SampleViewModel.java

public class SampleViewModel {
    private String buttonTitle = "Click me!";
    private Context context;

    public SampleViewModel(Context context) {
        this.context = context;
    }

    public String getButtonTitle() {
        return buttonTitle;
    }

    public void onClick(View v) {
        Toast.makeText(this.context, "Hello", Toast.LENGTH_LONG).show();
    }
}