如何在Android Studio的Java库模块中使用Dagger? [英] How to use Dagger in Java library module in Android Studio?

问题描述

我正在Android Studio项目的Java库模块中使用Dagger，这是我为该模块的 build.gradle 的样子:

I'm using Dagger in a Java library module in an Android Studio project and here's what my build.gradle for the module looks like:

apply plugin: 'java-library'

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation 'com.google.dagger:dagger:2.24'
    annotationProcessor 'com.google.dagger:dagger-compiler:2.24'
}

sourceCompatibility = "7"
targetCompatibility = "7"

我可以看到Dagger正在正确生成实现，并且它们存在于 build/generated/sources/annotationProcessor 中，但是由于某些原因，我无法在代码中访问它们.另外，生成的文件在 package 语句中显示一条错误，指出:

I can see that the Dagger is properly generating implementations and they are present in build/generated/sources/annotationProcessor but for some reason I cannot access them in the code. Also, the generated files shows an error at the package statement that states:

包名称"com.example.javamodule"与文件路径"java.main.com.example.javamodule"不对应

Package name "com.example.javamodule" does not correspond to the file path "java.main.com.example.javamodule"

我在这里有两个问题.首先，如何在我的Java模块代码中访问Dagger生成的类，其次，如何从生成的类中删除上述错误?

I have two questions here. First, how can I access the Dagger generated classes in my java module code and second, how to remove the above-mentioned error from the generated classes?

推荐答案

在您的Java库的gradle文件中:

In your java library's gradle file:

plugins {
    id 'java-library'
    id 'kotlin'
    id 'kotlin-kapt'
}

java {
    sourceCompatibility = JavaVersion.VERSION_1_7
    targetCompatibility = JavaVersion.VERSION_1_7
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"

    //Dependency injection
    implementation 'com.google.dagger:dagger:2.27'
    kapt 'com.google.dagger:dagger-compiler:2.24'
}

然后创建一个类及其依赖项:

Then create a class and its dependencies:

class First
@Inject
constructor(
    private val second: Second,
    private val third: Third
) {
    fun firstFunction() {
        print(second.secondMessage())
        print(third.name)
    }
}

class Second(
    private val name: String
) {
    fun secondMessage(): String {
        return name
    }
}

class Third(
    val name: String
)

然后创建您的匕首模块:

Then create your dagger module:

@Module
class ModuleUtil {

    @Provides
    fun providesSecond(): Second {
        return Second("second")
    }

    @Provides
    fun providesThird(): Third {
        return Third("third")
    }

}

然后创建您的匕首组件:

Then create your dagger component:

@Singleton
@Component(modules = [
    ModuleUtil::class
])
interface MainComponent {

    fun maker(): First

}

用于处理生成的组件的对象:

An object to handle the generated component:

object DaggerWrapper {

    lateinit var mainComponent: MainComponent

    fun initComponent() {
        mainComponent = DaggerMainComponent
            .builder()
            .build()
    }

}

最后在您的应用android模块中(例如，在Activity中):

And finally in your app android module(eg. inside an Activity):

DaggerWrapper.initComponent()
            val mainComponent = DaggerWrapper.mainComponent
            val first = mainComponent.maker()
            first.firstFunction()

这篇关于如何在Android Studio的Java库模块中使用Dagger?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！