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copied!<p>You are correct that <code>ListView</code> is reusing views in different places on the screen. It's an optimization to keep memory use reasonable and speedy by not allocating new views all the time.</p> <p>Chances are that you're using <code>LiewView</code> incorrectly. Watch <a href="http://www.youtube.com/watch?v=wDBM6wVEO70" rel="noreferrer">this talk on how to properly use <code>ListView</code></a> to get the whole story, but here's the highlights:</p> <ol> <li>"Position" refers to the location of your data in the adapter list. If your adapter data is in an array, this would be the index into that array.</li> <li>"ID" refers to the value of the data itself. If you have a list of names and resort them, their position will change, but their ID will not.</li> <li>"Index" refers to the relative location of a view with respect to the viewable screen area. You'll probably never need this.</li> <li>Do not manipulate views (or attempt to cache them) outside of your adapter's <code>getView()</code> method or you will get strange behavior.</li> <li>If the call to <code>getView(int, View, ViewGroup)</code> provides a view instance, populate its fields instead of inflating totally new views. Assuming you've correctly implemented <code>getItemType()</code>, you'll always get the right <code>View</code> type to repopulate. </li> <li>Make your <code>getView()</code> method as fast as you possibly can, and only do heavy lifting on other threads.</li> <li>Just because the container called <code>getView()</code> doesn't necessarily mean the data will be displayed. The framework uses these for measurement purposes. Since the work could be thrown away, this is another reason to make sure that <code>getView()</code> is as fast as you can make it.</li> <li>When something happens to your data which you need to show on screen, say your download is complete, that's when you call <code>notifyDataSetChanged()</code>. Don't fiddle with the views directly, they'll be populated on the next UI loop when it gets redrawn.</li> </ol> <p>Having just spent a few days reworking a <code>ListView</code> that was implemented naively, I feel your pain. The results have been worth it, though!</p>

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