Make WebUI objects not derive from WebUI. WebUI objects own the controller. This is the ownership...

content/browser/webui/web_ui.cc

 // Copyright (c) 2011 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/webui/web_ui.h"
 
 #include "base/command_line.h"
 #include "base/json/json_writer.h"
 #include "base/stl_util.h"
 #include "base/utf_string_conversions.h"
@@ skipping 23 matching lines @@
     if (i > 0)
       parameters += char16(',');
 
     base::JSONWriter::Write(arg_list[i], false, &json);
     parameters += UTF8ToUTF16(json);
   }
   return ASCIIToUTF16(function_name) +
       char16('(') + parameters + char16(')') + char16(';');
 }
 
-WebUI::WebUI(WebContents* contents,
-             WebUIController* controller)
-    : hide_favicon_(false),
-      focus_location_bar_by_default_(false),
+WebUI::WebUI(WebContents* contents)
+    : focus_location_bar_by_default_(false),
       should_hide_url_(false),
       link_transition_type_(content::PAGE_TRANSITION_LINK),
       bindings_(content::BINDINGS_POLICY_WEB_UI),
       register_callback_overwrites_(false),
-      web_contents_(contents),
-      controller_(controller) {
+      web_contents_(contents) {
   DCHECK(contents);
   AddMessageHandler(new GenericHandler());
 }
 
 WebUI::~WebUI() {
+  // Delete the controller first, since it may also be keeping a pointer to some
+  // of the handlers and can call them at destruction.
+  controller_.reset();
   STLDeleteContainerPointers(handlers_.begin(), handlers_.end());
 }
 
 // WebUI, public: -------------------------------------------------------------
 
 const WebUI::TypeID WebUI::kNoWebUI = NULL;
 
 bool WebUI::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(WebUI, message)
@@ skipping 39 matching lines @@
 #endif  // defined(TOOLKIT_VIEWS)
 
   // Let the WebUI know that we're looking for UI that's optimized for touch
   // input.
   // TODO(rbyers) Figure out the right model for enabling touch-optimized UI
   // (http://crbug.com/105380).
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kTouchOptimizedUI))
     render_view_host->SetWebUIProperty("touchOptimized", "true");
 }
 
+WebContents* WebUI::GetWebContents() const {
+  return web_contents_;
+}
+
+bool WebUI::ShouldHideFavicon() const {
+  return hide_favicon_;
+}
+
+void WebUI::HideFavicon() {
+  hide_favicon_ = true;
+}
+
+bool WebUI::ShouldFocusLocationBarByDefault() const {
+  return focus_location_bar_by_default_;
+}
+
+void WebUI::FocusLocationBarByDefault() {
+  focus_location_bar_by_default_ = true;
+}
+
+bool WebUI::ShouldHideURL() const {
+  return should_hide_url_;
+}
+
+void WebUI::HideURL() {
+  should_hide_url_ = true;
+}
+
+const string16& WebUI::GetOverriddenTitle() const {
+  return overridden_title_;
+}
+
+void WebUI::OverrideTitle(const string16& title) {
+  overridden_title_ = title;
+}
+
+content::PageTransition WebUI::GetLinkTransitionType() const {
+  return link_transition_type_;
+}
+
+void WebUI::SetLinkTransitionType(content::PageTransition type) {
+  link_transition_type_ = type;
+}
+
+int WebUI::GetBindings() const {
+  return bindings_;
+}
+
+void WebUI::SetBindings(int bindings) {
+  bindings_ = bindings;
+}
+
+void WebUI::SetFrameXPath(const std::string& xpath) {
+  frame_xpath_ = xpath;
+}
+
+WebUIController* WebUI::GetController() const {
+  return controller_.get();
+}
+
+void WebUI::SetController(WebUIController* controller) {
+  controller_.reset(controller);

[Jói, 2012/01/17 17:34:05]

There might be a bug here w.r.t. the ownership model:  You're destroying the
controller in the destructor, implying that you take over ownership of
controller_, so here you should probably delete the existing controller_ if it
is non-NULL before resetting it.

[jam, 2012/01/17 17:38:35]

scoped_ptr::reset() does that :)

+}
+
 void WebUI::CallJavascriptFunction(const std::string& function_name) {
   DCHECK(IsStringASCII(function_name));
   string16 javascript = ASCIIToUTF16(function_name + "();");
   ExecuteJavascript(javascript);
 }
 
 void WebUI::CallJavascriptFunction(const std::string& function_name,
                                    const Value& arg) {
   DCHECK(IsStringASCII(function_name));
   std::vector<const Value*> args;
@@ skipping 60 matching lines @@
   DCHECK(!handler->web_ui());
   handler->set_web_ui(this);
   handler->RegisterMessages();
   handlers_.push_back(handler);
 }
 
 void WebUI::ExecuteJavascript(const string16& javascript) {
   web_contents_->GetRenderViewHost()->ExecuteJavascriptInWebFrame(
       ASCIIToUTF16(frame_xpath_), javascript);
 }