當我使用java.awt.Canvas時，JSplitPane不會調整大小？

Question

我有一個簡單的例子，我使用java.awt.Canvas作爲JSplitPane中的組件，JSplitPane不允許調整。誰能解釋爲什麼？ （更重要的是，如何解決）

VerticalSplit.java：

import java.awt.BorderLayout; 
import java.awt.Component; 
import javax.swing.JPanel; 
import javax.swing.JSplitPane; 

abstract public class VerticalSplit { 
    public VerticalSplit(JPanel panel) 
    { 
     panel.setLayout(new BorderLayout()); 
     JSplitPane jsp = new JSplitPane(JSplitPane.VERTICAL_SPLIT, 
      createComponent1(), createComponent2()); 
     jsp.setResizeWeight(0.5); 
     panel.add(jsp, BorderLayout.CENTER); 
    } 
    abstract protected Component createComponent1(); 
    abstract protected Component createComponent2(); 
} 

CanvasTest1.java：（如！@tulskiy建議 - 感謝）

import java.awt.Canvas; 
import java.awt.Component; 
import java.awt.Dimension; 
import java.awt.Graphics; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 

public class CanvasTest1 extends VerticalSplit 
{ 
    static public class PlainCanvas extends Canvas 
    { 
     @Override public void paint(Graphics g) 
     { 
      Dimension d = getSize(); 
      int h = getHeight(); 
      int w = getWidth(); 
      g.drawRect(0,0,w,h); 
      g.drawLine(0,0,w,h); 
      g.drawLine(0,h,w,0); 
     } 
    }; 

    public CanvasTest1(JPanel panel) { super(panel); } 

    @Override protected Component createComponent1() { 
     return new PlainCanvas(); 
    } 

    @Override protected Component createComponent2() { 
     return new PlainCanvas(); 
    } 

    public static void main(String[] args) { 
     JPanel panel = new JPanel(); 
     CanvasTest1 test = new CanvasTest1(panel); 

     JFrame frame = new JFrame(test.getClass().getName()); 
     frame.setContentPane(panel); 

     frame.pack(); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.setVisible(true); 
    } 
} 

Answer 1

從畫布更改爲的JPanel使其正常工作。