Java

Question

我有一个 service 有一个 interface，我是 implementing 多个 activities 中的 interface callback，但因为我在每个 activity's onCreate 上调用应用程序 instance，interfaces 仅在当前 activity 上响应。我如何确保它们在每个 activity.

中一起工作

MyApp.java

public class MyApp extends Application {

    private static MyApp myApp;

    @Override
    public void onCreate() {
        super.onCreate();
        myApp = new MyApp();
    }

    @Contract(pure = true)
    public static synchronized MyApp getInstance() {
        MyApp myApp;
        synchronized (MyApp.class) {
            myApp = MyApp.myApp;
        }
        return myApp;
    }

    public void setCallBackListener(MyService.ReceiversCallbacks receiversCallbacks) {
        MyService.receiversCallbacks = receiversCallbacks;
    }
}

MyService.java

public class MyService extends Service {

    public static MyService.ReceiversCallbacks receiversCallbacks;

    public MyService() {
        super();
    }

    public interface ReceiversCallbacks {
        void onReceiveCallbacks(String data);
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Notification notification = new NotificationCompat.Builder(this, NOTIFICATION_ID)
                .setContentTitle("Background service")
                .setSmallIcon(R.drawable.ic_launcher)
                .build();
        startForeground(1, notification);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if (MY_LOGIC) receiversCallbacks.onReceiveCallbacks("DATA_FROM_MY_LOGIC");

        //stopSelf();
        return START_NOT_STICKY;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
    }

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}

ActivityA.java

public class ActivityA extends AppCompatActivity implements MyService.ReceiversCallbacks {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
         MyApp.getInstance().setCallBackListener(this);
    }

    @Override
    public void onReceiveCallbacks(String data) {
           // calling important functions
    }
}

ActivityB.java

public class ActivityB extends AppCompatActivity implements MyService.ReceiversCallbacks {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
         MyApp.getInstance().setCallBackListener(this);
    }

    @Override
    public void onReceiveCallbacks(String data) {
           // calling important functions
    }
}

每个 activity 的 onCreate 当我这样做时 MyApp.getInstance().setCallBackListener(this); 回调的焦点转移到新的 activity。但是我想同时专注于两项或多项活动，我该怎么做？我想要的解决方案有没有更好的方法？

请注意这些：

我不想调用那些函数onResume
我不想使用 Broadcasts

Answer 1

我刚刚为每个 activity 创建了不同的接口并将它们注册到它们对应的 activity，它们成功了！

MyApp.getInstance().setCallBackListener(this);

Java - 接口 - 如何在多个活动中一起分配特定接口

Java - Interface - How do I assign a specific interface in multiple activities all together

android

interface

callback