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我正在开发一个可扩展的列表视图应用程序，我想在其上添加操作栏。

对于操作栏的可见性，我似乎需要扩展 ActionBarActivity 类，但要运行我的可扩展列表活动，我应该扩展活动类。

所以，我改变了以下代码

从

public class Time extends Activity {

至

public class Time extends ActionBarActivity {

假设以下层次结构

java.lang.Object
   ↳    android.content.Context
       ↳    android.content.ContextWrapper
           ↳    android.view.ContextThemeWrapper
               ↳    android.app.Activity
                   ↳    android.support.v4.app.FragmentActivity
                       ↳    android.support.v7.app.ActionBarActivity

但是，当我现在运行我的应用程序时，我得到空指针异常 super.onCreate(savedInstanceState);

请在此处查看日志：

12-19 00:10:48.995  14128-14128/sudharshanapps.clock E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: sudharshanapps.clock, PID: 14128
    java.lang.RuntimeException: Unable to start activity ComponentInfo{sudharshanapps.clock/sudharshanapps.clock.Time}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2198)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
            at android.app.ActivityThread.access$800(ActivityThread.java:139)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5086)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
            at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:151)
            at android.support.v7.app.ActionBarActivityDelegateBase.onCreate(ActionBarActivityDelegateBase.java:138)
            at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:123)
            at sudharshanapps.clock.Time.onCreate(Time.java:247)
            at android.app.Activity.performCreate(Activity.java:5248)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1110)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2162)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
            at android.app.ActivityThread.access$800(ActivityThread.java:139)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5086)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
            at dalvik.system.NativeStart.main(Native Method)

您能否建议，这里缺少什么或在哪里寻找任何参考或想法。

4

1 回答 1

2

更改清单文件从

<application
        android:allowBackup="true"
        android:icon="@drawable/logo"
        android:label="Time across Globe"
        android:theme="@style/AppTheme" >

至

<application
        android:allowBackup="true"
        android:icon="@drawable/logo"
        android:label="Time across Globe"
        android:theme="@style/Theme.AppCompat.Light" >

它解决了这个问题

于 2014-12-18T18:57:27.660 回答