android ListView的item与其子控件的焦点问题

当item有焦点时，item上的button等子控件获取不到焦点；

当子控件有焦点时，item无焦点无法响应onItemClick事件

ViewGroup.FOCUS_AFTER_DESCENDANTS：表示item的子控件优先于item获得焦点；

ViewGroup.FOCUS_BEFORE_DESCENDANTS：表示item优先于其子控件获得焦点。

解决办法：

listView.setOnItemSelectedListener(onItemSelectedListener);
private AdapterView.OnItemSelectedListener  onItemSelectedListener = 
	new AdapterView.OnItemSelectedListener(){
	@Override
	public void onItemSelected(AdapterView<?> parent, View view,
			int position, long id) {
		//当此选中的item的子控件需要获得焦点时
		parent.setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
		//else parent.setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
	}
	
	@Override
	public void onNothingSelected(AdapterView<?> parent) {
		parent.setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
	}
}