if (Platform.OS === 'android') {
this.listener = BackHandler.addEventListener('hardwareBackPress', this.onBackAndroid);
}
}
componentWillUnmount() {
if (Platform.OS === 'android') {
this.listener.remove('hardwareBackPress');
}
}
onBackAndroid = () => {
const navigator = this.refs.navigator;//**************************
const routers = navigator.getCurrentRoutes();
console.log('當前路由長度:' + routers.length);
if (routers.length > 2) {
navigator.pop();
return true;//接管默認行爲
} else {
//到了主頁了
if (this.lastBackPressed && this.lastBackPressed + 2000 >= Date.now()) {
//最近2秒內按過back鍵,可以退出應用。
return false;
}
this.lastBackPressed = Date.now();
ToastAndroid.show('再按一次退出應用', ToastAndroid.SHORT);
return true;
}
// return false;//默認行爲
};
備註:但是WebView需要特殊處理cangoback,也可以在WebView單獨註冊一個BackHandler!