cros: Add touch selection to window cycle list (alt+tab).

As an ongoing effort to make the window cycle list more interactive,
this CL makes it so users can select and confirm a selection by tapping
a preview item in the window cycle list.

Test: InteractiveWindowCycleControllerTest.TapSelect
Bug: 1067327
Change-Id: Ice8cbcfe0e1886a15169f50eaf3172e96acb03e7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2367497
Commit-Queue: Jeremy Chinsen <chinsenj@chromium.org>
Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#801625}

ash/wm/window_cycle_controller.cc

@@ -129,7 +129,7 @@ void WindowCycleController::StepToWindow(aura::Window* window) {
   window_cycle_list_->StepToWindow(window);
 }
 
-bool WindowCycleController::IsEventInCycleView(ui::MouseEvent* event) {
+bool WindowCycleController::IsEventInCycleView(ui::LocatedEvent* event) {
   return window_cycle_list_ && window_cycle_list_->IsEventInCycleView(event);
 }
 

ash/wm/window_cycle_controller.h

@@ -17,7 +17,7 @@ class Window;
 }
 
 namespace ui {
-class MouseEvent;
+class LocatedEvent;
 }
 
 namespace ash {
@@ -64,7 +64,7 @@ class ASH_EXPORT WindowCycleController {
   void StepToWindow(aura::Window* window);
 
   // Checks whether |event| occurs within the cycle view.
-  bool IsEventInCycleView(ui::MouseEvent* event);
+  bool IsEventInCycleView(ui::LocatedEvent* event);
 
   // Returns the WindowCycleList.
   const WindowCycleList* window_cycle_list() const {

ash/wm/window_cycle_controller_unittest.cc

@@ -973,6 +973,30 @@ TEST_F(InteractiveWindowCycleControllerTest, KeysConfirmSelection) {
   EXPECT_TRUE(wm::IsActiveWindow(w1.get()));
 }
 
+// When a user taps on an item, it should cycle to it, complete cycling and
+// activate the tapped item.
+TEST_F(InteractiveWindowCycleControllerTest, TapSelect) {
+  std::unique_ptr<Window> w0 = CreateTestWindow();
+  std::unique_ptr<Window> w1 = CreateTestWindow();
+  std::unique_ptr<Window> w2 = CreateTestWindow();
+  ui::test::EventGenerator* generator = GetEventGenerator();
+  WindowCycleController* controller = Shell::Get()->window_cycle_controller();
+
+  // Start cycle and tap third item.
+  // Starting order of windows in cycle list is [2,1,0].
+  controller->StartCycling();
+  generator->GestureTapAt(
+      GetWindowCycleItemViews()[2]->GetBoundsInScreen().CenterPoint());
+  EXPECT_TRUE(wm::IsActiveWindow(w0.get()));
+
+  // Start cycle and tap second item.
+  // Starting order of windows in cycle list is [0,2,1].
+  controller->StartCycling();
+  generator->GestureTapAt(
+      GetWindowCycleItemViews()[1]->GetBoundsInScreen().CenterPoint());
+  EXPECT_TRUE(wm::IsActiveWindow(w2.get()));
+}
+
 // Tests that frame throttling starts and ends accordingly when window cycling
 // starts and ends.
 TEST_F(WindowCycleControllerTest, FrameThrottling) {

ash/wm/window_cycle_event_filter.cc

@@ -117,6 +117,25 @@ void WindowCycleEventFilter::OnMouseEvent(ui::MouseEvent* event) {
   }
 }
 
+void WindowCycleEventFilter::OnGestureEvent(ui::GestureEvent* event) {
+  if (features::IsInteractiveWindowCycleListEnabled() &&
+      Shell::Get()->window_cycle_controller()->IsEventInCycleView(event)) {
+    return;
+  }
+
+  // Prevent any form of tap from doing anything while the Alt+Tab UI is active.
+  if (event->type() == ui::ET_GESTURE_TAP ||
+      event->type() == ui::ET_GESTURE_DOUBLE_TAP ||
+      event->type() == ui::ET_GESTURE_TAP_CANCEL ||
+      event->type() == ui::ET_GESTURE_TAP_DOWN ||
+      event->type() == ui::ET_GESTURE_TAP_UNCONFIRMED ||
+      event->type() == ui::ET_GESTURE_TWO_FINGER_TAP ||
+      event->type() == ui::ET_GESTURE_LONG_PRESS ||
+      event->type() == ui::ET_GESTURE_LONG_TAP) {
+    event->StopPropagation();
+  }
+}
+
 WindowCycleEventFilter::AltReleaseHandler::AltReleaseHandler() = default;
 
 WindowCycleEventFilter::AltReleaseHandler::~AltReleaseHandler() = default;

ash/wm/window_cycle_event_filter.h

@@ -24,6 +24,7 @@ class ASH_EXPORT WindowCycleEventFilter : public ui::EventHandler {
   // Overridden from ui::EventHandler:
   void OnKeyEvent(ui::KeyEvent* event) override;
   void OnMouseEvent(ui::MouseEvent* event) override;
+  void OnGestureEvent(ui::GestureEvent* event) override;
 
  private:
   class AltReleaseHandler : public ui::EventHandler {

ash/wm/window_cycle_list.cc

@@ -11,6 +11,7 @@
 #include "ash/accessibility/accessibility_controller_impl.h"
 #include "ash/app_list/app_list_controller_impl.h"
 #include "ash/frame_throttler/frame_throttling_controller.h"
+#include "ash/public/cpp/ash_features.h"
 #include "ash/public/cpp/metrics_util.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/public/cpp/window_properties.h"
@@ -38,6 +39,7 @@
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
 #include "ui/wm/core/window_animations.h"
+#include "ui/wm/core/coordinate_conversion.h"
 
 namespace ash {
 
@@ -147,6 +149,23 @@ class WindowCycleItemView : public WindowMiniView {
     return true;
   }
 
+  void OnGestureEvent(ui::GestureEvent* event) override {
+    switch (event->type()) {
+      case ui::ET_GESTURE_TAP:
+      case ui::ET_GESTURE_LONG_PRESS:
+      case ui::ET_GESTURE_LONG_TAP:
+      case ui::ET_GESTURE_TWO_FINGER_TAP: {
+        WindowCycleController* controller =
+            Shell::Get()->window_cycle_controller();
+        controller->StepToWindow(source_window());
+        controller->CompleteCycling();
+        break;
+      }
+      default:
+        break;
+    }
+  }
+
  private:
   // WindowMiniView:
   gfx::Size GetPreviewViewSize() const override {
@@ -545,9 +564,12 @@ void WindowCycleList::StepToWindow(aura::Window* window) {
   Step(target_index - current_index_);
 }
 
-bool WindowCycleList::IsEventInCycleView(ui::MouseEvent* event) {
-  return cycle_view_->GetBoundsInScreen().Contains(
-      display::Screen::GetScreen()->GetCursorScreenPoint());
+bool WindowCycleList::IsEventInCycleView(ui::LocatedEvent* event) {
+  aura::Window* target = static_cast<aura::Window*>(event->target());
+  aura::Window* event_root = target->GetRootWindow();
+  gfx::Point event_screen_point = event->root_location();
+  wm::ConvertPointToScreen(event_root, &event_screen_point);
+  return cycle_view_->GetBoundsInScreen().Contains(event_screen_point);
 }
 
 // static

ash/wm/window_cycle_list.h

@@ -49,7 +49,7 @@ class ASH_EXPORT WindowCycleList : public aura::WindowObserver,
   void StepToWindow(aura::Window* window);
 
   // Checks whether |event| occurs within the cycle view.
-  bool IsEventInCycleView(ui::MouseEvent* event);
+  bool IsEventInCycleView(ui::LocatedEvent* event);
 
   void set_user_did_accept(bool user_did_accept) {
     user_did_accept_ = user_did_accept;