1 /*
2     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
3     Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
4     Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
5 
6     This library is free software; you can redistribute it and/or
7     modify it under the terms of the GNU Library General Public
8     License as published by the Free Software Foundation; either
9     version 2 of the License, or (at your option) any later version.
10 
11     This library is distributed in the hope that it will be useful,
12     but WITHOUT ANY WARRANTY; without even the implied warranty of
13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14     Library General Public License for more details.
15 
16     You should have received a copy of the GNU Library General Public License
17     along with this library; see the file COPYING.LIB.  If not, write to
18     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19     Boston, MA 02110-1301, USA.
20 
21     This class provides all functionality needed for loading images, style sheets and html
22     pages from the web. It has a memory cache for these objects.
23 */
24 
25 #ifndef CachedResourceClient_h
26 #define CachedResourceClient_h
27 
28 #include <wtf/FastAllocBase.h>
29 #include <wtf/Forward.h>
30 
31 namespace WebCore {
32 
33     class CachedCSSStyleSheet;
34     class CachedFont;
35     class CachedResource;
36     class CachedImage;
37     class Image;
38     class IntRect;
39     class KURL;
40 
41     /**
42      * @internal
43      *
44      * a client who wants to load stylesheets, images or scripts from the web has to
45      * inherit from this class and overload one of the 3 functions
46      *
47      */
48     class CachedResourceClient {
49         WTF_MAKE_FAST_ALLOCATED;
50     public:
~CachedResourceClient()51         virtual ~CachedResourceClient() { }
52 
53         // Called whenever a frame of an image changes, either because we got more data from the network or
54         // because we are animating. If not null, the IntRect is the changed rect of the image.
55         virtual void imageChanged(CachedImage*, const IntRect* = 0) { };
56 
57         // Called to find out if this client wants to actually display the image.  Used to tell when we
58         // can halt animation.  Content nodes that hold image refs for example would not render the image,
59         // but RenderImages would (assuming they have visibility: visible and their render tree isn't hidden
60         // e.g., in the b/f cache or in a background tab).
willRenderImage(CachedImage *)61         virtual bool willRenderImage(CachedImage*) { return false; }
62 
setCSSStyleSheet(const String &,const KURL &,const String &,const CachedCSSStyleSheet *)63         virtual void setCSSStyleSheet(const String& /* href */, const KURL& /* baseURL */, const String& /* charset */, const CachedCSSStyleSheet*) { }
setXSLStyleSheet(const String &,const KURL &,const String &)64         virtual void setXSLStyleSheet(const String& /* href */, const KURL& /* baseURL */, const String& /* sheet */) { }
fontLoaded(CachedFont *)65         virtual void fontLoaded(CachedFont*) {};
notifyFinished(CachedResource *)66         virtual void notifyFinished(CachedResource*) { }
67     };
68 
69 }
70 
71 #endif
72