Question

我有这个：

Bike.java

public class Bike {
    String serial;

    @Inject
    Wheels wheels;

    public Bike(String serial) {
        this.serial = serial;
    }
}

BikeModule.java

@Module
public class BikeModule {
    @Provides
    public Bike provideBike() {
        return new Bike("BIK-001");
    }

    @Provides
    public Wheels provideWheels() {
        return new Wheels("WLS-027");
    }
}

BikeComponent.java

@Component(modules = BikeModule.class)
public interface BikeComponent {
    Bike bike();
}

现在问题出现了：当我打电话给BikeComponent.bike()时，我按照预期使用序列号为BIK-001的自行车，但车轮没有注入。但是，如果我使用Bike注释@Inject构造函数并删除BikeModule.provideBike()方法，那么轮子执行会被注入。所以问题似乎是关于注入在@Provides方法中创建的对象，而不是由Dagger本身创建。

有没有办法告诉Dagger注入一个提供的对象？

Answer 1

像这样改写：

public class Bike {

    private final String serial;
    private final Wheels wheels;

    @Inject
    public Bike(String serial, Wheels wheels) {
        this.serial = serial;
        this.wheels = wheels;
    }
}

@Module
public final class BikeModule {

    @Provides
    public static Bike provideBike(Wheels wheels) {
        return new Bike("BIK-001", wheels);
    }

    @Provides
    public static Wheels provideWheels() {
        return new Wheels("WLS-027");
    }
}

Dagger 2：如何注入在@Provides方法中创建的对象？

1 个答案: