CODE EXAMPLE FOR JAVA

android dialogfragment fullscreen stack overflow

This below answer works for me in fragment dialog.  


  Dialog dialog = getDialog();
        if (dialog != null)
        {
            int width = ViewGroup.LayoutParams.MATCH_PARENT;
            int height = ViewGroup.LayoutParams.MATCH_PARENT;
            dialog.getWindow().setLayout(width, height);
        }