title: how to fix type '_CompactLinkedHashSet<String>' is not a subtype of type 'Map<String, dynamic>' error
body: <p>I am trying to use a <code>gestureDetector</code> on <strong>Text</strong>, so I can change between home widgets, using <code>onGenerateRoute</code> parameter of <code>MaterialApp</code> Widget. </p>
  
  <p><strong>gestureDetector over Text</strong>:</p>
  
  <p><a href="https://i.stack.imgur.com/534Wd.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/534Wd.png" alt="gestureDetector over Text"></a></p>
  
  <p><strong>onGenerateRoute (Screenshot 1)</strong>:</p>
  
  <p><a href="https://i.stack.imgur.com/dYGoF.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dYGoF.png" alt="onGenerateRoute"></a></p>
  
  <p><strong>onGenerateRoute (Screenshot 2)</strong>:</p>
  
  <p><a href="https://i.stack.imgur.com/oQZMX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oQZMX.png" alt="...continue"></a></p>