javascript - 如何在 native react 中切换抽屉导航器？

Question

我正在使用抽屉式导航。当我单击汉堡菜单图标时，抽屉导航的抽屉不起作用，我无法切换抽屉。代码 1 不起作用，但代码 2 起作用，任何人都可以帮我找出原因吗？

代码:

    Burger menu icon code 1:

    // Inside Header
    navigationOptions: ({ navigation }) => ({
                // headerTitle: 'Rchampz',
                headerLeft:
                <TouchableOpacity  onPress={() => {navigation.dispatch(DrawerActions.toggleDrawer())} }>
                    <MenuImage navigation={navigation}/>
                </TouchableOpacity>,

//Created component and added inside navigationOptions

    const MenuImage = ({navigation}) => {
        if(!navigation.state.isDrawerOpen){
            return <TouchableOpacity><Image source={require('../assets/images/menu.png')} style={{width: 24, height: 24, resizeMode: 'contain' ,marginLeft: 15}}/></TouchableOpacity>
        }else{
            return <MenuIcon style={{paddingLeft: 10, paddingRight: 10}} name="md-arrow-back" size={30} color="black"/>
        }
    }

    Burger menu icon code 2:

    //Inside header

    navigationOptions: ({ navigation }) => ({
                // headerTitle: 'Rchampz',
                headerLeft:
                <TouchableOpacity  onPress={() => {navigation.dispatch(DrawerActions.toggleDrawer())} }>
                    <MenuImage navigation={navigation}/>
                </TouchableOpacity>,


//Created component and added inside navigationOptions

    const MenuImage = ({navigation}) => {
        if(!navigation.state.isDrawerOpen){
            return <MenuIcon style={{paddingLeft: 10, paddingRight: 10}} name="md-menu" size={30} color="black"/>
        }else{
            return <MenuIcon style={{paddingLeft: 10, paddingRight: 10}} name="md-arrow-back" size={30} color="black"/>
        }
    }

Answer 1

因为您在第一个菜单图像中设置菜单图像的方式。您将图像包装在另一个 TouchableOpacity 中，这意味着内部 TouchableOpacity 正在拾取用户触摸事件。这实际上不是您想要的行为，因为您希望 headerLeft 上的 TouchableOpacity 成为输入的接收器。因此，只需删除“额外的”TouchableOpacity即可。

// Inside Header
navigationOptions: ({ navigation }) => ({
    headerLeft:
    <TouchableOpacity onPress={() => {navigation.dispatch(DrawerActions.toggleDrawer())} }>
        <MenuImage navigation={navigation}/>
    </TouchableOpacity>,

//Created component and added inside navigationOptions
const MenuImage = ({navigation}) => {
    if(!navigation.state.isDrawerOpen){
        // No need of Touchable here. Since you want the above Touchable to pick up the onPress event.
        return <Image source={require('../assets/images/menu.png')} style={{width: 24, height: 24, resizeMode: 'contain' ,marginLeft: 15}}/>. 
    }else{
        return <MenuIcon style={{paddingLeft: 10, paddingRight: 10}} name="md-arrow-back" size={30} color="black"/>
    }
}

第二个示例有效的原因很简单，没有额外的 Touchable 处理 onPress 事件。