Groovy SwingBuilder：更改面板颜色的按钮

Question

为什么这段代码会失败？ 我想更改动态构建的一系列多个面板中的一个面板的颜色（面板总数事先未知）。

由于某种原因，此代码在引用特定面板的名称（例如“panel2”）时有效，但在我动态引用它（“panelID”）时则无效。

import groovy.swing.SwingBuilder
import javax.swing.WindowConstants as WC
import javax.swing.JOptionPane
import javax.swing.BoxLayout as BXL

swing = new SwingBuilder()
frame = swing.frame(title:'test',
    defaultCloseOperation:WC.DISPOSE_ON_CLOSE) {

    panel(id:'mainPanel'){
        def panelID 

        (1..6).each {
            panelID = 'panel' + it

            panel(alignmentX: 0f, id: panelID , opaque:true ,background : java.awt.Color.GREEN){
                label('description') 
                textField(id: "description$it", text: panelID, columns: 70 )
                button(id: "button$panelID", text: panelID, actionPerformed : {
                    panelID.background = java.awt.Color.RED
                    panelID.repaint()                       
                })
            }
        }
        boxLayout(axis: BXL.Y_AXIS)

        panel(id:'secondPanel' , alignmentX: 0f){                       
            button('Quit', actionPerformed:{
                dispose()
            })
        }
    }       
}
frame.pack()
frame.show()

Answer 1

要根据元素的 ID 获取元素，您需要将 ID 作为 SwingBuilder 的参数进行访问，如下所示：

import groovy.swing.SwingBuilder
import javax.swing.WindowConstants as WC
import javax.swing.JOptionPane
import javax.swing.BoxLayout as BXL

swing = new SwingBuilder()
frame = swing.frame(title:'test', pack:true, visible:true, defaultCloseOperation:WC.DISPOSE_ON_CLOSE) {
    panel(id:'mainPanel'){
        (1..6).each { num ->
            def panelID = "panel$num"
            def pane = panel( alignmentX:0f, id:panelID, background:java.awt.Color.GREEN ) {
                label('description') 
                textField(id: "description$num", text:panelID, columns: 70 )
                button(id: "buttonpanel$num", text:panelID, actionPerformed : {
                    swing."$panelID".background = java.awt.Color.RED
                })
            }
        }
        boxLayout(axis: BXL.Y_AXIS)

        panel(id:'secondPanel' , alignmentX: 0f){                       
            button('Quit', actionPerformed:{
                frame.visible = false
            })
        }
    }       
}