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POYet another getView called multiple times
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  1. POYet another getView called multiple times
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    copied!<p>Each item in my <code>ListView</code> containt an <code>ImageView</code> and a <code>TextView</code>, this will be filled with remote information.</p> <p>I got an URL for the <code>ImageView</code>, therefore I start an <code>AsyncTask</code> which downloads the image and will call <code>setImageBitmap</code> with the downloaded bitmap.</p> <p>This goes very well but when the ListView is created, the <code>getView()</code> is called to often. It calls about 7 times the <code>getView</code> for the first 10 rows (only 7 visible). (So: 0, 1, etc, 10, 0, 1 etc).</p> <p>Then I can just scroll smoothly to the 10th item. But after that, for each new row the listview calls again about 7 times the <code>getView</code> for the first 10 items. (This will cause lag..)</p> <p>But when I remove the <code>setImageBitmap</code> from the <code>AsyncTask</code>, this all won't happen!</p> <p>What could be the problem? Could it be that some layout is to big which will cause another streak of getViews ?</p> <p>Here some code:</p> <pre><code>&lt;ListView android:id="@+id/mylist" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_alignParentBottom="true" android:layout_below="@+id/mydivider" android:divider="@+color/mycolor" android:dividerHeight="2dp" android:fadingEdge="none" android:fastScrollEnabled="true" android:listSelector="@android:color/transparent" android:scrollbars="horizontal" android:scrollingCache="false" android:smoothScrollbar="false" /&gt; </code></pre> <p>The AsyncTask:</p> <pre><code>public static class MyTask extends AsyncTask&lt;String, Integer, Bitmap&gt; { private LruCache&lt;String, Bitmap&gt; mMap; private String mUri; private int mPosition; private ViewHolder mHolder; public MyTask (ViewHolder holder, int position, LruCache&lt;String, Bitmap&gt; map) { mMap = map; mHolder = holder; mPosition = position; } @Override protected Bitmap doInBackground(String... url) { mUri = url[0]; return getBitmapFromURL(mUri); } @Override protected void onPostExecute(Bitmap b) { if (b != null) { mMap.put(mUri, b); if (mPosition == mHolder.position) { holder.image.setImageBitmap(b); } } }; } </code></pre> <p>getView()</p> <pre><code>row = convertView; ViewHolder holder; if (row == null) { row = vi.inflate(R.layout.mylayout, null); holder = new ViewHolder(); holder.image = (ImageView) row.findViewById(R.id.myimage); holder.title = (TextView) row.findViewById(R.id.mytext); row.setTag(holder); } else { holder = (ViewHolder) row.getTag(); } holder.title.setText("text"); holder.image.setImageResource(R.drawable.mydefaulticon); holder.position = position; startMyTask(content, holder, position); </code></pre> <p>Some more information:</p> <p>When an new view is created the stacktrace shown the getView was called from <code>ListView.makeAndAddView()</code> But in the useless streak of getViews it is coming from <code>ListView.measureHeigthOfChildren()</code></p> <p>So it seems like the layout is changed when I set the Bitmap...</p>
 

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