java - 使用 Eclipse 在 Java 中使用定时器

Question

我正在尝试使用 Eclipse 在 Java 中编写一个小程序，但我有点不知所措。

谁能给我解释一下(以“傻瓜式”的方式)我需要做什么才能使用计时器重绘表单？

我正在尝试做一些像时钟一样简单的事情。我需要一个计时器来每秒重绘它。

像这样:

private void activateTimer()
{
    ActionListener myAction;
    myAction = new ActionListener () 
    { 
        public void actionPerformed(ActionEvent e) 
        { 
           whatever.redraw();
         } 

    };
    myTimer = new Timer(1000, myAction);
    myTimer.start();
}

当必须执行操作时，我收到错误:

*Exception in thread "AWT-EventQueue-0" org.eclipse.swt.SWTException: Invalid thread access*

这是我收到的完整异常:

Exception in thread "AWT-EventQueue-0" org.eclipse.swt.SWTException: Invalid thread access
    at org.eclipse.swt.SWT.error(SWT.java:4282)
    at org.eclipse.swt.SWT.error(SWT.java:4197)
    at org.eclipse.swt.SWT.error(SWT.java:4168)
    at org.eclipse.swt.widgets.Widget.error(Widget.java:468)
    at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:359)
    at org.eclipse.swt.widgets.Control.redraw(Control.java:2327)
    at default.myTimer$1.actionPerformed(myTimer.java:97)
    at javax.swing.Timer.fireActionPerformed(Unknown Source)
    at javax.swing.Timer$DoPostEvent.run(Unknown Source)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$000(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

关于每秒刷新屏幕的任何想法或示例？

我已按照其中一个答案中的说明进行操作，但仍然收到相同的错误。

Answer 1

您必须将其拆分为单独的方法，最好使用 javax.swing.Action 而不是 ActionListener

private void activateTimer(){
    myTimer = new Timer(1000, myAction);
    myTimer.start();
}

private Action myAction = new AbstractAction() {

    private static final long serialVersionUID = 1L;

    @Override
    public void actionPerformed(ActionEvent e) {
          whatever.redraw();
    }
};