content/public/browser/web_ui.h

   1 // Copyright (c) 2012 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_PUBLIC_BROWSER_WEB_UI_H_
   6 #define CONTENT_PUBLIC_BROWSER_WEB_UI_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/callback.h"
  12 #include "base/strings/string16.h"
  13 #include "content/common/content_export.h"
  14 #include "ui/base/page_transition_types.h"
  15
  16 class GURL;
  17
  18 namespace base {
  19 class ListValue;
  20 class Value;
  21 }
  22
  23 namespace content {
  24
  25 class WebContents;
  26 class WebUIController;
  27 class WebUIMessageHandler;
  28
  29 // A WebUI sets up the datasources and message handlers for a given HTML-based
  30 // UI.
  31 class CONTENT_EXPORT WebUI {
  32  public:
  33   // An opaque identifier used to identify a WebUI. This can only be compared to
  34   // kNoWebUI or other WebUI types. See GetWebUIType.
  35   typedef void* TypeID;
  36
  37   // A special WebUI type that signifies that a given page would not use the
  38   // Web UI system.
  39   static const TypeID kNoWebUI;
  40
  41   // Returns JavaScript code that, when executed, calls the function specified
  42   // by |function_name| with the arguments specified in |arg_list|.
  43   static base::string16 GetJavascriptCall(
  44       const std::string& function_name,
  45       const std::vector<const base::Value*>& arg_list);
  46
  47   virtual ~WebUI() {}
  48
  49   virtual WebContents* GetWebContents() const = 0;
  50
  51   virtual WebUIController* GetController() const = 0;
  52   virtual void SetController(WebUIController* controller) = 0;
  53
  54   // Returns the device scale factor of the monitor that the renderer is on.
  55   // Whenever possible, WebUI should push resources with this scale factor to
  56   // Javascript.
  57   virtual float GetDeviceScaleFactor() const = 0;
  58
  59   // Gets a custom tab title provided by the Web UI. If there is no title
  60   // override, the string will be empty which should trigger the default title
  61   // behavior for the tab.
  62   virtual const base::string16& GetOverriddenTitle() const = 0;
  63   virtual void OverrideTitle(const base::string16& title) = 0;
  64
  65   // Returns the transition type that should be used for link clicks on this
  66   // Web UI. This will default to LINK but may be overridden.
  67   virtual ui::PageTransition GetLinkTransitionType() const = 0;
  68   virtual void SetLinkTransitionType(ui::PageTransition type) = 0;
  69
  70   // Allows a controller to override the BindingsPolicy that should be enabled
  71   // for this page.
  72   virtual int GetBindings() const = 0;
  73   virtual void SetBindings(int bindings) = 0;
  74
  75   // Overrides which frame gets JavaScript messages; this is useful if this
  76   // WebUI is embedded in a page. If no override is set, the main frame will
  77   // receive the JavaScript messages.
  78   virtual void OverrideJavaScriptFrame(const std::string& frame_name) = 0;
  79
  80   // Takes ownership of |handler|, which will be destroyed when the WebUI is.
  81   virtual void AddMessageHandler(WebUIMessageHandler* handler) = 0;
  82
  83   // Used by WebUIMessageHandlers. If the given message is already registered,
  84   // the call has no effect unless |register_callback_overwrites_| is set to
  85   // true.
  86   typedef base::Callback<void(const base::ListValue*)> MessageCallback;
  87   virtual void RegisterMessageCallback(const std::string& message,
  88                                        const MessageCallback& callback) = 0;
  89
  90   // This is only needed if an embedder overrides handling of a WebUIMessage and
  91   // then later wants to undo that, or to route it to a different WebUI object.
  92   virtual void ProcessWebUIMessage(const GURL& source_url,
  93                                    const std::string& message,
  94                                    const base::ListValue& args) = 0;
  95
  96   // Call a Javascript function by sending its name and arguments down to
  97   // the renderer.  This is asynchronous; there's no way to get the result
  98   // of the call, and should be thought of more like sending a message to
  99   // the page.
 100   // All function names in WebUI must consist of only ASCII characters.
 101   // There are variants for calls with more arguments.
 102   virtual void CallJavascriptFunction(const std::string& function_name) = 0;
 103   virtual void CallJavascriptFunction(const std::string& function_name,
 104                                       const base::Value& arg) = 0;
 105   virtual void CallJavascriptFunction(const std::string& function_name,
 106                                       const base::Value& arg1,
 107                                       const base::Value& arg2) = 0;
 108   virtual void CallJavascriptFunction(const std::string& function_name,
 109                                       const base::Value& arg1,
 110                                       const base::Value& arg2,
 111                                       const base::Value& arg3) = 0;
 112   virtual void CallJavascriptFunction(const std::string& function_name,
 113                                       const base::Value& arg1,
 114                                       const base::Value& arg2,
 115                                       const base::Value& arg3,
 116                                       const base::Value& arg4) = 0;
 117   virtual void CallJavascriptFunction(
 118       const std::string& function_name,
 119       const std::vector<const base::Value*>& args) = 0;
 120 };
 121
 122 }  // namespace content
 123
 124 #endif  // CONTENT_PUBLIC_BROWSER_WEB_UI_H_