How to retrieve the message sent via MainActivity on the App.css page?-CodePudding

in MainActivity.cs I send the following message:

resultIntent.PutExtra("message", "string123");

then in App.css i am trying to accept the message as follows:

Intent.Extras.GetString("message", "");

but the path I'm using is for MainActivity.cs...

CodePudding user response：

It seems like you want to pass a message from MainActivity to App when the App constructor is first created. This you can achieve in a number of ways

Option 1 (Recommended)

Simply by giving a parameter to App constructor as follows

public App(string message)
{
  InitializeComponent();

  MainPage = new AppShell(message);
}

This you can set from MainActivity on creation as follows

protected override void OnCreate(Bundle savedInstanceState)
{
  base.OnCreate(savedInstanceState);

  Xamarin.Essentials.Platform.Init(this, savedInstanceState);
  global::Xamarin.Forms.Forms.Init(this, savedInstanceState);
  LoadApplication(new App("string123"));
}

Option 2

Yet another option, which i would not prefer, could be to pass an instance of MainActivity to App as follows

protected override void OnCreate(Bundle savedInstanceState)
{
  base.OnCreate(savedInstanceState);

  this.Intent.PutExtra("message", "string1234");

  Xamarin.Essentials.Platform.Init(this, savedInstanceState);
  global::Xamarin.Forms.Forms.Init(this, savedInstanceState);
  LoadApplication(new App(this));

}

then in App constructor you use this instance as follows

Android.App.Activity _mainActivity;

public App(object mainActivity)
{
  InitializeComponent();

  string message = "Void";

  if (Device.RuntimePlatform == Device.Android)
  {
    _mainActivity = (Android.App.Activity)mainActivity;
    message = _mainActivity.Intent.Extras.GetString("message", "");
  }

  MainPage = new AppShell(message);
}