2

这是我最近遇到的一个问题:我有一个带有自定义适配器类的列表视图,适配器接收一个列表视图并用其中的元素填充列表视图。现在,我想在列表视图的每一行上都有一个按钮来从中删除项目。我应该如何解决这个问题?有没有办法远程触发activity类中的某个方法,调用适配器上的notifydatachanged()方法来刷新listview?

4

2 回答 2

1

我做过这样的事情:

public class MyAdapter extends Adapter {

private final ArrayList<String> items = new ArrayList<String>();

// ...

deleteRow(int position) {
    items.remove(position);
    notifyDataSetChanged();
}
//

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

    if(convertView == null) {
        Tag tag = new Tag();
        // inflate as usual, store references to widgets in the tag
        tag.button.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
                    deleteRow(position);
        }
    });
    }
    // don't forget to set the actual position for each row
    Tag tag = (Tag)convertView.getTag();
    // ...
    tag.position = position;
    // ...
}



class Tag {

    int position;

    TextView text1;
    // ...
    Button button;
}

}
于 2010-04-29T18:40:17.977 回答
0

在getView()方法中,不能只在按钮上setOnClickListener()吗?

像这样的东西:

static final class MyAdapter extends BaseAdapter {

    /** override other methods here */

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        ViewHolder holder;

        if (convertView == null) {
            // inflate the view for row from xml file

            // keep a reference to each widget on the row.
            // here I only care about the button
            holder = new ViewHolder();
            holder.mButton = (Button)convertView.findViewById(R.id.button);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder)convertView.getTag();
        }

        // redefine the action for the button corresponding to the row
        holder.mButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // do something depending on position
                performSomeAction(position);
                // mark data as changed
                MyAdapter.this.notifyDatasetChanged();
            }
        }
    }
    static final class ViewHolder {
        // references to widgets
        Button mButton;
    }
}

如果您不确定是否要扩展 BaseAdapter,请查看 ApiDemos 中的示例 List14。这种技术为您提供了一种灵活的方式来修改适配器的几乎任何方面,尽管它是相当多的工作。

于 2010-04-29T16:55:22.100 回答