解决自定义leftBarButtonItem导致UINavigationController侧滑失效或卡住

今天看了看自己以前做的项目，发现和其他应用在界面返回的地方不太一样，就是不支持侧滑。通过上网及自己思考完美解决。

要支持侧滑，需要我们自定义UINavigationConroller

贴下代码：

@interface JFNavigationController ()

@end

@implementation JFNavigationController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    __weak JFNavigationController *weakSelf = self;
    if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)])
    {
        self.interactivePopGestureRecognizer.delegate = weakSelf;
        self.delegate = weakSelf;
    }
}

- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated {
    
    if ( [self respondsToSelector:@selector(interactivePopGestureRecognizer)])
    {
        self.interactivePopGestureRecognizer.enabled = NO;
    }
    
    [super pushViewController:viewController animated:animated];
    
}

- (NSArray *)popToRootViewControllerAnimated:(BOOL)animated
{
    if ( [self respondsToSelector:@selector(interactivePopGestureRecognizer)])
    {
        self.interactivePopGestureRecognizer.enabled = NO;
    }
    
    return  [super popToRootViewControllerAnimated: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 {
    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.viewControllers objectAtIndex:0] ) {
            return NO;
        }
    }
    return YES;
}

@end

这样就可以解决手势返回的问题，且不会出现返回卡住UI的bug。

附上Demo地址：
https://github.com/jifengchao/UINavigationController-

借鉴文章：
http://blog.csdn.net/chenyong05314/article/details/44829127