使用java使用计时器交替显示图像 [英] Alternating images with a timer using java

问题描述

由于我不是CS专业，我在将编程愿望转化为实际课程时遇到了一些困难。
它基本上归结为以下内容：如何在标签上交替显示图像，每张图像显示特定于每个图像的时间量。

<那么：说我有图像A和B;我希望用户看到A为1000ms，B为200ms。这会一直循环，直到用户按下某个键。

现在，我可以很容易地将图像加载到面板上，而且我已经管理好了使用KeyListener和东西捕获用户输入，这些都非常好用，并且比我预期的要容易得多。我也知道如何使用循环结构，如while，for和do..while，但这个计时器业务是阴暗的。

我看到各种使用线程的东西，什么不是，我真的不需要它。这不是关于有效的编程或良好的代码，它只是关于展示某些东西。
任何帮助将不胜感激！

解决方案

使用 SwingWorker< Void，Void> 。 SwingWorker的doInBackground方法应该如下所示：

  @Override 
 protected Void doInBackground（）{
尝试{
 while（true）{
 displayImage（imageA）; 
 Thread.sleep（1000L）; 
 if（isCancelled（））{
 return null; 
} 
 displayImage（imageB）; 
 Thread.sleep（200L）; 
 if（isCancelled（））{
 return null; 
} 
} 
} 
 catch（InterruptedException e）{
 // ignore 
} 
返回null; 
} 
 
 private void displayImage（final Icon image）{
 SwingUtilituies.invokeLater（new Runnable（）{
 @Override 
 public void run（） {
 //在面板中显示图像
} 
}）; 
} 
  

keylistener应该只是取消SwingWorker。

Since I'm not a CS major, I'm having some difficulties translating my programming wishes into an actual program. What it basically boils down to is the following: how can I alternate an image on a label, showing each image for an amount of tim specific for each image.

So: say I've images A and B; I'd like the user to see A for 1000ms and B for 200ms. This keeps on looping until a user presses a certain key.

Now, I'm able to load an image onto a panel, quite easily even, and I've managed to catch user input using KeyListener and stuff, which all works quite nicely and alot easier then I had expected. I also know how to use looping constructs like while, for and do..while, but this timer business is shady.

I see all kinds of stuff using threads and what not, I really don't need that. This is not about efficient programming or good code, it's simply about demonstrating something. Any help would be greatly appreciated!

解决方案

Use a SwingWorker<Void, Void>. The doInBackground method of the SwingWorker should look like this :

@Override
protected Void doInBackground() {
    try {
        while (true) {
            displayImage(imageA);
            Thread.sleep(1000L);
            if (isCancelled()) {
                return null;
            }
            displayImage(imageB);
            Thread.sleep(200L);
            if (isCancelled()) {
                return null;
            }
        }
    }
    catch (InterruptedException e) {
        // ignore
    }
    return null;
}

private void displayImage(final Icon image) {
    SwingUtilituies.invokeLater(new Runnable() {
        @Override
        public void run() {
            // display the image in the panel
        }
    });
}

The keylistener should simply cancel the SwingWorker.

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