title: component render one time when click tab on drawerNavigator in react native
body: <p>I'm new on react native getting issue on calling component. Whenever click on drawer navigator tab first time component render and API called But when back to the home page and again call that component API not called. I want to recall that function.</p>
  
  <p>Here is my drawer navigator code : </p>
  
  <pre><code>const AppDrawerNavigator = createDrawerNavigator({
    Home: {
      screen: Home,
      navigationOptions: {
        drawerLabel: 'Home',
        drawerIcon: () =&gt; (
          &lt;Icon name="home" size={20} color="#0f1f7b" /&gt;
          )
      },
    },
    PreviousInspection: {
      screen: PreviousInspection,
      navigationOptions: {
        drawerLabel: 'Previous Inspection',
        drawerIcon: () =&gt; (
          &lt;Icon name="file" size={20} color="#0f1f7b" /&gt;
          )
      },
    },
    Logout: {
      screen: Logout,
      navigationOptions: {
          drawerLabel: 'Logout',
          drawerIcon: () =&gt; (
            &lt;Icon name="sign-out" size={20} color="#0f1f7b" /&gt;
            )
      },
    }
  },
  {
    drawerBackgroundColor: "#fff",
    contentOptions: {
      activeTintColor: '#000',
      inactiveTintColor: '#000',
      activeBackgroundColor: '#bfc7f3',
      itemStyle: {
        fontSize: 12,
      },
    },
  });
  </code></pre>