Android Studio - 导入外部库/ Jar [英] Android Studio - Importing external Library/Jar

问题描述

我最近下载了Android Studio来开发Android应用程序（我来自Eclipse），而且我在使用外部库和/或外部JAR文件的同时也遇到了问题。 注意：在Android Studio中从头开始创建的新的应用程序项目进行了以下测试。

示例1：JAR导入。

1. 从Google下载Admobs SDK的新版本。


2. 将库jar 将GoogleAdMobAdsSdk-6.4.1.jar 复制到项目的/ libs /文件夹中。


3. 在项目资源管理器中，右键单击新添加的library.jar，然后单击添加为库。

技术上在这一点上一切都有效，导入工作很好，布局编辑器显示了 AdView 小部件，以及所有这些。 唯一问题是它不会成功编译。

从控制台登录：

  Gradle：
 FAILURE ：构建失败，异常。 
 
 *出了什么问题：
执行失败的任务'：APITests：compilePaidDebug'。 
>汇编失败;有关详细信息，请参阅编译器错误输出。 
 
 *尝试：
使用--stacktrace选项运行以获取堆栈跟踪。使用--info或--debug选项运行以获取更多的日志输出。 
 
无法使用Gradle发行版http://services.gradle.org/distributions/gradle-1.6-bin.zip执行构建。 
  

我尝试运行 gradlew compileDebug --stacktrace ，而且问题似乎是尽管能够在代码和代码中都强制导入这些类。设计编辑，在编译时，无法解析导入。以下是日志的相关部分：（此处的完整堆栈跟踪）

  java：6：错误：com.google.ads包不存在
 import com.google.ads.AdRequest; 
 java：7：错误：com.google.ads包不存在
 import com.google.ads.AdView; 
 java：11：错误：找不到符号
 AdView mAdView; 
符号：类AdView 
位置：class MainActivity 
 java：22：错误：找不到符号
 mAdView =（AdView）this.findViewById（R.id.adView）; 
符号：类AdView 
位置：class MainActivity 
 java：23：错误：找不到符号
 mAdView.loadAd（new AdRequest（））; 
符号：class AdRequest 
位置：class MainActivity 
 5个错误
：测试：compileDebug失败
  

但是，再次，导入在编辑器中工作良好，依赖关系如下：

然后，我尝试编辑build.gradle文件以包含新的lib，如下所示：

 依赖关系{
编译文件（'libs / android-support-v4.jar'，'libs / GoogleAdMobAdsSdk-6.4.1.jar'）
} 
  

这一次，它确实编译成功，但是应用程序现在强制关闭，显然它不能从lib中找到一个特定的类应用程序包。

 导致：java.lang.ClassNotFoundException：没有在路径上找到类com.google.ads.AdView /data/app/com.foo.test-1.apk 
  

任何想法？谢谢！

解决方案

所以，

使用Android Studio 0.1.1将JAR强制导入您的项目：

• 下载library.jar文件并将其复制到/ libs /您的应用程序项目中的文件夹。


• 打开build.gradle文件并编辑您的依赖项以包含新的.jar文件：

编译文件（'libs / android-support-v4.jar'，'libs / GoogleAdMobAdsSdk-6.4.1.jar'）

• 文件 - >关闭项目


• 在项目的根位置打开命令提示符，即'C： \Users\Username\AndroidStudioProjects\MyApplicationProject\'


• 在命令提示符下，键入 gradlew clean ，等待完成。


• 在Android Studio中重新打开您的应用程序项目。


• 测试运行您的应用程序，它应该成功运行。

I recently downloaded Android Studio to develop Android applications (I'm coming from Eclipse), and I am having issues using external libraries and/or external JAR files alongside my own project. NOTE: the following tests were conducted on a new application project created from scratch in Android Studio.

Example 1: JAR Import.

1. Download a fresh copy of the Admobs SDK from Google.
2. Copy the library jar GoogleAdMobAdsSdk-6.4.1.jar to the project's /libs/ folder.
3. In the project explorer, right click on the newly added library.jar and click on 'Add as Library'.

Technically at this point everything works, imports work just fine, the layout editor shows a preview of the AdView widget, and all that. The only problem is that it doesn't compile succesfully.

Log from console:

Gradle: 
FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':APITests:compilePaidDebug'.
> Compilation failed; see the compiler error output for details.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

Could not execute build using Gradle distribution 'http://services.gradle.org/distributions/gradle-1.6-bin.zip'.

I tried running gradlew compileDebug --stacktrace, and the problem seems to be that the despite being able to import the classes sucesfully in both the code & design editor, at compile time, it cannot resolve the imports. Here's the relevant part of the log: (full stacktrace here)

java:6: error: package com.google.ads does not exist
import com.google.ads.AdRequest;    
java:7: error: package com.google.ads does not exist
import com.google.ads.AdView;
java:11: error: cannot find symbol
AdView mAdView;
symbol:   class AdView
location: class MainActivity
java:22: error: cannot find symbol
mAdView = (AdView)this.findViewById(R.id.adView);
symbol:   class AdView
location: class MainActivity
java:23: error: cannot find symbol
mAdView.loadAd(new AdRequest());
symbol:   class AdRequest
location: class MainActivity
5 errors
:Test:compileDebug FAILED

But again, the imports work well in the editor, and the dependency is there:

It's also worth noting that without attempting to add a library/JAR, the projects compiles just fine.

I then tried editing the build.gradle file to include the new lib like this:

dependencies {
compile files('libs/android-support-v4.jar', 'libs/GoogleAdMobAdsSdk-6.4.1.jar')
}

This time, it did compile succesfully, but the app now force closes, as apparently it cannot find a specific class from the lib in the application package.

Caused by: java.lang.ClassNotFoundException: Didn't find class "com.google.ads.AdView" on path: /data/app/com.foo.test-1.apk

Any ideas? Thanks!

解决方案

So,

Steps to follow in order to import a JAR sucesfully to your project using Android Studio 0.1.1:

• Download the library.jar file and copy it to your /libs/ folder inside your application project.
• Open the build.gradle file and edit your dependencies to include the new .jar file:

compile files('libs/android-support-v4.jar', 'libs/GoogleAdMobAdsSdk-6.4.1.jar')

• File -> Close Project
• Open a command prompt on your project's root location, i.e 'C:\Users\Username\AndroidStudioProjects\MyApplicationProject\'
• On the command prompt, type gradlew clean, wait till it's done.
• Reopen your application project in Android Studio.
• Test run your application and it should work succesfully.

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