ArrayAdapter的Android Parse.com错误[应用程序崩溃]

Question

我在使用ParseObject时遇到问题，首先尝试使用ListActivity但应用程序崩溃了，然后看到堆栈溢出上的几个帖子也没有用，关于Parse类的细节很少

Class Name : Events
Fields: String event_name;
        String date;
        String time;
        String event_venue;
        String speaker;
        int fee;
        String event_description;

当我尝试初始化适配器时，程序中的错误仍然存​​在。

我的代码如下

Events.java

public class Events extends ParseObject {
    private String event_name;
    private String date;
    private String time;
    private String event_venue;
    private String speaker;
    private int fee;
    private String event_description;

    public Events(String event_name, String date, String time, String event_venue, String speaker, int fee, String event_description) {
        this.event_name = event_name;
        this.date = date;
        this.time = time;
        this.event_venue = event_venue;
        this.speaker = speaker;
        this.fee = fee;
        this.event_description = event_description;
    }

    public String getEvent_name() {
        return event_name;
    }

    public void setEvent_name(String event_name) {
        this.event_name = event_name;
    }

    public String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

    public String getTime() {
        return time;
    }

    public void setTime(String time) {
        this.time = time;
    }

    public String getEvent_venue() {
        return event_venue;
    }

    public void setEvent_venue(String event_venue) {
        this.event_venue = event_venue;
    }

    public String getSpeaker() {
        return speaker;
    }

    public void setSpeaker(String speaker) {
        this.speaker = speaker;
    }

    public int getFee() {
        return fee;
    }

    public void setFee(int fee) {
        this.fee = fee;
    }

    public String getEvent_description() {
        return event_description;
    }

    public void setEvent_description(String event_description) {
        this.event_description = event_description;
    }
}

Events_Activity.java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;

import com.parse.FindCallback;
import com.parse.ParseException;
import com.parse.ParseQuery;

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

public class Event_Activity extends AppCompatActivity {
    private List<Events> mEvents= new ArrayList<Events>();
    private String e_name;
    private String e_date;
    private String e_time;
    private String e_venue;
    private String e_speaker;
    private int e_fee;
    private String e_description;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_event_);

        ParseQuery<Events> event_query = new ParseQuery<Events>("Events");
        event_query.findInBackground(new FindCallback<Events>() {
            @Override
            public void done(List<Events> list, ParseException e) {
                if(e != null){
                    Toast.makeText(Event_Activity.this,"Exception : "+e,Toast.LENGTH_LONG).show();
                }
                for (Events event : list){
                    e_name = event.getEvent_name();
                    e_date = event.getDate();
                    e_time = event.getTime();
                    e_venue = event.getEvent_venue();
                    e_speaker = event.getSpeaker();
                    e_fee = event.getFee();
                    e_description = event.getEvent_description();
                    Events new_event = new Events(e_name,e_date,e_time,e_venue,e_speaker,e_fee,e_description);
                    mEvents.add(new_event);
                }
            }
        });


       ArrayAdapter<Events> value = new ArrayAdapter<Events>(Event_Activity.this,android.R.layout.simple_list_item_1, android.R.id.text1, mEvents);


        ListView  v = (ListView)findViewById(R.id.eventlistView);
        v.setAdapter(value);

activity_event_.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.cse.Event_Activity">

    <ListView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/eventlistView">

    </ListView>

</RelativeLayout>