AndroidX: [Material] Slider.addOnChangeListener binding missing

Version Information

Visual Studio version (eg. 16.8 or 8.8): 16.8.3
Xamarin.Android version (eg. 11.1): 11.1
Using AndroidX or Support Libraries: Xamarin.Google.Android.Material 1.2.1.1

Describe your Issue:

Slider.IOnChangeListener is bound, but there is no way to add it to the Slider class, the addOnChangeListener method hasn’t been bound

Steps to Reproduce (with link to sample solution if possible):

var slider = FindViewById<Google.Android.Material.Slider>(Resource.Id.my_slider);
slider.addOnChangeListener(listener); // compile error
slider.Change += Slider_Changed; // compile error

About this issue

Original URL
State: open
Created 4 years ago
Reactions: 6
Comments: 17 (4 by maintainers)

Most upvoted comments

This is a workaround until they fix binding issue:

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState, Resource.Layout.my_activity);
    slider = FindViewById<Slider>(Resource.Id.slider);
    slider.Touch += Slider_Touch;
}

private void Slider_Touch(object sender, View.TouchEventArgs e)
{
    switch (e.Event.Action)
    {
        case MotionEventActions.Move:
        case MotionEventActions.Up:
            OnValueChange(slider, slider.Value, true);  //(Slider slider, float value, boolean fromUser)
            break;
    }
    e.Handled = false;
}

//This footprint matches native library callback
private void OnValueChange(Java.Lang.Object sender, float value, bool fromUser)
{
    //Do what you want to do as if you are listening to ValueChanged event (or at least very near to actual event)
}

ibrahimmd90 on Aug 2, 2021

Sadly, this issue is still present with 1.4.0

tipa on Jul 13, 2021

workaround:

var method = Class.ForName("com.google.android.material.slider.BaseSlider").GetDeclaredMethods().FirstOrDefault(x => x.Name == "addOnChangeListener");
method?.Invoke(slider, this); // this is implementing IBaseOnChangeListener

tipa on Feb 5, 2021

Still same with “1.8.0” version. Any progress ? <PackageReference Include="Xamarin.Google.Android.Material" Version="1.8.0" />

letscodewithkalyan on Mar 7, 2023