我正在尝试使用新的Android Studio,但我似乎不能让它正常工作。

我正在使用Gson库来序列化/反序列化json对象。但是这个库不知何故没有包含在构建中。

我用MainActivity创建了一个新项目。 复制gson-2.2.3.jar到/libs文件夹中,并将其添加为库依赖项(右键单击->添加为库)。这包括android studio中的jar,因此可以从源文件中引用它。

当我尝试运行项目时,它无法编译,所以我添加:

compile files('libs/gson-2.2.3.jar')

到de .gradle文件中的依赖项。之后,它正确编译,但当运行应用程序时,我得到一个ClassDefNotFoundException。

有人知道我哪里做错了吗?


当前回答

下面是将本地jar文件作为库添加到模块的说明:

Create a 'libs' folder in the top level of the module directory (the same directory that contains the 'src' directory) In the build.gradle file add the following so that your dependencies closure has: dependencies { // ... other dependencies compile files('libs/<your jar's name here>') } Android Studio should have already setup a gradlew wrapper. From the command line, navigate to the top level of your project (the directory that has a gradlew file). Run ./gradlew assemble. This should compile the project with the library. You may need to fix errors in your build.gradle file as necessary. In order to have Android Studio recognize the local jar files as libraries for support while coding in the IDE, you need to take a few more steps: 4.1. Right click on the module in the left hand panel and choose Open Library Settings. 4.2. On the left panel of the dialog, choose Libraries. 4.3. Click the + sign above the panel second from the left -> Java 4.4. Select your local jar and add it to the project. You may need to run the above ./gradlew command one more time

其他回答

下面是将本地jar文件作为库添加到模块的说明:

Create a 'libs' folder in the top level of the module directory (the same directory that contains the 'src' directory) In the build.gradle file add the following so that your dependencies closure has: dependencies { // ... other dependencies compile files('libs/<your jar's name here>') } Android Studio should have already setup a gradlew wrapper. From the command line, navigate to the top level of your project (the directory that has a gradlew file). Run ./gradlew assemble. This should compile the project with the library. You may need to fix errors in your build.gradle file as necessary. In order to have Android Studio recognize the local jar files as libraries for support while coding in the IDE, you need to take a few more steps: 4.1. Right click on the module in the left hand panel and choose Open Library Settings. 4.2. On the left panel of the dialog, choose Libraries. 4.3. Click the + sign above the panel second from the left -> Java 4.4. Select your local jar and add it to the project. You may need to run the above ./gradlew command one more time

Easy steps to add external library in Android Studio If you are in Android View in project explorer, change it to Project view as below Right click the desired module where you would like to add the external library, then select New > Directroy and name it as 'libs' Now copy the blah_blah.jar into the 'libs' folder Right click the blah_blah.jar, Then select 'Add as Library..'. This will automatically add and entry in build.gradle as compile files('libs/blah_blah.jar') and sync the gradle. And you are done Please Note : If you are using 3rd party libraries then it is better to use dependencies where Gradle script automatically downloads the JAR and the dependency JAR when gradle script run. Ex : compile 'com.google.android.gms:play-services-ads:9.4.0' Read more about Gradle Dependency Mangement

我只需要在build.gradle中添加一行就可以了:

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar']) ----> AS creates this
    implementation 'com.google.code.gson:gson:2.3.1'   ----------> I added this one
}

不要忘记点击右上角的“立即同步”。

我使用的是Android Studio 1.0.1。

就像许多人之前指出的那样,你应该补充

compile files('libs/gson-2.2.3.jar') 

适合你的身材。gradle文件。

然而,我在Android Studio中有一个项目,是从Eclipse迁移过来的,在这种情况下,“libs”文件夹被命名为“lib”,所以对我来说,删除“s”解决了问题。

下载并复制你的。jar文件到libs文件夹,然后添加这些行到build.gradle:

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.google.code.gson:gson:2.3.1'
}

别忘了按“立即同步”