在做基础
java swing程序的时候,我有一个奇怪的错误,我只在我的电脑上(我试过另外两个,一切都很好).
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class ModalDialogsTest extends JFrame implements ActionListener{
private JButton choice;
ModalDialogstest(){
setSize(400,300);
JPanel panel = new JPanel();
getContentPane().add(panel);
panel.setLayout(new BoxLayout(panel,BoxLayout.Y_AXIS));
choice = new JButton("My button");
panel.add(choice);
choice.addActionListener(this);
}
public void actionPerformed(ActionEvent event){
simpleStringChoiceDialog();
}
private void simpleStringChoiceDialog(){
Object[] possibilities = {"choice 1","choice 2","choice 3"};
String s = (String)JOptionPane.showInputDialog(
this,null,JOptionPane.PLAIN_MESSAGE,possibilities,possibilities[0]);
System.out.println(s);
}
public static void main(String[] args) {
ModalDialogsTest newWindow = new ModalDialogstest();
newWindow.setVisible(true);
}
}
问题是当我点击下拉菜单选择一个选项时出现错误.错误是：
java.awt.IllegalComponentStateException: component must be showing on the screen to determine its location
at java.awt.Component.getLocationOnScreen_NoTreeLock(Component.java:2044)
at java.awt.Component.getLocationOnScreen(Component.java:2018)
at sun.lwawt.macosx.CAccessibility$22.call(CAccessibility.java:390)
at sun.lwawt.macosx.CAccessibility$22.call(CAccessibility.java:388)
at sun.lwawt.macosx.LWCToolkit$CallableWrapper.run(LWCToolkit.java:527)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:241)
at sun.lwawt.macosx.LWCToolkit$CPeerEvent.dispatch(LWCToolkit.java:684)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:721)
at java.awt.EventQueue.access$200(EventQueue.java:103)
at java.awt.EventQueue$3.run(EventQueue.java:682)
at java.awt.EventQueue$3.run(EventQueue.java:680)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:691)
at java.awt.EventdispatchThread.pumpOneEventForFilters(EventdispatchThread.java:244)
at java.awt.EventdispatchThread.pumpEventsForFilter(EventdispatchThread.java:163)
at java.awt.EventdispatchThread.pumpEventsForFilter(EventdispatchThread.java:155)
at java.awt.WaitdispatchSupport$2.run(WaitdispatchSupport.java:182)
at java.awt.WaitdispatchSupport$4.run(WaitdispatchSupport.java:221)
at java.security.AccessController.doPrivileged(Native Method)
at java.awt.WaitdispatchSupport.enter(WaitdispatchSupport.java:219)
at java.awt.Dialog.show(Dialog.java:1077)
at javax.swing.JOptionPane.showInputDialog(JOptionPane.java:583)
at ModalDialogsTest.simpleStringChoiceDialog(ModalDialogsTest.java:109)
at ModalDialogsTest.actionPerformed(ModalDialogsTest.java:70)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setpressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6505)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6270)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4861)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.Lightweightdispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.Lightweightdispatcher.processMouseEvent(Container.java:4492)
at java.awt.Lightweightdispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2719)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:723)
at java.awt.EventQueue.access$200(EventQueue.java:103)
at java.awt.EventQueue$3.run(EventQueue.java:682)
at java.awt.EventQueue$3.run(EventQueue.java:680)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:696)
at java.awt.EventQueue$4.run(EventQueue.java:694)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:693)
at java.awt.EventdispatchThread.pumpOneEventForFilters(EventdispatchThread.java:244)
at java.awt.EventdispatchThread.pumpEventsForFilter(EventdispatchThread.java:163)
at java.awt.EventdispatchThread.pumpEventsForHierarchy(EventdispatchThread.java:151)
at java.awt.EventdispatchThread.pumpEvents(EventdispatchThread.java:147)
at java.awt.EventdispatchThread.pumpEvents(EventdispatchThread.java:139)
at java.awt.EventdispatchThread.run(EventdispatchThread.java:97)
choice 2
正如你所看到的,一个错误发生但我仍然可以得到函数的结果所以我没有得到什么错误…任何线索？我在MacOS X Mountain Lion上使用Java 7.
好的,这是你问我的结果：
的System.out.println(System.getProperty( “java.vm.name”));给我：
Java HotSpot(TM) 64-Bit Server VM.
.System.getProperties()名单(的System.out);给我：
-- listing properties -- java.runtime.name=Java(TM) SE Runtime Environment sun.boot.library.path=/Library/Java/JavaVirtualMachines/jdk... java.vm.version=23.3-b01 user.country.format=IE gopherProxySet=false java.vm.vendor=Oracle Corporation java.vendor.url=http://java.oracle.com/ path.separator=: java.vm.name=Java HotSpot(TM) 64-Bit Server VM file.encoding.pkg=sun.io user.country=FR sun.java.launcher=SUN_STANDARD sun.os.patch.level=unkNown java.vm.specification.name=Java Virtual Machine Specification user.dir=/Users/hugo/Documents/workspace/dialogs java.runtime.version=1.7.0_07-b10 java.awt.graphicsenv=sun.awt.CGraphicsEnvironment java.endorsed.dirs=/Library/Java/JavaVirtualMachines/jdk... os.arch=x86_64 java.io.tmpdir=/var/folders/2n/q2bb2df90qqb_x38djlwx... line.separator= java.vm.specification.vendor=Oracle Corporation os.name=Mac OS X sun.jnu.encoding=US-ASCII java.library.path=/Users/hugo/Library/Java/Extensions:/... java.specification.name=Java Platform API Specification java.class.version=51.0 sun.management.compiler=HotSpot 64-Bit Tiered Compilers os.version=10.8 http.nonProxyHosts=local|*.local|169.254/16|*.169.254/16 user.home=/Users/hugo user.timezone= java.awt.printerjob=sun.lwawt.macosx.CPrinterJob file.encoding=US-ASCII java.specification.version=1.7 user.name=hugo java.class.path=/Users/hugo/Documents/workspace/dialo... java.vm.specification.version=1.7 sun.arch.data.model=64 java.home=/Library/Java/JavaVirtualMachines/jdk... sun.java.command=ModalDialogsTest java.specification.vendor=Oracle Corporation user.language=fr user.language.format=en awt.toolkit=sun.lwawt.macosx.LWCToolkit java.vm.info=mixed mode java.version=1.7.0_07 java.ext.dirs=/Users/hugo/Library/Java/Extensions:/... sun.boot.class.path=/Library/Java/JavaVirtualMachines/jdk... java.vendor=Oracle Corporation file.separator=/ java.vendor.url.bug=http://bugreport.sun.com/bugreport/ sun.cpu.endian=little sun.io.unicode.encoding=UnicodeBig sun.font.fontmanager=sun.font.CFontManager socksNonProxyHosts=local|*.local|169.254/16|*.169.254/16 ftp.nonProxyHosts=local|*.local|169.254/16|*.169.254/16 sun.cpu.isalist=
编辑：我忘了提到我尝试在另一个mac上完全像我的(除了我有更多的内存,但没关系)和在Windows 7计算机上.
解决方法
我在Mac Yosemite上遇到了与Java 7相同的问题.在我的情况下,它是由我用于在桌面上安排我的窗口的第三方工具“Cinch”引起的.取消激活该工具会使例外消失.