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);
}
override fun onStart() {
super.onStart()
dialog?.let {
val width = ViewGroup.LayoutParams.MATCH_PARENT
val height = ViewGroup.LayoutParams.MATCH_PARENT
it.window?.setLayout(width, height)
}
}