ash: Remove some inconsistency from two-finger window moving.

Allow two-finger window moving only if both fingers are on the same edge of the window.

BUG=151153

Review URL: https://codereview.chromium.org/11269031

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@164094 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 109 insertions, 10 deletions

diff --git a/ash/wm/gestures/two_finger_drag_handler.cc b/ash/wm/gestures/two_finger_drag_handler.cc
index b60dee7..7ed214a 100644
--- a/ash/wm/gestures/two_finger_drag_handler.cc
+++ b/ash/wm/gestures/two_finger_drag_handler.cc
@@ -9,16 +9,71 @@
 #include "ash/wm/workspace/snap_sizer.h"
 #include "ui/aura/client/window_types.h"
 #include "ui/aura/window.h"
+#include "ui/aura/window_delegate.h"
 #include "ui/base/events/event.h"
 #include "ui/base/events/event_constants.h"
 #include "ui/base/hit_test.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 
+namespace {
+
+bool IsTopEdge(int component) {
+  return component == HTTOPLEFT ||
+         component == HTTOP ||
+         component == HTTOPRIGHT;
+}
+
+bool IsBottomEdge(int component) {
+  return component == HTBOTTOMLEFT ||
+         component == HTBOTTOM ||
+         component == HTBOTTOMRIGHT;
+}
+
+bool IsRightEdge(int component) {
+  return component == HTTOPRIGHT ||
+         component == HTRIGHT ||
+         component == HTBOTTOMRIGHT;
+}
+
+bool IsLeftEdge(int component) {
+  return component == HTTOPLEFT ||
+         component == HTLEFT ||
+         component == HTBOTTOMLEFT;
+}
+
+bool IsSomeEdge(int component) {
+  switch (component) {
+    case HTTOPLEFT:
+    case HTTOP:
+    case HTTOPRIGHT:
+    case HTRIGHT:
+    case HTBOTTOMRIGHT:
+    case HTBOTTOM:
+    case HTBOTTOMLEFT:
+    case HTLEFT:
+      return true;
+  }
+  return false;
+}
+
+// Returns whether a window-move should be allowed depending on the hit-test
+// results of the two fingers.
+bool WindowComponentsAllowMoving(int component1, int component2) {
+  return ((IsTopEdge(component1) && IsTopEdge(component2)) ||
+          (IsBottomEdge(component1) && IsBottomEdge(component2)) ||
+          (IsLeftEdge(component1) && IsLeftEdge(component2)) ||
+          (IsRightEdge(component1) && IsRightEdge(component2)) ||
+          (!IsSomeEdge(component1) && !IsSomeEdge(component2)));
+}
+
+}  // namespace
+
 namespace ash {
 namespace internal {
 
-TwoFingerDragHandler::TwoFingerDragHandler() {
+TwoFingerDragHandler::TwoFingerDragHandler()
+    : first_finger_hittest_(HTNOWHERE) {
 }
 
 TwoFingerDragHandler::~TwoFingerDragHandler() {
@@ -27,20 +82,34 @@ TwoFingerDragHandler::~TwoFingerDragHandler() {
 bool TwoFingerDragHandler::ProcessGestureEvent(aura::Window* target,
                                                const ui::GestureEvent& event) {
   if (event.type() == ui::ET_GESTURE_BEGIN &&
+      event.details().touch_points() == 1) {
+    first_finger_hittest_ =
+        target->delegate()->GetNonClientComponent(event.location());
+    return false;
+  }
+
+  if (event.type() == ui::ET_GESTURE_BEGIN &&
       event.details().touch_points() == 2) {
     if (wm::IsWindowNormal(target) &&
       target->type() == aura::client::WINDOW_TYPE_NORMAL) {
-      target->AddObserver(this);
-      window_resizer_ = CreateWindowResizer(target,
-          event.details().bounding_box().CenterPoint(), HTCAPTION);
-      return true;
+      if (WindowComponentsAllowMoving(first_finger_hittest_,
+          target->delegate()->GetNonClientComponent(event.location()))) {
+        target->AddObserver(this);
+        window_resizer_ = CreateWindowResizer(target,
+            event.details().bounding_box().CenterPoint(), HTCAPTION);
+        return true;
+      }
     }
 
     return false;
   }
 
-  if (!window_resizer_.get())
-    return false;
+  if (!window_resizer_.get()) {
+    // Consume all two-finger gestures on a normal window.
+    return event.details().touch_points() == 2 &&
+           target->type() == aura::client::WINDOW_TYPE_NORMAL &&
+           wm::IsWindowNormal(target);
+  }
 
   switch (event.type()) {
     case ui::ET_GESTURE_BEGIN:
diff --git a/ash/wm/gestures/two_finger_drag_handler.h b/ash/wm/gestures/two_finger_drag_handler.h
index 3e91a16..06cb86d 100644
--- a/ash/wm/gestures/two_finger_drag_handler.h
+++ b/ash/wm/gestures/two_finger_drag_handler.h
@@ -42,6 +42,8 @@ class TwoFingerDragHandler : public aura::WindowObserver {
                                          bool visible) OVERRIDE;
   virtual void OnWindowDestroying(aura::Window* window) OVERRIDE;
 
+  int first_finger_hittest_;
+
   scoped_ptr<WindowResizer> window_resizer_;
 
   DISALLOW_COPY_AND_ASSIGN(TwoFingerDragHandler);
diff --git a/ash/wm/system_gesture_event_filter_unittest.cc b/ash/wm/system_gesture_event_filter_unittest.cc
index 7c795b2..9711b12 100644
--- a/ash/wm/system_gesture_event_filter_unittest.cc
+++ b/ash/wm/system_gesture_event_filter_unittest.cc
@@ -25,6 +25,7 @@
 #include "ui/aura/test/event_generator.h"
 #include "ui/aura/test/test_windows.h"
 #include "ui/base/events/event.h"
+#include "ui/base/hit_test.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/gfx/screen.h"
 #include "ui/views/widget/widget_delegate.h"
@@ -641,5 +642,32 @@ TEST_F(SystemGestureEventFilterTest, TwoFingerDrag) {
   EXPECT_EQ(current_bounds.ToString(), right_tile_bounds.ToString());
 }
 
+TEST_F(SystemGestureEventFilterTest, TwoFingerDragEdge) {
+  gfx::Rect bounds(0, 0, 100, 100);
+  aura::RootWindow* root_window = Shell::GetPrimaryRootWindow();
+  views::Widget* toplevel = views::Widget::CreateWindowWithBounds(
+      new ResizableWidgetDelegate, bounds);
+  toplevel->Show();
+
+  const int kSteps = 15;
+  const int kTouchPoints = 2;
+  gfx::Point points[kTouchPoints] = {
+    gfx::Point(30, 20),  // Caption
+    gfx::Point(0, 40),   // Left edge
+  };
+
+  EXPECT_EQ(HTLEFT, toplevel->GetNativeWindow()->delegate()->
+        GetNonClientComponent(points[1]));
+
+  aura::test::EventGenerator generator(root_window,
+                                       toplevel->GetNativeWindow());
+
+  bounds = toplevel->GetNativeWindow()->bounds();
+  // Swipe down. Nothing should happen.
+  generator.GestureMultiFingerScroll(kTouchPoints, points, 15, kSteps, 0, 150);
+  EXPECT_EQ(bounds.ToString(),
+            toplevel->GetNativeWindow()->bounds().ToString());
+}
+
 }  // namespace test
 }  // namespace ash
diff --git a/ui/base/hit_test.h b/ui/base/hit_test.h
index 9fb46a4..a91ce89 100644
--- a/ui/base/hit_test.h
+++ b/ui/base/hit_test.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef VIEWS_WINDOW_HIT_TEST_H_
-#define VIEWS_WINDOW_HIT_TEST_H_
+#ifndef UI_BASE_HIT_TEST_H_
+#define UI_BASE_HIT_TEST_H_
 
 #if !defined(OS_WIN)
 
@@ -42,4 +42,4 @@ enum HitTestCompat {
 
 #endif  // !defined(OS_WIN)
 
-#endif  // VIEWS_WINDOW_HIT_TEST_H_
+#endif  // UI_BASE_HIT_TEST_H_