Initial views touchui GestureRecognizer support

views/widget/root_view.cc

 // Copyright (c) 2011 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 "views/widget/root_view.h"
 
 #include <algorithm>
 
+#include "base/command_line.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "chrome/common/chrome_switches.h"

[Ian Vollick, 2011/11/08 20:07:54]

views/ is not allowed to depend on chrome/, so you can't use chrome_switches.
See views/examples/examples_main.cc:181. You might want to declare
kEnableGesture in the switches namespace here in this file (or possibly in an
unnamed namespace).

[Gajen, 2011/11/10 15:52:55]

Deprecated, as no longer required in new Design.

 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/dragdrop/drag_drop_types.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/compositor/layer.h"
 #include "views/focus/view_storage.h"
 #include "views/layout/fill_layout.h"
 #include "views/touchui/gesture_manager.h"
 #include "views/widget/widget.h"
 
@@ skipping 10 matching lines @@
 
 RootView::RootView(Widget* widget)
     : widget_(widget),
       mouse_pressed_handler_(NULL),
       mouse_move_handler_(NULL),
       last_click_handler_(NULL),
       explicit_mouse_handler_(false),
       last_mouse_event_flags_(0),
       last_mouse_event_x_(-1),
       last_mouse_event_y_(-1),
-      gesture_manager_(GestureManager::GetInstance()),
+      gesture_manager_(NULL),
       touch_pressed_handler_(NULL),
+      gesture_handling_view_(NULL),
       ALLOW_THIS_IN_INITIALIZER_LIST(focus_search_(this, false, false)),
       focus_traversable_parent_(NULL),
       focus_traversable_parent_view_(NULL) {
+  // TODO(Gajen): Refactor gesture recognizer integration with new approach
+  // proposed in http://codereview.chromium.org/8364039/.
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableGesture))
+    gesture_manager_ = GestureRecognizer::GetInstance();
+  else
+    gesture_manager_ = GestureManager::GetInstance();
 }
 
 RootView::~RootView() {
   // If we have children remove them explicitly so to make sure a remove
   // notification is sent for each one of them.
   if (has_children())
     RemoveAllChildViews(true);
 }
 
 // Tree operations -------------------------------------------------------------
@@ skipping 337 matching lines @@
 void RootView::SetMouseHandler(View *new_mh) {
   // If we're clearing the mouse handler, clear explicit_mouse_handler_ as well.
   explicit_mouse_handler_ = (new_mh != NULL);
   mouse_pressed_handler_ = new_mh;
 }
 
 void RootView::GetAccessibleState(ui::AccessibleViewState* state) {
   state->role = ui::AccessibilityTypes::ROLE_APPLICATION;
 }
 
+bool RootView::ForwardGestureEvents(GestureRecognizer::Gestures* gestures) {
+  scoped_ptr<GestureRecognizer::Gestures> events;
+  events.reset(gestures);
+  bool return_value = false;
+  for (unsigned int i = 0; i < events->size(); i++) {
+    GestureEvent* event = gestures->at(i).GetGestureEvent();
+    GestureEvent e(*event, this);
+
+    ui::GestureStatus status = ui::GESTURE_STATUS_UNKNOWN;
+
+    // Walk up the tree until we find a view that wants the gesture event.
+    for (gesture_handling_view_ = GetEventHandlerForPoint(e.location());
+         gesture_handling_view_ && (gesture_handling_view_ != this);
+         gesture_handling_view_ = gesture_handling_view_->parent()) {
+      if (!gesture_handling_view_->IsEnabled()) {
+        // Disabled views eat events but are treated as not handled by the
+        // the GestureManager.
+        status = ui::GESTURE_STATUS_UNKNOWN;
+        break;
+      }
+
+      // See if this view wants to handle the Gesture.
+      GestureEvent gesture_event(e, this, gesture_handling_view_);
+      status = gesture_handling_view_->ProcessGestureEvent(gesture_event);
+
+      // The view could have removed itself from the tree when handling
+      // OnGestureEvent(). So handle as per OnMousePressed. NB: we
+      // assume that the RootView itself cannot be so removed.
+      if (!gesture_handling_view_)
+        break;
+
+      // The gesture event wasn't processed. Go up the view hierarchy and
+      // dispatch the gesture event.
+      if (status == ui::GESTURE_STATUS_UNKNOWN) {
+        continue;
+      } else if (status == ui::GESTURE_STATUS_CONSUMED) {
+        return_value = true;
+      } else {
+        return_value = false;
+      }
+    }
+    if (!return_value) return false;
+  }
+  return return_value;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // RootView, protected:
 
 void RootView::ViewHierarchyChanged(bool is_add, View* parent, View* child) {
   widget_->ViewHierarchyChanged(is_add, parent, child);
 
   if (!is_add) {
     if (!explicit_mouse_handler_ && mouse_pressed_handler_ == child)
       mouse_pressed_handler_ = NULL;
     if (mouse_move_handler_ == child)
       mouse_move_handler_ = NULL;
     if (touch_pressed_handler_ == child)
       touch_pressed_handler_ = NULL;
+    if (gesture_handling_view_ == child)
+      gesture_handling_view_ = NULL;
   }
 }
 
 void RootView::OnPaint(gfx::Canvas* canvas) {
   if (!layer() || !layer()->fills_bounds_opaquely())
     canvas->GetSkCanvas()->drawColor(SK_ColorBLACK, SkXfermode::kClear_Mode);
 
   // TODO (pkotwicz): Remove this once we switch over to Aura desktop.
   // This is needed so that we can set the background behind the RWHV when the
   // RWHV is not visible. Not needed once there is a view between the RootView
@@ skipping 21 matching lines @@
 }
 
 void RootView::SetMouseLocationAndFlags(const MouseEvent& event) {
   last_mouse_event_flags_ = event.flags();
   last_mouse_event_x_ = event.x();
   last_mouse_event_y_ = event.y();
 }
 
 }  // namespace internal
 }  // namespace views