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copied!<p>As Romain Guy <a href="http://www.youtube.com/watch?v=wDBM6wVEO70&t=45m46s" rel="noreferrer">explained a while back</a> during the <a href="http://www.google.com/events/io/2010/sessions/world-of-listview-android.html" rel="noreferrer">Google I/O session</a>, the most efficient way to only update one view in a list view is something like the following (this one update the whole view data):</p> <pre><code>ListView list = getListView(); int start = list.getFirstVisiblePosition(); for(int i=start, j=list.getLastVisiblePosition();i<=j;i++) if(target==list.getItemAtPosition(i)){ View view = list.getChildAt(i-start); list.getAdapter().getView(i, view, list); break; } </code></pre> <p>Assuming <code>target</code> is one item of the adapter.</p> <p>This code retrieve the <code>ListView</code>, then browse the currently shown views, compare the <code>target</code> item you are looking for with each displayed view items, and if your target is among those, get the enclosing view and execute the adapter <code>getView</code> on that view to refresh the display.</p> <p>As a side note <code>invalidate</code> doesn't work like some people expect and will not refresh the view like getView does, <code>notifyDataSetChanged</code> will rebuild the whole list and end up calling <code>getview</code> for every displayed items and <code>invalidateViews</code> will also affect a bunch.</p> <p>One last thing, one can also get extra performance if he only needs to change a child of a row view and not the whole row like <code>getView</code> does. In that case, the following code can replace <code>list.getAdapter().getView(i, view, list);</code> (example to change a <code>TextView</code> text):</p> <pre><code>((TextView)view.findViewById(R.id.myid)).setText("some new text"); </code></pre> <p>In code we trust.</p>

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