Question

Say for example I have a textview in class A,
and I want to change background color of textview from class B through a method…
how can I do it?

Answer 1

Make sure the tvView being passed is associated with a valid control (ie, findViewById() has been called before calling this function)

class B
{
public void changeBG(TextView tvView)
{
        tvView.setBackgroundColor(Color.BLUE);

}
};