Question

I m implementing IPC via Handlers in an Android application. In the official documentation (here http://developer.android.com/reference/android/app/Service.html) there s an example:

class IncomingHandler extends Handler {
    @Override
    public void handleMessage(Message msg) {
        switch (msg.what) {
            case MSG_REGISTER_CLIENT:
                mClients.add(msg.replyTo);
                break;
            case MSG_UNREGISTER_CLIENT:
                mClients.remove(msg.replyTo);
                break;
            case MSG_SET_VALUE:
                mValue = msg.arg1;
                for (int i=mClients.size()-1; i>=0; i--) {
                    try {
                        mClients.get(i).send(Message.obtain(null,
                                MSG_SET_VALUE, mValue, 0));
                    } catch (RemoteException e) {
                        // The client is dead.  Remove it from the list;
                        // we are going through the list from back to front
                        // so this is safe to do inside the loop.
                        mClients.remove(i);
                    }
                }
                break;
            default:
                super.handleMessage(msg);
        }
    }
}

我的问题是简单明了的:这一行文是什么?

super.handleMessage(msg);

我不得不说这种方法吗?

EDIT: I know that this will call the parent s implementation of that method. But what s in that method? Is there something special that have to be done prior the release of the message?

预收

Answer 1

显示,这一方法的超级类别实施没有任何意义。不过,我要说的是,未来版本的安康可能不同。

Answer 2

它要求在<代码>Handler上实施<代码>handleMessage, 父亲为 加入Handler。

查阅。

关于你的新问题,不应存在任何问题,因为这种方法在<代码>Handler类别中是空的。

Answer 3

我审视了海底来源,只是显示。

/**
 * Subclasses must implement this to receive messages.
 */
public void handleMessage(Message msg) {
}

因此,我不说。

But (as devconsole astutely observed while I was typing my answer), it would be good practice to call it anyway.

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