[Android] Out with the Android GR, in with the new unified C++ GR

content/browser/renderer_host/input/content_gesture_provider.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 "content/browser/renderer_host/input/content_gesture_provider.h"
+
+#include "base/auto_reset.h"
+#include "base/logging.h"
+#include "ui/events/gesture_detection/gesture_config_helper.h"
+#include "ui/events/gesture_detection/gesture_event_params.h"
+#include "ui/events/gesture_detection/motion_event.h"
+
+using blink::WebGestureEvent;
+using blink::WebInputEvent;
+
+namespace content {
+namespace {
+
+WebGestureEvent CreateGesture(const ui::GestureEventParams& params,

[tdresser, 2014/02/27 15:28:30]

This seems to be the only method which should be Android specific. Can we factor
this out into a separate class and rename things appropriately?

[jdduke (slow), 2014/02/27 17:40:29]

Hmm, I guess I fail to see how this is Android specific. This class could easily
be used by Mac (or Aura, honestly, but the equivalent in Aura needs to happen
higher in the stack apparently).

There will likely be an AuraGestureProvider or UIGestureProvider somewhere
outside of content/, but I see no reason to let that's existence affect how we
name this class. Does that make sense?

+                              float scale) {
+  WebGestureEvent gesture;
+  gesture.x = params.x * scale;
+  gesture.y = params.y * scale;
+  gesture.timeStampSeconds = (params.time - base::TimeTicks()).InSecondsF();
+  gesture.sourceDevice = WebGestureEvent::Touchscreen;
+
+  switch (params.type) {
+    case ui::GESTURE_SHOW_PRESS:
+      gesture.type = WebInputEvent::GestureShowPress;
+      gesture.data.showPress.width = params.data.show_press.width * scale;
+      gesture.data.showPress.width = params.data.show_press.width * scale;
+      break;
+    case ui::GESTURE_DOUBLE_TAP:
+      gesture.type = WebInputEvent::GestureDoubleTap;
+      break;
+    case ui::GESTURE_SINGLE_TAP_CONFIRMED:
+      gesture.type = WebInputEvent::GestureTap;
+      gesture.data.tap.tapCount = params.data.tap.tap_count;
+      gesture.data.tap.width = params.data.tap.width * scale;
+      gesture.data.tap.height = params.data.tap.height * scale;
+      break;
+    case ui::GESTURE_SINGLE_TAP_UNCONFIRMED:
+      gesture.type = WebInputEvent::GestureTapUnconfirmed;
+      gesture.data.tap.tapCount = params.data.tap.tap_count;
+      gesture.data.tap.width = params.data.tap.width * scale;
+      gesture.data.tap.height = params.data.tap.height * scale;
+      break;
+    case ui::GESTURE_LONG_PRESS:
+      gesture.type = WebInputEvent::GestureLongPress;
+      gesture.data.longPress.width = params.data.long_press.width * scale;
+      gesture.data.longPress.height = params.data.long_press.height * scale;
+      break;
+    case ui::GESTURE_LONG_TAP:
+      gesture.type = WebInputEvent::GestureLongTap;
+      gesture.data.longPress.width = params.data.long_press.width * scale;
+      gesture.data.longPress.height = params.data.long_press.height * scale;
+      break;
+    case ui::GESTURE_SCROLL_BEGIN:
+      gesture.type = WebInputEvent::GestureScrollBegin;
+      gesture.data.scrollBegin.deltaXHint =
+          params.data.scroll_begin.delta_x_hint * scale;
+      gesture.data.scrollBegin.deltaYHint =
+          params.data.scroll_begin.delta_y_hint * scale;
+      break;
+    case ui::GESTURE_SCROLL_UPDATE:
+      gesture.type = WebInputEvent::GestureScrollUpdate;
+      gesture.data.scrollUpdate.deltaX =
+          params.data.scroll_update.delta_x * scale;
+      gesture.data.scrollUpdate.deltaY =
+          params.data.scroll_update.delta_y * scale;
+      gesture.data.scrollUpdate.velocityX =
+          params.data.scroll_update.velocity_x * scale;
+      gesture.data.scrollUpdate.velocityY =
+          params.data.scroll_update.velocity_y * scale;
+      break;
+    case ui::GESTURE_SCROLL_END:
+      gesture.type = WebInputEvent::GestureScrollEnd;
+      break;
+    case ui::GESTURE_FLING_START:
+      gesture.type = WebInputEvent::GestureFlingStart;
+      gesture.data.flingStart.velocityX =
+          params.data.fling_start.velocity_x * scale;
+      gesture.data.flingStart.velocityY =
+          params.data.fling_start.velocity_y * scale;
+      break;
+    case ui::GESTURE_FLING_CANCEL:
+      gesture.type = WebInputEvent::GestureFlingCancel;
+      break;
+    case ui::GESTURE_PINCH_BEGIN:
+      gesture.type = WebInputEvent::GesturePinchBegin;
+      break;
+    case ui::GESTURE_PINCH_UPDATE:
+      gesture.type = WebInputEvent::GesturePinchUpdate;
+      gesture.data.pinchUpdate.scale = params.data.pinch_update.scale;
+      break;
+    case ui::GESTURE_PINCH_END:
+      gesture.type = WebInputEvent::GesturePinchEnd;
+      break;
+    case ui::GESTURE_TAP_CANCEL:
+      gesture.type = WebInputEvent::GestureTapCancel;
+      break;
+    case ui::GESTURE_TAP_DOWN:
+      gesture.type = WebInputEvent::GestureTapDown;
+      gesture.data.tapDown.width = params.data.tap_down.width * scale;
+      gesture.data.tapDown.height = params.data.tap_down.height * scale;
+      break;
+  }
+
+  return gesture;
+}
+
+}  // namespace
+
+ContentGestureProvider::ContentGestureProvider(
+    ContentGestureProviderClient* client,
+    float touch_to_gesture_scale)
+    : client_(client),
+      touch_to_gesture_scale_(touch_to_gesture_scale),
+      gesture_provider_(ui::DefaultGestureProviderConfig(), this),
+      gesture_filter_(this),
+      handling_event_(false) {}
+
+bool ContentGestureProvider::OnTouchEvent(const ui::MotionEvent& event) {
+  DCHECK(!handling_event_);
+  base::AutoReset<bool> handling_event(&handling_event_, true);
+
+  pending_gesture_packet_ = GestureEventPacket::FromTouch(event);
+
+  if (!gesture_provider_.OnTouchEvent(event))
+    return false;
+
+  TouchDispositionGestureFilter::PacketResult result =
+      gesture_filter_.OnGestureEventPacket(pending_gesture_packet_);
+  if (result != TouchDispositionGestureFilter::SUCCESS) {
+    NOTREACHED() << "Invalid touch gesture sequence detected.";
+    return false;
+  }
+
+  return true;
+}
+
+void ContentGestureProvider::OnTouchEventAck(InputEventAckState ack_state) {
+  gesture_filter_.OnTouchEventAck(ack_state);
+}
+
+void ContentGestureProvider::ResetGestureDetectors() {
+  gesture_provider_.ResetGestureDetectors();
+}
+
+void ContentGestureProvider::CancelActiveTouchSequence() {
+  gesture_provider_.CancelActiveTouchSequence();
+}
+
+void ContentGestureProvider::UpdateMultiTouchSupport(
+    bool support_multi_touch_zoom) {
+  gesture_provider_.UpdateMultiTouchSupport(support_multi_touch_zoom);
+}
+
+void ContentGestureProvider::UpdateDoubleTapSupportForPlatform(
+    bool support_double_tap) {
+  gesture_provider_.UpdateDoubleTapSupportForPlatform(support_double_tap);
+}
+
+void ContentGestureProvider::UpdateDoubleTapSupportForPage(
+    bool support_double_tap) {
+  gesture_provider_.UpdateDoubleTapSupportForPage(support_double_tap);
+}
+
+void ContentGestureProvider::OnGestureEvent(
+    const ui::GestureEventParams& params) {
+  WebGestureEvent gesture(CreateGesture(params, touch_to_gesture_scale_));
+  if (handling_event_) {
+    pending_gesture_packet_.Push(gesture);
+    return;
+  }
+
+  gesture_filter_.OnGestureEventPacket(
+      GestureEventPacket::FromTouchTimeout(gesture));
+}
+
+void ContentGestureProvider::ForwardGestureEvent(
+    const blink::WebGestureEvent& event) {
+  client_->OnGestureEvent(event);
+}
+
+}  // namespace content