Start renderer in ContentViewCoreImpl::EvaluateJavaScript.

content/browser/android/content_view_core_impl.cc

 // Copyright 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.
 
 #include "content/browser/android/content_view_core_impl.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/android/scoped_java_ref.h"
@@ skipping 1454 matching lines @@
   ScopedJavaLocalRef<jstring> j_json = ConvertUTF8ToJavaString(env, json);
   Java_ContentViewCore_onEvaluateJavaScriptResult(env,
                                                   j_json.obj(),
                                                   callback.obj());
 }
 }  // namespace
 
 void ContentViewCoreImpl::EvaluateJavaScript(JNIEnv* env,
                                              jobject obj,
                                              jstring script,
-                                             jobject callback) {
-  RenderViewHost* host = web_contents_->GetRenderViewHost();
-  DCHECK(host);
+                                             jobject callback,
+                                             jboolean start_renderer) {
+  RenderViewHost* rvh =
+      static_cast<RenderViewHost*>(web_contents_->GetRenderViewHost());
+  DCHECK(rvh);
+
+  WebContentsImpl* web_contents_impl =
+      static_cast<WebContentsImpl*>(web_contents_);

[joth, 2013/08/20 05:00:44]

just use web_contents_  -- it's already of type WebContentsImpl*

[michaelbai, 2013/08/20 19:15:20]

Done.

+  if (start_renderer && !rvh->IsRenderViewLive()) {
+    if (!web_contents_impl->CreateRenderView(rvh, MSG_ROUTING_NONE, -1)) {

[joth, 2013/08/20 05:00:44]

this looks kind of complex, and the change in WebContentsImpl I don't really
understand.

would it work to call CreateSwappedOutRenderView() here? This would give almost
the same callpath, but the RenderViewHostManager would then also be involved.
(It sounds like it should be in the know about this)

[michaelbai, 2013/08/20 19:15:20]

Tried, it didn't work, it seemed that a swapped out RenderView was created, the
JavaScript wasn't sent to this RenderView until it becomes the current one, in
order to make it current, it need to navigate to something, which doesn't meet
our requirement that JavaScript needs executed before a page been loading.

Basically, we need a way to start the RenderView without a navigation entry.

On 2013/08/20 05:00:44, joth wrote:

+      LOG(ERROR) <<
+          "Falied to create RenderView in EvaluateJavaScript";
+      return;
+    }
+  }
 
   if (!callback) {
     // No callback requested.
-    host->ExecuteJavascriptInWebFrame(string16(),  // frame_xpath
-                                      ConvertJavaStringToUTF16(env, script));
+    rvh->ExecuteJavascriptInWebFrame(string16(),  // frame_xpath
+                                     ConvertJavaStringToUTF16(env, script));
     return;
   }
 
   // Secure the Java callback in a scoped object and give ownership of it to the
   // base::Callback.
   ScopedJavaGlobalRef<jobject> j_callback;
   j_callback.Reset(env, callback);
   content::RenderViewHost::JavascriptResultCallback c_callback =
       base::Bind(&JavaScriptResultCallback, j_callback);
 
-  host->ExecuteJavascriptInWebFrameCallbackResult(
+  rvh->ExecuteJavascriptInWebFrameCallbackResult(
       string16(),  // frame_xpath
       ConvertJavaStringToUTF16(env, script),
       c_callback);
 }
 
 bool ContentViewCoreImpl::GetUseDesktopUserAgent(
     JNIEnv* env, jobject obj) {
   NavigationEntry* entry = web_contents_->GetController().GetActiveEntry();
   return entry && entry->GetIsOverridingUserAgent();
 }
@@ skipping 90 matching lines @@
       reinterpret_cast<ui::ViewAndroid*>(view_android),
       reinterpret_cast<ui::WindowAndroid*>(window_android));
   return reinterpret_cast<jint>(view);
 }
 
 bool RegisterContentViewCore(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace content