title: Setting Scroller on TextView for vertical scrolling
body: <p>I am trying to implement a sort of vertical scrolling TextView by setting a Scroller on it.  The following code works on my device which runs Android 2.3 but it does not work on devices running Android level 15.  Any ideas why?</p>
  
  <pre><code>Private TextView tenthsTxt;
  Private Scroller tenthsScroller;
  ....
  
  tenthsTxt = (TextView)findViewById(R.id.tenths);
  LinearInterpolator scrollerInterpolator = new LinearInterpolator();
  tenthsScroller = new Scroller(this, scrollerInterpolator);
  tenthsTxt.setScroller(tenthsScroller);
  tenthsScroller.startScroll(0,0,0, 59);
  tenthsTxt.invalidate();
  
  ....
  </code></pre>
  
  <p>The xml for the TextView looks like this:</p>
  
  <pre><code>    &lt;TextView 
      android:id="@+id/tenths"
      android:background="@drawable/tenths_digit_holder"
      android:text="0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n0"
      android:textSize="25dp"
      android:gravity="center"
      android:paddingTop="5dp"
      android:paddingBottom= "5dp"        
      android:layout_width = "30dp"
      android:textStyle="normal"
      android:layout_height="43dp"                
      android:textColor="#ffff0000" /&gt;
  </code></pre>
  
  <p>On Android 2.3 the TextView scrolls vertically by the correct amount.  On Android devices running 4.03 the TextView does not scroll at all.  To be sure, a y-displacement scaled to the pixelDensity of the devices was also used - the results were the same with no scrolling movement observed on Android 4.03 devices.</p>