我编写了程序来绘制轮子(有 6 段的圆圈)和不同颜色的每个段。并为轮子设置动画..
这是代码:
public class ExamWheel extends JFrame implements ActionListener{
JButton b_start = new JButton("Start");
JButton b_stop = new JButton("Stop");
Thread th;
Boolean doDraw = true;
public ExamWheel(){
setSize(400,400);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setTitle("Wheel..");
//add(b_start);
this.setLayout (new FlowLayout());
this.add(b_stop);
b_start.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
if(e.getSource()==b_start)
doDraw=true;
}
public void paint(Graphics graphics) {
if (doDraw){
super.paint(graphics);
Graphics2D g = (Graphics2D) graphics;
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
try{
// draw the circle
for(int i=0; ; i=i+1){
g.setColor(Color.CYAN);
g.fillArc(50, 50, 300, 300, i+0, 60);
th.sleep(1);
g.setColor(Color.red);
g.fillArc(50, 50, 300, 300, i+60, 60);
th.sleep(1);
g.setColor(Color.green);
g.fillArc(50, 50, 300, 300, i+120, 60);
th.sleep(1);
g.setColor(Color.blue);
g.fillArc(50, 50, 300, 300, i+180, 60);
th.sleep(1);
g.setColor(Color.gray);
g.fillArc(50, 50, 300, 300, i+240, 60);
th.sleep(1);
g.setColor(Color.pink);
g.fillArc(50, 50, 300, 300, i+300, 60);
th.sleep(1);
}
}
catch(InterruptedException e){
Thread.currentThread().interrupt();
}
}
}
public static void main(String[] args) {
ExamWheel f = new ExamWheel();
}
}
问题:它是无限循环,我无法停止它或关闭框架。
所以我有想法:
我创建了值为true的布尔变量(doDraw),并添加了JButton,当单击按钮时,变量将变为false,在paint()方法中,我将首先使用paint()的if条件
问题:我无法使用paint() 将JButton 添加到Frame,我该怎么办?
注意:我尝试使用paintComponent(),但循环(for with thread)不起作用。
解决了感谢 Pete Kirham
我添加了 Timer 并用paintComponent() 替换了paint()
public class ExamWheel extends JPanel implements ActionListener {
int i=0;
Timer tm = new Timer(10, this);
public void paintComponent(Graphics graphics) {
super.paintComponent(graphics);
Graphics2D g = (Graphics2D) graphics;
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.setColor(Color.CYAN);
g.fillArc(50, 50, 300, 300, i+0, 60);
g.setColor(Color.red);
g.fillArc(50, 50, 300, 300, i+60, 60);
g.setColor(Color.green);
g.fillArc(50, 50, 300, 300, i+120, 60);
g.setColor(Color.blue);
g.fillArc(50, 50, 300, 300, i+180, 60);
g.setColor(Color.gray);
g.fillArc(50, 50, 300, 300, i+240, 60);
g.setColor(Color.pink);
g.fillArc(50, 50, 300, 300, i+300, 60);
tm.start();
}
public void actionPerformed(ActionEvent e) {
i++;
repaint();
}
public static void main(String[] args) {
ExamWheel wh = new ExamWheel();
JFrame jf = new JFrame();
jf.setSize(500,500);
jf.setResizable(false);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setLocationRelativeTo(null);
jf.setTitle("Wheel..");
jf.add(wh);
}