Android中的Options Menu（）存在问题

可能重复：

当我像这样调用openOptionsMenu（）时：

@Override
public void onCreate(Bundle bundle)
{
    super.onCreate(bundle);
    setContentView(R.layout.home_screen);

    layout = (LinearLayout) findViewById(R.id.wrapper1);
    layout.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            openOptionsMenu();
        }
    });

}

@Override
public void onCreate(Bundle bundle)
{
    super.onCreate(bundle);
    setContentView(R.layout.home_screen);

    openOptionsMenu();      
}

…它工作得很好，但如果我这样称呼它：

@Override
public void onCreate(Bundle bundle)
{
    super.onCreate(bundle);
    setContentView(R.layout.home_screen);

    layout = (LinearLayout) findViewById(R.id.wrapper1);
    layout.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            openOptionsMenu();
        }
    });

}

@Override
public void onCreate(Bundle bundle)
{
    super.onCreate(bundle);
    setContentView(R.layout.home_screen);

    openOptionsMenu();      
}

我收到此错误并重新启动应用程序：

11-15 11:34:05.218: E/AndroidRuntime(1663): FATAL EXCEPTION: main
11-15 11:34:05.218: E/AndroidRuntime(1663): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.toparound.logic/com.toparound.logic.HomeScreen}: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.ActivityThread.access$600(ActivityThread.java:130)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.os.Looper.loop(Looper.java:137)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.ActivityThread.main(ActivityThread.java:4745)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at java.lang.reflect.Method.invokeNative(Native Method)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at java.lang.reflect.Method.invoke(Method.java:511)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at dalvik.system.NativeStart.main(Native Method)
11-15 11:34:05.218: E/AndroidRuntime(1663): Caused by: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.view.ViewRootImpl.setView(ViewRootImpl.java:585)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:326)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.view.Window$LocalWindowManager.addView(Window.java:547)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at com.android.internal.policy.impl.PhoneWindow.openPanel(PhoneWindow.java:630)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at com.android.internal.policy.impl.PhoneWindow.openPanel(PhoneWindow.java:508)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.Activity.openOptionsMenu(Activity.java:2800)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at com.toparound.logic.HomeScreen.onCreate(HomeScreen.java:24)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.Activity.performCreate(Activity.java:5008)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
11-15 11:34:05.218: E/AndroidRuntime(1663):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)

奇怪，啊哈！！！，因为我希望最后一种方法是，一旦创建活动，optionsMenu（）就会自动填充。另一方面，如果我在onClick事件处理程序中调用openOptionsMenu（），它就会工作。请有人帮助我。

---

提前感谢。

您的活动尚未在第二个片段中创建。如果未创建主活动，则它没有窗口，因此无法像菜单一样打开子窗口。您需要在onCreate完成后调用它。最好的方法是使用处理程序或runnable，并在其中调用openOptionsMenu。

我不明白为什么在第一个代码段中创建活动，而在第二个代码段中不创建活动。在第一个代码段中，您在click listener中调用实际的open。所以在你点击屏幕之前它不会被调用。执行此操作时，onCreate函数已完成，窗口已创建。