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我想撤消对我的NSManagedObjectContext的保存操作;我一直认为,这是什么NSUndoManager是,但它好像撤消在保存操作不起作用......NSManagedObjectContext:撤消保存操作?
一个例子:
[[NSManagedObjectContext MR_contextForCurrentThread] setUndoManager:[NSUndoManager new]];
[[NSManagedObjectContext MR_contextForCurrentThread].undoManager beginUndoGrouping];
MyDataObject *mdo = [MyDataObject MR_createInContext:[NSManagedObjectContext MR_contextForCurrentThread]];
mdo.name = @"...";
[[NSManagedObjectContext MR_contextForCurrentThread] save:nil];
[[NSManagedObjectContext MR_contextForCurrentThread].undoManager endUndoGrouping];
[[NSManagedObjectContext MR_contextForCurrentThread].undoManager undo];
但插不撤消。 ..有没有办法做到这一点?像交易一样?