从Parse框架查询（类：具有1行的事件）不起作用，并且在Android Studio的片段布局上不显示

Question

我正在使用具有片段活动支持的列表视图的活动。 从Back4app上的Parse Framework接收的数据夸大了该片段

以下是该片段的代码：-

package com.footzila.footify;


import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import com.parse.FindCallback;
import com.parse.GetCallback;
import com.parse.ParseException;
import com.parse.ParseObject;
import com.parse.ParseQuery;
import com.squareup.picasso.Picasso;

import java.util.ArrayList;
import java.util.List;


/**
 * A simple {@link Fragment} subclass.
 */
public class NewsFragment extends Fragment
{
    //private List<String> mNewsList;
    private ListView lv;
    private List<Events> myEvents;
    public NewsFragment() {
        // Required empty public constructor
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View fragmentView= inflater.inflate(R.layout.fragment_news, container, false);
        lv = (ListView) fragmentView.findViewById(R.id.MyListView);
      //  mNewsList =new ArrayList<String>();
        myEvents = new ArrayList<Events>();

        /**
        mNewsList.add("My first Item");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
        mNewsList.add("Some MoreItem");
**/
        ParseQuery<ParseObject> query = ParseQuery.getQuery("Events");
        //query.whereEqualTo("playerEmail", "dstemkoski@example.com");
        query.findInBackground(new FindCallback<ParseObject>(){
            public void done(List<ParseObject> obj, ParseException e)
            {
                if(e == null)
                {
                    Log.d("score", "Retrieved the object." +obj.size());
                    for(ParseObject parseObject : obj )
                    {
                        String title = (String)parseObject.get("Title");
                        String link = (String)parseObject.get("Link");
                        String imgLink = (String)parseObject.get("Imlink");
                        Events ev =new Events(title,imgLink,link);
                        myEvents.add(ev);
                        myEvents.add(new Events("ABC", "https://qph.ec.quoracdn.net/main-thumb-62579190-50-tdsgvwmqywsdhbkoosmzkhrumpkzcxxq.jpeg","www.google.com"));
                    }
                    lv.setAdapter(new MyAdapter());
                }
                else  {
                    Log.d("score", "The getFirst request failed.");
                }
            }
        });


        return fragmentView;
    }

    private class MyAdapter extends BaseAdapter
    {
        @Override
        public int getCount() {
            return myEvents.size();
        }

        @Override
        public Object getItem(int i) {
            return myEvents.get(i);
        }

        @Override
        public long getItemId(int i) {
            return 0;
        }

        @Override
        public View getView(int i, View view, ViewGroup viewGroup)
        {
            View rV=getActivity().getLayoutInflater().inflate(R.layout.row,null);
            Events rowEvent = myEvents.get(i);
            TextView tv = (TextView) rV.findViewById(R.id.textView);
            tv.setText(rowEvent.getTitle());
            ImageView iv= (ImageView)rV.findViewById(R.id.imageView2);
            Picasso.with(getActivity()).load(rowEvent.getImgLink()).into(iv);//"http://i.imgur.com/DvpvklR.png"
            return rV;
        }
    }
}

在Parse Framework中，有一个类名“ Events”，带有3个字符串Title，ImLink，Link

具有片段布局的MainActivity具有以下代码

package com.footzila.footify;

import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import com.parse.Parse;

public class MainActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        Parse.initialize(this,"pQMefFCLGJ2PejA3dJO3EaEil3AD63SNRbSNGW9m","KkJDsaNKR8tOHkjRLp6ISCV67xF1pMAWQzyVicSI"); //App id and client key
        setContentView(R.layout.activity_main);

    }
}

Answer 1

恐怕您的MainActivity代码的“ Parse.initialize”部分可能不完整。 请注意，您需要将服务器URL指向主机（在本例中为Back4App的URL），并实际触发“ build（）”。

我建议您将特定部分更改为以下内容：

Parse.initialize(new Parse.Configuration.Builder(this)
                .applicationId("YOUR_APP_ID")
                .clientKey("YOUR_CLIENT_KEY")
                .server("https://parseapi.back4app.com/").build()
);

我认为这可以为查询提供适当的结果。