Initial implementation of WebUI generator (WUG) toolkit.

components/wug/web_ui_view.h

+// Copyright 2015 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 CHROME_BROWSER_UI_WEBUI_WUG_WEB_UI_VIEW_H_
+#define CHROME_BROWSER_UI_WEBUI_WUG_WEB_UI_VIEW_H_
+
+#include <string>
+
+#include "base/bind.h"
+#include "base/containers/hash_tables.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted_memory.h"
+#include "base/memory/scoped_ptr.h"
+#include "components/login/base_screen_handler_utils.h"
+#include "components/login/screens/screen_context.h"
+#include "components/wug/export.h"
+#include "components/wug/view.h"
+#include "content/public/browser/web_ui.h"
+#include "content/public/browser/web_ui_data_source.h"
+
+namespace base {
+class DictionaryValue;
+}
+
+namespace content {
+class WebUI;
+}
+
+namespace login {
+class LocalizedValuesBuilder;
+}
+
+namespace wug {
+
+using Context = login::ScreenContext;
+
+/**
+ * View implementation for the WebUI. Represents a single HTML element derieved
+ * from <web-ui-view>.
+ */
+class WUG_EXPORT WebUIView : public View {
+ public:
+  WebUIView(content::WebUI* web_ui, const std::string& id);
+  ~WebUIView() override;
+
+  // Should be called for |data_source|, where this views will be used.
+  // Sets up |data_source| for children of |this| as well, that is why this
+  // method only shouldn't be called for non-root views.
+  void SetUpDataSource(content::WebUIDataSource* data_source);
+
+  // Overridden from View:
+  void Init() override;
+
+ protected:
+  using ResourcesMap =
+      base::hash_map<std::string, scoped_refptr<base::RefCountedMemory>>;
+
+  content::WebUI* web_ui() { return web_ui_; }
+
+  template <typename T>
+  void AddCallback(const std::string& name, void (T::*method)()) {
+    base::Callback<void()> callback =
+        base::Bind(method, base::Unretained(static_cast<T*>(this)));
+    web_ui_->RegisterMessageCallback(
+        name, base::Bind(&::login::CallbackWrapper0, callback));
+  }
+
+  template <typename T, typename A1>
+  void AddCallback(const std::string& name, void (T::*method)(A1 arg1)) {
+    base::Callback<void(A1)> callback =
+        base::Bind(method, base::Unretained(static_cast<T*>(this)));
+    web_ui_->RegisterMessageCallback(
+        name, base::Bind(&::login::CallbackWrapper1<A1>, callback));
+  }
+
+  // Overridden from View:
+  void OnReady() override;
+  void OnContextChanged(const base::DictionaryValue& diff) override;
+
+  virtual void AddLocalizedValues(::login::LocalizedValuesBuilder* builder) = 0;
+  virtual void AddResources(ResourcesMap* resources_map) = 0;
+
+ private:
+  // Internal implementation of SetUpDataSource.
+  void SetUpDataSourceInternal(content::WebUIDataSource* data_source,
+                               ResourcesMap* resources_map);
+
+  // Called when corresponding <web-ui-view> is ready.
+  void HandleHTMLReady();
+
+  // Called when context is changed on JS side.
+  void HandleContextChanged(const base::DictionaryValue* diff);
+
+  // Called when both |this| and corresponding <web-ui-view> are ready.
+  void Bind();
+
+  // Request filter for data source. Filter is needed to answer with a generated
+  // HTML and JS code which is not kept in resources.
+  bool HandleDataRequest(
+      const ResourcesMap* resources,
+      const std::string& path,
+      const content::WebUIDataSource::GotDataCallback& got_data_callback);
+
+ private:
+  content::WebUI* web_ui_;
+  bool html_ready_;
+  bool view_bound_;
+  scoped_ptr<Context> pending_context_changes_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebUIView);
+};
+
+}  // namespace wug
+
+#endif  // CHROME_BROWSER_UI_WEBUI_WUG_WEB_UI_VIEW_H_