content/renderer/web_ui_mojo.h

   1 // Copyright 2014 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_RENDERER_WEB_UI_MOJO_H_
   6 #define CONTENT_RENDERER_WEB_UI_MOJO_H_
   7
   8 #include <string>
   9
  10 #include "content/public/renderer/render_frame_observer.h"
  11 #include "content/public/renderer/render_view_observer.h"
  12 #include "content/public/renderer/render_view_observer_tracker.h"
  13 #include "mojo/public/cpp/system/core.h"
  14
  15 namespace gin {
  16 class PerContextData;
  17 }
  18
  19 namespace content {
  20
  21 class WebUIMojoContextState;
  22
  23 // WebUIMojo is responsible for enabling the renderer side of mojo bindings.
  24 // It creates (and destroys) a WebUIMojoContextState at the appropriate times
  25 // and handles the necessary browser messages. WebUIMojo destroys itself when
  26 // the RendererView it is created with is destroyed.
  27 class WebUIMojo
  28     : public RenderViewObserver,
  29       public RenderViewObserverTracker<WebUIMojo> {
  30  public:
  31   explicit WebUIMojo(RenderView* render_view);
  32
  33   // Sets the handle to the current WebUI.
  34   void SetBrowserHandle(mojo::ScopedMessagePipeHandle handle);
  35
  36  private:
  37   class MainFrameObserver : public RenderFrameObserver {
  38    public:
  39     explicit MainFrameObserver(WebUIMojo* web_ui_mojo);
  40     virtual ~MainFrameObserver();
  41
  42     // RenderFrameObserver overrides:
  43     virtual void WillReleaseScriptContext(v8::Handle<v8::Context> context,
  44                                           int world_id) OVERRIDE;
  45     virtual void DidFinishDocumentLoad() OVERRIDE;
  46
  47    private:
  48     WebUIMojo* web_ui_mojo_;
  49
  50     DISALLOW_COPY_AND_ASSIGN(MainFrameObserver);
  51   };
  52
  53   virtual ~WebUIMojo();
  54
  55   void CreateContextState();
  56   void DestroyContextState(v8::Handle<v8::Context> context);
  57
  58   // Invoked when the frame finishes loading. Invokes SetHandleOnContextState()
  59   // if necessary.
  60   void OnDidFinishDocumentLoad();
  61
  62   // Invokes SetHandle() on the WebUIMojoContextState (if there is one).
  63   void SetHandleOnContextState(mojo::ScopedMessagePipeHandle handle);
  64
  65   WebUIMojoContextState* GetContextState();
  66
  67   // RenderViewObserver overrides:
  68   virtual void DidClearWindowObject(blink::WebLocalFrame* frame,
  69                                     int world_id) OVERRIDE;
  70
  71   MainFrameObserver main_frame_observer_;
  72
  73   // Set to true in DidFinishDocumentLoad(). 'main' is only executed once this
  74   // happens.
  75   bool did_finish_document_load_;
  76
  77   // If SetBrowserHandle() is invoked before the document finishes loading the
  78   // MessagePipeHandle is stored here. When the document finishes loading
  79   // SetHandleOnContextState() is invoked to send the handle to the
  80   // WebUIMojoContextState and ultimately the page.
  81   mojo::ScopedMessagePipeHandle pending_handle_;
  82
  83   DISALLOW_COPY_AND_ASSIGN(WebUIMojo);
  84 };
  85
  86 }  // namespace content
  87
  88 #endif  // CONTENT_RENDERER_WEB_UI_MOJO_H_