ClassNotFoundException:没有找到类"android.databinding.DataBinderMapper"

Question

我正在使用android的数据绑定库来查看库项目中的视图

我在根gradle文件中添加了以下行

classpath 'com.android.databinding:dataBinder:1.0-rc1'

并在模块的gradle文件中启用了dataBinding,如下所示

apply plugin: 'com.android.databinding'
...
...
android {
....
  dataBinding {
      enabled = true
  }
}

我已经在我的库项目中以及使用此库的主机应用程序中启用了multiDex但是在启动库的活动时我得到了这个堆栈的错误跟踪

java.lang.NoClassDefFoundError: Failed resolution of: Landroid/databinding/DataBinderMapper;
    at android.databinding.DataBindingUtil.<clinit>(DataBindingUtil.java:31)
    at sdk.ui.activities.MyActivity.onCreate(MyActivity.java:76)
    at android.app.Activity.performCreate(Activity.java:6280)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1116)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2534)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2647)
    at android.app.ActivityThread.-wrap11(ActivityThread.java)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1502)
    at android.os.Handler.dispatchMessage(Handler.java:111)
    at android.os.Looper.loop(Looper.java:207)
    at android.app.ActivityThread.main(ActivityThread.java:5763)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:888)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:749)
Caused by: java.lang.ClassNotFoundException: Didn't find class "android.databinding.DataBinderMapper" on path: DexPathList[[zip file "/data/app/testApp.dev-1/base.apk"],nativeLibraryDirectories=[/data/app/testApp.dev-1/lib/arm64, /data/app/testApp.dev-1/base.apk!/lib/arm64-v8a, /vendor/lib64, /system/lib64]]
    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.databinding.DataBindingUtil.<clinit>(DataBindingUtil.java:31) 
    at sdk.ui.activities.MyActivity.onCreate(MyActivity.java:76) 
    at android.app.Activity.performCreate(Activity.java:6280) 
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1116) 
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2534) 
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2647) 
    at android.app.ActivityThread.-wrap11(ActivityThread.java) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1502) 
    at android.os.Handler.dispatchMessage(Handler.java:111) 
    at android.os.Looper.loop(Looper.java:207) 
    at android.app.ActivityThread.main(ActivityThread.java:5763) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:888) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:749) 
Suppressed: java.lang.ClassNotFoundException: android.databinding.DataBinderMapper
    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)
        ... 15 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available

Answer 1

确保所有使用DataBinding的模块都启用了它.这就是我得到这个例外的原因.

android {
    ....
    dataBinding {
        enabled = true
    }
}

Answer 2

终于，我能够解决这个问题。似乎该应用程序的apt版本与库模块之间存在冲突。

将应用程序中的apt版本升级到

classpath 'com.neenbedankt.gradle.plugins:android-apt:1.8'

Answer 3

除了将以下内容添加到build.gradle：

android {
    dataBinding {
        enabled = true
    }
}

我还必须添加以下依赖项：

dependencies {
    kapt 'com.android.databinding:compiler:3.0.1'
}