问题描述
我正在使用JLabel创建动画,
I'm creating an animation using JLabel,
public void updateLabels() {
label.setIcon(new ImageIcon(new Paint().getScaledImage(paint[currentIndexLabel].imageCALA,300,300)));
label_1.setIcon(new ImageIcon(new Paint().getScaledImage(paint[currentIndexLabel].imageStates,300,300)));
label_2.setIcon(new ImageIcon(new Paint().getScaledImage(paint[currentIndexLabel].imageStrategies,300,300)));
label_3.setIcon(new ImageIcon(new Paint().getScaledImage(paint[currentIndexLabel].imagekD,300,300)));
currentIndexLabel++;
}
并且我有一个用于更新标签的按钮
and I have a button that updates the labels
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
while (currentIndexLabel != paint.length-1) {
updateLabels();
}
}
});
但是,我不知道如何等待(例如1000毫秒)直到下一次更改.当我添加此内容时:
But, I don't know how to wait, say for example 1000ms, until next change. When I add this:
try { Thread.sleep(1000); } catch (Exception e){}
进入我的ActionListener:
into my ActionListener:
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
while (currentIndexLabel!=paint.length-1) {
updateLabels();
try { Thread.sleep(1000); } catch (Exception e){}
}
}
});
它不起作用.它只是停了一会儿,我看不到第一帧和最后一帧之间的变化.是否可以在不停止程序的情况下等待1000ms?当我删除while循环并尝试部分时,单击我的按钮,它的变化非常好...
its not working. It just stopping for a while and I don't see changes between the first and last frames. Is it possibile to Wait 1000ms without stopping the program? When I delete the while loop and try section, and click my button it is changing pretty well...
我该怎么做?
推荐答案
在 main 线程中的swing应用程序中使用Thread#sleep
方法将导致GUI冻结(由于该线程处于休眠状态,因此无法进行事件处理)地方).仅允许 SwingWorkers ,并通过他们的#doInBackround
方法.
Using Thread#sleep
method in swing applications in main thread will cause the GUI to freeze (since the thread sleeps, events cannot take place). Thread#sleep
method in swing applications is only allowed to be used only by SwingWorkers, and this in their #doInBackround
method.
为了在swing应用程序中等待(或定期执行某些操作),您将必须使用Swing计时器.看看我做的一个例子:
In order to wait in a swing application (or do something periodically), you will have to use a Swing Timer. Take a look at an example i have made:
import java.awt.FlowLayout;
import java.util.Date;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.Timer; //Note the import
public class TimerExample extends JFrame {
private static final int TIMER_DELAY = 1000;
private Timer timer;
public TimerExample () {
super();
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(200, 200);
setLocationRelativeTo(null);
getContentPane().setLayout(new FlowLayout());
timer = new Timer(TIMER_DELAY, e -> {
System.out.println("Current Time is: " + new Date(System.currentTimeMillis()));
});
//timer.setRepeats(false); //Do it once, or repeat it?
JButton button = new JButton("Start");
button.addActionListener(e -> timer.start());
getContentPane().add(button);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> new TimerExample().setVisible(true));
}
}
在开始"之后的输出.按下按钮:
Output after "Start" button is pressed:
当前时间是:EET 2019星期一2月25日13:30:45
Current Time is: Mon Feb 25 13:30:45 EET 2019
当前时间是:EET 2019星期一2月25日13:30:46
Current Time is: Mon Feb 25 13:30:46 EET 2019
如您所见,Timer的动作侦听器每秒触发一次.
As you can see, Timer's action listener fires every second.
所以在您的情况下:
timer = new Timer(TIMER_DELAY, e -> {
if (currentIndexLabel != paint.length-1) {
upateLabels();
timer.restart(); //Do this check again after 1000ms
}
});
button.addActionListener(e -> timer.start());
这篇关于如何在Java Swing应用程序中暂停/睡眠/等待?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!