title: Problems using RecyclerView with StaggeredLayoutManager
body: <p>I succesfully implemented RecyclerView using StaggeredLayoutManager with 2 col/spans. I have variable heighted items in each col, heights are not fixed.</p>
  
  <p>Problem is, when I scroll down and up in RecyclerView, sometimes a gap is occured at the top item of one of the rows. I added a video describing my problem.</p>
  
  <p>I simply added a StaggeredLayout with span value 2, and adapted my items with an adapter.</p>
  
  <p>+-+-+-+-+-+-+-+-+-+-+-+-+    &lt;------ Top of RecyclerView</p>
  
  <p>--------------                    &lt;- Top item in left column</p>
  
  <p>                   -------------  &lt;- Top item in right column, has unexpected  gap/offset/margin at top. 
  Gap sometimes occurs. Sometimes, everything is well aligned and no problems.</p>
  
  <p>Here is the video I take from my application. 
  <a href="https://youtu.be/gmB7h73YR3M" rel="nofollow">https://youtu.be/gmB7h73YR3M</a></p>
  
  <p>Look at the topmost 2 pictures(LinearLayouts) in the list, cup and monitor. Their top position differs after each scroll down and then up event, and an unwanted grey area (Backgroundcolor of RecyclerView) appears at there.</p>
  
  <p>Between 0-3 sec, there is a gap on top of cup, left column.</p>
  
  <p>Between 7-8, there is a gap but little than 0-3</p>
  
  <p>Between 10-12, everything is fine, their tops are at same level.</p>
  
  <p>Between 19-21, this time right column has a gap on top.</p>
  
  <p>Any reasons why I have this problem,  any solutions?</p>
  
  <p>EDIT:
  Because I don't want so much moving items, I set gapping strategy as GAP_HANDLING_NONE. However, when I set strategy as GAP_HANDLING_MOVE_ITEMS_BETWEEN_SPANS, toppest line of two items get aligned when Scrolling Up ends at top. My observation is, when scrolling to the elements at top, a last calculation is made to Align top lines of 2 items if strategy is GAP_HANDLING_MOVE_ITEMS_BETWEEN_SPANS, but not in GAP_HANDLING_NONE. I can see it is aligned with my eyes, but it doesn't seem to happen when strategy is GAP_HANDLING_NONE. </p>