为什么我在 android studio 中收到与主题相关的错误?

why am I getting an Theme related error in android studio?

我正在学习如何制作启动器的教程,但出于某种原因,当我将这行代码添加到我的主 activity 清单中时,应用程序崩溃并提示我的应用程序已停止

android:theme="@android:style/Theme.Holo.Wallpaper.NoTitleBar"

10-18 15:04:25.245  18122-18122/com.example.harrops.h20droidlauncher E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.example.harrops.h20droidlauncher, PID: 18122
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.harrops.h20droidlauncher/com.example.harrops.h20droidlauncher.HomeLayout}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2400)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2458)
            at android.app.ActivityThread.access0(ActivityThread.java:172)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1305)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:146)
            at android.app.ActivityThread.main(ActivityThread.java:5598)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
            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.AppCompatDelegateImplV7.createSubDecor(AppCompatDelegateImplV7.java:309)
            at android.support.v7.app.AppCompatDelegateImplV7.ensureSubDecor(AppCompatDelegateImplV7.java:278)
            at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:252)
            at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:109)
            at com.example.harrops.h20droidlauncher.HomeLayout.onCreate(HomeLayout.java:13)
            at android.app.Activity.performCreate(Activity.java:5459)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1093)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2458)
            at android.app.ActivityThread.access0(ActivityThread.java:172)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1305)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:146)
            at android.app.ActivityThread.main(ActivityThread.java:5598)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
            at dalvik.system.NativeStart.main(Native Method)

如果我删除该应用程序运行的代码行。

任何帮助都会很棒。一如既往地提前致谢。

要更改背景,请使用:

 android:background=" "

您选择了壁纸。

试试这个

android:background="#b6db49">

下面你说要使用主题。所以你必须进入清单并在那里编辑主题

    <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:theme="@android:style/Theme.Holo.Wallpaper.NoTitleBar">

如果你已经开始你的项目默认在Android Studio main activity extends ActionBarActivity 需要 AppCompat 主题。将 Java 继承从 ActionBarActivity 更改为 Activity 并将主题保留在清单中。或者使用 AppCompat 主题。