You need to use a Theme.AppCompat theme (or descendant) with this activity

• 具体错误

2021-11-01 20:03:17.567 14095-14095/com.serenegiant.usbcameratest E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.serenegiant.usbcameratest, PID: 14095
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.serenegiant.usbcameratest/com.serenegiant.usbcameratest.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3483)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3655)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2108)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:236)
        at android.app.ActivityThread.main(ActivityThread.java:7879)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:656)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:967)
     Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
        at androidx.appcompat.app.AppCompatDelegateImpl.createSubDecor(AppCompatDelegateImpl.java:696)
        at androidx.appcompat.app.AppCompatDelegateImpl.ensureSubDecor(AppCompatDelegateImpl.java:659)
        at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:552)
        at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:161)
        at com.serenegiant.usbcameratest.MainActivity.onCreate(MainActivity.java:63)

• 解决办法一

由继承自AppCompatActivity改为继承自Activity

• 解决办法二

第一步：在Testz\app\build.gradle，添加绿色这两句

dependencies {

    compile fileTree(dir: 'libs', include: ['*.jar'])

    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {

        exclude group: 'com.android.support', module: 'support-annotations'

    })

    compile 'com.android.support:appcompat-v7:26.0.0-alpha1'

    compile 'com.android.support:design:25.0.0'

    compile 'com.android.support.constraint:constraint-layout:1.0.0-beta5'

    testCompile 'junit:junit:4.12'

}

第二步：在我们需要的界面activity中添加，绿色部分

<activity android:name="com.chs.mt.gd_tosicke.main.MainActivity"

    android:windowSoftInputMode="stateHidden|adjustPan"

    android:theme="@style/AppThemeprice"

    android:screenOrientation="portrait"

    >

然后去style.xml添加

<style name="AppThemeprice" parent="Theme.AppCompat.Light.DarkActionBar">

    <!-- Customize your theme here. -->

</style>