iOS 7 navigationBar重新定位后dismissViewController

Question

我有一个嵌入导航控制器的控制器。假设我有一个重新定位self.navigationController.navigationBar的按钮。然后，我用任何控制器（不管是否导航都无关紧要）呈现ViewControllerAnimated，并在解散导航栏后返回其原始位置（实际上它在关闭动画开始时处于原始位置）。在iOS 6和更早版本中，栏不会自动重新定位。任何想法如何防止iOS 7中重新定位？

Answer 1

好的，所以我终于明白了。

首先 - 苹果不希望我们改变UINavigationBar的位置。因此，你应该不惜一切代价避免它。在我的情况下，我有一个应用程序来解决它移动UINavigationBar显示滑出菜单。滑出菜单问题的正确解决方案是将UINavigationController 放入之内 - 然后您可以将整个UINavigationController与其内容（无论它是什么内容）滑动并且一切正常。出于某种原因，UINavigationController在此应用程序之外。所以，我不得不求助于黑客。如果您有任何选择不使用此方法，请勿使用此方法。这是一个黑客攻击，它可能会在更多的iOS版本中破解，Apple肯定不会感激它。

首先，在iOS7探索新的过渡系统：http://www.doubleencore.com/2013/09/ios-7-custom-transitions/

然后，替换：

[self presentViewController:navigationController animated:YES completion:nil]; 

与

if([UIApplication iOS7]) /* or any other custom iOS7 detection method you implement */ 
{ /* we simulate old transition with nav bar slided out */ 
    navigationController.transitioningDelegate = [OMModalTransitionDelegate new]; 
} 

[self presentViewController:navigationController animated:YES completion:nil]; 

所以，我们需要一个过渡的委托来模拟标准的行为和做还有技巧。

#import "OMModalTransitionDelegate.h" 
#import "OMAnimatedTransitioning.h" 

@implementation OMModalTransitionDelegate 

- (id <UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source 
{ 
    OMAnimatedTransitioning *transitioning = [OMAnimatedTransitioning new]; 
    return transitioning; 
} 

- (id <UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController *)dismissed 
{ 
    OMAnimatedTransitioning *transitioning = [OMAnimatedTransitioning new]; 
    transitioning.reverse = YES; 
    return transitioning; 
} 

@end 

而现在的实际动画管理器（你有在自己UINavigationBar的一个类别来实现sharedBar）：

static NSTimeInterval const DEAnimatedTransitionDuration = 0.4f; 
static NSTimeInterval const DEAnimatedTransitionMarcoDuration = 0.15f; 


@implementation OMAnimatedTransitioning 


- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext 
{ 
    UIViewController *fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey]; 
    UIViewController *toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey]; 
    UIView *container = [transitionContext containerView]; 
    UIView *superView = [UINavigationBar sharedBar].superview; 
    CGRect barFrame = [UINavigationBar sharedBar].frame; 
    if(self.reverse) 
    { /* Trick - first, remove the bar from it's superview before animation starts */ 
    [[UINavigationBar sharedBar] removeFromSuperview]; 
    } 
    CGRect oldFrame = container.bounds; 
    if (self.reverse) 
    { 
    [container insertSubview:toViewController.view belowSubview:fromViewController.view]; 
    } 
    else 
    { 
    toViewController.view.frame = oldFrame; 
    toViewController.view.transform = CGAffineTransformMakeTranslation(0, CGRectGetHeight(oldFrame)); 
    [container addSubview:toViewController.view]; 
    } 

[UIView animateKeyframesWithDuration:DEAnimatedTransitionDuration delay:0 options:0 animations:^ 
{ 
    if (self.reverse) 
    { 
    fromViewController.view.transform = CGAffineTransformMakeTranslation(0, CGRectGetHeight(oldFrame)); 
    double delayInSeconds = 0.01; /* Trick - after an imperceivable delay - add it back - now it is immune to whatever Apple put there to move it */ 
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC)); 
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void) 
    { 
     [UINavigationBar sharedBar].frame = barFrame; 
     [superView addSubview:[UINavigationBar sharedBar]]; 
    }); 

    } 
    else 
    { 
    toViewController.view.transform = CGAffineTransformIdentity; 
    } 
} completion:^(BOOL finished) { 


    [transitionContext completeTransition:finished]; 
}]; 
} 

- (NSTimeInterval)transitionDuration:(id<UIViewControllerContextTransitioning>)transitionContext 
{ 
    return DEAnimatedTransitionDuration; 
} 
@end 

Answer 2

在您的自定义导航控制器，加

- (void)viewWillLayoutSubviews { 
    //do your navigation bar layout 
} 

希望这可以帮助你。提醒，以上方法只支持ios> = 5.0。