代碼如下

import java.awt.*;import javax.swing.*;//圖形計數器JCounter三位class JCounter extends JPanel {        PRivate static final long serialVersionUID = 1L;        private ImageIcon [] numSet = { new ImageIcon("image/c0.gif"), new ImageIcon("image/c1.gif"),                                             new ImageIcon("image/c2.gif"), new ImageIcon("image/c3.gif"),                                             new ImageIcon("image/c4.gif"), new ImageIcon("image/c5.gif"),                                             new ImageIcon("image/c6.gif"), new ImageIcon("image/c7.gif"),                                             new ImageIcon("image/c8.gif"), new ImageIcon("image/c9.gif"),                                        };        private JButton [] counter = { new JButton(numSet[0]), new JButton(numSet[0]), new JButton(numSet[0])};        private int counterNum;        private Insets space;        public JCounter() {                this(0);        }        public JCounter(int num) {                super();                setSize(23, 39);                                space = new Insets(0,0,0,0);                this.counterNum = num;                for (int i=0; i< 3; i++){                        counter[i].setSize(13,23);                        counter[i].setMargin(space);                        add(counter[i]);                }                                this.setVisible(true);                 resetImage();                 }                public int getCounterNum() {                        return(counterNum);        }                private void setCounterNum(int num){                this.counterNum = num;        }                private void resetImage() {                int ones, tens, hundreds;                ones = counterNum % 10 ;                tens = counterNum % 100/10;                hundreds = (counterNum) % 1000/100;                this.counter[0].setIcon(numSet[hundreds]);                this.counter[1].setIcon(numSet[tens]);                this.counter[2].setIcon(numSet[ones]);        }                public void resetCounter(int num) {                setCounterNum(num);                resetImage();                this.repaint();        }        public static void main(String[] args) {                JFrame jf = new JFrame("Test");                jf.setSize(23,39);                JCounter jc = new JCounter();                jf.setContentPane(jc);                jf.show();                                jc.resetCounter(394);        }                }

效果圖<ignore_js_op>

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