为什么微调器活动没有运行？错误：不幸的是，spinnerapp已被停止

Question

我的问题是，当我运行微调代码时，它显示错误

“不幸的是spinnerApp已被停止”

下面是我的xml文件：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">


<Spinner
    android:id="@+id/spinner"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:layout_alignParentStart="true"
    android:layout_alignParentTop="true"
    android:layout_marginTop="113dp"
    android:layout_alignParentLeft="true" />
</RelativeLayout>

下面是我的strings.xml：

<resources>
<string name="app_name">SpinnerApp</string>
<string-array name="myarray">
    <item value="Oswald">Oswald</item>
    <item value="Noddy">Noddy</item>
    <item value="Shinchan">Shinchan</item>
    <item value="Doraemon">Doraemon</item>
    <item value="Detective Conan">Detective Conan</item>
    <item value="Power puff girls">Power puff girls</item>
    <item value="Ojarumaru">Ojarumaru</item>
    <item value="Bob the builder">Bob the builder</item>
    <item value="Asari chan">Asari chan</item>
    <item value="Maruko chan">Maruko chan</item>
    <item value="Mighty masked cat niyander">Mighty masked cat niyander</item>

</string-array>

下面是我的.java文件：

package com.example.mypc.spinnerapp;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.*;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
Spinner sp;
ArrayAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    sp=(Spinner)findViewById(R.id.spinner);
    List<String> list=new ArrayList<String>();
    list.add("Hello");
    list.add("World");
    list.add("How");
    list.add("are");
    list.add("you");

    String []arr=getResources().getStringArray(R.array.myarray);
    ArrayAdapter<String> adapter=new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,list);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    sp.setAdapter(adapter);
    sp.setOnItemClickListener(new AdapterView.OnItemClickListener() {
       @Override
       public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
           sp.setSelection(position);
       }
   });


}
}

我的代码有什么问题吗？请提供解决方案谢谢你提前