运行应用程序时出错：找不到默认活动

Question

我是Android Studio新手。我现在正在使用它，希望获得一些错误消息，解释为什么我的APK无法在Blue Stacks中运行。 APK是在Unity中构建的。

安装Android Studio，手机模拟器等后，我仍然无法运行APK。它说：

Error running app: Default Activity not found

在Stack Overflow中有关于此错误的a post。但是，我的AndroidManifest.xml看起来很好。我也试过'无效缓存/重启'无济于事。当我进入编辑配置>启动选项>指定的活动时，我看不到任何活动供我选择。

以下是我的AndroidManifest：

<?xml version="1.0" encoding="utf-8"?>
<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:theme="@ref/0x01030006"
    android:versionCode="91"
    android:versionName="91"
    android:installLocation="2"
    package="com.quizjungle.android"
    platformBuildVersionCode="25"
    platformBuildVersionName="7.1.1">

    <supports-screens
        android:anyDensity="true"
        android:smallScreens="true"
        android:normalScreens="true"
        android:largeScreens="true"
        android:xlargeScreens="true" />

    <uses-sdk
        android:minSdkVersion="15"
        android:targetSdkVersion="25" />

    <application
        android:label="@ref/0x7f060050"
        android:icon="@ref/0x7f02004c"
        android:debuggable="false"
        android:banner="@ref/0x7f02004b"
        android:isGame="true">

        <activity
            android:label="@ref/0x7f060050"
            android:name="com.unity3d.player.UnityPlayerNativeActivity"
            android:launchMode="2"
            android:screenOrientation="1"
            android:configChanges="0x40000fff">

            <intent-filter>

                <action
                    android:name="android.intent.action.MAIN" />

                <category
                    android:name="android.intent.category.LAUNCHER" />

                <category
                    android:name="android.intent.category.LEANBACK_LAUNCHER" />
            </intent-filter>

            <meta-data
                android:name="unityplayer.UnityActivity"
                android:value="true" />

            <meta-data
                android:name="unityplayer.ForwardNativeEventsToDalvik"
                android:value="true" />
        </activity>

        <activity
            android:theme="@ref/0x01030011"
            android:name="com.facebook.unity.FBUnityLoginActivity"
            android:configChanges="0x40000fff" />

        <activity
            android:theme="@ref/0x01030011"
            android:name="com.facebook.unity.FBUnityDialogsActivity"
            android:configChanges="0x40000fff" />

        <activity
            android:name="com.facebook.unity.FBUnityAppLinkActivity"
            android:exported="true" />

        <activity
            android:name="com.facebook.unity.FBUnityDeepLinkingActivity"
            android:exported="true" />

        <activity
            android:name="com.facebook.unity.FBUnityGameRequestActivity" />

        <activity
            android:name="com.facebook.unity.FBUnityCreateGameGroupActivity" />

        <activity
            android:name="com.facebook.unity.FBUnityJoinGameGroupActivity" />

        <activity
            android:name="com.facebook.unity.AppInviteDialogActivity" />

        <meta-data
            android:name="com.facebook.sdk.ApplicationId"
            android:value="1479999760.000000" />

        <provider
            android:name="com.facebook.FacebookContentProvider"
            android:exported="true"
            android:authorities="com.facebook.app.FacebookContentProvider365740347105248" />

        <activity
            android:theme="@ref/0x01030011"
            android:name="com.chartboost.sdk.CBImpressionActivity"
            android:excludeFromRecents="true"
            android:configChanges="0x4a0"
            android:hardwareAccelerated="true" />

        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@ref/0x7f050000" />

        <activity
            android:theme="@ref/0x7f08000f"
            android:name="com.facebook.FacebookActivity"
            android:configChanges="0x5b0" />

        <activity
            android:name="com.facebook.CustomTabActivity"
            android:exported="true" />

        <activity
            android:name="com.facebook.CustomTabMainActivity" />

        <service
            android:name="com.google.android.gms.measurement.AppMeasurementService"
            android:enabled="true"
            android:exported="false" />

        <receiver
            android:name="com.google.android.gms.measurement.AppMeasurementReceiver"
            android:enabled="true"
            android:exported="false" />

        <receiver
            android:name="com.google.android.gms.measurement.AppMeasurementInstallReferrerReceiver"
            android:permission="android.permission.INSTALL_PACKAGES"
            android:enabled="true">

            <intent-filter>

                <action
                    android:name="com.android.vending.INSTALL_REFERRER" />
            </intent-filter>
        </receiver>

        <provider
            android:name="com.google.firebase.provider.FirebaseInitProvider"
            android:exported="false"
            android:authorities="com.quizjungle.android.firebaseinitprovider"
            android:initOrder="100" />

        <service
            android:name="com.google.firebase.iid.FirebaseInstanceIdService"
            android:exported="true">

            <intent-filter
                android:priority="-500">

                <action
                    android:name="com.google.firebase.INSTANCE_ID_EVENT" />
            </intent-filter>
        </service>

        <receiver
                android:name="com.google.firebase.iid.FirebaseInstanceIdReceiver"
            android:permission="com.google.android.c2dm.permission.SEND"
            android:exported="true">

            <intent-filter>

                <action
                    android:name="com.google.android.c2dm.intent.RECEIVE" />

                <action
                    android:name="com.google.android.c2dm.intent.REGISTRATION" />

                <category
                    android:name="com.quizjungle.android" />
            </intent-filter>
        </receiver>

        <receiver
        android:name="com.google.firebase.iid.FirebaseInstanceIdInternalReceiver"
            android:exported="false" />

        <activity
            android:theme="@ref/0x01030011"
            android:name="com.unity.purchasing.googleplay.PurchaseActivity"
            android:configChanges="0x40000fff" />

        <activity
            android:theme="@ref/0x0103000f"
            android:name="com.google.android.gms.ads.AdActivity"
            android:configChanges="0xfb0" />

        <activity
            android:theme="@ref/0x7f080000"
        android:name="com.google.android.gms.ads.purchase.InAppPurchaseActivity" />

        <activity
            android:theme="@ref/0x01030010"
            android:name="com.google.android.gms.common.api.GoogleApiActivity"
            android:exported="false" />
    </application>

    <uses-permission
        android:name="android.permission.INTERNET" />

    <uses-permission
        android:name="android.permission.ACCESS_NETWORK_STATE" />

    <uses-permission
        android:name="android.permission.ACCESS_WIFI_STATE" />

    <uses-permission
        android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

    <uses-permission
        android:name="android.permission.android.permission.READ_PHONE_STATE" />

    <uses-permission
        android:name="android.permission.WAKE_LOCK" />

    <permission
        android:name="com.quizjungle.android.permission.C2D_MESSAGE"
        android:protectionLevel="0x2" />

    <uses-permission
        android:name="com.google.android.c2dm.permission.RECEIVE" />

    <uses-permission
        android:name="com.quizjungle.android.permission.C2D_MESSAGE" />

    <uses-permission
        android:name="com.android.vending.BILLING" />

    <uses-feature
        android:glEsVersion="0x20000" />

    <uses-feature
        android:name="android.hardware.touchscreen"
        android:required="false" />

    <uses-feature
        android:name="android.hardware.touchscreen.multitouch"
        android:required="false" />

    <uses-feature
        android:name="android.hardware.touchscreen.multitouch.distinct"
        android:required="false" />
</manifest>

我应该怎么做才能运行APK？

*更新*

我不知道这是否有帮助。当我运行'Analyze APK ...'时，我得到以下内容：

*更新2 * Android Studio中我的清单旁边还有一个红色感叹号，上面写着“URI未注册。”，指向这一行：

xmlns:android="http://schemas.android.com/apk/res/android"

Answer 1

尝试将此代码添加到您的Manifest：

<category android:name="android.intent.category.LAUNCHER" />

Answer 2

问题可能来自清单：不要为移动设备和电视机使用相同的启动器活动，而是尝试将它们分开（不太确定）：

<application
  ...
  <activity
    android:name="com.example.android.MainActivity"
    android:label="@string/app_name" >

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

  <activity
    android:name="com.example.android.TvActivity"
    android:label="@string/app_name"
    android:theme="@style/Theme.Leanback">

    <intent-filter>
      <action android:name="android.intent.action.MAIN" />
      <category android:name="android.intent.category.LEANBACK_LAUNCHER" /> <!-- See here ?-->
    </intent-filter>

  </activity>
</application>

您还应该声明LeanBack支持：

<manifest>
    <uses-feature android:name="android.software.leanback"
        android:required="false" /> 
    ...
</manifest>

将required属性值设置为false。如果将所需属性值设置为true，则您的应用程序将仅在使用Leanback UI的设备上运行。