Is there an onPress for TabNavigator tab in react-

问题:

I am trying to have a DrawerNavigator when user taps on the last tab(for example 'More') in TabNavigator.

How is this possible to achieve it without having a screen for that tab and then calling the DrawerNavigator in componentWillMount.

componentWillMount() {
   this.props.navigation.navigate("DrawerOpen") 
}

It is kind of a hack which is not proper solution I think(This way 'More' screen is loaded), there has to be a better solution for that.

回答1:

This is also a bit of hack but I think its the simplest hack without using a custom TabBar or redux.

What you can do is to create a screen component rendering null

export default class More extends Component {
  render() {
    return null;
  }
}

Then add this screen to your TabNavigator, import TabBars from react-navigation and toggle drawer for certain index.

import { TabBarBottom, TabBarTop } from 'react-navigation';

const TabBar = Platform.OS === 'ios' ? TabBarBottom : TabBarTop;

const Navigator = TabNavigator({
  Tab1: { screen: Tab1 },
  Tab2: { screen: Tab2 },
  Tab3: { screen: Tab3 },
  More: { screen: More }
}, {
  tabBarComponent: ({jumpToIndex, ...props, navigation}) => (
        <TabBar
            {...props}
            jumpToIndex={index => {
                if (index === 3) {
                    navigation.navigate('DrawerToggle'); //Toggle drawer
                }
                else {
                    jumpToIndex(index)
                }
            }}
        />
    )
});

This way you simple continue using default TabBars from react-navigation, have an icon/label for your drawer and use it to toggle drawer.

回答2:

You need to implement custom tabBarComponent for TabNavigator. It's a normal component you provide in the options.

Then in the component, you just define onPress for the "More" button, which opens the drawer.

It's as simple as that.