swing各組件重繪外觀

JPanle、JButton、JLabel等等組件，若想實現漂亮的外觀，可以通過實現paintComponent(Graphics g)來完成。

樣本：自訂JButton的滑鼠經過與滑鼠離開的效果。

一、建立NewButton類

package background;import java.awt.Graphics;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import javax.swing.ImageIcon;import javax.swing.JButton;public class NewButton extends JButton {ImageIcon icon = null;public NewButton(){setBorder(null);//取消邊框icon = new ImageIcon("button1.png");this.addMouseListener(new MouseAdapter() {@Overridepublic void mouseExited(MouseEvent e) {//滑鼠離開icon = new ImageIcon("button1.png");repaint();//重繪圖形,調用paintComponent}@Overridepublic void mouseEntered(MouseEvent e) {//滑鼠經過icon = new ImageIcon("button2.png");repaint();}});}public void paintComponent(Graphics g){int x=0,y=0;g.drawImage(icon.getImage(), x, y, 95, 32, this);}}

二、主視窗JFrameDemo

package background;import javax.swing.ImageIcon;import javax.swing.JFrame;public class JFrameDemo extends JFrame {public JFrameDemo(){super("Jpanel Background Demo");//視窗標題NewButton b2 = new NewButton();this.getContentPane().add(b2);//將button加入視窗this.setSize(95, 32);this.setLocationRelativeTo(null);//設定視窗置中this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);this.setVisible(true);}/** * @param args */public static void main(String[] args) {new JPanelDemo();}}

通過實現paintComponent可以實現各個組件的自訂外觀。