Flutter 显示和隐藏 AlertDialog 取决于动态值

Question

在这个 sn-p 事件中，值是可以动态变化的流值。

LocationPermissions().serviceStatus.listen((event) {
    if(event == ServiceStatus.disabled){
      print('Location Disabled');
      testAlert(context); // Show dialog
    }else{
      testAlert(context); //I want hide dialog when user enable location.How do?
      print('Location Enabled');
         }
}   

这是我的对话代码。

void testAlert(BuildContext context){
  showDialog(
    context: context,
    builder: (BuildContext context) {
      // return object of type Dialog
      return AlertDialog(
        title: new Text("Location service disable"),
        content: new Text("You must enable your location access"),
        actions: <Widget>[
          // usually buttons at the bottom of the dialog
          new FlatButton(
            child: new Text("Go Setting"),
            onPressed: () {
              openLocationSetting();
              //visible ?Navigator.pop(context , true): Navigator.pop(context, false);

            },
          ),
        ],
      );
    },
  );
}

如何显示和隐藏取决于事件值。谢谢。

Answer 1

当用户启用location 时，不要调用对话框方法，只需删除此行testAlert(context);

LocationPermissions().serviceStatus.listen((event) {
    if(event == ServiceStatus.disabled){
      print('Location Disabled');
      testAlert(context); // Show dialog
    }else{
     // testAlert(context); //remove or just comment this line 
      print('Location Enabled');
         }

}

更新：-

通过在此调用 Navigator.pop() 来关闭平面按钮上的警报 对话框将被关闭

示例：-

void testAlert(BuildContext context){
  showDialog(
    context: context,
    builder: (BuildContext context) {
      // return object of type Dialog
      return AlertDialog(
        title: new Text("Location service disable"),
        content: new Text("You must enable your location access"),
        actions: <Widget>[
          // usually buttons at the bottom of the dialog
          new FlatButton(
            child: new Text("Go Setting"),
            onPressed: () {
              Navigator.pop(context)
              openLocationSetting();
              

            },
          ),
        ],
      );
    },
  );
}

当用户再次返回应用程序时，在生命周期中调用此方法，即 didChangeAppLifecycleState() 方法

@override
void didChangeAppLifecycleState(AppLifecycleState state) {
  // If user resumed to this app, check permission
  if(state == AppLifecycleState.resumed) {
   LocationPermissions().serviceStatus.listen((event) {
    if(event == ServiceStatus.disabled){
      print('Location Disabled');
      testAlert(context); // Show dialog
    }else{
      testAlert(context); //I want hide dialog when user enable location.How do?
      print('Location Enabled');
         }
    }  
  }
}