相信所有试着使用自定义返回的leftItem，但是也会发现一个问题就是ios7.0的那个pan返回上一页的手势失效了。
因为自己使用app的时候是7.0的系统，所以呢，觉得相当的不爽，于是纠结了，然后到stackoverflow.com里面找到相关的资料，但是各种try,各种bug，最后，综合所有的方法。
嗯，好吧，最后还是采用网上的一个放，继承UINavgationViewController，然后派生对应方法。
于是，使用这个代码在你的工程里就OK，暂时未发现BUG。标记:
CBNavigationController.h
#import <UIKit/UIKit.h>
@interface CBNavigationController : UINavigationController <UINavigationControllerDelegate, UIGestureRecognizerDelegate>
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated;
- (NSArray *)popToViewController:(UIViewController *)viewController animated:(BOOL)animated;
- (NSArray *)popToRootViewControllerAnimated:(BOOL)animated;
@end
#import "CBNavigationController.h"
CBNavigationController.m
@implementation CBNavigationController
- (void)viewDidLoad
{
__weakCBNavigationController *weakSelf = self;
if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)])
{
self.interactivePopGestureRecognizer.delegate = weakSelf;
self.delegate = weakSelf;
}
}
// Hijack the push method to disable the gesture
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)]&&animated==YES)
self.interactivePopGestureRecognizer.enabled = NO;
[super pushViewController:viewController animated:animated];
}
- (NSArray *)popToRootViewControllerAnimated:(BOOL)animated
{
if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)]&&animated==YES)
self.interactivePopGestureRecognizer.enabled = NO;
return [superpopToRootViewControllerAnimated:animated];
}
- (NSArray *)popToViewController:(UIViewController *)viewController animated:(BOOL)animated
{
if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)])
self.interactivePopGestureRecognizer.enabled = NO;
return [super popToViewController:viewController animated:animated];
}
#pragma mark UINavigationControllerDelegate
- (void)navigationController:(UINavigationController *)navigationController
didShowViewController:(UIViewController *)viewController
animated:(BOOL)animate
{
// Enable the gesture again once the new controller is shown
if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)]){
self.interactivePopGestureRecognizer.enabled = YES;
}
}
-(BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
if (gestureRecognizer==self.interactivePopGestureRecognizer) {
if (self.viewControllers.count<2||self.visibleViewController==[self.viewControllersobjectAtIndex:0]) {
return NO;
}
}
returnYES;
}
@end