Dagger 1 不会现场注入 Java class 到 Kotlin activity

Question

我有一个使用 Dagger 1 并用 Java 编写的大项目。我现在正在 Kotlin 中添加新活动，但我无法在 Kotlin Activity.

中注入 Java class

这是我的模块

import dagger.Module;
import dagger.Provides;

@Module(
        injects = {

                HomeActivity.class
        },
        complete = false,
        library = true
)
public class AppModule {

    @Provides
    @ForApplication
    @Singleton
    public SessionStorage provideSessionStorage(@ForApplication YakApplication app) {
        return new SessionStorage(app);
    }
}

这是 SessionStorage :

public class SessionStorage {
private SharedPreferences preferences;
public SessionStorage(Context appContext){
    preferences=appContext.getSharedPreferences(appContext.getPackageName(),Context.MODE_PRIVATE);
}
}

这里是首页Activity：

class HomeActivity : AppCompatActivity(), NavigationBarItemListener {

    override fun onSelectedNavigationBarItem(tag: String) {
        message.text = tag
    }

    @Inject
    @ForApplication
    @JvmField
    var sessionStorage : SessionStorage? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_home)
        BaseApplication.get(this).inject(this)
        bottomBarNavigation.navigationBarItemListener = this
        bottomBarNavigation.navigationBaRContainer.changeBackgroundColor(Color.BLACK)
    }

    override fun onStart() {
        super.onStart()
        bottomBarNavigation.update(sessionStorage?.favoriteTeamId)
    }
}

这是错误：

 2018-10-26 10:30:47.485 29873-29873/com.myproject E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.myproject, PID: 29873
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myproject.home.HomeActivity}: java.lang.IllegalStateException: Errors creating object graph:
      com.myproject.SessionStorage has no injectable members. Do you want to add an injectable constructor? required by class com.myproject.home.HomeActivity
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
        at android.app.ActivityThread.-wrap12(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:154)
        at android.app.ActivityThread.main(ActivityThread.java:6119)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
     Caused by: java.lang.IllegalStateException: Errors creating object graph:
      com.myproject.SessionStorage has no injectable members. Do you want to add an injectable constructor? required by class com.myproject.home.HomeActivity
        at dagger.internal.ThrowingErrorHandler.handleErrors(ThrowingErrorHandler.java:34)
        at dagger.internal.Linker.linkRequested(Linker.java:182)
        at dagger.ObjectGraph$DaggerObjectGraph.getInjectableTypeBinding(ObjectGraph.java:309)
        at dagger.ObjectGraph$DaggerObjectGraph.inject(ObjectGraph.java:279)
        at com.myproject.BaseApplication.inject(BaseApplication.java:239)
        at com.myproject.home.HomeActivity.onCreate(HomeActivity.kt:34)
        at android.app.Activity.performCreate(Activity.java:6679)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
        ... 9 more

我不明白为什么不应该注入SessionStorage。到目前为止我发现的唯一解决方法是将 HomeActivity 扩展到 JavaActivity 并在那里注入 SessionStorage。但我认为这不是最好的解决方案

Answer 1

您是否将这两行添加到您的 Gradle 插件中？

apply plugin: 'kotlin-kapt'
....
kapt 'com.google.dagger:dagger-compiler:2.5'

我猜你忘了将 Kotlin 注释处理器添加到你的 gradle

编辑

同时检查这个 link。 Dagger - class has no injectable members

Answer 2

我终于解决了这个问题。我正在添加我的解决方案，也许其他人也会遇到同样的问题。

Gradle 文件

apply plugin: 'kotlin-kapt'
android{
  kapt {
        generateStubs = true
    }
}
dependencies {
    //Dagger
    kapt 'com.squareup.dagger:dagger-compiler:1.2.2'
}

这就是我注射 java class 的方式：

 @Inject
 @field:ForApplication
 lateinit var sessionStorage: SessionStorage

显然需要指定的注释有字段。我发现这个 link 很有用 https://github.com/google/dagger/issues/900

Dagger 1 不会现场注入 Java class 到 Kotlin activity

Dagger 1 won't field inject Java class into Kotlin activity

java

android

kotlin

dagger