content/browser/renderer_host/input/input_router_client.h

   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 #ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_CLIENT_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_CLIENT_H_
   7
   8 #include "content/browser/renderer_host/event_with_latency_info.h"
   9 #include "content/common/content_export.h"
  10 #include "content/common/input/input_event_ack_state.h"
  11 #include "content/public/browser/native_web_keyboard_event.h"
  12 #include "third_party/WebKit/public/web/WebInputEvent.h"
  13
  14 namespace ui {
  15 struct LatencyInfo;
  16 }
  17
  18 namespace content {
  19
  20 class OverscrollController;
  21
  22 class CONTENT_EXPORT InputRouterClient {
  23  public:
  24   virtual ~InputRouterClient() {}
  25
  26   // Called just prior to events being sent to the renderer, giving the client
  27   // a chance to perform in-process event filtering.
  28   // The returned disposition will yield the following behavior:
  29   //   * |NOT_CONSUMED| will result in |input_event| being sent as usual.
  30   //   * |CONSUMED| or |NO_CONSUMER_EXISTS| will trigger the appropriate ack.
  31   //   * |UNKNOWN| will result in |input_event| being dropped.
  32   virtual InputEventAckState FilterInputEvent(
  33       const blink::WebInputEvent& input_event,
  34       const ui::LatencyInfo& latency_info) = 0;
  35
  36   // Called each time a WebInputEvent IPC is sent.
  37   virtual void IncrementInFlightEventCount() = 0;
  38
  39   // Called each time a WebInputEvent ACK IPC is received.
  40   virtual void DecrementInFlightEventCount() = 0;
  41
  42   // Called when the renderer notifies that it has touch event handlers.
  43   virtual void OnHasTouchEventHandlers(bool has_handlers) = 0;
  44
  45   // Returns an optional OverscrollController.  If non-NULL, the controller
  46   // will be fed events and event acks by the router, when appropriate.
  47   // TODO(jdduke): crbug.com/306133 - Move the controller to the router.
  48   virtual OverscrollController* GetOverscrollController() const = 0;
  49
  50   // Certain router implementations require periodic flushing of queued events.
  51   // When this method is called, the client should ensure a timely call, either
  52   // synchronous or asynchronous, of |Flush| on the InputRouter.
  53   virtual void SetNeedsFlush() = 0;
  54
  55   // Called when the router has finished flushing all events queued at the time
  56   // of the call to Flush.  The call will typically be asynchronous with
  57   // respect to the call to |Flush| on the InputRouter.
  58   virtual void DidFlush() = 0;
  59 };
  60
  61 } // namespace content
  62
  63 #endif // CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_CLIENT_H_