UINavigationController 的 setViewControllers 方法

在 iOS 开发中，UINavigationController 是很常用的 Controller，对它的一般操作就像操作一个栈，push 和 pop。但也经常会遇到 pop 和 push 无法优雅的完成的操作，比如退回到中间的某个 VC 上，或者在第一个 VC 之前添加一个 VC 等，更甚者要重新构造整个 VC 的顺序，这时候 setViewControllers 方法就排上用场了，它使对 VC 栈的操作不再局限于 push 和 pop，而是构造整个 VC 栈并应用到当前的 UINavigationController 中，这个方法支持 iOS3.0+，放心使用。


#Sample

NSMutableArray * viewControllers = [self.navigationController.viewControllers mutableCopy];
[viewControllers removeLastObject];
[viewControllers addObject:newController];

[self.navigationController setViewControllers:viewControllers animated:YES];
// [viewControllers relase] // if non-arc

感谢 Allen (Weibo) 提供的代码和思路




#说明
下面这段摘自 Api 文档

You can use this method to update or replace the current view controller stack without pushing or popping each controller explicitly. In addition, this method lets you update the set of controllers without animating the changes, which might be appropriate at launch time when you want to return the navigation controller to a previous state.

If animations are enabled, this method decides which type of transition to perform based on whether the last item in the items array is already in the navigation stack. 

1.If the view controller is currently in the stack, but is not the topmost item, this method uses a pop transition; 
2.if it is the topmost item, no transition is performed. 
3.If the view controller is not on the stack, this method uses a push transition. 

Only one transition is performed, but when that transition finishes, the entire contents of the stack are replaced with the new view controllers. For example, if controllers A, B, and C are on the stack and you set controllers D, A, and B, this method uses a pop transition and the resulting stack contains the controllers D, A, and B.

Have fun！