Unified Gesture Recognizer

ui/events/gestures/gesture_provider_aura.cc

+// Copyright 2014 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 "ui/events/gestures/gesture_provider_aura.h"
+
+#include "base/logging.h"
+#include "ui/events/event.h"
+#include "ui/events/gesture_detection/gesture_config_helper.h"
+#include "ui/events/gesture_detection/gesture_event_data.h"
+
+namespace ui {
+
+GestureProviderAura::GestureProviderAura(GestureProviderAuraClient* client)
+    : client_(client),
+      filtered_gesture_provider_(ui::DefaultGestureProviderConfig(), this) {
+  filtered_gesture_provider_.SetDoubleTapSupportForPlatformEnabled(false);
+}
+
+GestureProviderAura::~GestureProviderAura() {}
+
+bool GestureProviderAura::OnTouchEvent(const TouchEvent& event) {
+  last_touch_event_flags_ = event.flags();
+  bool pointer_id_is_active = false;
+  for (size_t i = 0; i < pointer_state_.GetPointerCount(); ++i) {
+    if (event.touch_id() != pointer_state_.GetPointerId(i))
+      continue;
+    pointer_id_is_active = true;
+    break;
+  }
+
+  if (event.type() == ET_TOUCH_PRESSED && pointer_id_is_active) {
+    // Ignore touch press events if we already believe the pointer is down.
+    return false;
+  } else if (event.type() != ET_TOUCH_PRESSED && !pointer_id_is_active) {
+    // We could have an active touch stream transfered to us, resulting in touch
+    // move or touch up events without associated touch down events. Ignore
+    // them.
+    return false;
+  }
+
+  pointer_state_.OnTouch(event);
+  bool result = filtered_gesture_provider_.OnTouchEvent(pointer_state_);
+  pointer_state_.CleanupRemovedTouchPoints(event);
+  return result;
+}
+
+void GestureProviderAura::OnTouchEventAck(bool event_consumed) {
+  filtered_gesture_provider_.OnTouchEventAck(event_consumed);
+}
+
+void GestureProviderAura::OnGestureEvent(
+    const GestureEventData& gesture) {
+  scoped_ptr<ui::GestureEvent> event(

[sadrul, 2014/05/07 13:42:17]

Why scoped_ptr<>? Can't we just create this on the stack and pass a
pointer/const-ref to the client?

[tdresser, 2014/05/07 14:04:17]

Done.

+      new ui::GestureEvent(gesture.type,
+                           gesture.x,
+                           gesture.y,
+                           last_touch_event_flags_,
+                           gesture.time - base::TimeTicks(),
+                           gesture.details,
+                           // ui::GestureEvent stores a bitfield indicating the
+                           // ids of active touch points. This is currently only
+                           // used when one finger is down, and will eventually
+                           // be cleaned up. See crbug.com/366707.
+                           1 << gesture.motion_event_id));
+  client_->OnGestureEvent(event.Pass());
+}
+
+}  // namespace content