如何使ListView在android中与ArrayAdapter一起工作
为了解决那个问题,我已经忙了好几个小时了。我将解释我的代码结构 我有两个类如何使ListView在android中与ArrayAdapter一起工作,android,listview,android-arrayadapter,Android,Listview,Android Arrayadapter,为了解决那个问题,我已经忙了好几个小时了。我将解释我的代码结构 我有两个类TwitterActivity(主要活动)和SearchTwitter。在twitter活动中我登录,然后启动SearchTwitter活动。我还有他们的xml布局文件,activity\u twitter.xml和search.xml 这些类看起来像: public class TwitterActivity extends Activity { private Button mSignin; @Ov
TwitterActivity
(主要活动)和SearchTwitter
。在twitter活动中
我登录,然后启动SearchTwitter
活动。我还有他们的xml布局文件,activity\u twitter.xml
和search.xml
这些类看起来像:
public class TwitterActivity extends Activity
{
private Button mSignin;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_twitter);
mSignin = (Button)findViewById(R.id.login_id);
mSignin.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
//startSiginingProcess(...)
Intent intent = new Intent(TwitterActivity.this, SearchTwitter.class);
startActivity(intent);
}
}
});
}
activity\u twitter.xml
只有一个按钮,即登录按钮。SearchTwitter
活动如下所示:
public class SearchTwitter extends ListActivity {
private Button buttonLogout;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.search);
initializeComponent();
initControl();
/********************************************************/
ArrayList<String> events = new ArrayList<String>();
events.add("Item1");
events.add("Item2");
ListView ls = (ListView) findViewById(R.id.list);
ls.setAdapter(new ArrayAdapter<String> (this, R.layout.search, events));
/********************************************************/
}
private void initControl()
{
//Finish Signing procces
}
private void initializeComponent(){
buttonLogout = (Button) findViewById(R.id.buttonLogout);
buttonLogout.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
//Just LogOut
});
}
我现在有什么问题
- 在
活动中,我扩展了SearchTwitter
ListActivity
- 我想做的就是让
中被星星包围的代码正常工作。我尝试了很多方法,但没有结果。我的应用程序总是崩溃SearchTwitter
ListView ls=(ListView)findviewbyd(R.layout.search)的情况下代码>我得到:
06-22 04:14:39.648: E/AndroidRuntime(1861): FATAL EXCEPTION: main
06-22 04:14:39.648: E/AndroidRuntime(1861): Process: com.bledi.android.twittertest, PID: 1861
06-22 04:14:39.648: E/AndroidRuntime(1861): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.bledi.android.twittertest/com.bledi.android.twittertest.SearchTwitter}: java.lang.NullPointerException
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.ActivityThread.access$800(ActivityThread.java:135)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.os.Handler.dispatchMessage(Handler.java:102)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.os.Looper.loop(Looper.java:136)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.ActivityThread.main(ActivityThread.java:5017)
06-22 04:14:39.648: E/AndroidRuntime(1861): at java.lang.reflect.Method.invokeNative(Native Method)
06-22 04:14:39.648: E/AndroidRuntime(1861): at java.lang.reflect.Method.invoke(Method.java:515)
06-22 04:14:39.648: E/AndroidRuntime(1861): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
06-22 04:14:39.648: E/AndroidRuntime(1861): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
06-22 04:14:39.648: E/AndroidRuntime(1861): at dalvik.system.NativeStart.main(Native Method)
06-22 04:14:39.648: E/AndroidRuntime(1861): Caused by: java.lang.NullPointerException
06-22 04:14:39.648: E/AndroidRuntime(1861): at com.bledi.android.twittertest.SearchTwitter.onCreate(SearchTwitter.java:38)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.Activity.performCreate(Activity.java:5231)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
06-22 04:14:39.648: E/AndroidRuntime(1861): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
编辑2
我更改了ListView ls=(ListView)findviewbyd(R.id.list)
toListView ls=(ListView)findViewById(android.R.id.list)
和ls.setAdapter(新的ArrayAdapter(this,R.layout.search,events))
tols.setAdapter(新的ArrayAdapter(this,R.layout.search,android.R.id.text1,events))
我得到了一个无崩溃的应用程序,但其行为很奇怪。当您的活动扩展到ListActivity
时,无需在活动中再次定义listview
。
因此,请删除此行
ListView ls = (ListView) findViewById(R.id.list);
试着改变
ls.setAdapter(new ArrayAdapter<String> (this, R.layout.search, events));
ls.setAdapter(新的ArrayAdapter(this,R.layout.search,events));
到
setListAdapter(新的ArrayAdapter(这个,android.R.layout.simple_list_item_1,事件));
其中simple\u list\u item\u 1
是Android内部布局视图请发布logcat异常。@Girubai我在上面提到过它。这段代码不编译正如你所说,应用程序总是崩溃,不管怎样,编译错误是什么?好的,我将发布一个案例,其中我设置了`ListView ls=(ListView)findViewById(R.layout.search)`listView和适配器代码看起来是合法的。必须是starsOk代码中的内容,但是ListView ls=(ListView)findViewById(R.id.list)呢代码>?ListView ls=getListView()@BlediBoss乐于帮助,享受编码。
ls.setAdapter(new ArrayAdapter<String> (this, R.layout.search, events));
setListAdapter(new ArrayAdapter<String> (this, android.R.layout.simple_list_item_1 ,events));