How to access textview in MainPage.xaml from MainActivity.cs in visual studio 2017

Question

I have create xamarin cross-paltform. I have textviews in mainActivity.xanl that is shared to all other mobile system(ios,android,) that I need to call it from Mainpage in android. and is it possible to do it otherway around, by calling textview in mainactivity from mainpage

Answer 1

You could use Messaging Center to send notification from ContentPage to MainActivity.

in MainActivity

using Xamarin.Forms;

   protected override void OnCreate(Bundle savedInstanceState)
    {
        TabLayoutResource = Resource.Layout.Tabbar;
        ToolbarResource = Resource.Layout.Toolbar;

        base.OnCreate(savedInstanceState);

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


        MessagingCenter.Subscribe<Object>(this, "testview", (arg) => {

            TextView textView = FindViewById<TextView>(Resource.Id.xxx);

            //... do some thing you want
        
        });


        LoadApplication(new App());
    }

in ContentPage

invoke the line when you want

MessagingCenter.Send<Object>(this, "testview");