touch: Gesture manager receives the touch-sequence status.

OnTouchEvent now returns the status of the touch sequence, instead of a simple
bool. The gesture manager can presumably make a better decision if this
information is available to it. For more details: http://codereview.chromium.org/6347002/

BUG=none
TEST=ViewTest.TouchEvent

Review URL: http://codereview.chromium.org/6253005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71824 0039d316-1c4b-4281-b951-d872f2087c98

views/touchui/gesture_manager.cc

@@ -22,9 +22,9 @@ GestureManager* GestureManager::GetInstance() {
 
 bool GestureManager::ProcessTouchEventForGesture(const TouchEvent& event,
                                                  View* source,
-                                                 bool previouslyHandled) {
-  if (previouslyHandled)
-    return false;
+                                                 View::TouchStatus status) {
+  if (status != View::TOUCH_STATUS_UNKNOWN)
+    return false;  // The event was consumed by a touch sequence.
 
   // TODO(rjkroege): A realistic version of the GestureManager will
   // appear in a subsequent CL. This interim version permits verifying that the

views/touchui/gesture_manager.h

@@ -7,12 +7,11 @@
 #pragma once
 
 #include "base/singleton.h"
+#include "views/view.h"
 
 namespace views {
-class View;
 class TouchEvent;
 
-
 // A GestureManager singleton detects gestures occurring in the
 // incoming feed of touch events across all of the RootViews in
 // the system. In response to a given touch event, the GestureManager
@@ -25,17 +24,16 @@ class GestureManager {
 
   static GestureManager* GetInstance();
 
-  // TODO(sad): Use TouchStatus instead of bool for previouslyHandled.
   // Invoked for each touch event that could contribute to the current gesture.
   // Takes the event and the View that originated it and which will also
-  // be the target of any generated synthetic event. Finally, handled
-  // specifies if the event was actually handled explicitly by a view so that
+  // be the target of any generated synthetic event. Finally, status
+  // specifies if a touch sequence is in progress or not, so that the
   // GestureManager state can correctly reflect events that are handled
   // already.
   // Returns true if the event resulted in firing a synthetic event.
   virtual bool ProcessTouchEventForGesture(const TouchEvent& event,
                                            View* source,
-                                           bool previouslyHandled);
+                                           View::TouchStatus status);
 
   // TODO(rjkroege): Write the remainder of this class.
   // It will appear in a subsequent CL.

views/view_unittest.cc

@@ -178,6 +178,7 @@ class TestView : public View {
   // TouchEvent
   int last_touch_event_type_;
   bool last_touch_event_was_handled_;
+  bool in_touch_sequence_;
 #endif
 
   // Painting
@@ -201,7 +202,7 @@ class MockGestureManager : public GestureManager {
 
   bool ProcessTouchEventForGesture(const TouchEvent& event,
                                    View* source,
-                                   bool previouslyHandled);
+                                   View::TouchStatus status);
   MockGestureManager();
 
   bool previously_handled_flag_;
@@ -414,14 +415,14 @@ TEST_F(ViewTest, MouseEvent) {
 bool MockGestureManager::ProcessTouchEventForGesture(
     const TouchEvent& event,
     View* source,
-    bool previouslyHandled) {
-  if (previouslyHandled) {
+    View::TouchStatus status) {
+  if (status != View::TOUCH_STATUS_UNKNOWN) {
     dispatched_synthetic_event_ = false;
     return false;
   }
   last_touch_event_ =  event.GetType();
   last_view_ = source;
-  previously_handled_flag_ = previouslyHandled;
+  previously_handled_flag_ = status != View::TOUCH_STATUS_UNKNOWN;
   dispatched_synthetic_event_ = true;
   return true;
 }
@@ -432,6 +433,18 @@ MockGestureManager::MockGestureManager() {
 View::TouchStatus TestView::OnTouchEvent(const TouchEvent& event) {
   last_touch_event_type_ = event.GetType();
   location_.SetPoint(event.x(), event.y());
+  if (!in_touch_sequence_) {
+    if (event.GetType() == Event::ET_TOUCH_PRESSED) {
+      in_touch_sequence_ = true;
+      return TOUCH_STATUS_START;
+    }
+  } else {
+    if (event.GetType() == Event::ET_TOUCH_RELEASED) {
+      in_touch_sequence_ = false;
+      return TOUCH_STATUS_END;
+    }
+    return TOUCH_STATUS_CONTINUE;
+  }
   return last_touch_event_was_handled_ ? TOUCH_STATUS_CONTINUE :
                                          TOUCH_STATUS_UNKNOWN;
 }

views/widget/root_view.cc

@@ -315,13 +315,12 @@ View::TouchStatus RootView::OnTouchEvent(const TouchEvent& e) {
   if (touch_pressed_handler_) {
     TouchEvent touch_event(e, this, touch_pressed_handler_);
     status = touch_pressed_handler_->ProcessTouchEvent(touch_event);
-    gesture_manager_->ProcessTouchEventForGesture(e, this, true);
+    gesture_manager_->ProcessTouchEventForGesture(e, this, status);
     if (status == TOUCH_STATUS_END)
       touch_pressed_handler_ = NULL;
     return status;
   }
 
-  bool handled = false;
   // Walk up the tree until we find a view that wants the touch event.
   for (touch_pressed_handler_ = GetViewForPoint(e.location());
        touch_pressed_handler_ && (touch_pressed_handler_ != this);
@@ -329,7 +328,6 @@ View::TouchStatus RootView::OnTouchEvent(const TouchEvent& e) {
     if (!touch_pressed_handler_->IsEnabled()) {
       // Disabled views eat events but are treated as not handled by the
       // the GestureManager.
-      handled = false;
       status = TOUCH_STATUS_UNKNOWN;
       break;
     }
@@ -343,8 +341,6 @@ View::TouchStatus RootView::OnTouchEvent(const TouchEvent& e) {
     if (status != TOUCH_STATUS_START)
       touch_pressed_handler_ = NULL;
 
-    handled = status != TOUCH_STATUS_UNKNOWN;
-
     // The view could have removed itself from the tree when handling
     // OnTouchEvent(). So handle as per OnMousePressed. NB: we
     // assume that the RootView itself cannot be so removed.
@@ -357,8 +353,8 @@ View::TouchStatus RootView::OnTouchEvent(const TouchEvent& e) {
     // If the view handled the event, leave touch_pressed_handler_ set and
     // return true, which will cause subsequent drag/release events to get
     // forwarded to that view.
-    if (handled) {
-      gesture_manager_->ProcessTouchEventForGesture(e, this, handled);
+    if (status != TOUCH_STATUS_UNKNOWN) {
+      gesture_manager_->ProcessTouchEventForGesture(e, this, status);
       return status;
     }
   }
@@ -367,7 +363,7 @@ View::TouchStatus RootView::OnTouchEvent(const TouchEvent& e) {
   touch_pressed_handler_ = NULL;
 
   // Give the touch event to the gesture manager.
-  gesture_manager_->ProcessTouchEventForGesture(e, this, handled);
+  gesture_manager_->ProcessTouchEventForGesture(e, this, status);
   return status;
 }
 #endif