Question

我只需要在某些特定视图上更改导航栏的颜色。有很多关于修改导航栏颜色的讨论，比如https://stackoverflow.com/a/18870519/938380，但它们都改变了同一导航层次结构下每个视图的导航栏颜色。

我想更改 特定视图 的颜色，并保持其他视图的颜色相同。我如何实现这一目标？

Answer 1

Swift 4 使用

override func willMove(toParentViewController parent: UIViewController?) {
    self.navigationController?.navigationBar.barTintColor = .red
}

它提供了更清晰的动画

Answer 2

如果您使用标准导航栏，则无法执行此操作。但你可以使用一些作弊;）例如，你可以将这个代码（或类似的东西）添加到你的控制器：

 - (void)viewDidAppear:(BOOL)animated {
     [super viewDidAppear:animated];
     oldColor = self.navigationController.navigationBar.backgroundColor;//probably barTintColor instead of backgroundColor
     self.navigationController.navigationBar.backgroundColor = [UIColor yellowColor];
 }
 - (void)viewWillDisappear:(BOOL)animated {
     [super viewWillDisappear:animated];
     self.navigationController.navigationBar.backgroundColor = oldColor;
 }

Answer 3

您可以设置导航控制器的条形色调属性

我希望这个帮助你

[self.navigationController.navigationBar setBarTintColor：[UIColor redColor]];

Answer 4

我通过对UIViewController的扩展来处理这种事情。在我的情况下，我想让选定的导航栏透明。你可以扩展它来处理颜色。这样可以节省在多个控制器中粘贴相同的代码。代码如下。

从viewWillAppear致电[self makeNavigationBarTransparent]。从viewWillDisappear开始，您拨打[self restoreNavigationBar]

对于您的情况，您只需将其扩展为添加makeNavigationBarColored。

选项也是子类UINavigationController，以创建具有特定颜色的类。在其实现中使用此扩展来设置颜色。在你的故事板中，让你想要的任何控制器都是你的新类型。然后你从故事板上做这一切。

的UIViewController + TransparentNavigationBar.h

#import <UIKit/UIKit.h>

@interface UIViewController (TransparentNavigationBar)

/** Makes the current navigation bar transparent and returns a context holding
 * the original settings.
 */
- (void) makeNavigationBarTransparent;

/**
 * Restores the current navigation bar to its original settings.
 */
- (void) restoreNavigationBar;

@end

的UIViewController + TransparentNavigationController.m

#import "UIViewController+TransparentNavigationBar.h"
#import <objc/runtime.h>

@interface VSSNavigationBarContext:NSObject

/** Backup of nav bar image used to restore on push. */
@property UIImage *originalNavBarBackgroundImage;
/** Backup of nav bar shadow image used to restore on push. */
@property UIImage *originalNavBarShadowImage;
/** Backup of nav bar color used to restore on push. */
@property UIColor *originalNavBarColour;

@end

@implementation VSSNavigationBarContext

- (id) init {
    self=[super init];
    if (self){
        self.originalNavBarBackgroundImage=nil;
        self.originalNavBarShadowImage=nil;
        self.originalNavBarColour=nil;
    }
    return self;
}

@end

static char const * const ObjectTagKey = "NavBarContextTag";

@implementation UIViewController (TransparentNavigationBar)

- (VSSNavigationBarContext *) getContext
{
    VSSNavigationBarContext *context=(VSSNavigationBarContext *)objc_getAssociatedObject(self, &ObjectTagKey);
    return context;
}

- (void) makeNavigationBarTransparent{
    VSSNavigationBarContext *context=(VSSNavigationBarContext *)objc_getAssociatedObject(self, &ObjectTagKey);
    if (context == nil){
        context=[[VSSNavigationBarContext alloc] init];

        context.originalNavBarBackgroundImage=[self.navigationController.navigationBar backgroundImageForBarMetrics:UIBarMetricsDefault];
        context.originalNavBarShadowImage=self.navigationController.navigationBar.shadowImage;
        context.originalNavBarColour=self.navigationController.view.backgroundColor;

        // Store the original settings
        objc_setAssociatedObject(self, &ObjectTagKey, context, OBJC_ASSOCIATION_RETAIN);
    }

    //
    // Make transparent
    //
    [self.navigationController.navigationBar setBackgroundImage:[UIImage new]
                                                  forBarMetrics:UIBarMetricsDefault];
    self.navigationController.navigationBar.shadowImage = [UIImage new];
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0f){
        self.navigationController.navigationBar.translucent = YES;
    }
    else{
        self.navigationController.navigationBar.translucent = NO;
    }
    self.navigationController.view.backgroundColor = [UIColor clearColor];
}

- (void) restoreNavigationBar
{
    VSSNavigationBarContext *context=(VSSNavigationBarContext *)objc_getAssociatedObject(self, &ObjectTagKey);
    if (context != nil){
        // Restore original
        [self.navigationController.navigationBar setBackgroundImage:context.originalNavBarBackgroundImage forBarMetrics:UIBarMetricsDefault];
        self.navigationController.navigationBar.shadowImage = context.originalNavBarShadowImage;
        if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0f){
            self.navigationController.navigationBar.translucent = YES;
        }
        else{
            self.navigationController.navigationBar.translucent = NO;
        }
        self.navigationController.view.backgroundColor = context.originalNavBarColour;
    }
}

@end

如何更改特定视图上导航栏的颜色

4 个答案: