java - 当我尝试删除 Activity 上的操作栏时，为什么会出现此异常？

Question

我正在尝试删除下面的 LoginActivity 上的 ActionBar。我已经实现了 this 中的代码示例代码，但我不希望显示 ActionBar。我没有更改给定的代码，但我真的找不到如何删除 ActionBar(如果可能，如果不只是隐藏它)。

public class LoginActivity extends AppCompatActivity {

// Declaring View and Variables
ViewPager pager;
JoinLoginAdapter adapter;
SlidingTabLayout tabs;
CharSequence Titles[]={"Sign In","Register"};
int Numboftabs = 2;

@Override
protected void onCreate(Bundle savedInstanceState) {
    getWindow().requestFeature(Window.FEATURE_ACTION_BAR);
    getSupportActionBar().hide();
    super.onCreate(savedInstanceState);
    setContentView(R.layout.join_login);

    // Creating The ViewPagerAdapter and Passing Fragment Manager, Titles fot the Tabs and Number Of Tabs.
    adapter =  new JoinLoginAdapter(getSupportFragmentManager(),Titles,Numboftabs);

    // Assigning ViewPager View and setting the adapter
    pager = (ViewPager) findViewById(R.id.pager);
    pager.setAdapter(adapter);

    // Assiging the Sliding Tab Layout View
    tabs = (SlidingTabLayout) findViewById(R.id.tabs);
    tabs.setDistributeEvenly(true); // To make the Tabs Fixed set this true, This makes the tabs Space Evenly in Available width

    // Setting Custom Color for the Scroll bar indicator of the Tab View
    tabs.setCustomTabColorizer(new SlidingTabLayout.TabColorizer() {
        @Override
        public int getIndicatorColor(int position) {
            return getResources().getColor(R.color.tabsScrollColor);
        }
    });

    // Setting the ViewPager For the SlidingTabsLayout
    tabs.setViewPager(pager);

}

}

我尝试将 NoTheme 样式应用于 Activity ，但这给了我以下异常:

06-28 01:43:45.615  11537-11537/com.nauv.jambomall E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.nauv.jambomall/com.nauv.jambomall.ui.activity.JoinLoginActivity}: android.util.AndroidRuntimeException: requestFeature() must be called before adding content
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2294)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2348)
        at android.app.ActivityThread.access$700(ActivityThread.java:159)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:5414)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:525)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
        at dalvik.system.NativeStart.main(Native Method)
 Caused by: android.util.AndroidRuntimeException: requestFeature() must be called before adding content
        at com.android.internal.policy.impl.PhoneWindow.requestFeature(PhoneWindow.java:320)
        at com.nauv.jambomall.ui.activity.JoinLoginActivity.onCreate(JoinLoginActivity.java:28)
        at android.app.Activity.performCreate(Activity.java:5369)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2257)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2348)
at android.app.ActivityThread.access$700(ActivityThread.java:159)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5414) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:525) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
at dalvik.system.NativeStart.main(Native Method)

Answer 1

将其放入您的styles.xml

<item name="android:windowActionBar">false</item>

并扩展Activity类而不是AppCompatActivity