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copied!<p><strong>Rewrite</strong></p> <p>I didn't have much luck with passing the scrolling actions in one ListView to another. So I chose a different method: passing the <code>MotionEvent</code>. This lets each <code>ListView</code> calculate their own smooth scroll, fast scroll, or anything else.</p> <p><strong>First,</strong> we'll need some class variables:</p> <pre><code>ListView listView; ListView listView2; View clickSource; View touchSource; int offset = 0; </code></pre> <p>Every method that I add to <code>listView</code> will be almost identical for <code>listView2</code>, the only difference is that <code>listView2</code> will reference <code>listView</code> (not itself). I didn't include the repetitive <code>listView2</code> code.</p> <p><strong>Second,</strong> let's start with the OnTouchListener:</p> <pre><code>listView = (ListView) findViewById(R.id.engNameList); listView.setOnTouchListener(new OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { if(touchSource == null) touchSource = v; if(v == touchSource) { listView2.dispatchTouchEvent(event); if(event.getAction() == MotionEvent.ACTION_UP) { clickSource = v; touchSource = null; } } return false; } }); </code></pre> <p>To prevent circular logic: <code>listView</code> calls <code>listView2</code> calls <code>listView</code> calls... I used a class variable <code>touchSource</code> to determine when a <code>MotionEvent</code> should be passed. I assumed that you don't want a row click in <code>listView</code> to also click in <code>listView2</code>, so I used another class variable <code>clickSource</code> to prevent this. </p> <p><strong>Third,</strong> the OnItemClickListener:</p> <pre><code>listView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { if(parent == clickSource) { // Do something with the ListView was clicked } } }); </code></pre> <p><strong>Fourth,</strong> passing every touch event isn't perfect because occasional discrepancies appear. The OnScrollListener is perfect for eliminating these:</p> <pre><code>listView.setOnScrollListener(new OnScrollListener() { @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { if(view == clickSource) listView2.setSelectionFromTop(firstVisibleItem, view.getChildAt(0).getTop() + offset); } @Override public void onScrollStateChanged(AbsListView view, int scrollState) {} }); </code></pre> <p><strong>(Optional) Lastly,</strong> you mentioned that you have trouble since <code>listView</code> and <code>listView2</code> begin at different heights in your layout... I <strong>highly</strong> recommend modifying your layout to balance the ListViews, but I found a way to address this. However it is a little tricky.<br> You cannot calculate the difference in height between the two layouts until after the entire layout have been rendered, but there is no callback for this moment... so I use a simple handler:</p> <pre><code>Handler handler = new Handler() { @Override public void handleMessage(Message msg) { // Set listView's x, y coordinates in loc[0], loc[1] int[] loc = new int[2]; listView.getLocationInWindow(loc); // Save listView's y and get listView2's coordinates int firstY = loc[1]; listView2.getLocationInWindow(loc); offset = firstY - loc[1]; //Log.v("Example", "offset: " + offset + " = " + firstY + " + " + loc[1]); } }; </code></pre> <p>I <em>assume</em> that a half second delay is long enough to render the layout and start the timer in <code>onResume()</code>:</p> <pre><code>handler.sendEmptyMessageDelayed(0, 500); </code></pre> <p>If you do use an offset I want to be clear that <code>listView2</code>'s OnScroll method subtracts the offset rather than adds it:</p> <pre><code>listView2.setSelectionFromTop(firstVisibleItem, view.getChildAt(0).getTop() - offset); </code></pre> <p>Hope that helps!</p>

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