压倒一切的Adapter.getViewAdapter、getView

2023-09-06 02:43:53 作者:╬═ 掵中紸顁

我是新来的Andr​​oid编程和做带适配器的第一个步骤(对于的ListView )。

I'm new to android programming and doing the first steps with Adapters (for a ListView).

重写 Adapter.getView 我经常看到这样的事情:

Overriding the Adapter.getView I often see things like this:

public View getView(int position, View convertView, ViewGroup parent) {

    View itemView = null;

    if (convertView == null) {
        LayoutInflater inflater = (LayoutInflater) parent.getContext()
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        itemView = inflater.inflate(R.layout.table_row, null);
    } else {
        itemView = convertView;
    }

    // play with itemView

    return itemView;
}

我的问题是说反对这样的:

My question is what speaks against this:

public View getView(int position, View convertView, ViewGroup parent) {

    View itemView = super(position, convertView, parent);

    // play with itemView

    return itemView;
}

这似乎为我工作,但我敢肯定有一个大点我错过:D

This seems to work for me but I'm sure there's a big point I'm missing :D

感谢您的阅读,对不起我的英文不好...

Thanks for reading and sorry for my bad english ...

推荐答案

您可以使用

View itemView = super(position, convertView, parent);

如果只有你是从派生准备使用适配器(未 BaseAdapter ),如 SimpleAdapter ArrayAdapter ,因为它们的已的有他们实施的 getView()

if only you are deriving from "ready to use" adapters (not BaseAdapter), like SimpleAdapter, or ArrayAdapter, as they already have their implementation for the getView().

看一看他们:http://grep$c$c.com/file/repository.grep$c$c.com/java/ext/com.google.android/android/4.0.4_r2.1/android/widget/ArrayAdapter.java#361对于一个ArrayAdapter,并 http://grep$c$c.com/file/repository.grep$c$c.com/java/ext/com.google.android/android/4.0.4_r2.1/android/widget/SimpleAdapter.java#113为SimpleAdapter。

Have a look at them: http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.0.4_r2.1/android/widget/ArrayAdapter.java#361 for the ArrayAdapter, and http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.0.4_r2.1/android/widget/SimpleAdapter.java#113 for SimpleAdapter.

如果您在 BaseAdapter 导出,你必须manualy实现整个方法,如你在第一个例子中所描述的,因为它没有出来的盒子:http://grep$c$c.com/file/repository.grep$c$c.com/java/ext/com.google.android/android/4.0.4_r2.1/android/widget/BaseAdapter.java#BaseAdapter

If you derive from BaseAdapter, you will have to manualy implement the whole method, as you've described in the first example, because it does not have it out of the box: http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.0.4_r2.1/android/widget/BaseAdapter.java#BaseAdapter