안드로이드 activity 이동시 focus 문제

public static View preventInitialFocus(final Activity activity)
{
    final ViewGroup content = (ViewGroup)activity.findViewById(android.R.id.content);
    final View root = content.getChildAt(0);
    if (root == null) return null;
    final View focusDummy = new View(activity);
    final View.OnFocusChangeListener onFocusChangeListener = new View.OnFocusChangeListener()
    {
        @Override
        public void onFocusChange(View view, boolean b)
        {
            view.setOnFocusChangeListener(null);
            content.removeView(focusDummy);
        }
    };
    focusDummy.setFocusable(true);
    focusDummy.setFocusableInTouchMode(true);
    content.addView(focusDummy, 0, new LinearLayout.LayoutParams(0, 0));
    if (root instanceof ViewGroup)
    {
        final ViewGroup _root = (ViewGroup)root;
        for (int i = 1, children = _root.getChildCount(); i < children; i++)
        {
            final View child = _root.getChildAt(i);
            if (child.isFocusable() || child.isFocusableInTouchMode())
            {
                child.setOnFocusChangeListener(onFocusChangeListener);
                break;
            }
        }
    }
    else if (root.isFocusable() || root.isFocusableInTouchMode())
        root.setOnFocusChangeListener(onFocusChangeListener);

    return focusDummy;
}