在自定义光标适配器中滚动时更改 Listview 项目值

Question

我正在使用带有光标适配器的列表视图。当我单击此图像视图时，此列表视图在每个项目中都有一个图像视图，我更改了正在正确更改的图像视图图像，但是当我滚动列表图像视图时，它会更改为其原始视图。 注意：我正在使用光标适配器。（我知道列表视图回收并且我知道控制简单适配器中的值更改（基于模型）） 这是我的光标适配器：

@Override
public void bindView(View view, final Context context, Cursor cursor) {
    spotsImage = (SimpleDraweeView) view.findViewById(R.id.spotsImage);
    ivFavourite = (ImageView) view.findViewById(R.id.favouriteButton);
        ivFavourite.setTag(cursor.getString(cursor.getColumnIndex(Constants.PEEP_ID))+"tag"+cursor.getInt(cursor.getColumnIndex(Constants.PEEP_STATUS)));
    spotsTitle = (TextView) view.findViewById(R.id.titleTextView);
    followerscount = (TextView) view.findViewById(R.id.distanceTextView);

    spotsTitle.setText(cursor.getString(cursor.getColumnIndex(Constants.PEEP_NAME)));


    Uri uri = Uri.parse(cursor.getString(cursor.getColumnIndex(Constants.PEEP_PROFILE)));
    spotsImage.setImageURI(uri);

     count = cursor.getInt(cursor.getColumnIndex(Constants.PEEP_FOLLOWER_COUNT));
    if (count > 1){
        followerscount.setVisibility(View.VISIBLE);
        followerscount.setText(count+" followers");
    }
    else if (count == 1){
        followerscount.setVisibility(View.VISIBLE);
        followerscount.setText(count+" follower");
    }
    else {
        followerscount.setVisibility(View.INVISIBLE);
    }

    if (cursor.getInt(cursor.getColumnIndex(Constants.PEEP_STATUS)) == 1) {
        ivFavourite
                .setImageResource(R.drawable.favourites_tapped);
    } else {
        ivFavourite.setImageResource(R.drawable.favourites);
    }

    ivFavourite.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v){

            String [] Tags = ((String) v.getTag()).split("tag");

            if (Tags[1].equals("1")) {



                    ((ImageView) v).setImageResource(R.drawable.favourites);

            }
            else {

                    ((ImageView) v).setImageResource(R.drawable.favourites_tapped);


            }
        }
    });
}

Answer 1

随着列表进一步向上/向下滚动，指向您正在查看的填充数据的位置的引用会发生变化。换句话说，当项目离开屏幕并需要重新呈现在屏幕上时，该列表位置已经被处理并从中移动，因此数据将不正确。

我会尝试实现自定义 BaseAdapter 并扩展您的控件。如果你给我一点时间，我什至会为你做到这一点......

public class MyAdapter extends BaseAdapter {
    private Cursor cursor = null;
    private Context context = null;
    public MyAdapter(Context context, Cursor cursor)
    {
        this.context = context;
        if (cursor != null)
        {
            cursor.moveToFirst();
            this.cursor = cursor;
        }
    }
@Override
public int getCount() {
    return cursor.getCount();
}

@Override
public Object getItem(int position) {
    //processed at runtime
    return null;
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    cursor.moveToPosition(position);
    LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    convertView = inflater.inflate(R.layout.mylistitem);
    spotsImage = (SimpleDraweeView) view.findViewById(R.id.spotsImage);
    ivFavourite = (ImageView) view.findViewById(R.id.favouriteButton);
    ivFavourite.setTag(cursor.getString(cursor.getColumnIndex(Constants.PEEP_ID))+"tag"+cursor.getInt(cursor.getColumnIndex(Constants.PEEP_STATUS)));
    spotsTitle = (TextView) view.findViewById(R.id.titleTextView);
    followerscount = (TextView) view.findViewById(R.id.distanceTextView);
    Uri uri = Uri.parse(cursor.getString(cursor.getColumnIndex(Constants.PEEP_PROFILE)));
    spotsImage.setImageURI(uri);
    count = cursor.getInt(cursor.getColumnIndex(Constants.PEEP_FOLLOWER_COUNT));
    if (count > 1){
        followerscount.setVisibility(View.VISIBLE);
        followerscount.setText(count+" followers");
    }
    else if (count == 1){
        followerscount.setVisibility(View.VISIBLE);
        followerscount.setText(count+" follower");
    }
    else {
        followerscount.setVisibility(View.INVISIBLE);
    }

    if (cursor.getInt(cursor.getColumnIndex(Constants.PEEP_STATUS)) == 1) {
        ivFavourite
                .setImageResource(R.drawable.favourites_tapped);
    } else {
        ivFavourite.setImageResource(R.drawable.favourites);
    }

    ivFavourite.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v){
            String [] Tags = ((String) v.getTag()).split("tag");
            if (Tags[1].equals("1")) {
                ((ImageView) v).setImageResource(R.drawable.favourites);
            }
            else {
                ((ImageView) v).setImageResource(R.drawable.favourites_tapped);
            }
        }
    });
    return convertView;
}

}

编辑：

哦，请确保您正在实施一种方法来回收您的位图 onPause，否则您将遇到 OOM 异常

或者，如果您仍要使用 CursorAdapter，请将此方法添加到您的 SQLiteDatabase：

在你的数据库中添加方法

public void updatePeepStatusById(int id, int newStatus)
{
    SQLiteDatabase db = getWriteableDatabase();
    ContentValues cv = new ContentValues();
    cv.put(Constants.PEEP_STATUS, newStatus);
    db.update(PEEPTABLE, cv, PEEPID + " = ?", new String[{Integer.toString(id)}]);

}

然后调用： cursor.requery(); notifyDataSetChanged();

每次你想改变一个值