Line data    Source code

       1             : /* vim: se cin sw=2 ts=2 et : */
       2             : /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
       3             :  *
       4             :  * This Source Code Form is subject to the terms of the Mozilla Public
       5             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       6             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       7             : 
       8             : #ifndef __mozilla_widget_GfxInfoCollector_h__
       9             : #define __mozilla_widget_GfxInfoCollector_h__
      10             : 
      11             : #include "mozilla/Attributes.h"
      12             : #include "nsStringFwd.h"
      13             : #include "js/RootingAPI.h"
      14             : 
      15             : namespace mozilla {
      16             : namespace widget {
      17             : 
      18             : 
      19             : /* this is handy wrapper around JSAPI to make it more pleasant to use.
      20             :  * We collect the JSAPI errors and so that callers don't need to */
      21           0 : class MOZ_STACK_CLASS InfoObject
      22             : {
      23             :   friend class GfxInfoBase;
      24             : 
      25             :   public:
      26             :   void DefineProperty(const char *name, int value);
      27             :   void DefineProperty(const char *name, nsAString &value);
      28             :   void DefineProperty(const char *name, const char *value);
      29             : 
      30             :   private:
      31             :   // We need to ensure that this object lives on the stack so that GC sees it properly
      32             :   explicit InfoObject(JSContext *aCx);
      33             :   InfoObject(InfoObject&);
      34             : 
      35             :   JSContext *mCx;
      36             :   JS::Rooted<JSObject*> mObj;
      37             :   bool mOk;
      38             : };
      39             : 
      40             : /*
      41             : 
      42             :    Here's an example usage:
      43             : 
      44             :    class Foo {
      45             :    Foo::Foo() : mInfoCollector(this, &Foo::GetAweseomeness) {}
      46             : 
      47             :    void GetAwesomeness(InfoObject &obj) {
      48             :      obj.DefineProperty("awesome", mAwesome);
      49             :    }
      50             : 
      51             :    int mAwesome;
      52             : 
      53             :    GfxInfoCollector<Foo> mInfoCollector;
      54             :    }
      55             : 
      56             :    This will define a property on the object
      57             :    returned from calling getInfo() on a
      58             :    GfxInfo object. e.g.
      59             : 
      60             :        gfxInfo = Cc["@mozilla.org/gfx/info;1"].getService(Ci.nsIGfxInfo);
      61             :        info = gfxInfo.getInfo();
      62             :        if (info.awesome)
      63             :           alert(info.awesome);
      64             : 
      65             : */
      66             : 
      67             : class GfxInfoCollectorBase
      68             : {
      69             :   public:
      70             :   GfxInfoCollectorBase();
      71             :   virtual void GetInfo(InfoObject &obj) = 0;
      72             :   virtual ~GfxInfoCollectorBase();
      73             : };
      74             : 
      75             : template<class T>
      76           0 : class GfxInfoCollector : public GfxInfoCollectorBase
      77             : {
      78             :   public:
      79           9 :   GfxInfoCollector(T* aPointer, void (T::*aFunc)(InfoObject &obj)) : mPointer(aPointer), mFunc(aFunc) {
      80           9 :   }
      81           0 :   virtual void GetInfo(InfoObject &obj) override {
      82           0 :     (mPointer->*mFunc)(obj);
      83           0 :   }
      84             : 
      85             :   protected:
      86             :   T* mPointer;
      87             :   void (T::*mFunc)(InfoObject &obj);
      88             : 
      89             : };
      90             : 
      91             : } // namespace widget
      92             : } // namespace mozilla
      93             : 
      94             : #endif