content/browser/renderer_host/input/synthetic_gesture_controller.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/renderer_host/input/synthetic_gesture_controller.h"
   6
   7 #include "base/debug/trace_event.h"
   8 #include "content/browser/renderer_host/input/synthetic_gesture_target.h"
   9 #include "content/common/input/synthetic_smooth_scroll_gesture_params.h"
  10 #include "content/common/input_messages.h"
  11 #include "content/public/browser/render_widget_host.h"
  12
  13 namespace content {
  14
  15 SyntheticGestureController::SyntheticGestureController(
  16     scoped_ptr<SyntheticGestureTarget> gesture_target)
  17     : gesture_target_(gesture_target.Pass()) {}
  18
  19 SyntheticGestureController::~SyntheticGestureController() {}
  20
  21 void SyntheticGestureController::QueueSyntheticGesture(
  22     scoped_ptr<SyntheticGesture> synthetic_gesture) {
  23   DCHECK(synthetic_gesture);
  24
  25   pending_gesture_queue_.push_back(synthetic_gesture.release());
  26
  27   // Start forwarding input events if the queue was previously empty.
  28   if (pending_gesture_queue_.size() == 1)
  29     StartGesture(*pending_gesture_queue_.front());
  30 }
  31
  32 void SyntheticGestureController::Flush(base::TimeTicks timestamp) {
  33   if (pending_gesture_queue_.empty())
  34     return;
  35
  36   SyntheticGesture::Result result =
  37       pending_gesture_queue_.front()->ForwardInputEvents(timestamp,
  38                                                          gesture_target_.get());
  39
  40   if (result == SyntheticGesture::GESTURE_RUNNING) {
  41     gesture_target_->SetNeedsFlush();
  42     return;
  43   }
  44
  45   StopGesture(*pending_gesture_queue_.front(), result);
  46   pending_gesture_queue_.erase(pending_gesture_queue_.begin());
  47
  48   if (!pending_gesture_queue_.empty())
  49     StartGesture(*pending_gesture_queue_.front());
  50 }
  51
  52 void SyntheticGestureController::StartGesture(const SyntheticGesture& gesture) {
  53   TRACE_EVENT_ASYNC_BEGIN0("benchmark", "SyntheticGestureController::running",
  54                            &gesture);
  55   gesture_target_->SetNeedsFlush();
  56 }
  57
  58 void SyntheticGestureController::StopGesture(
  59     const SyntheticGesture& gesture, SyntheticGesture::Result result) {
  60   DCHECK_NE(result, SyntheticGesture::GESTURE_RUNNING);
  61   TRACE_EVENT_ASYNC_END0("benchmark", "SyntheticGestureController::running",
  62                          &gesture);
  63
  64   gesture_target_->OnSyntheticGestureCompleted(result);
  65 }
  66
  67 }  // namespace content