Groovy的android系统 - 发射活动不能找到 [英] Groovy in android - launcher activity cant be found

问题描述

我试图运行一个简单的Andr​​oid程序。问题是发射活动是一个常规的文件，这就是所谓的MainActivity.groovy，它驻留在java源文件夹中。这是我的依赖的gradle和项目结构的照片：

i'm trying to run a simple android program. The issue is the launcher activity is a groovy file, it's called MainActivity.groovy and it resides in the java source folder. Here is a photo of my gradle dependencies and project structure:

和这里是Android清单文件：

and here is the android manifest file:

<?xml version="1.0" encoding="utf-8"?>

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

和最后这里是错误，当我运行程序：

and lastly here is the error when i run the program:

07-08 17:11:49.297  20173-20173/com.example.uen229.myrxjavaandroidproject2 E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.uen229.myrxjavaandroidproject2, PID: 20173
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.uen229.myrxjavaandroidproject2/com.example.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.example.MainActivity" on path: DexPathList[[zip file "/data/app/com.example.uen229.myrxjavaandroidproject2-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2209)
        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)
 Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.MainActivity" on path: DexPathList[[zip file "/data/app/com.example.uen229.myrxjavaandroidproject2-1/base.apk"],nativeLibraryDirectories=[/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:1065)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2199)
            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)
Suppressed: java.lang.ClassNotFoundException: com.example.MainActivity
        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

我试图重新启动我的电脑和IDE。请记住，在MainActivity已更名为MainActivity.groovy。我究竟做错了什么？

i have tried restarting my pc and IDE. Keep in mind the MainActivity has been renamed to MainActivity.groovy. What am i doing wrong ?

更新：下面的说明后这里

我做了我的目录结构看起来像它解决了问题如下：

i made my directory structure looked like the following which resolved the issue:

推荐答案

在您的code你有很多问题：

In your code you have many problems:

• Groovy文件应该是在常规文件夹，而不是的Java


• Android不支持常规作为母语，只是Java，所以你需要pre-编译Groovy文件为了让在Dalvik / ART执行它。这样做的方式是在申请做这个工作对你的build.gradle插件。

• Groovy files should be under groovy folder, not java
• Android does not support groovy as a native language, just java, so you need to pre-compile the groovy files in order to let the Dalvik/ART execute it. The way to do so is applying a plugin in the build.gradle that does this work for you.

这是在github插件一个伟大的教程。

This is a great tutorial for the plugin on github.

这篇关于Groovy的android系统 - 发射活动不能找到的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！