Eclipse New Wizard的Wizard

Eclipse点击New-->Other以后出来一个新建的向导页面. 是一颗树, 选择某个节点以后就可以Next下去了.

其实后面的页面也是Wizard. 也就是说本身也可以独立成为一个WizardDialog, 那么如何将其嵌入到这个总开头页面之后呢?

Eclipse的实现方法看了很久都没有看懂, 最后决定自己尝试其他思路.

看代码:

IWizard wizard = new NewObjectWizard();
WizardDialog dialog = new WizardDialog(window.getShell(), wizard);
dialog.create();
dialog.open();

这是呼出第一个页面的Action的代码, 出来的页面就是一棵树的样子, 当然那棵树是在NewObjectWizard里面实现的.

public class NewObjectWizard extends Wizard implements IWizard ...{
    private IWizard currentWizard = null;

    private Composite pageContainer;

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#addPages()
     */
    @Override
    public void addPages() ...{
        super.addPage(new NewObjectWizardPage());
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#performFinish()
     */
    @Override
    public boolean performFinish() ...{
        return false;
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#getWindowTitle()
     */
    @Override
    public String getWindowTitle() ...{
        return StingIDEMessages.NewWizardDialog_title;
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#needsPreviousAndNextButtons()
     */
    @Override
    public boolean needsPreviousAndNextButtons() ...{
        return true;
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#needsProgressMonitor()
     */
    @Override
    public boolean needsProgressMonitor() ...{
        return false;
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#getNextPage(org.eclipse.jface.wizard.IWizardPage)
     */
    @Override
    public IWizardPage getNextPage(IWizardPage page) ...{
        if (page.getName().equals(
                NewObjectWizardPage.NEW_OBJECT_WIZARD_PAGE_NAME)) ...{
            if (currentWizard == null) ...{
                return null;
            } else ...{
                return currentWizard.getStartingPage();
            }
        } else ...{
            return page.getNextPage();
        }
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#getPreviousPage(org.eclipse.jface.wizard.IWizardPage)
     */
    @Override
    public IWizardPage getPreviousPage(IWizardPage page) ...{
        if (page.getName().equals(
                NewObjectWizardPage.NEW_OBJECT_WIZARD_PAGE_NAME))
            return null;

        IWizardPage previous = page.getPreviousPage();
        if (previous == null) ...{
            return getPage(NewObjectWizardPage.NEW_OBJECT_WIZARD_PAGE_NAME);
        } else ...{
            return previous;
        }
    }

    /**//**
     * 设置当前得向导
     */
    void setCurrentWizard(IWizard wizard) ...{
        this.currentWizard = wizard;
        if (wizard != null) ...{
            wizard.addPages();
            wizard.createPageControls(pageContainer);
        }
        getContainer().updateButtons();
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#createPageControls(org.eclipse.swt.widgets.Composite)
     */
    @Override
    public void createPageControls(Composite pageContainer) ...{
        super.createPageControls(pageContainer);
        this.pageContainer = pageContainer;
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#canFinish()
     */
    @Override
    public boolean canFinish() ...{
        return currentWizard != null && currentWizard.canFinish();
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#dispose()
     */
    @Override
    public void dispose() ...{
        this.currentWizard = null;
        this.pageContainer = null;
        super.dispose();
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#getPage(java.lang.String)
     */
    @Override
    public IWizardPage getPage(String name) ...{
        if (name.equals(NewObjectWizardPage.NEW_OBJECT_WIZARD_PAGE_NAME)) ...{
            return super.getPage(name);
        } else if (this.currentWizard != null) ...{
            return currentWizard.getPage(name);
        } else
            return null;
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#getPageCount()
     */
    @Override
    public int getPageCount() ...{
        if (currentWizard != null) ...{
            return currentWizard.getPageCount() + super.getPageCount();
        }
        return super.getPageCount();
    }

    /**//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.wizard.Wizard#getPages()
     */
    @Override
    public IWizardPage[] getPages() ...{
        if (getPageCount() == 1)
            return super.getPages();
        else ...{
            IWizardPage[] pages = new IWizardPage[getPageCount()];
            IWizardPage[] myPages = super.getPages();
            System.arraycopy(myPages, 0, pages, 0, myPages.length);
            IWizardPage[] dynamicPages = currentWizard.getPages();
            System.arraycopy(dynamicPages, 0, pages, 1, dynamicPages.length);
            return pages;
        }
    }
}

可以看到很多方法都被重写掉了, 主要就是控制当前这个Wizard到底有多少个Page, 当然物理上是只有一个的, 通过重写方法来将其和树上选择的Wizard结合起来看.

public class NewObjectWizardPage extends WizardPage ...{
    static final String NEW_OBJECT_WIZARD_PAGE_NAME = "#NewObjectWizardPage";

    protected NewObjectWizardPage() ...{
        super(NEW_OBJECT_WIZARD_PAGE_NAME);

        setPageComplete(false);
    }

    /** *//**
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.dialogs.IDialogPage#createControl(org.eclipse.swt.widgets.Composite)
     */
    public void createControl(Composite parent) ...{
        // create the top level composite for the dialog area
        Composite comp = new Composite(parent, SWT.NONE);
        GridLayout layout = new GridLayout();
        layout.marginHeight = 10;
        layout.marginWidth = 10;
        layout.verticalSpacing = 10;
        layout.horizontalSpacing = 10;
        comp.setLayout(layout);
        comp.setLayoutData(new GridData(GridData.FILL_BOTH));
        comp.setFont(parent.getFont());

        Label label = new Label(comp, SWT.NONE);
        label.setText(StingIDEMessages.NewWizardDialog_wizardLabel);
        label.setLayoutData(new GridData(GridData.FILL, GridData.CENTER, true,
                false, 1, 1));

        createTreeViewer(comp);

        setTitle(StingIDEMessages.NewWizardDialog_subhead);

        setControl(comp);
    }

    /** *//**
     * 创建树视图
     * 
     * @param comp
     */
    private TreeViewer createTreeViewer(Composite comp) ...{
        TreeViewer viewer = new TreeViewer(comp, SWT.SINGLE | SWT.V_SCROLL
                | SWT.H_SCROLL | SWT.BORDER);
        viewer.getControl().setLayoutData(
                new GridData(GridData.FILL, GridData.FILL, true, true, 1, 1));
        viewer.setContentProvider(new TreeContentProvider());
        viewer.setLabelProvider(new TreeLabelProvider());
        viewer.setSorter(new ViewerSorter() ...{
            /** *//**
             * (non-Javadoc)
             * 
             * @see org.eclipse.jface.viewers.ViewerComparator#category(java.lang.Object)
             */
            @Override
            public int category(Object element) ...{
                return element instanceof IWizardCategory ? 1 : 0;
            }
        });
        IWizardRegistry registry = StingPlugin.getDefault().getWorkbench()
                .getNewWizardRegistry();
        viewer.setInput(registry);
        viewer.addSelectionChangedListener(new ISelectionChangedListener() ...{
            /** *//**
             * (non-Javadoc)
             * 
             * @see org.eclipse.jface.viewers.ISelectionChangedListener#selectionChanged(org.eclipse.jface.viewers.SelectionChangedEvent)
             */
            public void selectionChanged(SelectionChangedEvent event) ...{
                NewObjectWizard parentWizard = (NewObjectWizard) NewObjectWizardPage.this
                        .getWizard();

                IStructuredSelection iss = (IStructuredSelection) event
                        .getSelection();
                if (iss.isEmpty()) ...{
                    setPageComplete(false);
                    setMessage("");
                    parentWizard.setCurrentWizard(null);
                } else ...{
                    Object object = iss.getFirstElement();
                    if (object instanceof IWizardCategory) ...{
                        setPageComplete(false);
                        setMessage("");
                        parentWizard.setCurrentWizard(null);
                    } else ...{
                        setPageComplete(true);
                        IWizardDescriptor descriptor = (IWizardDescriptor) object;
                        setMessage(descriptor.getDescription());
                        try ...{
                            IWizard wizard = descriptor.createWizard();
                            parentWizard.setCurrentWizard(wizard);
                        } catch (CoreException e) ...{
                        }
                    }
                }
            }
        });

        return viewer;
    }

    /** *//**
     * Create at 2007-7-16,下午01:58:17<br>
     * 树内容提供器
     * 
     * @author Brad.Wu
     * @version 1.0
     */
    class TreeContentProvider implements ITreeContentProvider ...{
        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.IStructuredContentProvider#getElements(java.lang.Object)
         */
        public Object[] getElements(Object inputElement) ...{
            Object[] ret = null;

            IWizardRegistry registry = (IWizardRegistry) inputElement;
            IWizardCategory rootCategory = registry.getRootCategory();
            Object[] objects = getChildrenOfCategory(rootCategory);
            IWizardDescriptor[] primaryWizards = registry.getPrimaryWizards();
            if (primaryWizards != null) ...{
                ret = new Object[primaryWizards.length + objects.length];
                System.arraycopy(primaryWizards, 0, ret, 0,
                        primaryWizards.length);
                System.arraycopy(objects, 0, ret, primaryWizards.length,
                        objects.length);
            } else ...{
                ret = objects;
            }

            return ret;
        }

        /** *//**
         * 获取指定分类的所有儿子
         * 
         * @param category
         * @return
         */
        private Object[] getChildrenOfCategory(IWizardCategory category) ...{
            IWizardDescriptor[] descs = category.getWizards();
            IWizardCategory[] categories = category.getCategories();

            // 过滤掉不需要的向导和向导分类
            List<Object> list = new ArrayList<Object>();
            if (descs != null) ...{
                for (IWizardDescriptor wizard : descs) ...{
                    list.add(wizard);
                }
            }
            if (categories != null) ...{
                for (IWizardCategory wizardCategory : categories) ...{
                    list.add(wizardCategory);
                }
            }
            Object[] objects = new Object[list.size()];
            list.toArray(objects);
            return objects;
        }

        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.IContentProvider#dispose()
         */
        public void dispose() ...{
        }

        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer,
         *      java.lang.Object, java.lang.Object)
         */
        public void inputChanged(Viewer viewer, Object oldInput, Object newInput) ...{
        }

        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.ITreeContentProvider#getChildren(java.lang.Object)
         */
        public Object[] getChildren(Object parentElement) ...{
            if (parentElement instanceof IWizardCategory) ...{
                return getChildrenOfCategory((IWizardCategory) parentElement);
            } else ...{
                return CommonConstants.EMPTY_OBJECTS;
            }
        }

        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.ITreeContentProvider#getParent(java.lang.Object)
         */
        public Object getParent(Object element) ...{
            if (element instanceof IWizardCategory) ...{
                return ((IWizardCategory) element).getParent();
            } else ...{
                return ((IWizardDescriptor) element).getCategory();
            }
        }

        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.ITreeContentProvider#hasChildren(java.lang.Object)
         */
        public boolean hasChildren(Object element) ...{
            if (element instanceof IWizardCategory) ...{
                IWizardDescriptor[] descs = ((IWizardCategory) element)
                        .getWizards();
                IWizardCategory[] categories = ((IWizardCategory) element)
                        .getCategories();
                return (descs != null && descs.length != 0)
                        || (categories != null && categories.length != 0);
            } else ...{
                return false;
            }
        }
    }

    /** *//**
     * Create at 2007-7-16,下午02:18:12<br>
     * 树标签提供器
     * 
     * @author Brad.Wu
     * @version 1.0
     */
    public class TreeLabelProvider extends LabelProvider ...{
        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.LabelProvider#getImage(java.lang.Object)
         */
        @Override
        public Image getImage(Object element) ...{
            if (element instanceof IWizardCategory) ...{
                return StingPlugin.getImageDescriptor(
                        "icons/objects/folder.gif").createImage();
            } else ...{
                IWizardDescriptor desc = (IWizardDescriptor) element;
                if (desc.getImageDescriptor() != null)
                    return desc.getImageDescriptor().createImage();
                return null;
            }
        }

        /** *//**
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.LabelProvider#getText(java.lang.Object)
         */
        @Override
        public String getText(Object element) ...{
            if (element instanceof IWizardCategory) ...{
                return ((IWizardCategory) element).getLabel();
            } else ...{
                return ((IWizardDescriptor) element).getLabel();
            }
        }
    }
}

这是WizardPage, 也是NewObjectWizard里面唯一的页面. 树是通过读取IWizardRegistry来构造的. 每个叶子节点实际上都是一个Wizard.

这样就行了, 个人认为还是比较简单的. 但是可以肯定的是Eclipse不是这么做的...... 我看不懂, 如果哪位大哥知道真相还请指点一下.

另, 这个可能在RCP当中会用到的吧. 如果仅仅是Plugin的话也不用这么复杂, 声明好Wizard就行了.