Question

我遇到了使用org.eclipse.ui.forms.widgets.Section时遇到的问题，如果我向其添加子项并通过启用子项或在其上设置文本来修改子项，则会出现异常。我写了一个小片段，可以轻松地重现下面的问题：

import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.forms.widgets.Section;

public class SectionTest {
    /**
     * @param args
     */
    public static void main(String[] args) {
        final Display display = new Display ();
        final Shell shell = new Shell (display);
        shell.setLayout(new GridLayout());

        Button b = new Button(shell, SWT.PUSH);
        b.addSelectionListener(new SelectionAdapter() {
            @Override
            public void widgetSelected(SelectionEvent e) {
                addSection(shell);
            }
        });
        b.setText("Add");

        addSection(shell);

        shell.setSize(300, 300);
        shell.open();
        while (!shell.isDisposed()) {
            try {
                if (!display.readAndDispatch())
                    display.sleep();
            }
            catch (Exception e) {
                e.printStackTrace();
                MessageDialog.openError(shell, "Error", e.getMessage());
            }
        }
        display.dispose();
    }

    private static void addSection(Composite parent) {
        Section section = new Section(parent, Section.TITLE_BAR | Section.TREE_NODE | Section.CLIENT_INDENT);
        section.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));
        section.setText("Hello");
        //section.setSize(1, 1);

        // Add the check button for enabling/disabling this group
        Button enableControl = new Button(section, SWT.CHECK);
        enableControl.setText("Enable");
        section.setTextClient(enableControl);

        Composite client = new Composite(section, SWT.NONE);
        section.setClient(client);
        client.setLayout(new GridLayout());

        Button b = new Button(client, SWT.PUSH);
        b.setText("one");

        b = new Button(client, SWT.PUSH);
        b.setText("two");
        parent.layout();
    }
}

如果您运行代码，则会出现一个带有添加按钮的对话框。单击添加按钮将产生异常。

例外文字：

java.lang.IllegalArgumentException: Argument not valid
    at org.eclipse.swt.SWT.error(SWT.java:4342)
    at org.eclipse.swt.SWT.error(SWT.java:4276)
    at org.eclipse.swt.SWT.error(SWT.java:4247)
    at org.eclipse.swt.graphics.Image.init(Image.java:1558)
    at org.eclipse.swt.graphics.Image.<init>(Image.java:181)
    at org.eclipse.ui.forms.widgets.Section.onPaint(Section.java:344)
    at org.eclipse.ui.forms.widgets.ExpandableComposite$1.paintControl(ExpandableComposite.java:560)
    at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:230)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1077)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1062)
    at org.eclipse.swt.widgets.Composite.WM_PRINTCLIENT(Composite.java:1639)
    at org.eclipse.swt.widgets.Control.windowProc(Control.java:4590)
    at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:341)
    at org.eclipse.swt.widgets.Display.windowProc(Display.java:4976)
    at org.eclipse.swt.internal.win32.OS.CallWindowProcW(Native Method)
    at org.eclipse.swt.internal.win32.OS.CallWindowProc(OS.java:2440)
    at org.eclipse.swt.widgets.Button.callWindowProc(Button.java:343)
    at org.eclipse.swt.widgets.Control.windowProc(Control.java:4623)
    at org.eclipse.swt.widgets.Display.windowProc(Display.java:4976)
    at org.eclipse.swt.internal.win32.OS.SetWindowTextW(Native Method)
    at org.eclipse.swt.internal.win32.OS.SetWindowText(OS.java:3461)
    at org.eclipse.swt.widgets.Button._setText(Button.java:300)
    at org.eclipse.swt.widgets.Button.setText(Button.java:1099)
    at org.eclipse.swt.snippets.SectionTest.addSection(SectionTest.java:58)
    at org.eclipse.swt.snippets.SectionTest.access$0(SectionTest.java:50)
    at org.eclipse.swt.snippets.SectionTest$1.widgetSelected(SectionTest.java:28)
    at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:248)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
    at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4169)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3758)
    at org.eclipse.swt.snippets.SectionTest.main(SectionTest.java:39)

在Windows 7 64位计算机上使用32位JRE（和eclipse）会出现此问题。同样的问题在Windows XP（32位）上无法重现。

我的问题是，我做错了导致此异常。如果您注意到我在shell打开之前使用相同的方法添加了一个部分并且它运行没有任何问题，但是一旦shell打开并且可见，调用相同的addSection(Composite)方法会导致异常。

注意：取消注释'section.setSize（1,1）;'行在addSection(Composite)中将“隐藏”问题，但这似乎不是正确的事情。使用Sections的正确方法是什么？

编辑：在ecilpse https://bugs.eclipse.org/bugs/show_bug.cgi?id=309443中发现了一个已经报告过的问题，这个问题似乎与此问题相同。

在org.eclipse.ui.forms.widgets.Section中修改子项会导致异常

0 个答案: