我有一个带有自定义适配器的listview,我需要访问这个listview的各个行的视图。我正在尝试使用getChildat()执行此操作,但它返回的是空值。
这是我的列表视图:
myListView = (ListView) findViewById (R.id.listViewLayout);
这是自定义适配器:
public class MyListAdapter extends BaseAdapter {
...
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_row_layout, parent, false);
}
...
}
我创建一个列表,并为listview设置它:
List <String> myList = new ArrayList<String>();
myList.add("entry 1");
myList.add("entry 2");
myList.add("entry 3");
MyListAdapter myListAdapter = new MyListAdapter(getApplicationContext(), myList);
myListView.setAdapter(myListAdapter);
现在,我想访问单个行的视图。
View v = myListView.getChildAt(myListView.getFirstVisiblePosition());
不管怎样,这个v都是空的。此外,
myListView.getChildCount()
始终返回空值。我错过了什么?是否需要将
convertView
添加到parent
中的getView()
?我是否向inflate
传递了错误的参数?我费了很大的劲才弄明白。请帮帮我!
编辑:我正在发布MyListAdapter类:
public class MyListAdapter extends BaseAdapter {
private Context context;
private List<String> myList;
public MyListAdapter(Context c, List<String> m) {
context = c;
myList = m;
}
@Override
public int getCount() {
return myList.size();
}
@Override
public Object getItem(int position) {
return myList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final int pos = position;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_row_layout, parent, false);
}
TextView text = (TextView) convertView.findViewById(R.id.itemText);
text.setText(myList.get(pos));
// Set the onClick Listener on this button
Button rowButton = (Button) convertView.findViewById(R.id.itemButton);
//commenting next two lines makes the list row clickable
rowButton.setFocusableInTouchMode(false);
rowButton.setFocusable(false);
rowButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Toast.makeText(context, myList.get(pos), Toast.LENGTH_SHORT).show();
}
});
convertView.setTag(pos);
return convertView;
}
}
最佳答案
很可能你在onCreate()
中做了所有这些。任何与视图相关的方法都将返回null(或空),因为列表尚未呈现。你需要孩子的视角做什么?