How do I handle results from Control.EvaluateJavascript in xamarin?

Question

I know how to call js-functions with the Android.Webkit as long as I dont have to handle a return-value:

 Control.EvaluateJavascript("removeAllPins()", null);

But I dont know how to call a function that returns a function? The function takes an object of IValueCallback as a paramter but I can't create an instance of it because it's an interface and not a class.
How do I get the result of a js-function thats called in Android with EvaluateJavascript?

Leo Zhu · Accepted Answer · 2020-08-10T06:36:28.310

2

You could do in your webview renderer like below ,refer to this:

Control.EvaluateJavascript("javascript: removeAllPins();", new EvaluateBack());

class EvaluateBack : Java.Lang.Object,IValueCallback
  {

      public void OnReceiveValue(Object value)
      {

        Toast.MakeText(Android.App.Application.Context, value.ToString(), ToastLength.Short).Show();// you will get the value you want to return.
      }
   }

edited Aug 10 '20 at 06:36

answered Aug 10 '20 at 06:22

Leo Zhu

15,726
1
7
23

Makes perfect sense, thanks, but why does this return the value 100? – actopozipc Aug 10 '20 at 06:35
@actopozipc my mistake,this is in my project. – Leo Zhu Aug 10 '20 at 06:36

score 0 · Answer 2 · answered Aug 12 '20 at 23:11

0

maybe:

Control.EvaluateJavascript("removeAllPins()", null, new gitGud());

answered Aug 12 '20 at 23:11

alobre

85
7

Mind to explain why this would help? – BDL Aug 13 '20 at 11:31

How do I handle results from Control.EvaluateJavascript in xamarin?

2 Answers2