Scala MouseEvent - 如何知道按下了哪个按钮? [英] Scala MouseEvent - How to know which button was pressed?

问题描述

我正在使用 Scala Swing 编写一个 Scala 应用程序.我可以监听 MouseClicked 以在鼠标被点击时得到通知，但我怎么知道按下了哪个按钮.文档很糟糕，所以我查看了 MouseEvent 的 Java 文档，它说可以从修饰符字段中检索键，所以我尝试输出 scala MouseClicked 事件，结果是一个整数，0 表示左键单击，鼠标按钮 3 和鼠标按钮 4 以及 256 表示右键单击.

I'm writing a scala application using scala swing. I can listen for MouseClicked to get notified whenever the mouse is clicked, but how do i know which button was pressed. The documentation is pretty bad, so i have looked in the Java documentation for MouseEvent, which says that the key can be retrieved from the modifiers field, so i tried to output the modifiers field of the scala MouseClicked event, which turned out to be an integer, 0 for left click, mouse button 3 and mouse button 4 and 256 for right click.

如果我只需要知道左键单击和右键单击之间的区别，它看起来会起作用，但是我可以确定所有修饰符都以这种方式起作用吗?文档什么也没说，据我所知，修改器可能会受到其他因素的影响，而不仅仅是按下了哪个鼠标按钮.我还想知道左键单击和鼠标按钮 3 和 4 之间的区别.我认为用户不希望它们做与左键单击相同的事情.

It looks like it will work if i only need to know the difference between left and right click, but can i be sure the modifiers all ways work this way? The documentation says nothing, and for what i know modifiers could be affected by other things than just which mouse button was pressed. I would also like to know the difference between left click and mouse button 3 and 4. I don't think users expect them to do the same thing as left click.

scala 文档中有一个 MouseButtonEvent，它可以用于任何事情吗?文档没有说明它的作用.

In the scala documentation there is a MouseButtonEvent, can this be used for anything? The documentation says nothing about what it does.

推荐答案

您始终可以使用 x.peer.getButton 来获取 Java 映射(其中 x 是您的Scala MouseClicked 事件).peer 几乎总是包含与 Scala 类等价的 Java——在这种情况下确实如此.

You can always use x.peer.getButton to get the Java mapping (where x is your Scala MouseClicked event). peer almost always contains a Java equivalent to the Scala class--and it does in this case.

这篇关于Scala MouseEvent - 如何知道按下了哪个按钮?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！