使用适配器从arraylist错误填充ListView

Question

尝试使用从另一个活动传递的arraylist填充listview时，我一直收到错误。我输入的适配器代码与我在另一个活动中完全相同，它接受用户输入，添加到数组并填充列表工作正常但不在这里。我这里有两个列表，因为我一直在尝试测试其中一个。

班级：

package com.liftlover.mitchell.workoutapplication;

import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;

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

public class RoutineDetail extends AppCompatActivity {
TextView routineTxt;
ListView lv;
List<String> excersiseList;



@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_routine_detail);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    Intent intentData = getIntent();
    String getRoutine = intentData.getStringExtra("routine");
    routineTxt = (TextView) findViewById(R.id.routineText);
    routineTxt.setText(getRoutine);


    lv = (ListView) findViewById(R.id.routineListView);


    excersiseList = intentData.getStringArrayListExtra("excersiseList");
    List<String> list = new ArrayList<String>();
    list.add("wegewgW");
    list.add("robnwgn");
    list.add("q[3gng");


   ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(RoutineDetail.this,android.R.layout.simple_list_item_1,list );

   lv.setAdapter(arrayAdapter);
}

}

错误（我无法正确格式化抱歉）：

Process: com.liftlover.mitchell.workoutapplication, PID: 2195
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.liftlover.mitchell.workoutapplication/com.liftlover.mitchell.workoutapplication.RoutineDetail}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
 at android.app.ActivityThread.-wrap11(ActivityThread.java)
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
 at android.os.Handler.dispatchMessage(Handler.java:102)
 at android.os.Looper.loop(Looper.java:148)
 at android.app.ActivityThread.main(ActivityThread.java:5417)
 at java.lang.reflect.Method.invoke(Native Method)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
 at com.liftlover.mitchell.workoutapplication.RoutineDetail.onCreate(RoutineDetail.java:49)
 at android.app.Activity.performCreate(Activity.java:6237)
 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
 at android.app.ActivityThread.-wrap11(ActivityThread.java) 
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
 at android.os.Handler.dispatchMessage(Handler.java:102) 
 at android.os.Looper.loop(Looper.java:148) 
 at android.app.ActivityThread.main(ActivityThread.java:5417) 
 at java.lang.reflect.Method.invoke(Native Method) 
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)