Android Studio从2.2升级到3.1.2后Manifest.xml报未知元素错误求助

嘿，我一眼就发现你manifest里的问题了——你把MainActivity的activity标签嵌套在VerificationActivity的标签里面了！Android的Manifest文件中，所有<activity>标签都必须是<application>的直接子元素，绝对不能互相嵌套，这就是升级Android Studio后触发这个报错的核心原因。

修正后的完整Manifest代码 #

<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

<application
    android:name=".SplashTimer"
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity
        android:name=".SplashScreenActivity"
        android:theme="@style/SplashTheme">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".HomeActivity"
        android:screenOrientation="portrait"
        android:theme="@style/Theme.AppCompat.NoActionBar" />
    <activity android:name=".VerificationActivity" />
    <activity
        android:name=".MainActivity"
        android:screenOrientation="portrait" />
    <activity
        android:name=".DashboardActivity"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".LoginActivity"
        android:theme="@style/Theme.AppCompat.NoActionBar"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".ProblemsActivity"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".TotalActivity"
        android:theme="@style/Theme.AppCompat.NoActionBar"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".FirstPayment"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".FirstPaymentInformation"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".DeclineQuestionsActivity"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".LIkelyProblemsActivity"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".TotalAmountActivity"
        android:theme="@style/Theme.AppCompat.NoActionBar"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".ThanksActivity"
        android:screenOrientation="portrait"/>
    <activity
        android:name=".SignUpActivity"
        android:theme="@style/SignUpTheme"
        android:screenOrientation="portrait"/>
    <activity android:name=".StripePayment" />
    <activity
        android:name=".PaymentActivity"
        android:label="@string/title_activity_payment"
        android:screenOrientation="portrait"
        android:theme="@style/AppTheme.NoActionBar" />
    <activity android:name=".LocationActivity" />
    <activity android:name=".SecondPayment" />
    <activity
        android:name=".DriverPayment"
        android:screenOrientation="portrait"></activity>
    <!-- ATTENTION: This was auto-generated to add Google Play services to your project for App Indexing. -->
    <meta-data
        android:name="com.google.android.gms.version"
        android:value="@integer/google_play_services_version" />
</application>

额外说明 #

升级到Android Studio 3.1.2后，IDE对Manifest文件的语法检查变得更严格了，之前可能没报错的结构问题现在会被直接检测出来。替换完修正后的代码后，记得同步一下Gradle项目，应该就能解决这个报错了。

内容的提问来源于stack exchange，提问作者user2940930