Refactor drag handle into its own class.

Bug: 1034168
Change-Id: I1551a4cbf59669c514f46e17919fe7e91bc7bbd1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2020561
Commit-Queue: Yulun Wu <yulunwu@chromium.org>
Auto-Submit: Yulun Wu <yulunwu@chromium.org>
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#736020}

ash/BUILD.gn

@@ -576,6 +576,8 @@ component("ash") {
     "shelf/assistant_overlay.h",
     "shelf/back_button.cc",
     "shelf/back_button.h",
+    "shelf/drag_handle.cc",
+    "shelf/drag_handle.h",
     "shelf/home_button.cc",
     "shelf/home_button.h",
     "shelf/home_button_controller.cc",

ash/shelf/drag_handle.cc

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/shelf/drag_handle.h"
+
+#include "ash/public/cpp/shelf_config.h"
+#include "ash/session/session_controller_impl.h"
+#include "ash/shell.h"
+#include "base/bind.h"
+#include "base/timer/timer.h"
+#include "ui/gfx/color_palette.h"
+
+namespace ash {
+
+namespace {
+
+// Vertical padding to make the drag handle easier to tap.
+constexpr int kVerticalClickboxPadding = 15;
+
+}  // namespace
+
+DragHandle::DragHandle(gfx::Size drag_handle_size,
+                       AshColorProvider::RippleAttributes ripple_attributes,
+                       int drag_handle_corner_radius) {
+  SetPaintToLayer(ui::LAYER_SOLID_COLOR);
+  layer()->SetColor(ripple_attributes.base_color);
+  // TODO(manucornet): Figure out why we need a manual opacity adjustment
+  // to make this color look the same as the status area highlight.
+  layer()->SetOpacity(ripple_attributes.inkdrop_opacity + 0.075);
+  layer()->SetRoundedCornerRadius(
+      {drag_handle_corner_radius, drag_handle_corner_radius,
+       drag_handle_corner_radius, drag_handle_corner_radius});
+  SetSize(drag_handle_size);
+  SetEventTargeter(std::make_unique<views::ViewTargeter>(this));
+}
+
+DragHandle::~DragHandle() = default;
+
+bool DragHandle::DoesIntersectRect(const views::View* target,
+                                   const gfx::Rect& rect) const {
+  DCHECK_EQ(target, this);
+  gfx::Rect drag_handle_bounds = target->GetLocalBounds();
+  drag_handle_bounds.set_y(drag_handle_bounds.y() - kVerticalClickboxPadding);
+  drag_handle_bounds.set_height(drag_handle_bounds.height() +
+                                2 * kVerticalClickboxPadding);
+  return drag_handle_bounds.Intersects(rect);
+}
+
+}  // namespace ash

ash/shelf/drag_handle.h

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ASH_SHELF_DRAG_HANDLE_H_
+#define ASH_SHELF_DRAG_HANDLE_H_
+
+#include "ash/ash_export.h"
+#include "ash/shelf/shelf_widget.h"
+#include "ash/style/ash_color_provider.h"
+#include "base/timer/timer.h"
+#include "ui/views/view.h"
+#include "ui/views/view_targeter_delegate.h"
+
+namespace ash {
+
+class ASH_EXPORT DragHandle : public views::View,
+                              public views::ViewTargeterDelegate {
+ public:
+  explicit DragHandle(gfx::Size drag_handle_size,
+                      AshColorProvider::RippleAttributes ripple_attributes,
+                      int drag_handle_corner_radius);
+  DragHandle(const DragHandle&) = delete;
+  ~DragHandle() override;
+
+  DragHandle& operator=(const DragHandle&) = delete;
+
+  // views::ViewTargeterDelegate:
+  bool DoesIntersectRect(const views::View* target,
+                         const gfx::Rect& rect) const override;
+};
+
+}  // namespace ash
+
+#endif  // ASH_SHELF_DRAG_HANDLE_H_

ash/shelf/shelf_widget.cc

@@ -17,6 +17,7 @@
 #include "ash/public/cpp/window_properties.h"
 #include "ash/root_window_controller.h"
 #include "ash/session/session_controller_impl.h"
+#include "ash/shelf/drag_handle.h"
 #include "ash/shelf/home_button.h"
 #include "ash/shelf/hotseat_transition_animator.h"
 #include "ash/shelf/hotseat_widget.h"
@@ -165,7 +166,7 @@ class ShelfWidget::DelegateView : public views::WidgetDelegate,
 
   // A drag handle shown in tablet mode when we are not on the home screen.
   // Owned by the view hierarchy.
-  views::View* drag_handle_ = nullptr;
+  DragHandle* drag_handle_ = nullptr;
 
   // When true, the default focus of the shelf is the last focusable child.
   bool default_last_focusable_child_ = false;
@@ -197,26 +198,18 @@ ShelfWidget::DelegateView::DelegateView(ShelfWidget* shelf_widget)
   ShowAnimatingBackground(false);
   animating_background_.SetColor(ShelfConfig::Get()->GetMaximizedShelfColor());
 
-  std::unique_ptr<views::View> drag_handle_ptr =
-      std::make_unique<views::View>();
-  const int radius = kDragHandleCornerRadius;
   const AshColorProvider::RippleAttributes ripple_attributes =
       AshColorProvider::Get()->GetRippleAttributes(
           ShelfConfig::Get()->GetDefaultShelfColor());
-  drag_handle_ = AddChildView(std::move(drag_handle_ptr));
-  drag_handle_->SetPaintToLayer(ui::LAYER_SOLID_COLOR);
-  drag_handle_->layer()->SetColor(ripple_attributes.base_color);
-  // TODO(manucornet): Figure out why we need a manual opacity adjustment
-  // to make this color look the same as the status area highlight.
-  drag_handle_->layer()->SetOpacity(ripple_attributes.inkdrop_opacity + 0.075);
-  drag_handle_->layer()->SetRoundedCornerRadius(
-      {radius, radius, radius, radius});
-  drag_handle_->SetSize(kDragHandleSize);
+
+  drag_handle_ = AddChildView(std::make_unique<DragHandle>(
+      kDragHandleSize, ripple_attributes, kDragHandleCornerRadius));
 
   animating_drag_handle_.SetColor(ripple_attributes.base_color);
   animating_drag_handle_.SetOpacity(ripple_attributes.inkdrop_opacity + 0.075);
   animating_drag_handle_.SetRoundedCornerRadius(
-      {radius, radius, radius, radius});
+      {kDragHandleCornerRadius, kDragHandleCornerRadius,
+       kDragHandleCornerRadius, kDragHandleCornerRadius});
 }
 
 ShelfWidget::DelegateView::~DelegateView() = default;