无法实例化 activity 组件信息 Class 未找到异常 Android

Question

我的应用程序无一例外地直接部署到任何设备。但是安装 .apk 时会抛出以下异常。其次，它在 Nougat 7.0 及更高版本上运行良好，但在较低的 OS 版本（如 5.0 和 6.0）中崩溃并出现相同的异常。 etc. 异常的原因是什么？

Manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="amitechnologies.products.apps.equalizeraudioplayer.v3" >

    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_INTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.BATTERY_STATS" />
    <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme">

        <activity
            android:name="amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles"
            android:label="@string/app_name"
            android:configChanges="keyboard|keyboardHidden|orientation|screenSize" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <activity
            android:name="amitechnologies.products.apps.equalizeraudioplayer.v3.view.MainActivity"
            android:screenOrientation="sensorPortrait"
            android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
            android:label="@string/app_name" >
        </activity>

    </application>

</manifest>

Build.gradle:

 apply plugin: 'com.android.application'
android {
    signingConfigs {
        config {
            keyAlias 'm-zaes'
            keyPassword 'm-zaes'
            storeFile file('D:/AMI_Repo/AMI_Designer/Targets/Android/AMI 3d Player v3/keystore.jks')
            storePassword 'm-zaes'
        }
    }
    compileSdkVersion 25
    buildToolsVersion "25.0.1"
    useLibrary 'org.apache.http.legacy'
    defaultConfig {
        applicationId "amitechnologies.products.apps.equalizeraudioplayer.v3"
        minSdkVersion 17
        targetSdkVersion 25
        versionCode 1
        versionName "1.1"
        signingConfig signingConfigs.config

        // Enabling multidex support.
        multiDexEnabled true
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFile 'D:/AMI_Repo/AMI_Designer/Targets/Android/AMI 3d Player v3/app/proguard-android.txt'
            signingConfig signingConfigs.config
        }
    }
    sourceSets {
        main {
            jniLibs.srcDir 'jniLibs'
        }
    }
    repositories {
        maven { url "https://jitpack.io" }
    }
    dependencies {
        compile fileTree(include: ['*.jar'], dir: 'libs')
        compile 'com.android.support:appcompat-v7:25.3.1'
        compile 'com.google.android.gms:play-services-ads:10.2.4'
        compile 'com.google.apis:google-api-services-youtube:v3-rev180-1.22.0'
        compile 'com.android.support:multidex:1.0.1'
        //glide
        compile 'com.github.bumptech.glide:glide:3.7.0'

        // CardView
        compile 'com.android.support:cardview-v7:25.3.1'
    }
    productFlavors {
    }
}

dependencies {
}

和堆栈跟踪是

Process: amitechnologies.products.apps.equalizeraudioplayer.v3, PID: 15548
                                                                                                       java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{amitechnologies.products.apps.equalizeraudioplayer.v3/amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles}: java.lang.ClassNotFoundException: Didn't find class "amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles" on path: DexPathList[[zip file "/data/app/amitechnologies.products.apps.equalizeraudioplayer.v3-1/base.apk"],nativeLibraryDirectories=[/data/app/amitechnologies.products.apps.equalizeraudioplayer.v3-1/lib/arm, /vendor/lib, /system/lib]]
                                                                                                           at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2395)
                                                                                                           at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2564)
                                                                                                           at android.app.ActivityThread.access0(ActivityThread.java:170)
                                                                                                           at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1441)
                                                                                                           at android.os.Handler.dispatchMessage(Handler.java:111)
                                                                                                           at android.os.Looper.loop(Looper.java:194)
                                                                                                           at android.app.ActivityThread.main(ActivityThread.java:5576)
                                                                                                           at java.lang.reflect.Method.invoke(Native Method)
                                                                                                           at java.lang.reflect.Method.invoke(Method.java:372)
                                                                                                           at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:955)
                                                                                                           at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:750)
                                                                                                        Caused by: java.lang.ClassNotFoundException: Didn't find class "amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles" on path: DexPathList[[zip file "/data/app/amitechnologies.products.apps.equalizeraudioplayer.v3-1/base.apk"],nativeLibraryDirectories=[/data/app/amitechnologies.products.apps.equalizeraudioplayer.v3-1/lib/arm, /vendor/lib, /system/lib]]
                                                                                                           at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
                                                                                                           at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
                                                                                                           at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
                                                                                                           at android.app.Instrumentation.newActivity(Instrumentation.java:1070)
                                                                                                           at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2385)
                                                                                                           at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2564) 
                                                                                                           at android.app.ActivityThread.access0(ActivityThread.java:170) 
                                                                                                           at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1441) 
                                                                                                           at android.os.Handler.dispatchMessage(Handler.java:111) 
                                                                                                           at android.os.Looper.loop(Looper.java:194) 
                                                                                                           at android.app.ActivityThread.main(ActivityThread.java:5576) 
                                                                                                           at java.lang.reflect.Method.invoke(Native Method) 
                                                                                                           at java.lang.reflect.Method.invoke(Method.java:372) 
                                                                                                           at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:955) 
                                                                                                           at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:750) 
                                                                                                        Suppressed: java.lang.ClassNotFoundException: amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles
                                                                                                           at java.lang.Class.classForName(Native Method)
                                                                                                           at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
                                                                                                           at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
                                                                                                           at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
                                                                                                                ... 13 more
                                                                                                        Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available

和文件夹结构：

Answer 1

如果您的 minSDK 版本低于 21，您需要为 multidex 执行以下操作

build.gradle

android {
    defaultConfig {
        ...
        minSdkVersion 15 
        targetSdkVersion 25
        multiDexEnabled true
    }
    ...
}

dependencies {
  compile 'com.android.support:multidex:1.0.1'
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="your_app_package">
    <application
            android:name="android.support.multidex.MultiDexApplication" >
        ...
    </application>
</manifest>

Answer 2

起初"Clean"和"Sync Project with Gradle Files"。然后运行你的代码

Answer 3

As Discussion in chat i found that, Your manual way of generating APK is not generating the correct APK, so i am Suggesting these way to generating APK for Manual Install:

用于调试构建

删除 App 文件夹中的 build 文件夹。
转到 Build>Build APk。它会在你的 app>build>output>apk 目录。
将其复制到您的设备并手动安装。

发布版本

删除 App 文件夹中的 build 文件夹。
转到 Build>Generate Signed APk 并提供推荐的详细信息，确保您的 Build type : release 并检查了签名版本 v1(jar signature) 和 v2(full apk signature) 。它会在你的 app>build>output>apk 目录。
将其复制到您的设备并手动安装。

Answer 4

替换此

<activity
        android:name="amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles"         
</activity>

有了这个

 <activity
        android:name=".amitechnologies.products.apps.equalizeraudioplayer.v3.view.LoaderOfAllMediaFiles"         
 </activity>

原因是您在 android:name

中遗漏了一个点 (.)

Answer 5

删除 app 文件夹中的 Build 文件夹并重建项目

无法实例化 activity 组件信息 Class 未找到异常 Android

Unable to instantiate activity Component Info Class Not found exception Android

java

android

classnotfoundexception