acquireDynamicShapes acquireDynamicShapesArray acquireFrontDoc acquireFrontDoc acquireFrontDocs acquireGraphics addImageShape addImageShape addRef addShapesForTest backDoc backShapes calcPenWidth canRedo canUndo clear clearCachedData createMagnifierView createMagnifierView_ createView createView_ destoryView displayToModel doContextAction drawAll drawAll drawAll drawAll drawAppend drawAppend dynDraw dynDraw dynDraw exportSVG exportSVG exportSVGPath findShapeByImageID findShapeByTag freeContent getBoundingBox getBoundingBox getBoundingBox getChangeCount getCommand getContent getContext getDisplayExtent getDisplayExtent getDrawCount getFrameFlags getFrameIndex getFrameTick getGestureState getGestureType getHandlePoint getImageSize getModelBox getModelBox getRecordTick getRedoCount getRedoIndex getSelectedHandle getSelectedShapeCount getSelectedShapeID getSelectedShapeIDs getSelectedShapeType getShapeCount getShapeCount getShapeFlag getSkipDrawIds getUnlockedShapeCount getVersion getViewModelBox getVisibleShapeCount GiCoreView GiCoreView hasImageShape impl importSVGPath isCommand isDrawing isDrawingCommand isPaused isPlaying isPressDragging isRecording isStopping isUndoLoading isUndoRecording isZoomEnabled isZooming loadFromFile loadShapes onGesture onPause onResume onSize recordShapes recordShapes redo refcount release releaseDocs releaseGraphics releaseShapesArray restoreRecord saveShapes saveToFile setBkColor setCommand setContent setContext setContext setContextEditing setGestureVelocity setOptionBool setOptionFloat setOptionInt setOptionString setPenWidthRange setScreenDpi setSelectedShapeIDs setShapeFlag setViewScaleRange setZoomEnabled startRecord stopDrawing stopRecord submitBackDoc submitDynamicShapes switchCommand traverseImageShapes traverseOptions twoFingersMove undo viewAdapterHandle viewDataHandle zoomPan zoomToExtent zoomToInitial zoomToModel ~GiCoreView

canUndo() bool GiCoreView::canUndo ( ) const virtual 能否撤销 实现了 MgCoreView. 函数调用图: