Eclipse JFace的向导

Question

我需要一个向导,第二页内容取决于第一页的选择.第一页询问用户他想要创建的过滤器的"种类",第二页要求用户创建所选"种类"的一个过滤器实例.

JFace的向导页面内容(createControl(...)方法)都是在向导打开时创建的,而不是在显示给定页面时创建的(这允许JFace知道向导大小,我猜??).

因此,我必须在向导打开之前创建我的第二页内容但是我不能,因为第二页的内容取决于第一页的选择.

现在我找到的更清洁的解决方案包括在向导打开之前创建所有(秒)页面(带有它们的内容)并覆盖第一页实现中的getNextPage()方法.

该解决方案的主要缺点是,当要创建许多第二页时,它可能很昂贵.

您对该解决方案有何看法？你如何管理向导的页面？有没有我错过的清洁解决方案？

Answer 1

如果你是其他几个页面,那么这种方法是正确的

• 与另一个完全不同
• 取决于之前页面中的先前选择

然后你可以动态添加下一页(也如这里所述)

但是,如果您只有一个包含动态内容的下一页,您应该能够在该方法中创建该内容onEnterPage()

public void createControl(Composite parent)
{
    //
    // create the composite to hold the widgets
    //
    this.composite = new Composite(parent, SWT.NONE);

    //
    // create the desired layout for this wizard page
    //
    GridLayout layout = new GridLayout();
    layout.numColumns = 4;
    this.composite.setLayout(layout);

    // set the composite as the control for this page
    setControl(this.composite);
}

void onEnterPage()
{
    final MacroModel model = ((MacroWizard) getWizard()).model;
    String selectedKey = model.selectedKey;
    String[] attrs = (String[]) model.macroMap.get(selectedKey);

    for (int i = 0; i < attrs.length; i++)
    {
        String attr = attrs[i];
        Label label = new Label(this.composite, SWT.NONE);
        label.setText(attr + ":");

        new Text(this.composite, SWT.NONE);
    }
    pack();
}

如eclipse角文章创建JFace向导所示:

我们可以通过覆盖任何向导页面的getNextPage方法来更改向导页面的顺序.在离开页面之前,我们在模型中保存用户选择的值.在我们的示例中,根据旅行的选择,用户接下来会看到带有航班的页面或开车旅行的页面.

public IWizardPage getNextPage(){
   saveDataToModel();       
   if (planeButton.getSelection()) {
       PlanePage page = ((HolidayWizard)getWizard()).planePage;
     page.onEnterPage();
       return page;
   }
   // Returns the next page depending on the selected button
   if (carButton.getSelection()) { 
    return ((HolidayWizard)getWizard()).carPage;
   }
   return null;
}

我们定义这样做初始化的方法PlanePage,onEnterPage()并移动到当我们调用此方法PlanePage,那就是在getNextPage()第一页的方法.

Answer 2

如果要根据第一页上的选择启动新向导,可以使用JFace基类org.eclipse.jface.wizard.WizardSelectionPage.

下面的示例显示了扩展点定义的可用向导列表.按" 下一步"时,将启动所选向导.

public class ModelSetupWizardSelectionPage extends WizardSelectionPage {

private ComboViewer providerViewer;
private IConfigurationElement selectedProvider;

public ModelSetupWizardSelectionPage(String pageName) {
    super(pageName);
}

private class WizardNode implements IWizardNode {
    private IWizard wizard = null;
    private IConfigurationElement configurationElement;

    public WizardNode(IConfigurationElement c) {
        this.configurationElement = c;
    }

    @Override
    public void dispose() {

    }

    @Override
    public Point getExtent() {
        return new Point(-1, -1);
    }

    @Override
    public IWizard getWizard() {
        if (wizard == null) {
            try {
                wizard = (IWizard) configurationElement
                        .createExecutableExtension("wizardClass");
            } catch (CoreException e) {

            }
        }
        return wizard;
    }

    @Override
    public boolean isContentCreated() {
        // TODO Auto-generated method stub
        return wizard != null;
    }

}

@Override
public void createControl(Composite parent) {
    setTitle("Select model provider");
    Composite main = new Composite(parent, SWT.NONE);
    GridLayout gd = new GridLayout(2, false);
    main.setLayout(gd);
    new Label(main, SWT.NONE).setText("Model provider");
    Combo providerList = new Combo(main, SWT.NONE);
    providerViewer = new ComboViewer(providerList);
    providerViewer.setLabelProvider(new LabelProvider() {
        @Override
        public String getText(Object element) {
            if (element instanceof IConfigurationElement) {
                IConfigurationElement c = (IConfigurationElement) element;
                String result = c.getAttribute("name");
                if (result == null || result.length() == 0) {
                    result = c.getAttribute("class");
                }
                return result;
            }
            return super.getText(element);
        }

    });
    providerViewer
            .addSelectionChangedListener(new ISelectionChangedListener() {
                @Override
                public void selectionChanged(SelectionChangedEvent event) {
                    ISelection selection = event.getSelection();
                    if (!selection.isEmpty()
                            && selection instanceof IStructuredSelection) {
                        Object o = ((IStructuredSelection) selection)
                                .getFirstElement();
                        if (o instanceof IConfigurationElement) {
                            selectedProvider = (IConfigurationElement) o;
                            setMessage(selectedProvider.getAttribute("description"));
                            setSelectedNode(new WizardNode(selectedProvider));
                        }
                    }

                }
            });
    providerViewer.setContentProvider(new ArrayContentProvider());
    List<IConfigurationElement> providers = new ArrayList<IConfigurationElement>();
    IExtensionRegistry registry = Platform.getExtensionRegistry();
    IExtensionPoint extensionPoint = registry
            .getExtensionPoint(<your extension point namespace>,<extension point name>);
    if (extensionPoint != null) {
        IExtension extensions[] = extensionPoint.getExtensions();
        for (IExtension extension : extensions) {
            IConfigurationElement configurationElements[] = extension
                    .getConfigurationElements();
            for (IConfigurationElement c : configurationElements) {
                providers.add(c);
            }
        }
    }
    providerViewer.setInput(providers);
    setControl(main);

}

相应的向导类如下所示:

 public class ModelSetupWizard extends Wizard {

private ModelSetupWizardSelectionPage wizardSelectionPage;

public ModelSetupWizard() {
    setForcePreviousAndNextButtons(true);
}

@Override
public boolean performFinish() {
            // Do what you have to do to finish the wizard
    return true;
}

@Override
public void addPages() {
    wizardSelectionPage = new ModelSetupWizardSelectionPage("Select a wizard");
    addPage(wizardSelectionPage);

}
}