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iOS 7 custom back button

I want to use custom back button. in iOS 6 everything is perfect but iOS 7 is strange.

[[UIBarButtonItem appearance] setBackButtonBackgroundImage:[[UIImage imageNamed:@"back_button_normal"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 12.0, 0, 12.0)] forState:UIControlStateNormal barMetrics:UIBarMetricsDefault];

first, it has no iOS 7 arrow and no background image.

(Russian locale)

初始状态

then, if you press the button background image appears. Also i had background image set for UIControlStateHighlighted state and when you hold the button pressed highlighted image appears too. After any back button once pressed all back buttons have background image.

一旦被迫

BUT! If you present modal view controller, dismiss it, then push any view controller - iOS 7 arrow will appear at every back button.

I use DP5. Is that a UIKit bug?

PS Also i tried to create back button manually, using UIBarButtonItem , set background image to it, then self.navigationItem.backBarButtonItem = barButtonItem; Did not help. Then i tried to set background image to disabled state and change enabled property of my bar button item, did not help too.

在此输入图像描述

This is not a bug, this how Back button looks in iOS 7. For example:

在此输入图像描述

You should probably use the new concept for your application, and not to set background image for back button in iOS 7.

If you still want you back button have the same as it looked in iOS6 than you should probably create those back buttons manually:

- (void)loadView
{
    [super loadView];

    UIButton *backButton = [[UIButton alloc] initWithFrame: CGRectMake(0, 0, 60.0f, 30.0f)];
    UIImage *backImage = [[UIImage imageNamed:@"back_button_normal.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 12.0f, 0, 12.0f)];
    [backButton setBackgroundImage:backImage  forState:UIControlStateNormal];
    [backButton setTitle:@"Back" forState:UIControlStateNormal];
    [backButton addTarget:self action:@selector(popBack) forControlEvents:UIControlEventTouchUpInside];
    UIBarButtonItem *backButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
    self.navigationItem.leftBarButtonItem = backButtonItem;
}

-(void) popBack {
  [self.navigationController popViewControllerAnimated:YES];
}

Edit : Not to break Swipe Gesture ( Here is a source)

self.navigationController.interactivePopGestureRecognizer.delegate = (id<UIGestureRecognizerDelegate>)self;

The custom background image not appearing on the first push was fixed in iOS 7 GM.

To hide standard back indicator use this code:

if ([UINavigationBar instancesRespondToSelector:@selector(setBackIndicatorImage:)]) { // iOS 7
    [navigationBarAppearance setBackIndicatorImage:[UIImage imageNamed:@"transparent_1px"]];
    [navigationBarAppearance setBackIndicatorTransitionMaskImage:[UIImage imageNamed:@"transparent_1px"]];
}

The custom background image not appearing initially was not fixed in iOS7 GM or final, as far as I can tell. I see the same problem. It does seem to be an Apple bug; the private view Apple uses simply does not get a setNeedsDisplay call when it needs it on initial display. Doing anything to it which causes that call should fix it -- like pressing on it (which likely changes internal state so it calls setNeedsDisplay on itself), or bringing a modal up (which probably forces a redisplay of the entire view hierarchy on the next viewWillAppear: call).

Using leftBarItems instead also can work, but that may cause a lot of maintenance issues with existing code (some screens may have their own left items, expecting that when set back to nil they restore the original back item, for example).

As mentioned, ideally you would be able to change to a borderless look on iOS7, which means that the bug isn't really apparent (since there is no background image). For some iOS6/iOS7 transition situations though, that may be difficult (lots of screens, and/or the need to support older iOS versions for a while and too hard to have two looks implemented, and it doesn't look good borderless without other changes). If that's the case, the following patch should work:

#import <objc/runtime.h>

@implementation UINavigationBar (BackButtonDisplayFix)

+ (void)load
{
    if ([UIDevice currentDevice].systemVersion.intValue >= 7)
    {
        /*
         * We first try to simply add an override version of didAddSubview: to the class.  If it
         * fails, that means that the class already has its own override implementation of the method
         * (which we are expecting in this case), so use a method-swap version instead.
         */
        Method didAddMethod = class_getInstanceMethod(self, @selector(_displaybugfixsuper_didAddSubview:));
        if (!class_addMethod(self, @selector(didAddSubview:),
                             method_getImplementation(didAddMethod),
                             method_getTypeEncoding(didAddMethod)))
        {
            Method existMethod = class_getInstanceMethod(self, @selector(didAddSubview:));
            Method replacement = class_getInstanceMethod(self, @selector(_displaybugfix_didAddSubview:));
            method_exchangeImplementations(existMethod, replacement);
        }
    }
}

- (void)_displaybugfixsuper_didAddSubview:(UIView *)subview
{
    [super didAddSubview:subview];
    [subview setNeedsDisplay];
}

- (void)_displaybugfix_didAddSubview:(UIView *)subview
{
    [self _displaybugfix_didAddSubview:subview]; // calls the existing method
    [subview setNeedsDisplay];
}

@end

Note: UINavigationBar does currently have an override of the method in question, so I'd expect the method_exchangeImplementations style to be used. I just added the other stuff for safety in case Apple changes their code. We may go borderless ourselves, but I did find this approach worked as an option (until a more thorough UI uplift), at least.

Additional note: This bug appears to be fixed in iOS 7.1. So, the patch could be conditionalized to only install the methods if running >= 7.0 and < 7.1.

There is a better solution that doesn't involve method swizzling.

You need to add UINavigationViewControllerDelegate method somewhere in your app.

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
dispatch_async(dispatch_get_main_queue(), ^{
    [[navigationController.navigationBar subviews] makeObjectsPerformSelector:@selector(setNeedsDisplay)];
});

}

My solution is for iOS 7 and above.

At first, make default back button invisible.

self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"" style:UIBarButtonItemStylePlain target:nil action:nil];

then, set default backIndicatorImage of back button using custom image.

[UINavigationBar appearance].backIndicatorImage = [[UIImage imageNamed:@"topbar_icon_back_n.png"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
[UINavigationBar appearance].backIndicatorTransitionMaskImage = [[UIImage imageNamed:@"topbar_icon_back_p.png"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

At this point, make custom UINavigationBar for resizing _UINavigationBarBackIndicatorView which contains above backIndicatorImage .

const CGPoint SANavigationBarOffset = {-8, 11.5};

@implementation SANavigationBar

- (void)layoutSubviews
{
    [super layoutSubviews];

    // set back button position
    NSArray *classNamesToReposition = @[@"_UINavigationBarBackIndicatorView"];

    for (UIView *view in [self subviews]) {
        if ([classNamesToReposition containsObject:NSStringFromClass([view class])]) {
            CGRect frame = [view frame];
            frame.origin.x = 0;
            frame.origin.y = 0;

            [view setFrame:frame];
        }
    }
}

@end

then, set it as my navigationBar

// set custom NavagationBar for back button position
[self.navigationController setValue:[[SANavigationBar alloc] init] forKey:@"navigationBar"];

Add button as navigation item in ios7 as below

 UIButton *btnAdd = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 60, 30)];

        [btnAdd setContentMode:UIViewContentModeScaleAspectFit];

        [btnAdd setBackgroundImage:[UIImage imageNamed:@"back.png"] forState:UIControlStateNormal];

        [btnAdd addTarget:self action:@selector(backButtonPressed:) forControlEvents:UIControlEventTouchUpInside];

        UIBarButtonItem *btnAdd = [[UIBarButtonItem alloc] initWithCustomView:imView];

        self.navigationItem.rightBarButtonItem = btnAdd;

Using Swift you can just add a extension:

extension UIViewController: UIGestureRecognizerDelegate {
    func popBack() {
        self.navigationController?.popViewControllerAnimated(true)
    }

    func enableCustomBackButtom() {
        self.navigationItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(named: "icon-back"), style: UIBarButtonItemStyle.Plain, target: self, action:"popBack")

        self.navigationController?.interactivePopGestureRecognizer.delegate = self
    }
}

And in your UIViewController use like this:

self.enableCustomBackButtom()

I just did it providing the same behaviour as in iOS6 (notice that navigationBar is the UINavigationBar), make sure that navigationBar has a topItem

UINavigationItem *topItemNavigation = [navigationBar topItem];

UIBarButtonItem *barButtonTopItemNavigation = [[UIBarButtonItem alloc] initWithTitle:topItemNavigation.title style:UIBarButtonItemStyleBordered target:nil action:nil];

[barButtonTopItemNavigation setBackButtonBackgroundImage:YOUR_IMAGE_BACKGROUND forState:UIControlStateNormal barMetrics:UIBarMetricsDefault ];
            [topItemNavigation setBackBarButtonItem: barButtonTopItemNavigation];
        }

My solution was to write a category on UINavigationItem. This is for iOS7.

- (void)mdSetCustomBackButton:(UINavigationController *)navigationController
{
    MDBackButton *backButton = [[MDBackButton alloc] initWithFrame:CGRectMake(0.0, 0.0, 44.0, 44.0) navigationController:navigationController];
    [backButton addTarget:self action:@selector(popBack:) forControlEvents:UIControlEventTouchUpInside];
    UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
    [self setLeftBarButtonItem:barButtonItem];
    [navigationController.interactivePopGestureRecognizer setDelegate:(id<UIGestureRecognizerDelegate>)self];
}

- (void)popBack:(MDBackButton *)sender
{
    [sender.navigationController popViewControllerAnimated:YES];
}

And subclass UIButton to add a UINavigationController property (to pop and set swipe back delegate).

@property (nonatomic, weak) UINavigationController *navigationController;

@implementation MDBackButton

- (id)initWithFrame:(CGRect)frame navigationController:(UINavigationController *)navigationController
{
    self = [super initWithFrame:frame];
    if(self){
        _navigationController = navigationController;
        [self setImage:[UIImage imageNamed:@"back_button"] forState:UIControlStateNormal];
    }
    return self;
}

This is work for me:

- (void)setCustomNavigationBackButton
{    
  self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"" style:UIBarButtonItemStylePlain target:nil action:nil];

  UIImage *myIcon = [self imageWithImage:[UIImage imageNamed:@"backbutton.png"] scaledToSize:CGSizeMake(20, 20)];

  self.navigationController.navigationBar.backIndicatorImage = myIcon;
  self.navigationController.navigationBar.backIndicatorTransitionMaskImage = myIcon;
}

- (UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize 
{
  //UIGraphicsBeginImageContext(newSize);
  // In next line, pass 0.0 to use the current device's pixel scaling factor (and thus account for Retina resolution).
  // Pass 1.0 to force exact pixel size.
  UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
  [image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
  UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();
  return newImage;
}

Also, custom font with custom color:

//self.navigationController.navigationBar.tintColor = [UIColor whiteColor];

[[UIBarButtonItem appearanceWhenContainedIn:[UINavigationBar class], nil] setTitleTextAttributes:
 @{NSForegroundColorAttributeName:[UIColor whiteColor],
   NSFontAttributeName:[UIFont fontWithName:@"Signika-Bold" size:20]}

forState:UIControlStateNormal];

Reference: https://stackoverflow.com/a/2658801/1371949

I use these codes below, which works in iOS 8

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.translatesAutoresizingMaskIntoConstraints = NO;
button.exclusiveTouch = YES;
button.titleLabel.font = [UIFont systemFontOfSize:14.0];
[button setTitleColor:kWhiteColor forState:UIControlStateNormal];
[button setTitleColor:[UIColor colorWithRed:1/255.0 green:36/255.0 blue:60/255.0 alpha:1.0] forState:UIControlStateHighlighted];
[button setTitle:@"Back" forState:UIControlStateNormal];
[button setImage:[UIImage imageNamed:@"barbutton_back"] forState:UIControlStateNormal];
[button setImageEdgeInsets:UIEdgeInsetsMake(1.0, 0.0, 0.0, 0.0)];
CGSize fontSize = [button.titleLabel sizeThatFits:CGSizeMake(100.0, 30.0)];
button.frame = CGRectMake(0.0, 0.0, button.imageView.image.size.width+fontSize.width, 30.0);
UIBarButtonItem *barbtn = [[UIBarButtonItem alloc] initWithCustomView:button];
//fix iOS 7 left margin
UIBarButtonItem *negativeSpacer = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
negativeSpacer.width = -10;
self.navigationItem.leftBarButtonItems = [NSArray arrayWithObjects:negativeSpacer,barbtn, nil];
-(void) viewWillAppear:(BOOL)animated
{
    UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
    [btn setFrame:CGRectMake(0, 0, 30, 44)];
    [btn setImage:[UIImage imageNamed:@"btnBack.png"] forState:UIControlStateNormal];
    [btn addTarget:self action:@selector(PopToView) forControlEvents:UIControlEventTouchUpInside];
    UIBarButtonItem *btnBack = [[UIBarButtonItem alloc] initWithCustomView:btn];
    [btnBack setTintColor:[UIColor whiteColor]];
    [[self.navigationController navigationItem] setLeftBarButtonItem:btnBack];

}

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