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我正在看Scala中的步骤6.9中的例子,并且他的设置背景的方法不足,因为当框架被调整大小时,背景不会改变。示例代码(更新更改到2.10版本的工作是:如何在Scala swing中设置背景
import scala.swing._
import scala.swing.event._
object circle extends SimpleSwingApplication {
def top = new MainFrame {
var mouseX = 0
var mouseY = 0
var mouseclicked = false
title = "Draw Circle"
val rect = new java.awt.Rectangle(350,250)
preferredSize = new Dimension(350,250)
val canvas = new Panel {
border = Swing.EmptyBorder(15, 15, 15, 15)
opaque = false
override def paintComponent(g: java.awt.Graphics2D) {
// g.setBackground(java.awt.Color.magenta)
g.setColor(java.awt.Color.magenta)
g.fill(rect)
g.setColor(java.awt.Color.blue)
if (mouseclicked) {
g.fillOval(mouseX-10, mouseY-10, 20, 20)
mouseclicked = false
}
}
listenTo(mouse.clicks)
reactions += {
case MouseClicked(_, p, _, 1, _) => {
mouseX = p.x
mouseY = p.y
mouseclicked = true
repaint
}
}
}
contents = canvas
}
}
我试着用g.setBackground(更换g.setColor(...)和g.fill(矩形)...)为在上面的注释,它编译,但不起作用。
有人建议可以以正确的方式做到这一点?
在此先感谢。