Question

我使用BaseAdapter在listview中创建了一个广告列表，我想从列表中删除一个广告。要删除单个广告，我必须使用异步任务请求web api，所以我在onPostExecute方法中添加了notifyDataSetChanged（）。广告已成功删除，但notifydatasetchnaged无法正常工作。我自定义BaseAdapter类如下所示，请帮助解决此问题。

public class AdsListAdapter extends BaseAdapter{

        private Activity activity;
        ArrayList<String> title;
        ArrayList<Long> adsIds;
        SessionManager sessions;        
        AlertDialogManager alert = new AlertDialogManager();
        private static LayoutInflater inflater=null;     
        String MYTAG="AdLIst";

        long userID=0;


        public AdsListAdapter(Activity a,ArrayList<String> titlelist,ArrayList<Long> adsId,long userid) {
            activity = a;          
            title=titlelist;         
            adsIds=adsId;        
            userID=userid;
            inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            sessions=new SessionManager(activity.getApplicationContext());
            imageLoader = new ImageLoader(activity.getApplicationContext());
        }


        public int getCount() {
            return title.size();
        }

        public Object getItem(int position) {
            return position;
        }

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


        public static class ViewHolder{
            public TextView titles,editicon,delicon;


        }

         @SuppressLint("NewApi") public View getView(int position, View convertView, ViewGroup parent) {
            final int id=position;
            View vi=convertView;
            ViewHolder holder;
            if(convertView==null){
                vi = inflater.inflate(R.layout.adscustomlist, null);
                holder = new ViewHolder();
                 holder.titles = (TextView) vi.findViewById(R.id.titles);
                holder.editicon= (TextView) vi.findViewById(R.id.editicon);              
                holder.delicon= (TextView) vi.findViewById(R.id.delicon);
                vi.setTag( holder );
            }
            else 
            { holder=(ViewHolder)vi.getTag(); }
            holder.titles.setText(title.get(position));
                holder.delicon.setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {                           
                            new DeleteAd(userID,adsIds.get(id)).execute();
                        }
                    }); 


            return vi;
        }




        class DeleteAd extends  AsyncTask<String,Void,Void> 
        {
             AlertDialogManager alert = new AlertDialogManager();
                private String Error = null,Message=null; 
                   long UserID =0,AdId=0;
                   boolean Status=false;

                private ProgressDialog Dialog = new ProgressDialog(activity);           

                protected void onPreExecute() {                 
                        Dialog.setMessage("Loading ...");
                        Dialog.setCanceledOnTouchOutside(false);
                        Dialog.show();

                    }

                    public DeleteAd(long UserID,long AdId) {
                        this.UserID=UserID;
                        this.AdId=AdId;

                    }


            @Override
            protected Void doInBackground(String... arg0) {
                JSONObject json;                
                try {
                    json = new JSONObject(postDataAdDelete());
                    Message=json.getString("Message");
                    Status = json.getBoolean("Status");                 
                } catch (JSONException e) {                 
                    e.printStackTrace();
                }
                return null;
            }
              protected void onPostExecute(Void unused) {
                  Dialog.dismiss();
                  alert.showAlertDialog(activity, "Ad Delete", Message, Status);
                  notifyDataSetChanged();

            }
        }




}

Answer 1

您必须删除列表标题中要删除的位置的值。尝试title.remove（位置）

Answer 2

AdsListAdapter adapter = new AdsListAdapter (Activity ,ArrayList<String> ,ArrayList<Long> ,long );//pass the value 
adapter.notifyDataSetChanged();

Answer 3

尝试像这样调用notifyDataSetChanged()方法

activity.runOnUiThread(new Runnable() {
                @Override
                public void run() {
                        notifyDataSetChanged();
                }
            });

notifyDataSetChanged在BaseAdapter类中的AsyncTask中不起作用

3 个答案: