public void setFocus(View focus) {
assert (focus != null);
clearFocus();
mFocus = focus;
moveToTopOfPile(focus);
setHighlight(focus, true);
scheduleFocusReaper(mMaxFocusTime);
}
public void clearFocus() {
if (hasFocus()) {
setHighlight(getFocus(), false);
}
mFocus = null;
}