title: Android ScrollView how to keep component on screen when it scroll to top of the screen?
body: <p>I have a ScrollView layout like this, for example:</p>
  
  <pre><code>&lt;ScrollView&gt; 
      &lt;Component1&gt;
      &lt;Component2&gt;
      &lt;Component3&gt;
      &lt;Component4&gt;
      ...
  &lt;/ScrollView&gt;
  </code></pre>
  
  <p>Inside ScrollView I have some components, each of them can be anything like LinearLayout, RelativeLayout, TableRow, ...
  Now what I want is I will scroll the view, when the <code>&lt;Component2&gt;</code> reach the top of the screen, it will be keep on the screen and <code>&lt;Component3&gt;</code>, <code>&lt;Component4&gt;</code>... will keep scrolling till the end of page. When I scroll down, <code>&lt;Component2&gt;</code> will only be scrolled when all the <code>&lt;Component3&gt;</code> has became visible. I saw this on an Iphone app and wondered how to achieve this on Android.</p>
  
  <p>I don't know if I describe clearly enough but it is same like this video</p>
  
  <p><a href="http://www.youtube.com/watch?v=jXCrM1rzLZY&amp;feature=player_detailpage#t=71s" rel="noreferrer">http://www.youtube.com/watch?v=jXCrM1rzLZY&amp;feature=player_detailpage#t=71s</a></p>
  
  <p>When the tabs scrolled up to top, it stay there. And when scrolled down like in <code>1:36</code> of that video, it stay there until all the content below has became visible on the screen.</p>
  
  <p>Does anybody know how to do this on Android?</p>