title: React native, shoutem/ui : navigating back on NavigationBar does not work on iOS
body: <p>I am struggling to make back navigation arrow on shoutem/ui NavigationBar work on iOS. The navigation bar looks like this and works on Android as expected (tap on the arrow navigates to specific predefined view) :</p>
  
  <p><a href="https://i.stack.imgur.com/mTO82.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mTO82.png" alt="Navigation bar"></a></p>
  
  <p>The related layout is as follows :</p>
  
  <pre><code>import {
    Text,
    Button,
    View,
    Image,
    Divider,
    Spinner,
    NavigationBar,
    Caption
  } from '@shoutem/ui';
  
  
  render() {
    const {navigate} = this.props.navigation;
    if (this.state.submitted &amp;&amp; this.props.loading) {
      return (
        &lt;Spinner style={{
          flex: 1,
          justifyContent: 'center',
          alignItems: 'center'
        }} /&gt;
      );
    }
    return (
      &lt;Container style={{ flex: 1, backgroundColor: '#ffffff' }}&gt;
        &lt;Content&gt;
            &lt;NavigationBar
              styleName='no-border'
              hasHistory
              navigateBack={() =&gt; navigate('WelcomeScreen')}
          /&gt;
          &lt;Grid&gt;
            &lt;Row style={{ height: 100, justifyContent: 'center', alignItems: 'center', paddingTop: 100 }}&gt;
              &lt;Image
                style={{ width: 96, height: 89 }}
                source={require('../login-logo.png')}
                blurRadius={1} /&gt;
            &lt;/Row&gt;              
            //some other rows and columns
          &lt;/Grid&gt;
        &lt;/Content&gt;
      &lt;/Container&gt;
      );
     }
   }
  </code></pre>
  
  <p>On Android the following works as expected. On iOS (Xcode simulator) the  navbar is displayed correctly, however tapping on it does nothing. No log events nor errors are generated as well. I assume that the navbar can somehow be overlaid by some other element. However, the same problem exists with the other views with different elements inside the grid below the navbar. Does anyone have experience with this issue? What is the most likely cause and what am I doing wrong?</p>