我的问题很简单,代码很复杂,答案也不容易找到,所以我正在寻求帮助。
我正在编写多线程应用程序,以下是它的工作原理:
1)一个线程正在读取文件并从文本文件中解析信息(每500毫秒尝试到达文件的末尾)
2)当找到相关信息时,线程将其存储并通知作为观察者的控制器
3)当通知控制器时,它通知另一个线程(GUI)更新我想向用户显示的信息。
除非我调用revalide()
或validate()
或repaint()
,否则会出现异常,因为GUI经常更新。
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: No such child: 7
at java.awt.Container.getComponent(Container.java:323)
at javax.swing.JComponent.rectangleIsObscured(JComponent.java:4393)
at javax.swing.JComponent.paint(JComponent.java:1052)
at javax.swing.JComponent.paintToOffscreen(JComponent.java:5206)
at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1493)
at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1424)
at javax.swing.RepaintManager.paint(RepaintManager.java:1217)
at javax.swing.JComponent._paintImmediately(JComponent.java:5154)
at javax.swing.JComponent.paintImmediately(JComponent.java:4964)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:781)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:739)
at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:688)
at javax.swing.RepaintManager.access$700(RepaintManager.java:59)
at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1632)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:660)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
我考虑过运行另一个线程,每500毫秒可能尝试revalidate()
GUI,但可能有更好的选择。
有什么我应该担心的,比如在我调用revalidate()
之前停止GUI线程然后恢复它或类似的东西?
是的,我确实从面板中删除了组件(JLabel),用具有新数据的组件替换它们。我会试试你说的话。
顺便说一下,invokelater和另一个线程之间有很大的区别吗?
解决方案:
我创建了一个如下所示的方法:
protected void updateGUI(final Param param1, final Param param2){
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
//write your code
param1.validate();
param1.repaint();
}
});
答案 0 :(得分:2)
在我看来,EDT之外的GUI发生了一些例外情况,这会让所有人感到困惑:更具体地说,当GUI想要重新绘制它时,组件似乎被移除了。
尝试将添加/删除组件的代码作为Runnable
传递给SwingUtilities.invokeLater()
,以确保以任何方式更改GUI的所有内容都已同步。