Logcat error-Content must have a ListView whose id attribute is 'android.R.id.list'

Question

My list view is showing error like this what i mention in my question,eventhough i mention in mainactivity extends listactivity also and my layout i put as listview

activity_list_item.xml

<LinearLayout 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=".MainActivity" >

    <ListView
        android:id="@android:id/list"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent" >
    </ListView>

</LinearLayout>

Mainactivity.java

public class MainActivity extends ListActivity implements FetchDataListener{
    private ProgressDialog dialog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);        
        setContentView(R.layout.activity_list_item);   
        initView();   
    }

    private void initView() {
        // show progress dialog
        dialog = ProgressDialog.show(this, "", "Loading...");

        String url = "http://10.0.2.2/test/apps.php";
        FetchDataTask task = new FetchDataTask(this);
        task.execute(url);
    }

    @Override
    public void onFetchComplete(List<Application> data) {
        // dismiss the progress dialog
        if(dialog != null)  dialog.dismiss();
        // create new adapter
        ApplicationAdapter adapter = new ApplicationAdapter(this, data);
        // set the adapter to list
        setListAdapter(adapter);        
    }

    @Override
    public void onFetchFailure(String msg) {
        // dismiss the progress dialog
        if(dialog != null)  dialog.dismiss();
        // show failure message
        Toast.makeText(this, msg, Toast.LENGTH_LONG).show();        
    }
}

My log cat error is showing like this

5-17 11:30:30.649: E/AndroidRuntime(1177): FATAL EXCEPTION: main
05-17 11:30:30.649: E/AndroidRuntime(1177): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.jsonandroid/com.example.jsonandroid.MainActivity}: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.os.Looper.loop(Looper.java:137)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ActivityThread.main(ActivityThread.java:5039)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at java.lang.reflect.Method.invokeNative(Native Method)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at java.lang.reflect.Method.invoke(Method.java:511)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at dalvik.system.NativeStart.main(Native Method)
05-17 11:30:30.649: E/AndroidRuntime(1177): Caused by: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ListActivity.onContentChanged(ListActivity.java:243)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:273)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.Activity.setContentView(Activity.java:1881)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at com.example.jsonandroid.MainActivity.onCreate(MainActivity.java:17)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.Activity.performCreate(Activity.java:5104)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
05-17 11:30:30.649: E/AndroidRuntime(1177):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
05-17 11:30:30.649: E/AndroidRuntime(1177):     ... 11 more

Answer 1

您只需要将activity_list_item.xml中的列表视图ID更改为@android：id / list，如果您使用ListActivity，则listview ID必须像上面提到的那样

Answer 2

Change your layout to,

    <?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />

Answer 3

Remove the call to setContentView .

ListActivity does not require that you assign a layout to it via the setContentView() method, if you only want to show a ListView ListActivity contains by default a ListView.

In case you need to include more Views than a ListView in your ListActivity you can still assign a layout to your activity. In this case your layout must contain a ListView with the android:id attribute set to @android:id/list .