- 页面消失的时候
- (void)viewWillDisappear:(BOOL)animated {
NSArray *viewControllers = self.navigationController.viewControllers;//获取当前的视图控制其
if (viewControllers.count > 1 && [viewControllers objectAtIndex:viewControllers.count-2] == self) {
//当前视图控制器在栈中，故为push操作
NSLog(@"push");
} else if ([viewControllers indexOfObject:self] == NSNotFound) {
//当前视图控制器不在栈中，故为pop操作
NSLog(@"pop");
}
}
