RuntimeException:填充类片段时出错

Question

我使用以下代码获取runtimeException,有人知道为什么吗？

public class FragsApplicationActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

SuggestionFrags类

public class SuggestionFrags extends Fragment{
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        return super.onCreateView(inflater, container, savedInstanceState);
    }

}

main.xml中

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <fragment
        android:id="@+id/fragment1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        class="com.samplefragsapplication.SuggestionFrags" />

</LinearLayout>

我得到这个例外:

11-23 18:09:23.899: E/AndroidRuntime(2436): FATAL EXCEPTION: main
11-23 18:09:23.899: E/AndroidRuntime(2436): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.samplefragsapplication/com.samplefragsapplication.FragsApplicationActivity}: android.view.InflateException: Binary XML file line #2: Error inflating class fragment
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.os.Looper.loop(Looper.java:123)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.ActivityThread.main(ActivityThread.java:4627)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at java.lang.reflect.Method.invokeNative(Native Method)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at java.lang.reflect.Method.invoke(Method.java:521)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at dalvik.system.NativeStart.main(Native Method)
11-23 18:09:23.899: E/AndroidRuntime(2436): Caused by: android.view.InflateException: Binary XML file line #2: Error inflating class fragment
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:576)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.inflate(LayoutInflater.java:385)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:198)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.Activity.setContentView(Activity.java:1647)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at com.samplefragsapplication.FragsApplicationActivity.onCreate(FragsApplicationActivity.java:12)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
11-23 18:09:23.899: E/AndroidRuntime(2436): Caused by: java.lang.ClassNotFoundException: android.view.fragment in loader dalvik.system.PathClassLoader[/data/app/com.samplefragsapplication-2.apk]
11-23 18:09:23.899: E/AndroidRuntime(2436):     at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.createView(LayoutInflater.java:466)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.onCreateView(LayoutInflater.java:544)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:66)
11-23 18:09:23.899: E/AndroidRuntime(2436):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:563)

Answer 1

如果你要使用Fragments你需要扩展FragmentActivity不是Activity.

Answer 2

要解决此问题,您必须从FragsApplicationActivity中的FragmentActivity而不是Activity扩展.

Answer 3

正确的形式是

<fragment
    android:id="@+id/fragment1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:name="com.samplefragsapplication.SuggestionFrags" />

UPD：根据 logcat 输出判断，您没有可用的片段。如果您运行的是 Honeycomb 之前的 Android（但 >= 1.6），则可以使用兼容性库。Fragment 是在 3.0 中引入的。