| // Copyright (c) 2012 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. |
| |
| #ifndef CONTENT_PUBLIC_RENDERER_RENDER_VIEW_OBSERVER_H_ |
| #define CONTENT_PUBLIC_RENDERER_RENDER_VIEW_OBSERVER_H_ |
| |
| #include "base/compiler_specific.h" |
| #include "base/macros.h" |
| #include "content/common/content_export.h" |
| #include "content/public/common/page_visibility_state.h" |
| #include "ipc/ipc_listener.h" |
| #include "ipc/ipc_sender.h" |
| |
| namespace content { |
| class RenderView; |
| class RenderViewImpl; |
| |
| // Base class for objects that want to filter incoming IPCs, and also get |
| // notified of changes to the frame. |
| class CONTENT_EXPORT RenderViewObserver : public IPC::Listener, |
| public IPC::Sender { |
| public: |
| // A subclass can use this to delete itself. If it does not, the subclass must |
| // always null-check each call to render_view() because the RenderView can |
| // go away at any time. |
| virtual void OnDestruct() = 0; |
| |
| // These match the WebKit API notifications |
| virtual void DidCommitCompositorFrame() {} |
| virtual void DidUpdateMainFrameLayout() {} |
| |
| virtual void OnZoomLevelChanged() {} |
| |
| virtual void OnPageVisibilityChanged(PageVisibilityState visibility_state) {} |
| |
| // IPC::Listener implementation. |
| bool OnMessageReceived(const IPC::Message& message) override; |
| |
| // IPC::Sender implementation. |
| bool Send(IPC::Message* message) override; |
| |
| RenderView* render_view() const; |
| int routing_id() const { return routing_id_; } |
| |
| protected: |
| explicit RenderViewObserver(RenderView* render_view); |
| ~RenderViewObserver() override; |
| |
| // Sets |render_view_| to track. |
| // Removes itself of previous (if any) |render_view_| observer list and adds |
| // to the new |render_view|. Since it assumes that observer outlives |
| // render_view, OnDestruct should be overridden. |
| void Observe(RenderView* render_view); |
| |
| private: |
| friend class RenderViewImpl; |
| |
| // This is called by the RenderView when it's going away so that this object |
| // can null out its pointer. |
| void RenderViewGone(); |
| |
| RenderViewImpl* render_view_; |
| // The routing ID of the associated RenderView. |
| int routing_id_; |
| |
| DISALLOW_COPY_AND_ASSIGN(RenderViewObserver); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_PUBLIC_RENDERER_RENDER_VIEW_OBSERVER_H_ |