我曾尝试阅读大量的文章,但我仍然无法理解。我的具体问题是:
I have tried reading numerous articles but I still can't understand. My specific questions are:
什么是完全LayoutInflater?的功能 为什么所有的,我读过检查convertview为空或不首先的文章?这是什么意思,当它为空,什么意思时,是不是? 什么是家长parameted,这种方法接受?为寻找谢谢了!
1:LayoutInflater需要你的布局XML的文件,并从它的内容创建不同的视图对象。
1: The LayoutInflater
takes your layout XML-files and creates different View-objects from its contents.
2:适配器在建造时,重复使用次数,当查看滚动,这样不再可见,它可以被用于显示新的景色之一。这种重复使用View是 convertView
。如果这是null,则意味着没有回收的查看,我们必须建立一个新的,否则我们应该用它来避免建立新的。
2: The adapters are built to reuse Views, when a View is scrolled so that is no longer visible, it can be used for one of the new Views appearing. This reused View is the convertView
. If this is null it means that there is no recycled View and we have to create a new one, otherwise we should use it to avoid creating a new.
3:在父
提供这样你就可以吹你的看法到,对于合理布置参数
3: The parent
is provided so you can inflate your view into that for proper layout parameters.
所有这些结合在一起,可以用来有效地创建将出现在您的列表(即需要一个适配器或其他视图)的观点:
All these together can be used to effectively create the view that will appear in your list (or other view that takes an adapter):
public View getView (int position, View convertView, ViewGroup parent){
if( convertView == null ){
//We must create a View:
convertView = inflater.inflate(R.layout.my_list_item, parent, false);
}
//Here we can do changes to the convertView, such as set a text on a TextView
//or an image on an ImageView.
return convertView;
}
注意使用 LayoutInflater
,即父
可以被用作论据,以及如何 convertView
被重复使用。
Notice the use of the LayoutInflater
, that parent
can be used as an argument for it, and how convertView
is reused.