Require the cursor to move a minimum distance after the mouse press before initiating a mouse drag.

The CL also makes ShelfViewTest send ui::MouseEvents in the coordinates of |ShelfView::drag_view_|.

BUG=377522
TEST=ShelfViewTest.ClickAndMoveSlightly

Review URL: https://codereview.chromium.org/338833008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278129 0039d316-1c4b-4281-b951-d872f2087c98

ash/shelf/shelf_view.cc

@@ -376,7 +376,6 @@ ShelfView::ShelfView(ShelfModel* model,
       owner_overflow_bubble_(NULL),
       drag_pointer_(NONE),
       drag_view_(NULL),
-      drag_offset_(0),
       start_drag_index_(-1),
       context_menu_id_(0),
       leading_inset_(kDefaultLeadingInset),
@@ -968,7 +967,7 @@ void ShelfView::ContinueDrag(const ui::LocatedEvent& event) {
   int x = 0, y = 0;
   if (layout_manager_->IsHorizontalAlignment()) {
     x = std::max(view_model_->ideal_bounds(indices.first).x(),
-                     drag_point.x() - drag_offset_);
+                     drag_point.x() - drag_origin_.x());
     x = std::min(view_model_->ideal_bounds(last_drag_index).right() -
                  view_model_->ideal_bounds(current_index).width(),
                  x);
@@ -977,7 +976,7 @@ void ShelfView::ContinueDrag(const ui::LocatedEvent& event) {
     drag_view_->SetX(x);
   } else {
     y = std::max(view_model_->ideal_bounds(indices.first).y(),
-                     drag_point.y() - drag_offset_);
+                     drag_point.y() - drag_origin_.y());
     y = std::min(view_model_->ideal_bounds(last_drag_index).bottom() -
                  view_model_->ideal_bounds(current_index).height(),
                  y);
@@ -1576,7 +1575,7 @@ void ShelfView::PointerPressedOnButton(views::View* view,
     return;  // View is being deleted or not draggable, ignore request.
 
   drag_view_ = view;
-  drag_offset_ = layout_manager_->PrimaryAxisValue(event.x(), event.y());
+  drag_origin_ = gfx::Point(event.x(), event.y());
   UMA_HISTOGRAM_ENUMERATION("Ash.ShelfAlignmentUsage",
       layout_manager_->SelectValueForShelfAlignment(
           SHELF_ALIGNMENT_UMA_ENUM_VALUE_BOTTOM,
@@ -1592,8 +1591,8 @@ void ShelfView::PointerDraggedOnButton(views::View* view,
   // To prepare all drag types (moving an item in the shelf and dragging off),
   // we should check the x-axis and y-axis offset.
   if (!dragging() && drag_view_ &&
-      ((std::abs(event.x() - drag_offset_) >= kMinimumDragDistance) ||
-       (std::abs(event.y() - drag_offset_) >= kMinimumDragDistance))) {
+      ((std::abs(event.x() - drag_origin_.x()) >= kMinimumDragDistance) ||
+       (std::abs(event.y() - drag_origin_.y()) >= kMinimumDragDistance))) {
     PrepareForDrag(pointer, event);
   }
   if (drag_pointer_ == pointer)

ash/shelf/shelf_view.h

@@ -358,8 +358,8 @@ class ASH_EXPORT ShelfView : public views::View,
   // |dragging_| is set only if the mouse is dragged far enough.
   views::View* drag_view_;
 
-  // X coordinate of the mouse down event in |drag_view_|s coordinates.
-  int drag_offset_;
+  // Position of the mouse down event in |drag_view_|'s coordinates.
+  gfx::Point drag_origin_;
 
   // Index |drag_view_| was initially at.
   int start_drag_index_;

ash/shelf/shelf_view_unittest.cc

@@ -120,6 +120,32 @@ class ShelfViewIconObserverTest : public AshTestBase {
   DISALLOW_COPY_AND_ASSIGN(ShelfViewIconObserverTest);
 };
 
+// TestShelfItemDelegate which tracks whether it gets selected.
+class ShelfItemSelectionTracker : public TestShelfItemDelegate {
+ public:
+  ShelfItemSelectionTracker() : TestShelfItemDelegate(NULL), selected_(false) {
+  }
+
+  virtual ~ShelfItemSelectionTracker() {
+  }
+
+  // Returns true if the delegate was selected.
+  bool WasSelected() {
+    return selected_;
+  }
+
+  // TestShelfItemDelegate:
+  virtual bool ItemSelected(const ui::Event& event) OVERRIDE {
+    selected_ = true;
+    return false;
+  }
+
+ private:
+  bool selected_;
+
+  DISALLOW_COPY_AND_ASSIGN(ShelfItemSelectionTracker);
+};
+
 TEST_F(ShelfViewIconObserverTest, AddRemove) {
   TestShelfDelegate* shelf_delegate = TestShelfDelegate::instance();
   ASSERT_TRUE(shelf_delegate);
@@ -398,7 +424,7 @@ class ShelfViewTest : public AshTestBase {
     ShelfButtonHost* button_host = shelf_view_;
     views::View* button = test_api_->GetButton(button_index);
     ui::MouseEvent click_event(ui::ET_MOUSE_PRESSED,
-                               button->bounds().origin(),
+                               gfx::Point(),
                                button->GetBoundsInScreen().origin(), 0, 0);
     button_host->PointerPressedOnButton(button, pointer, click_event);
     return button;
@@ -421,7 +447,8 @@ class ShelfViewTest : public AshTestBase {
     // Drag.
     views::View* destination = test_api_->GetButton(destination_index);
     ui::MouseEvent drag_event(ui::ET_MOUSE_DRAGGED,
-                              destination->bounds().origin(),
+                              gfx::Point(destination->x() - button->x(),
+                                         destination->y() - button->y()),
                               destination->GetBoundsInScreen().origin(), 0, 0);
     button_host->PointerDraggedOnButton(button, pointer, drag_event);
     return button;
@@ -1030,6 +1057,54 @@ TEST_F(ShelfViewTest, ClickOneDragAnother) {
   EXPECT_TRUE(model_->items()[3].type == TYPE_BROWSER_SHORTCUT);
 }
 
+// Check that clicking an item and jittering the mouse a bit still selects the
+// item.
+TEST_F(ShelfViewTest, ClickAndMoveSlightly) {
+  std::vector<std::pair<ShelfID, views::View*> > id_map;
+  SetupForDragTest(&id_map);
+
+  ShelfID shelf_id = (id_map.begin() + 1)->first;
+  views::View* button = (id_map.begin() + 1)->second;
+
+  // Replace the ShelfItemDelegate for |shelf_id| with one which tracks whether
+  // the shelf item gets selected.
+  ShelfItemSelectionTracker* selection_tracker = new ShelfItemSelectionTracker;
+  item_manager_->SetShelfItemDelegate(
+      shelf_id,
+      scoped_ptr<ShelfItemDelegate>(selection_tracker).Pass());
+
+  gfx::Vector2d press_offset(5, 30);
+  gfx::Point press_location = gfx::Point() + press_offset;
+  gfx::Point press_location_in_screen =
+      button->GetBoundsInScreen().origin() + press_offset;
+
+  ui::MouseEvent click_event(ui::ET_MOUSE_PRESSED,
+                             press_location,
+                             press_location_in_screen,
+                             ui::EF_LEFT_MOUSE_BUTTON, 0);
+  button->OnMousePressed(click_event);
+
+  ui::MouseEvent drag_event1(ui::ET_MOUSE_DRAGGED,
+                             press_location + gfx::Vector2d(0, 1),
+                             press_location_in_screen + gfx::Vector2d(0, 1),
+                             ui::EF_LEFT_MOUSE_BUTTON, 0);
+  button->OnMouseDragged(drag_event1);
+
+  ui::MouseEvent drag_event2(ui::ET_MOUSE_DRAGGED,
+                             press_location + gfx::Vector2d(-1, 0),
+                             press_location_in_screen + gfx::Vector2d(-1, 0),
+                             ui::EF_LEFT_MOUSE_BUTTON, 0);
+  button->OnMouseDragged(drag_event2);
+
+  ui::MouseEvent release_event(ui::ET_MOUSE_RELEASED,
+                               press_location + gfx::Vector2d(-1, 0),
+                               press_location_in_screen + gfx::Vector2d(-1, 0),
+                               ui::EF_LEFT_MOUSE_BUTTON, 0);
+  button->OnMouseReleased(release_event);
+
+  EXPECT_TRUE(selection_tracker->WasSelected());
+}
+
 // Confirm that item status changes are reflected in the buttons.
 TEST_F(ShelfViewTest, ShelfItemStatus) {
   // All buttons should be visible.