How do i make a TabNavigator button push a modal screen with React Navigation

Question

Using the React Navigation tab navigator https://reactnavigation.org/docs/navigators/tab how do I make one of the tab buttons push the screen up as a full screen modal? I see the stack navigator has a mode=modal option. how do I get that mode to be used when clicking on the TakePhoto tab button? Clicking on it currently still shows the tab bar on the bottom.

const MyApp = TabNavigator({
  Home: {
    screen: MyHomeScreen,
  },
  TakePhoto: {
    screen: PhotoPickerScreen, // how can I have this screen show up as a full screen modal?
  },
});

Answer 1

Actually, there is no support in react-navigation to change the way of presentation on the fly from default to modal (see the discussion about this here). I ran into the same issue and solved it by using a very top StackNavigator with headerMode set to none and mode set to modal:

const MainTabNavigator = TabNavigator(
    {
        Tab1Home: { screen: Tab1Screen },
        Tab2Home: { screen: Tab2Screen }
    }
);

const LoginRegisterStackNavigator = StackNavigator({
    Login: { screen: LoginScreen }
});

const ModalStackNavigator = StackNavigator({
    MainTabNavigator:          { screen: MainTabNavigator            },
    LoginScreenStackNavigator: { screen: LoginRegisterStackNavigator }
}, {
    headerMode: 'none',
    mode:       'modal'
});

This allows me to do the following (using redux) in Tab1Screen and Tab2Screen to bring up the modal view from wherever I want:

this.props.navigation.navigate('LoginScreenStackNavigator');

Answer 2

Not sure if this is still relevant for you, but i've managed to find away to achieve this.

So i've managed to get it working by using the tabBarComponent inside the tabNavigatorConifg, you can stop the tab navigation from navigating depending on the index.

   tabBarComponent: ({jumpToIndex, ...props, navigation}) => (
        <TabBarBottom
            {...props}
            jumpToIndex={index => {
                if (index === 2) {
                    navigation.navigate('camera')
                }
                else {
                    jumpToIndex(index)
                }
            }}
        />

    )

Once you've done this, my method of showing the view modally on top of the tab views was to put the tabnavigator inside of a stacknavigatior and then just navigate to a new screen inside of the stacknavigator.

Answer 3

react-navigation's bottomTabNavigator has a tabBarOnPress navigation option you can use to override tab presses:

https://reactnavigation.org/docs/en/bottom-tab-navigator.html#tabbaronpress

const AppContainer = createStackNavigator(
  {
    default: createBottomTabNavigator(
      {
        TAB_0: Stack0,
        TAB_1: Stack1,
        TAB_2: Stack2,
        TAB_3: View // plain rn-view, or any old unused screen
      },
      {
        defaultNavigationOptions: {
          // other tab navigation options...
          tabBarOnPress: ({ navigation, defaultHandler }) => {
            if (navigation.state.key === 'TAB_3') {
              navigation.navigate('tabToOpenAsModal');
            } else {
              defaultHandler();
            }
          }
        }
      }
    ),
    tabToOpenAsModal: {
      screen: TabToOpenAsModalScreen
    }
  },
  {
    mode: 'modal',
    headerMode: 'none'
  }
);

If you nest your tab navigator within a stack navigator with a modal, you can open this when the tab bar button is pressed. Since the modal was opened and not the tab, when the modal is closed the app returns to the screen that was visible before the modal tab was pressed.