title: how to change background of a touchableOpacity in iteration
body: <p>I am looping an array , wrapping each item into touchableOpacity  ,  attempting to change background Color of the clicked item on onPress event,
  my issue is that its changing the background color of the whole items   , is there a way to change background Color to only the clicked item , here is my code </p>
  
  <pre><code> return this.props.categes.map( (
  
              cat,i)=&gt;
  
              &lt;TouchableOpacity onPress = {() =&gt; this.changeBackground(i)} key = {i} style={{alignSelf : 'center', paddingLeft: 5, paddingRight : 7, paddingTop : 5, paddingBottom : 5, backgroundColor : this.state.background}}&gt;
              &lt;Text style={{color : '#838D8D'}}&gt; {cat.name}&lt;/Text&gt;
              &lt;/TouchableOpacity&gt;
  
              )
  
    changeBackground(item){
  
          if(item)
          {
              this.setState({
                  background: 'red'
              })
          }
      }
  </code></pre>