Make all OnChange function virtual you can overide this functions.

[teunlielu]

Is your feature request related to a problem? Please describe.
In the current setup you now program the following:
simple example:
public override string Value { get => base.Value; set { if (value is null) { ChangeEventArgs args = new ChangeEventArgs(); args.Value =""; OnChange(args); // Directly to base.Value you will lose communication with your binding. } else { base.Value = value; } } }

Describe the solution you'd like
Make all OnChange function virtual you can overide this functions.
protected override async Task OnChange(ChangeEventArgs args) { if(args.Value is null) { args.Value = ""; } await base.OnChange(args); }