android - 创建非最终非静态类时出现NoClassDefFoundError

Question

当尝试使用Andriod-SocialButtons项目(https://github.com/championswimmer/Android-SocialButtons)中的代码时，出现以下异常:

I/art: Rejecting re-init on previously-failed class java.lang.Class<in.championswimmer.libsocialbuttons.BtnSocial>
java.lang.NoClassDefFoundError: in.championswimmer.libsocialbuttons.BtnSocial
    at java.lang.Class.classForName(Native Method)
    at java.lang.Class.forName(Class.java:308)
    at java.lang.Class.forName(Class.java:272)
    at XXX.onCreate(XXXActivity.java:76)
    at android.app.Activity.performCreate(Activity.java:5937)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
    at android.app.ActivityThread.access$800(ActivityThread.java:144)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:135)
    at android.app.ActivityThread.main(ActivityThread.java:5221)
    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:899)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

这是我的代码段:

Class c;
c = in.championswimmer.libsocialbuttons.Utils.class;
c = in.championswimmer.libsocialbuttons.BuildConfig.class;
c = in.championswimmer.libsocialbuttons.BtnSocial.class;
c = in.championswimmer.libsocialbuttons.SocialFab.class;

此代码段中的前3行执行正常，但我尝试访问BtnSocial或SocialFab类，该类抛出NoClassDefFoundError。

可能与BtnSocial和SocialFab类不包含任何静态或最终字段或方法有关。

我正在使用Android Studio开发和运行我的应用程序

这是我的项目 build.gradle:

buildscript {
    repositories {
        jcenter()
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.1'
    }
}

allprojects {
    repositories {
        jcenter()
        google()
    }
}

和我的应用程序的build.gradle:

buildscript {
    repositories {
        maven { url 'https://maven.fabric.io/public' }
    }

    dependencies {
        classpath 'io.fabric.tools:gradle:1.22.0'
    }
}
apply plugin: 'com.android.application'
apply plugin: 'io.fabric'

repositories {
    maven { url 'https://maven.fabric.io/public' }
    maven { url "https://jitpack.io" }
}

android {
    ...
    compileSdkVersion 25
    buildToolsVersion "26.0.2"
    defaultConfig {
        applicationId "XXX"
        minSdkVersion 16
        targetSdkVersion 23
        versionCode 9
        versionName "2.4"
        useLibrary 'org.apache.http.legacy'
    }
    buildTypes {
        ...
    }
}

dependencies {
    ...
    compile 'com.android.support:support-v4:25.0.1'
    compile 'com.google.code.gson:gson:1.7.1'
    compile 'com.google.android.gms:play-services-auth:11.8.0'
    compile 'com.github.championswimmer:Android-SocialButtons:1.5.0'
    ...
}

我正完全遵循Android-SocialButtons的文档: https://github.com/championswimmer/Android-SocialButtons/blob/master/README.md。我在做什么错？

Answer 1

您必须在项目级别的构建文件(而不是应用程序级别)中添加jitpack
将您的项目build.gradle更新为

allprojects {
    repositories {
        jcenter()
        google()
        maven { url "https://jitpack.io" }
    }
}