 
+TEST_F(AppsGridViewTest, SimultaneousDrag) {
+  const int kTotalItems = 4;
+  PopulateApps(kTotalItems);
+  EXPECT_EQ(std::string("Item 0,Item 1,Item 2,Item 3"),
+            GetModelContent());
+
+  gfx::Point mouse_from = GetItemTileRectAt(0, 0).CenterPoint();
+  gfx::Point mouse_to = GetItemTileRectAt(0, 1).CenterPoint();
+
+  gfx::Point touch_from = GetItemTileRectAt(1, 0).CenterPoint();
+  gfx::Point touch_to = GetItemTileRectAt(1, 1).CenterPoint();
+
+  // Starts a mouse drag first then a touch drag.
+  SimulateDrag(AppsGridView::MOUSE, mouse_from, mouse_to);
+  SimulateDrag(AppsGridView::TOUCH, touch_from, touch_to);
+  // Finishes the drag and mouse drag wins.
+  apps_grid_view_->EndDrag(false);
+  EXPECT_EQ(std::string("Item 1,Item 0,Item 2,Item 3"),
+            GetModelContent());
+  test_api_->LayoutToIdealBounds();
+
+  // Starts a touch drag first then a mouse drag.
+  SimulateDrag(AppsGridView::TOUCH, touch_from, touch_to);
+  SimulateDrag(AppsGridView::MOUSE, mouse_from, mouse_to);
+  // Finishes the drag and touch drag wins.
+  apps_grid_view_->EndDrag(false);
+  EXPECT_EQ(std::string("Item 1,Item 0,Item 3,Item 2"),
+            GetModelContent());
+  test_api_->LayoutToIdealBounds();
+}
+
 }  // namespace test
 }  // namespace app_list