Android 当尝试将我的应用程序从标题栏中删除时，我的应用程序崩溃

如果您不想同时显示标题和动作栏，则可以编写 在onCreate（）方法中 getSupportActionBar（）.hide（）

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="uk.co.willmudgelive.ketimer">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@android:style/Theme.Black.NoTitleBar">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

D/AndroidRuntime: Shutting down VM E/AndroidRuntime: FATAL EXCEPTION: main Process: uk.co.willmudgelive.ketimer, PID: 21308 java.lang.RuntimeException: Unable to start activity ComponentInfo{uk.co.willmudgelive.ketimer/uk.co.willmudgelive.ketimer.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity. at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3253) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3349) at android.app.ActivityThread.access$1100(ActivityThread.java:221) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:158) at android.app.ActivityThread.main(ActivityThread.java:7224) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity. at android.support.v7.app.AppCompatDelegateImplV9.createSubDecor(AppCompatDelegateImplV9.java:347) at android.support.v7.app.AppCompatDelegateImplV9.ensureSubDecor(AppCompatDelegateImplV9.java:316) at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:281) at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140) at uk.co.willmudgelive.ketimer.MainActivity.onCreate(MainActivity.java:26) at android.app.Activity.performCreate(Activity.java:6876) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1135) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3206) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3349)  at android.app.ActivityThread.access$1100(ActivityThread.java:221)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)  at android.os.Handler.dispatchMessage(Handler.java:102)  at android.os.Looper.loop(Looper.java:158)  at android.app.ActivityThread.main(ActivityThread.java:7224)  at java.lang.reflect.Method.invoke(Native Method)  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)  I/Process: Sending signal. PID: 21308 SIG: 9 Disconnected from the target VM, address: 'localhost:8602', transport: 'socket'