Java ActionEvent e 是什么意思？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/31216051/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
What does ActionEvent e mean?
提问by MooseMan55
I am learning Java and would really like to have a deeper understanding of what the ActionEvent e perameter means and stands for. When I code I don't just want to spit out lines that work, but I don't understand. I want to have a full understanding of concepts before I use them.
我正在学习 Java，并且真的很想更深入地了解 ActionEvent e 参数的含义和代表的含义。当我编码时，我不只是想吐出有效的行，但我不明白。我想在使用它们之前对概念有一个完整的理解。
So what specifically is it asking for and what do the two parts(ActionEvent and e) mean?
那么它的具体要求是什么，两部分（ActionEvent 和 e）是什么意思？
class ButtonListener implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
}
}
Thanks.
谢谢。
采纳答案by Eric Guan
ActionEventis a class, eis an instance of that class. You can use e to call it's methods/properties, found here
ActionEvent是一个类，e是该类的一个实例。您可以使用 e 来调用它的方法/属性，在此处找到
http://docs.oracle.com/javase/7/docs/api/java/awt/event/ActionEvent.html
http://docs.oracle.com/javase/7/docs/api/java/awt/event/ActionEvent.html
ActionEventis just a type, it informs you what type of object eis. By the way, you can change eto whatever you prefer, for ex. eventor object.
ActionEvent只是一种类型，它会告诉您对象e是什么类型。顺便说一句，您可以更改e为您喜欢的任何内容，例如。event或object。
ActionEvent event, ActionEvent object(remember, not to be confused with Object, its object with lower case "o"), ActionEvent anyVariableNameetc...
ActionEvent event, ActionEvent object（请记住，不要与Object带有小写“o”的对象混淆）ActionEvent anyVariableName等...
Then inside actionPerformed()you can call stuff like event.doSomething();
然后在里面actionPerformed()你可以调用类似的东西event.doSomething();
回答by InsidiarumCrassescit
The ActionEventis an "event" that your listener catches, as sent by a dispatcher. This mean, in layman's terms, that some thread somewhere has decided that your actions (i.e. clicking a button, etc.) have caused an action to occur, and informs the System. Your listener picks up on this, and takes a reference as the parameter e. Thismay help to shed a bit more light on what/why the action is; and, it may be beneficial to check out the Event Dispatch Thread (EDT).
这ActionEvent是您的侦听器捕获的“事件”，由调度程序发送。这意味着，用外行人的话说，某处的某个线程已决定您的操作（即单击按钮等）导致了某个操作的发生，并通知系统。您的听众会注意到这一点，并将参考作为参数e。这可能有助于更清楚地了解行动是什么/为什么；并且，查看事件调度线程 ( EDT)可能会有所帮助。
回答by Fayaz
This should help you: http://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html
这应该可以帮助您：http: //docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html
Basically,ButtonListener is your ActionListener Implementation. You will use it like
基本上，ButtonListener 是您的 ActionListener 实现。你会像这样使用它
someButton1.addActionListener(new ButtonListener());
someButton2.addActionListener(new ButtonListener());
It will listen for any action events on the buttons 'someButton1' and 'someButton2'.But we might want to handle clicks on both buttons in a different way. Thats when ActionEvent is of use.
它将侦听按钮“someButton1”和“someButton2”上的任何动作事件。但我们可能希望以不同的方式处理这两个按钮上的点击。那就是使用 ActionEvent 的时候。
Inside method,we can do this by following
内部方法，我们可以通过以下方式做到这一点
@Override
public void actionPerformed(ActionEvent e){
if(e.getActionCommand().equals("Button 1")){
//Process Button 1 action event here
}
else if(e.getActionCommand().equals("Button 2")){
//Process Button 2 action event here
}
}
