title: staggered grid view in flutter
body: <p>I am making a grid like instagram where every seventh element is of 2X1. The problem is i want to show a different widget at seventh index but my code splits the gridTile widget rather than showing a different widget.</p>
  <p><strong>CODE:-</strong></p>
  <pre><code>return StaggeredGridView.countBuilder(
      shrinkWrap: true,
      crossAxisCount: 3,
      itemCount: gridTile.length,
      itemBuilder: (context,index)=&gt;gridTile[index],
      staggeredTileBuilder: (index)=&gt;StaggeredTile.count(
        1,(index%7==0)?2:1,
      ),
    );
  </code></pre>