margin and background color for Button

Margin in Java

            Button button=(Button)findViewById(R.id.button);
            Button button2=(Button)findViewById(R.id.button2);
            button.setBackgroundColor(getResources().getColor(R.color.grey_100));
            button2.setBackgroundColor(getResources().getColor(R.color.grey_100));


            ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) button.getLayoutParams();
            params.leftMargin=7;
            params.rightMargin=7;


            ViewGroup.MarginLayoutParams params2 = (ViewGroup.MarginLayoutParams) button2.getLayoutParams();
            params2.leftMargin=7;
            params2.rightMargin=7;