我正在尝试制作一个简单的Java应用程序,它可以计时,并具有停止和启动计时器的功能。然而,标签不会更新,当我按下开始按钮时,它会冻结。
你能帮我找出问题所在吗?
你能帮我找出问题所在吗?
package random;
import javax.swing.JFrame;
public class Timer {
boolean shouldCount=false;
int int_sec=0;
int int_min=0;
int int_mil=0;
public static void main(String[] args) {
TimeFrame t = new TimeFrame();
JFrame f = new JFrame("Timer");
f.setSize(300,200);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setLocationRelativeTo(null);
f.getContentPane().add(t);
f.setVisible(true);
}
public void count(){
TimeFrame t = new TimeFrame();
if(shouldCount){
long now = System.currentTimeMillis();
while(true){
if(System.currentTimeMillis()-now>=100){
now=System.currentTimeMillis();
String sec = Integer.toString(int_sec);
String min = Integer.toString(int_min);
String mil = Integer.toString(int_mil);
t.update(sec,int_sec,min,mil,int_mil);
int_mil++;
if(int_mil>9){
int_mil=0;
int_sec++;
if(int_sec>=60){
int_sec=1;
int_min++;
}
}
}
}
}
}
}
以下是TimeFrame.java的代码:
package random;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class TimeFrame extends JPanel{
JLabel time = new JLabel("Time goes here", JLabel.CENTER);
Timer t = new Timer();
JButton pause = new JButton ("Pause");
JButton start = new JButton ("Start");
public TimeFrame(){
start.addActionListener(new starts());
pause.addActionListener(new starts());
add(time);
add(start);
add(pause);
}
public void update(String sec,int s, String min,String mil,int m){
if (s<=10){
sec="0"+sec;
}
System.out.println(min+":"+sec+","+mil);
time.setText(min+":"+sec+","+mil);
}
public class starts implements ActionListener{
public void actionPerformed(ActionEvent event){
if(event.getSource() == start){
t.shouldCount=true;
}else{
t.shouldCount=false;
}
t.count();
}
}
}
javax.swing.Timer
而不是while
循环? - BackSlashrunLater()
线程可以让你安全地从其他线程更新GUI线程。 - SnakeDoc