熱門精品專業(yè)原來跟ContributorActionBar有關(guān),在插件中,對(duì)于Editor(這里的Editor是指的多頁編輯器外面的那個(gè)總的Editor不是里面每一頁中的Editor)來說,我們必須為其指定一個(gè)ContributorActionBar,在該類的初始化方法:
void org.eclipse.ui.part.EditorActionBarContributor.init(IActionBars bars)
中需要為IActionBars添加各種Action,比如CopyAction, DeleteAction, CutAction這里面就包括RedoAction和UndoAction,例如在
void org.eclipse.emf.edit.ui.action.EditingDomainActionBarContributor.init(IActionBars actionBars)中就是這樣來做的:
- deleteAction = new DeleteAction(removeAllReferencesOnDelete());
- deleteAction.setImageDescriptor(sharedImages.getImageDescriptor(ISharedImages.IMG_TOOL_DELETE));
- actionBars.setGlobalActionHandler(ActionFactory.DELETE.getId(), deleteAction);
上面的代碼將系統(tǒng)的Undo&Redo快捷鍵以及Eclipse菜單項(xiàng)Delete與deleteAction關(guān)聯(lián)起來了.
如果多頁編輯器里面使用了一個(gè)另外一個(gè)TextEditor,那么在這個(gè)TextEditor中對(duì)Redo&Undo Action會(huì)調(diào)用org.eclipse.ui.texteditor.AbstractTextEditor.createUndoRedoActions()方法,其中代碼如下:
- IUndoContext undoContext= getUndoContext();
- if (undoContext != null) {
- // Use actions provided by global undo/redo
- // Create the undo action
- OperationHistoryActionHandler undoAction= new UndoActionHandler(getEditorSite(), undoContext);
- PlatformUI.getWorkbench().getHelpSystem().setHelp(undoAction, IAbstractTextEditorHelpContextIds.UNDO_ACTION);
- undoAction.setActionDefinitionId(IWorkbenchActionDefinitionIds.UNDO);
- registerUndoRedoAction(ITextEditorActionConstants.UNDO, undoAction);
- ... ...
在registerUndoRedoAction方法中:
- private void registerUndoRedoAction(String actionId, OperationHistoryActionHandler action) {
- IAction oldAction= getAction(actionId);
- if (oldAction instanceof OperationHistoryActionHandler)
- ((OperationHistoryActionHandler)oldAction).dispose();
- setAction(actionId, action);
- IActionBars actionBars= getEditorSite().getActionBars();
- if (actionBars != null)
- actionBars.setGlobalActionHandler(actionId, action);
- }
會(huì)再一次的將指定的Action與全局ActionId關(guān)聯(lián)起來,這樣我們前面制定的Action就會(huì)被屏蔽掉,導(dǎo)致使用了TextEditor的UndoManager之后,EMF的模型編輯的Redo&Undo無法使用,找到了問題所在,至于解決辦法就好搞定了.
另:
研究Undo&Redo的入口在void org.eclipse.swt.custom.StyledText.modifyContent(Event event, boolean updateCaret)
然后是void org.eclipse.swt.custom.StyledTextContent.replaceTextRange(int start, int replaceLength, String text)
StyledTextContent這個(gè)類是用來鏈接TextViewer和Document之間的適配器,TextViewer默認(rèn)的實(shí)現(xiàn)是DefaultDocumentAdapter,如果需要提供自己的DocumentAdapter的實(shí)現(xiàn)需要復(fù)寫 TextViewer 的 createDocumentAdapter() 方法,所有的操作會(huì)轉(zhuǎn)交給當(dāng)前編輯的Document,對(duì)于UndoMananger來說,它會(huì)在每個(gè)TextViewer上所編輯的Document注冊(cè)一些監(jiān)聽器,用來監(jiān)聽Document的改變,當(dāng)Document發(fā)生改變的時(shí)候,會(huì)觸發(fā)這些監(jiān)聽器,這些監(jiān)聽器,根據(jù)Document的改變生成一個(gè)一個(gè)的Command或者Operation并保存在StackCommand或者是History中,以便Undo的時(shí)候從StackCommand和History中取出來執(zhí)行
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