title: How do I dim background when Modal is displayed in react-native
body: <p>I have got the modal as expected but I could not dim the background. </p>
  
  <p>I also tried <code>backdropColor = {'green'}</code>  <code>backdropOpacity = {1}</code> but still the background exists.
  I need help for this. Below is my code:</p>
  
  <pre><code>import Modal from "react-native-modal";
      &lt;View 
            style={styles.MainContainer}&gt;
              &lt;Modal
                  backdropColor={'green'}
                  backdropOpacity= {1}
                  animationType={"slide"}
                  visible={this.state.ModalVisibleStatus}
                  onRequestClose={ ()=&gt;{ this.ShowModalFunction(!this.state.ModalVisibleStatus)}}&gt;
  
                &lt;View style={{ flex:1, justifyContent: 'center', alignItems: 'center' }}&gt;
                  &lt;View style={styles.ModalInsideView}&gt;
                    &lt;Text 
                        style={styles.TextStyle}&gt;
                        Enter the Number of Tickets to be Printed. 
                     &lt;/Text&gt;
  
                      &lt;NumberSpinner
                      packageCount={this.state.tickets} min={0} max={20}
                      onChange={this.ticketsCount}
                    /&gt;
  
                   &lt;Button  
                        title="Print Tickets" 
                         onPress={() =&gt; { this.ShowModalFunction(!this.state.ModalVisibleStatus)}}/&gt;
                &lt;/View&gt;
              &lt;/View&gt;
            &lt;/Modal&gt;
  </code></pre>