scala swing：可拖动/可调整大小的组件特性

Question

我正在寻找一个scala特性，我可以混合到一个scala.swing.Component，这将允许使用鼠标输入定位和调整大小。

理想情况下，会增加小盒子为“手柄”，以指示该组件可以调整用户：

我觉得这是一个相当普遍的任务，应该有一些特质在那里支持它。

Answer 1

我在我目前的项目中使用这些。您可能需要用自己的库替换Vector库并添加隐含的defs。或者使用来自挥杆的点/维度。该组件需要在一个面板，允许自定义的位置和大小，像NullPanel从http://dgronau.wordpress.com/2010/08/28/eine-frage-des-layouts/

trait Movable extends Component{ 
    var dragstart:Vec2i = null 
    listenTo(mouse.clicks, mouse.moves) 
    reactions += { 
     case e:MouseDragged => 
      if(dragstart != null) 
       peer.setLocation(location - dragstart + e.point) 
     case e:MousePressed => 
      this match { 
       case component:Resizable => 
        if(component.resizestart == null) 
         dragstart = e.point 
       case _ => 
        dragstart = e.point 

      } 
     case e:MouseReleased => 
      dragstart = null  
    } 
} 

trait Resizable extends Component{ 
    var resizestart:Vec2i = null 
    var oldsize = Vec2i(0) 
    def resized(delta:Vec2i) {} 
    listenTo(mouse.clicks, mouse.moves) 
    reactions += { 
     case e:MouseDragged => 
      if(resizestart != null){ 
       val delta = e.point - resizestart 
       peer.setSize(max(oldsize + delta, minimumSize)) 

       oldsize += delta 
       resizestart += delta 

       resized(delta) 
       revalidate 
      } 
     case e:MousePressed => 
      if(size.width - e.point.x < 15 
      && size.height - e.point.y < 15){ 
       resizestart = e.point 
       oldsize = size 

       this match { 
        case component:Movable => 
         component.dragstart = null 
        case _ => 
       } 
      } 
     case e:MouseReleased => 
      resizestart = null 
    } 
} 

Answer 2

我知道的唯一一个组件是Dragable，可调整大小是JDesktop上的InternalFrame。这里是一个例子：

import swing._ 
import event._ 

import javax.swing.{UIManager,JComponent} 
import javax.swing.KeyStroke.getKeyStroke 
import java.awt.{Graphics2D,Graphics} 

object InternalFrameDemo extends SimpleSwingApplication{ 
    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName) 

    val top = new MainFrame{ 
     title = "InternalFrameDemo" 
     preferredSize = new Dimension(640,480) 
     val desktop = new javax.swing.JDesktopPane 

     val jc = new JComponent{ 
      override def paint(g:Graphics){ 
       import g._ 
       drawLine(0,0,20,20) 
       drawLine(0,20,20,0) 
       println("yay draw") 
      } 

      setVisible(true) 
     } 

     desktop add jc 

     contents = Component.wrap(desktop) 

     menuBar = new MenuBar{ 
      contents += new Menu("Document"){ 
       mnemonic = Key.D 

       contents += new MenuItem("New"){ 
        mnemonic = Key.N 
        action = new Action("new"){ 
         def apply = createFrame 
         accelerator = Some(getKeyStroke("alt N")) 
        } 
       } 

       contents += new MenuItem("Quit"){ 
        mnemonic = Key.Q 
        action = new Action("quit"){ 
         def apply(){ 
          quit() 
         } 
         accelerator = Some(getKeyStroke("alt Q")) 
        } 
       } 
      } 
     } 

     def createFrame{ 
      val newFrame = MyInternalFrame() 
      newFrame setVisible true 
      desktop add newFrame 
      newFrame setSelected true 

     } 
    } 
} 

import javax.swing.{JDesktopPane,JInternalFrame} 
import collection.mutable.ArrayBuffer 

object MyInternalFrame{ 
    var openFrameCount = 0; 
    val xOffset, yOffset = 30; 

    def apply() = { 
     openFrameCount += 1 
     val jframe = new javax.swing.JInternalFrame("Document #" + openFrameCount,true,true,true,true) 

     jframe.setSize(300,300) 
     jframe.setLocation(xOffset*openFrameCount,yOffset*openFrameCount) 

     jframe //Component.wrap(jframe) 
    } 
} 

但是JInternalFrame和JDesktop没有集成在scala swing包中，需要手动打包。