MainActivity 的 Android API 26 上的 ClassNotFoundException（使用 API 30）
ClassNotFoundException on Android API 26 for MainActivity (working with API 30)
我有一个 Android Studio 项目，我在 API 30 上测试过它并且工作正常。现在我在 API 26（这是我为项目设置的最低 SDK 版本）上尝试 运行 它，但我无法启动该应用程序。
两次我都使用了模拟的 Pixel 3a 和一个外部设备。
错误日志：
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.main.xyz, PID: 9389
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.main.xyz/com.main.xyz.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.main.xyz.MainActivity" on path: DexPathList[[zip file "/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/lib/x86, /system/lib, /vendor/lib]]
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2718)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.main.xyz.MainActivity" on path: DexPathList[[zip file "/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/lib/x86, /system/lib, /vendor/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:93)
at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at android.app.Instrumentation.newActivity(Instrumentation.java:1173)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2708)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Suppressed: java.io.IOException: Failed to open dex files from /data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk because: Failure to verify dex file '/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk': Bad method handle type 7
at dalvik.system.DexFile.openDexFileNative(Native Method)
at dalvik.system.DexFile.openDexFile(DexFile.java:353)
at dalvik.system.DexFile.<init>(DexFile.java:100)
at dalvik.system.DexFile.<init>(DexFile.java:74)
at dalvik.system.DexPathList.loadDexFile(DexPathList.java:374)
at dalvik.system.DexPathList.makeDexElements(DexPathList.java:337)
at dalvik.system.DexPathList.<init>(DexPathList.java:157)
at dalvik.system.BaseDexClassLoader.<init>(BaseDexClassLoader.java:65)
at dalvik.system.PathClassLoader.<init>(PathClassLoader.java:64)
at com.android.internal.os.PathClassLoaderFactory.createClassLoader(PathClassLoaderFactory.java:43)
at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:69)
at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:36)
at android.app.LoadedApk.createOrUpdateClassLoaderLocked(LoadedApk.java:676)
at android.app.LoadedApk.getClassLoader(LoadedApk.java:709)
at android.app.LoadedApk.getResources(LoadedApk.java:936)
at android.app.ContextImpl.createAppContext(ContextImpl.java:2242)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5672)
at android.app.ActivityThread.-wrap1(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1661)
... 6 more
我的MainActivity.java:
public class MainActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
//Called by Button
public void login(View v) {
Intent intent = new Intent(MainActivity.this, Uebersicht.class);
startActivity(intent)
}
我的build.gradle（应用程序）：
apply plugin: 'com.android.application'
android {
compileSdkVersion 30
buildToolsVersion "30.0.0"
defaultConfig {
applicationId "com.main.xyz"
minSdkVersion 26
targetSdkVersion 30
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
proguardFiles 'proguard-rules.pro'
}
buildTypes {
release {
minifyEnabled true
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: "libs", include: ["*.jar"])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.android.material:material:1.1.0'
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.google.android.gms:play-services-vision:20.1.0'
}
我的build.grade（项目）：
buildscript {
repositories {
google()
jcenter()
}
dependencies {
classpath "com.android.tools.build:gradle:4.0.0"
}
}
allprojects {
repositories {
google()
jcenter()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
还有我的 manifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.main.xyz">
<uses-permission android:name="android.permission.CAMERA" />
<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"
android:usesCleartextTraffic="true">
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Uebersicht"
android:label="" />
<activity
android:name=".ProductActivity"
android:label="" />
<activity
android:name=".AddActivity"
android:label=""/>
<activity
android:name=".ScanActivity"
android:label="" />
</application>
</manifest>
我一直在寻找解决方案。由于我是 Android 的新手，非常感谢所有帮助。如果你能提供它，我真的很想对我的问题进行解释以及能够理解这里出了什么问题的解决方案。
我猜这是 dexing 的问题，所以尝试将这个库添加到你的依赖项中 gradle，按照以下步骤操作：
dependencies {
implementation fileTree(dir: "libs", include: ["*.jar"])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.android.material:material:1.1.0'
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.google.android.gms:play-services-vision:20.1.0'
implementation 'com.android.support:multidex:1.0.3' // add this library
}
并在此处添加此代码
android {
compileSdkVersion 30
buildToolsVersion "30.0.0"
defaultConfig {
applicationId "com.main.xyz"
minSdkVersion 26
targetSdkVersion 30
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
proguardFiles 'proguard-rules.pro'
multiDexEnabled true // add this line of code
}
我查看了 dexing 错误描述并找到了 。实施
compileOptions {
coreLibraryDesugaringEnabled true
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
和
coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:1.0.9'
进入应用程序的 build.gradle 文件解决了问题。
我有一个 Android Studio 项目，我在 API 30 上测试过它并且工作正常。现在我在 API 26（这是我为项目设置的最低 SDK 版本）上尝试 运行 它，但我无法启动该应用程序。 两次我都使用了模拟的 Pixel 3a 和一个外部设备。
错误日志：
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.main.xyz, PID: 9389
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.main.xyz/com.main.xyz.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.main.xyz.MainActivity" on path: DexPathList[[zip file "/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/lib/x86, /system/lib, /vendor/lib]]
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2718)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.main.xyz.MainActivity" on path: DexPathList[[zip file "/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/lib/x86, /system/lib, /vendor/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:93)
at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at android.app.Instrumentation.newActivity(Instrumentation.java:1173)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2708)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Suppressed: java.io.IOException: Failed to open dex files from /data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk because: Failure to verify dex file '/data/app/com.main.xyz-rZkYLBaLo3gdkb7oCChonQ==/base.apk': Bad method handle type 7
at dalvik.system.DexFile.openDexFileNative(Native Method)
at dalvik.system.DexFile.openDexFile(DexFile.java:353)
at dalvik.system.DexFile.<init>(DexFile.java:100)
at dalvik.system.DexFile.<init>(DexFile.java:74)
at dalvik.system.DexPathList.loadDexFile(DexPathList.java:374)
at dalvik.system.DexPathList.makeDexElements(DexPathList.java:337)
at dalvik.system.DexPathList.<init>(DexPathList.java:157)
at dalvik.system.BaseDexClassLoader.<init>(BaseDexClassLoader.java:65)
at dalvik.system.PathClassLoader.<init>(PathClassLoader.java:64)
at com.android.internal.os.PathClassLoaderFactory.createClassLoader(PathClassLoaderFactory.java:43)
at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:69)
at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:36)
at android.app.LoadedApk.createOrUpdateClassLoaderLocked(LoadedApk.java:676)
at android.app.LoadedApk.getClassLoader(LoadedApk.java:709)
at android.app.LoadedApk.getResources(LoadedApk.java:936)
at android.app.ContextImpl.createAppContext(ContextImpl.java:2242)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5672)
at android.app.ActivityThread.-wrap1(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1661)
... 6 more
我的MainActivity.java:
public class MainActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
//Called by Button
public void login(View v) {
Intent intent = new Intent(MainActivity.this, Uebersicht.class);
startActivity(intent)
}
我的build.gradle（应用程序）：
apply plugin: 'com.android.application'
android {
compileSdkVersion 30
buildToolsVersion "30.0.0"
defaultConfig {
applicationId "com.main.xyz"
minSdkVersion 26
targetSdkVersion 30
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
proguardFiles 'proguard-rules.pro'
}
buildTypes {
release {
minifyEnabled true
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: "libs", include: ["*.jar"])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.android.material:material:1.1.0'
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.google.android.gms:play-services-vision:20.1.0'
}
我的build.grade（项目）：
buildscript {
repositories {
google()
jcenter()
}
dependencies {
classpath "com.android.tools.build:gradle:4.0.0"
}
}
allprojects {
repositories {
google()
jcenter()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
还有我的 manifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.main.xyz">
<uses-permission android:name="android.permission.CAMERA" />
<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"
android:usesCleartextTraffic="true">
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Uebersicht"
android:label="" />
<activity
android:name=".ProductActivity"
android:label="" />
<activity
android:name=".AddActivity"
android:label=""/>
<activity
android:name=".ScanActivity"
android:label="" />
</application>
</manifest>
我一直在寻找解决方案。由于我是 Android 的新手，非常感谢所有帮助。如果你能提供它，我真的很想对我的问题进行解释以及能够理解这里出了什么问题的解决方案。
我猜这是 dexing 的问题，所以尝试将这个库添加到你的依赖项中 gradle，按照以下步骤操作：
dependencies {
implementation fileTree(dir: "libs", include: ["*.jar"])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.android.material:material:1.1.0'
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.google.android.gms:play-services-vision:20.1.0'
implementation 'com.android.support:multidex:1.0.3' // add this library
}
并在此处添加此代码
android {
compileSdkVersion 30
buildToolsVersion "30.0.0"
defaultConfig {
applicationId "com.main.xyz"
minSdkVersion 26
targetSdkVersion 30
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
proguardFiles 'proguard-rules.pro'
multiDexEnabled true // add this line of code
}
我查看了 dexing 错误描述并找到了
compileOptions {
coreLibraryDesugaringEnabled true
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
和
coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:1.0.9'
进入应用程序的 build.gradle 文件解决了问题。