安卓自定义列表视图

Question

hello all我正在为员工显示任务的项目，这些任务需要由员工设置任务状态，我通过菜单处理以更新统计信息这是阵列适配器

public class MyArrayAdapter extends ArrayAdapter<Task> {
private static int viewCount = 0;
public MyArrayAdapter(Context context) {
    super(context, R.layout.listview_items, R.id.taskTitle);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    boolean created = false;
    if (convertView == null) {
        created = true;
        viewCount++;
    }
    View view = super.getView(position, convertView, parent);
    Task task = getItem(position);
    if (task != null) {
        TextView taskTitle = (TextView) view.findViewById(R.id.taskTitle);
        ImageView imageView = (ImageView) view.findViewById(R.id.taskImage);
        TextView taskStatus = (TextView) view.findViewById(R.id.taskStatus);
        TextView taskDate = (TextView) view.findViewById(R.id.taskDate);

        if (created && taskTitle != null) {
            taskTitle.setText(task.getTaskTitle());
        }
        if (imageView != null && task.image != null) {
            imageView.setImageDrawable(task.image);
        }
        if (taskStatus != null && task.taskStatus != null) {
            taskStatus.setText(task.getTaskStatus());
        }
        if (taskDate != null && task.taskDate != null) {
            taskDate.setText(task.getTaskDate());
        }
    }
    return view;
}

}

我需要更改文本视图"任务状态"，我尝试这样做

        View v = adapter
            .getView(listView.getSelectedItemPosition(),null , null);
    TextView textView = (TextView) v.findViewById(R.id.taskStatus);
    textView.setText("Started");
    adapter.notifyDataSetChanged();

但它不起作用，任何人都可以帮助我

Answer 1

您应该从代码中删除以下行：

View v = adapter.getView(listView.getSelectedItemPosition(),null , null);
TextView textView = (TextView) v.findViewById(R.id.taskStatus);
textView.setText("Started");

而是确定选定的Task实例：task 和

task.setTaskStatus("Started");
adapter.notifyDataSetChanged();

这样，您可以更改基础数据，并通过通知适配器有关此更改的信息，让适配器显示正确的视图（正确更新相应的TextView;这就是 notifyDataSetChanged 方法的作用。