Java 不幸的是,Listview已停止工作(android错误)
当我使用android emulator运行代码时,我遇到了“不幸的是,您的listview已停止工作”的问题。 请看一下我的密码谢谢 对于activity_main.xml:Java 不幸的是,Listview已停止工作(android错误),java,android,listview,Java,Android,Listview,当我使用android emulator运行代码时,我遇到了“不幸的是,您的listview已停止工作”的问题。 请看一下我的密码谢谢 对于activity_main.xml: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.androi
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
android:orientation="vertical"
tools:context="com.example.it3783.listview.MainActivity">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Choose a location..."/>
<ListView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:drawSelectorOnTop="false"
android:id="@+id/spLocations"></ListView>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@+id/superHerosTV"
/>
</LinearLayout>
对于MainActivity.java:
public class MainActivity extends AppCompatActivity {
ArrayAdapter<CharSequence>adapter;
TextView tvSelection;
ListView lvLocation;
String []strArray;
String []superHeros = {"1. Batman\n 2. SpiderMan", "1. Peter Pan\n2. Superman",
"1. IronMan\n2. Peter Pan", "1. SnowWhite \n2. Gingerbreadman"};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
adapter = new ArrayAdapter<CharSequence>(this, android.R.layout.simple_list_item_1, strArray);
tvSelection = (TextView) findViewById(R.id.superHerosTV);
lvLocation = (ListView) findViewById(R.id.spLocations);
Resources myRes = this.getResources();
strArray = myRes.getStringArray(R.array.locationArea);
lvLocation.setAdapter(adapter);
lvLocation.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String text = strArray[position];
tvSelection.setText(text);
}
});
adapter = ArrayAdapter.createFromResource(this, R.array.locationArea, android.R.layout.simple_list_item_1);
}
}
public类MainActivity扩展了AppCompatActivity{
ArrayAdapter;
文本视图选择;
列表视图位置;
字符串[]strArray;
String[]超级英雄={“1.蝙蝠侠\n 2.蜘蛛侠”,“1.彼得·潘\n 2.超人”,
“1.铁人\n2.彼得·潘”,“1.白雪公主\n2.姜饼人”};
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
adapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,strArray);
tvSelection=(文本视图)findViewById(R.id.superHerosTV);
lvLocation=(ListView)findViewById(R.id.spLocations);
Resources myRes=this.getResources();
strArray=myRes.getStringArray(R.array.locationArea);
lvLocation.setAdapter(适配器);
lvLocation.setOnItemClickListener(新的AdapterView.OnItemClickListener(){
@凌驾
public void onItemClick(AdapterView父对象、视图、整型位置、长id){
字符串文本=strArray[位置];
tvSelection.setText(文本);
}
});
adapter=ArrayAdapter.createFromResource(这个,R.array.locationArea,android.R.layout.simple\u list\u item\u 1);
}
}
对于strings.xml:
<resources>
<string name="app_name">ListView</string>
<string-array name="locationArea">
<item>North</item>
<item>South</item>
<item>East</item>
<item>West</item>
</string-array>
</resources>
列表视图
北
南方
东
西
adapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,strArray);
onCreate方法中的这一行接受strArray,它未初始化,因此其值为null。
现在,当您将带有空数据的适配器设置到listview时,它会崩溃。将堆栈跟踪放在这里
adapter = new ArrayAdapter<CharSequence>(this,android.R.layout.simple_list_item_1, strArray);