如何在 value-v21 文件夹中使用样式?

How using styles in value-v21 folder?

我在 Android Studio 中创建空项目进行测试并添加 value-v21 文件夹。 android API 18 的模拟器工作正常,API 23 出现错误:

java.lang.RuntimeException: Unable to start activity ComponentInfo{ru.korshun.testapp/ru.korshun.testapp.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
                                                 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
                                                 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
                                                 at android.app.ActivityThread.-wrap11(ActivityThread.java)
                                                 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
                                                 at android.os.Handler.dispatchMessage(Handler.java:102)
                                                 at android.os.Looper.loop(Looper.java:148)
                                                 at android.app.ActivityThread.main(ActivityThread.java:5417)
                                                 at java.lang.reflect.Method.invoke(Native Method)
                                                 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                                                 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
                                              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:355)
                                                 at android.support.v7.app.AppCompatDelegateImplV9.ensureSubDecor(AppCompatDelegateImplV9.java:324)
                                                 at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:285)
                                                 at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
                                                 at ru.korshun.testapp.MainActivity.onCreate(MainActivity.java:11)
                                                 at android.app.Activity.performCreate(Activity.java:6237)
                                                 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
                                                 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
                                                 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
                                                 at android.app.ActivityThread.-wrap11(ActivityThread.java) 
                                                 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
                                                 at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                 at android.os.Looper.loop(Looper.java:148) 
                                                 at android.app.ActivityThread.main(ActivityThread.java:5417) 
                                                 at java.lang.reflect.Method.invoke(Native Method) 
                                                 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
                                                 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 

为什么?

我的values\styles.xml:

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>

values-v21\styles.xml:

<style name="AppTheme" parent="android:Theme.Material.Light.DarkActionBar">
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>

清单:

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
</application>

非常感谢!

您需要为此 activity 使用 Theme.AppCompat 主题(或后代)。 改变这个

android:theme="@style/AppTheme"

至此

android:theme="@style/Theme.AppCompat"