Question

我正在尝试在RCP应用程序中创建一个最初不可见的标签。当我单击“保存”按钮时，它变为可见。同样，它应该在5秒内不可见。

为此，我写了以下代码：

saveButton.addSelectionListener(new SelectionListener() {

            @Override
            public void widgetSelected(SelectionEvent e) {
                // TODO Auto-generated method stub
                System.out.println(textName.getText());
                String text = textName.getText();
                tree.getSelection()[0].setText(text);
                String nodeId = ((TreeStructure) tree.getSelection()[0]
                        .getData()).getNodeId();
                // update the database
                UpdateTree updateTree = new UpdateTree();
                updateTree.renameNode(text, nodeId);
                label.setBounds(xForFirstButton, yIndexForButtons
                        + Constants.BUTTON_BUFFER, Constants.BUTTON_WIDTH,
                        Constants.BUTTON_HEIGHT);
                label.setVisible(true);

                AbstractAction myAction = new AbstractAction() {

                    private static final long serialVersionUID = 1L;

                    @Override
                    public void actionPerformed(ActionEvent arg0) {
                        // TODO Auto-generated method stub
                        label.setVisible(false);
                    }
                };

                Timer myTimer = new Timer(5000, myAction);
                myTimer.start();
            }

但是，这段代码在运行时会出现以下错误：

Exception in thread "AWT-EventQueue-0" org.eclipse.swt.SWTException: Invalid thread access
    at org.eclipse.swt.SWT.error(SWT.java:4441)
    at org.eclipse.swt.SWT.error(SWT.java:4356)
    at org.eclipse.swt.SWT.error(SWT.java:4327)
    at org.eclipse.swt.widgets.Widget.error(Widget.java:476)
    at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:367)
    at org.eclipse.swt.widgets.Control.setVisible(Control.java:3781)
    at com.app.editor.views.EditorView$2$1.actionPerformed(EditorView.java:183)
    at javax.swing.Timer.fireActionPerformed(Unknown Source)
    at javax.swing.Timer$DoPostEvent.run(Unknown Source)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(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)

可以请任何人指出问题是什么？

提前致谢！

Answer 1

更改UI的所有代码必须在UI线程中运行 - Timer正在不同的线程中运行代码。

而不是Timer使用：

Display.getDefault().timerExec(milliseconds, runnable);

Answer 2

要从一个不是ui线程的线程更新ui，你必须使用它：

Display.getDefault().syncExec(new Runnable() {
     public void run() {
           // Update UI here
     }
});

syncExec将在您的rcp应用程序的ui线程中执行您的操作。

这类似于Swing中的invokeLater()方法。

如何在Eclipse RCP应用程序中5秒后自动隐藏标签？

2 个答案: