java中的事件处理，一个vb.net专家 [英] Event handling in java, for a vb.net expert

问题描述

我发现了大量关于处理现有java类的事件的帖子，但是没有关于从头开始创建一个类的事件。_
这个vb.net代码段的java的翻译是什么？ p>

I found tons of posts about handling events of existing java classes, but nothing about creating a class with events from scratch.
What is the translation to java of this vb.net snippet?

Public Class TestClass
    Event TestEvent()
    Sub TestFunction()
        RaiseEvent TestEvent()
    End Sub
End Class
Public Class Form1
    Dim WithEvents TC As New TestClass
    Sub OnTestEvent() Handles TC.TestEvent
    End Sub
End Class

谢谢。

推荐答案

这是Java事件模型背后的理论的一个很好的链接：

Here's a good link on the "theory" behind the Java event model:

• http://docs.oracle.com/javase/1.4 .2 / docs / guide / awt / 1.3 / designspec / events.html

• http://docs.oracle.com/javase/1.4.2/docs/guide/awt/1.3/designspec/events.html

这里是一个链接，说明如何创建自己的，定制的事件：

And here's a link illustrating how to create your own, custom events:

• http://castever.wordpress.com/2008/07/31/how-to-create-your-own-events-in-java /

• http://castever.wordpress.com/2008/07/31/how-to-create-your-own-events-in-java/

这里是一个非常好的例子，从 SO ：

And here's a really good example from SO:

// REFERENCE: https://stackoverflow.com/questions/6270132/create-a-custom-event-in-java
import java.util.*;

interface HelloListener {
    public void someoneSaidHello();
}


class Initiater {
    List<HelloListener> listeners = new ArrayList<HelloListener>();

    public void addListener(HelloListener toAdd) {
        listeners.add(toAdd);
    }

    public void sayHello() {
        System.out.println("Hello!!");

        // Notify everybody that may be interested.
        for (HelloListener hl : listeners)
            hl.someoneSaidHello();
    }
}


class Responder implements HelloListener {
    @Override
    public void someoneSaidHello() {
        System.out.println("Hello there...");
    }
}


class Test {
    public static void main(String[] args) {
        Initiater initiater = new Initiater();
        Responder responder = new Responder();

        initiater.addListener(responder);

        initiater.sayHello();
    }
}

关键是：

1）创建一个定义事件（例如AWT事件模型中的事件）的界面

1) create an "interface" that defines your "event" (such as the events in the AWT event model)

2）创建一个实现这个事件的类（类似于C语言中的回调，实际上是VB使用事件类型自动执行的）。

2) create a class that "implements" this event (analogous to "callbacks" in languages like C - and effectively what VB does for you automagically with the "Event" type).

希望有帮助...至少有一点！

'Hope that helps ... at least a little bit!

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