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32<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QImageConsumer Class Reference</h1>
33
34<p>The QImageConsumer class is an abstraction used by QImageDecoder.
35<a href="#details">More...</a>
36<p><tt>#include &lt;<a href="qasyncimageio-h.html">qasyncimageio.h</a>&gt;</tt>
37<p><a href="qimageconsumer-members.html">List of all member functions.</a>
38<h2>Public Members</h2>
39<ul>
40<li class=fn>virtual void <a href="#end"><b>end</b></a> () = 0</li>
41<li class=fn>virtual void <a href="#changed"><b>changed</b></a> ( const QRect &amp; ) = 0</li>
42<li class=fn>virtual void <a href="#frameDone"><b>frameDone</b></a> () = 0</li>
43<li class=fn>virtual void <a href="#frameDone-2"><b>frameDone</b></a> ( const&nbsp;QPoint&nbsp;&amp;&nbsp;offset, const&nbsp;QRect&nbsp;&amp;&nbsp;rect ) = 0</li>
44<li class=fn>virtual void <a href="#setLooping"><b>setLooping</b></a> ( int&nbsp;n ) = 0</li>
45<li class=fn>virtual void <a href="#setFramePeriod"><b>setFramePeriod</b></a> ( int&nbsp;milliseconds ) = 0</li>
46<li class=fn>virtual void <a href="#setSize"><b>setSize</b></a> ( int, int ) = 0</li>
47</ul>
48<hr><a name="details"></a><h2>Detailed Description</h2>
49
50
51The QImageConsumer class is an abstraction used by <a href="qimagedecoder.html">QImageDecoder</a>.
52<p>
53
54
55<p> The <a href="qmovie.html">QMovie</a> class, or <a href="qlabel.html#setMovie">QLabel::setMovie</a>(), are easy to use and for
56most situations do what you want with regards animated images.
57<p> A QImageConsumer consumes information about changes to the <a href="qimage.html">QImage</a>
58maintained by a QImageDecoder. Think of the QImage as the model or
59source of the image data, with the QImageConsumer as a view of
60that data and the QImageDecoder being the controller that
61orchestrates the relationship between the model and the view.
62<p> You'd use the QImageConsumer class, for example, if you were
63implementing a web browser with your own image loaders.
64<p> <p>See also <a href="qimagedecoder.html">QImageDecoder</a>, <a href="graphics.html">Graphics Classes</a>, <a href="images.html">Image Processing Classes</a>, and <a href="multimedia.html">Multimedia Classes</a>.
65
66<hr><h2>Member Function Documentation</h2>
67<h3 class=fn>void <a name="changed"></a>QImageConsumer::changed ( const&nbsp;<a href="qrect.html">QRect</a>&nbsp;&amp; )<tt> [pure virtual]</tt>
68</h3>
69
70<p> Called when the given area of the image has changed.
71
72<h3 class=fn>void <a name="end"></a>QImageConsumer::end ()<tt> [pure virtual]</tt>
73</h3>
74
75<p> Called when all the data from all the frames has been decoded and
76revealed as <a href="#changed">changed</a>().
77
78<h3 class=fn>void <a name="frameDone"></a>QImageConsumer::frameDone ()<tt> [pure virtual]</tt>
79</h3>
80
81<p> One of the two <a href="#frameDone">frameDone</a>() functions will be called when a frame
82of an animated image has ended and been revealed as <a href="#changed">changed</a>().
83<p> When this function is called, the current image should be
84displayed.
85<p> The decoder will not make any further changes to the image until
86the next call to <a href="qimageformat.html#decode">QImageFormat::decode</a>().
87
88<h3 class=fn>void <a name="frameDone-2"></a>QImageConsumer::frameDone ( const&nbsp;<a href="qpoint.html">QPoint</a>&nbsp;&amp;&nbsp;offset, const&nbsp;<a href="qrect.html">QRect</a>&nbsp;&amp;&nbsp;rect )<tt> [pure virtual]</tt>
89</h3>
90This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
91<p> One of the two <a href="#frameDone">frameDone</a>() functions will be called when a frame
92of an animated image has ended and been revealed as <a href="#changed">changed</a>().
93<p> When this function is called, the area <em>rect</em> in the current
94image should be moved by <em>offset</em> and displayed.
95<p> The decoder will not make any further changes to the image until
96the next call to <a href="qimageformat.html#decode">QImageFormat::decode</a>().
97
98<h3 class=fn>void <a name="setFramePeriod"></a>QImageConsumer::setFramePeriod ( int&nbsp;milliseconds )<tt> [pure virtual]</tt>
99</h3>
100
101<p> Notes that the frame about to be decoded should not be displayed
102until the given number of <em>milliseconds</em> after the time that this
103function is called. Of course, the image may not have been
104decoded by then, in which case the frame should not be displayed
105until it is complete. A value of -1 (the assumed default)
106indicates that the image should be displayed even while it is only
107partially loaded.
108
109<h3 class=fn>void <a name="setLooping"></a>QImageConsumer::setLooping ( int&nbsp;n )<tt> [pure virtual]</tt>
110</h3>
111
112<p> Called to indicate that the sequence of frames in the image
113should be repeated <em>n</em> times, including the sequence during
114decoding.
115<p> <ul>
116<li> 0 = Forever
117<li> 1 = Only display frames the first time through
118<li> 2 = Repeat once after first pass through images
119<li> etc.
120</ul>
121<p> To make the <a href="qimagedecoder.html">QImageDecoder</a> do this, just delete it and pass the
122information to it again for decoding (<a href="#setLooping">setLooping</a>() will be called
123again, of course, but that can be ignored), or keep copies of the
124changed areas at the ends of frames.
125
126<h3 class=fn>void <a name="setSize"></a>QImageConsumer::setSize ( int, int )<tt> [pure virtual]</tt>
127</h3>
128
129<p> This function is called as soon as the size of the image has been
130determined.
131
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