content/renderer/web_ui_mojo.cc

   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 #include "content/renderer/web_ui_mojo.h"
   6
   7 #include "content/common/view_messages.h"
   8 #include "content/public/renderer/render_frame.h"
   9 #include "content/public/renderer/render_view.h"
  10 #include "content/renderer/web_ui_mojo_context_state.h"
  11 #include "gin/per_context_data.h"
  12 #include "third_party/WebKit/public/web/WebKit.h"
  13 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  14 #include "third_party/WebKit/public/web/WebView.h"
  15 #include "v8/include/v8.h"
  16
  17 namespace content {
  18
  19 namespace {
  20
  21 const char kWebUIMojoContextStateKey[] = "WebUIMojoContextState";
  22
  23 struct WebUIMojoContextStateData : public base::SupportsUserData::Data {
  24   scoped_ptr<WebUIMojoContextState> state;
  25 };
  26
  27 }  // namespace
  28
  29 WebUIMojo::MainFrameObserver::MainFrameObserver(WebUIMojo* web_ui_mojo)
  30     : RenderFrameObserver(RenderFrame::FromWebFrame(
  31           web_ui_mojo->render_view()->GetWebView()->mainFrame())),
  32       web_ui_mojo_(web_ui_mojo) {
  33 }
  34
  35 WebUIMojo::MainFrameObserver::~MainFrameObserver() {
  36 }
  37
  38 void WebUIMojo::MainFrameObserver::WillReleaseScriptContext(
  39     v8::Handle<v8::Context> context,
  40     int world_id) {
  41   web_ui_mojo_->DestroyContextState(context);
  42 }
  43
  44 void WebUIMojo::MainFrameObserver::DidFinishDocumentLoad() {
  45   web_ui_mojo_->OnDidFinishDocumentLoad();
  46 }
  47
  48 WebUIMojo::WebUIMojo(RenderView* render_view)
  49     : RenderViewObserver(render_view),
  50       RenderViewObserverTracker<WebUIMojo>(render_view),
  51       main_frame_observer_(this) {
  52 }
  53
  54 WebUIMojo::~WebUIMojo() {
  55 }
  56
  57 void WebUIMojo::CreateContextState() {
  58   v8::HandleScope handle_scope(blink::mainThreadIsolate());
  59   blink::WebLocalFrame* frame =
  60       render_view()->GetWebView()->mainFrame()->toWebLocalFrame();
  61   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
  62   gin::PerContextData* context_data = gin::PerContextData::From(context);
  63   WebUIMojoContextStateData* data = new WebUIMojoContextStateData;
  64   data->state.reset(new WebUIMojoContextState(
  65                         render_view()->GetWebView()->mainFrame(), context));
  66   context_data->SetUserData(kWebUIMojoContextStateKey, data);
  67 }
  68
  69 void WebUIMojo::DestroyContextState(v8::Handle<v8::Context> context) {
  70   gin::PerContextData* context_data = gin::PerContextData::From(context);
  71   if (!context_data)
  72     return;
  73   context_data->RemoveUserData(kWebUIMojoContextStateKey);
  74 }
  75
  76 void WebUIMojo::OnDidFinishDocumentLoad() {
  77   v8::HandleScope handle_scope(blink::mainThreadIsolate());
  78   WebUIMojoContextState* state = GetContextState();
  79   if (state)
  80     state->Run();
  81 }
  82
  83 WebUIMojoContextState* WebUIMojo::GetContextState() {
  84   blink::WebLocalFrame* frame =
  85       render_view()->GetWebView()->mainFrame()->toWebLocalFrame();
  86   v8::HandleScope handle_scope(blink::mainThreadIsolate());
  87   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
  88   gin::PerContextData* context_data = gin::PerContextData::From(context);
  89   if (!context_data)
  90     return NULL;
  91   WebUIMojoContextStateData* context_state =
  92       static_cast<WebUIMojoContextStateData*>(
  93           context_data->GetUserData(kWebUIMojoContextStateKey));
  94   return context_state ? context_state->state.get() : NULL;
  95 }
  96
  97 void WebUIMojo::DidCreateDocumentElement(blink::WebLocalFrame* frame) {
  98   CreateContextState();
  99 }
 100
 101 void WebUIMojo::DidClearWindowObject(blink::WebLocalFrame* frame) {
 102   if (frame != render_view()->GetWebView()->mainFrame())
 103     return;
 104
 105   // NOTE: this function may be called early on twice. From the constructor
 106   // mainWorldScriptContext() may trigger this to be called. If we are created
 107   // before the page is loaded (which is very likely), then on first load this
 108   // is called. In the case of the latter we may have already supplied the
 109   // handle to the context state so that if we destroy now the handle is
 110   // lost. If this is the result of the first load then the contextstate should
 111   // be empty and we don't need to destroy it.
 112   WebUIMojoContextState* state = GetContextState();
 113   if (state && !state->module_added())
 114     return;
 115
 116   v8::HandleScope handle_scope(blink::mainThreadIsolate());
 117   DestroyContextState(frame->mainWorldScriptContext());
 118 }
 119
 120 }  // namespace content