android - 从listview android中删除了错误的行

Question

我知道有很多 Stack Overflow 问题针对我的问题得到了解决。我尝试了大部分解决方案，但没有一个对我成功。

我正在尝试实现 ListView 的列表行删除。长按列表行警报将弹出，其中有两个选项删除和取消。当按下删除时，将在自定义适配器中删除该行以及使用 mysql 表中的行异步任务。但只有最后一行被删除。

我已将 notifyDataSetChanged() 设置到我的适配器。即便如此，它也无法正常工作。

这是我的代码:

     listView.setOnItemLongClickListener(new OnItemLongClickListener() {

        @Override
        public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
                int position, long arg3) {
            System.out.println("postition value::" + position);
            removeItemFromList(position);

            return true;
        }
    });


    protected void removeItemFromList(int position) {
    final int deletePosition = position;
    System.out.println("deleting postition::"+deletePosition);
    AlertDialog.Builder alert = new AlertDialog.Builder(getActivity());

    alert.setTitle("Delete");
    alert.setMessage("Do you want delete this item?");
    alert.setPositiveButton("YES", new OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            // TOD O Auto-generated method stub

            // main code on after clicking yes
            new removefromfav().execute();
            courselist.remove(deletePosition);
        //  dataAdapter.remove(dataAdapter.getItem(deletePosition));
            dataAdapter.notifyDataSetChanged();
            listView.setAdapter(dataAdapter);
        //  dataAdapter.notifyDataSetInvalidated();

        }
    });
    alert.setNegativeButton("CANCEL", new OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            // TODO Auto-generated method stub
            dialog.dismiss();
        }
    });

    alert.show();

}

我的适配器类，

   private class MyCustomAdapter extends ArrayAdapter<Course> {

    private ArrayList<Course> countryList;

    public MyCustomAdapter(Context context, int textViewResourceId,
            ArrayList<Course> countryList) {
        super(context, textViewResourceId, countryList);
        this.countryList = new ArrayList<Course>();
        this.countryList.addAll(countryList);
    }

    private class ViewHolder {
        TextView code;
        TextView name;
        ImageView cover;
        TextView cost;
        ImageView ratingshow;
        ImageView promoimage;
        TextView enroll;
    }

    public void add(Course country) {

        this.countryList.add(country);
    }

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

        ViewHolder holder = null;

        if (convertView == null) {

            LayoutInflater vi = (LayoutInflater) getActivity()
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = vi.inflate(R.layout.course_overview, null);

            holder = new ViewHolder();
            holder.code = (TextView) convertView
                    .findViewById(R.id.coursename);
            holder.name = (TextView) convertView.findViewById(R.id.author);
            holder.cost = (TextView) convertView.findViewById(R.id.cost);
            holder.cover = (ImageView) convertView.findViewById(R.id.cover);
            holder.ratingshow = (ImageView) convertView
                    .findViewById(R.id.ratingimage);
            holder.promoimage = (ImageView) convertView
                    .findViewById(R.id.promoimage);
            holder.enroll = (TextView) convertView
                    .findViewById(R.id.enroll);
            convertView.setTag(holder);

        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        Course country = this.countryList.get(position);
        holder.code.setText(country.getCode());
        holder.name.setText(country.getName());
        holder.cost.setText("$ " + country.getRegion());
        holder.cover.setImageBitmap(country.getBitmap());




        return convertView;

    }

}

谁能帮帮我？？？

Answer 1

您没有从 MyCustomAdapter 中的 countryList 中删除任何内容。我看到一个功能，您可以在其中添加内容，但我没有看到一个删除内容的功能。

添加一个函数以从您的 countryList 中删除项目:

private class MyCustomAdapter extends ArrayAdapter<Course> {

private ArrayList<Course> countryList;

public MyCustomAdapter(Context context, int textViewResourceId,
        ArrayList<Course> countryList) {
    super(context, textViewResourceId, countryList);
    this.countryList = new ArrayList<Course>();
    this.countryList.addAll(countryList);
}

private class ViewHolder {
    TextView code;
    TextView name;
    ImageView cover;
    TextView cost;
    ImageView ratingshow;
    ImageView promoimage;
    TextView enroll;
}

public void add(Course country) {

    this.countryList.add(country);
}

//ADD THIS FUNCTION
public void remove(int index) {
    this.countryList.remove(index)
}

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

    ViewHolder holder = null;

    if (convertView == null) {

        LayoutInflater vi = (LayoutInflater) getActivity()
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = vi.inflate(R.layout.course_overview, null);

        holder = new ViewHolder();
        holder.code = (TextView) convertView
                .findViewById(R.id.coursename);
        holder.name = (TextView) convertView.findViewById(R.id.author);
        holder.cost = (TextView) convertView.findViewById(R.id.cost);
        holder.cover = (ImageView) convertView.findViewById(R.id.cover);
        holder.ratingshow = (ImageView) convertView
                .findViewById(R.id.ratingimage);
        holder.promoimage = (ImageView) convertView
                .findViewById(R.id.promoimage);
        holder.enroll = (TextView) convertView
                .findViewById(R.id.enroll);
        convertView.setTag(holder);

    } else {
        holder = (ViewHolder) convertView.getTag();
    }

    Course country = this.countryList.get(position);
    holder.code.setText(country.getCode());
    holder.name.setText(country.getName());
    holder.cost.setText("$ " + country.getRegion());
    holder.cover.setImageBitmap(country.getBitmap());




    return convertView;

}
}

然后在对话框的 onClick 回调中调用它

public void onClick(DialogInterface dialog, int which) {
        // TOD O Auto-generated method stub

        // main code on after clicking yes
        new removefromfav().execute();
        dataAdapter.remove(which);
        dataAdapter.notifyDataSetChanged();

    }