如何更改特定視圖上導航欄的顏色

Question

我只需要在某些特定視圖上更改導航欄的顏色。 關於修改導航欄顏色的討論很多，比如https://stackoverflow.com/a/18870519/938380，但它們都改變了同一導航層次結構下每個視圖的導航欄顏色。

我想改變具體意見顏色，並保持其他意見相同的顏色。我如何實現這一目標？

Answer 1

如果您使用標準導航欄，則無法執行此操作。但是你可以使用一些作弊;）例如，您可以將此代碼（或像這樣）添加到您的控制器：

- (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 2

可以設置酒吧色調物業navigationController

我希望這個幫你

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

Answer 3

我通過一個擴展的UIViewController處理這種事情。在我的情況下，我想讓選定的導航欄透明。你可以擴展這個來處理顏色。這樣可以將相同的代碼粘貼到多個控制器中。下面的代碼。

從viewWillAppear你叫[self makeNavigationBarTransparent]。從viewWillDisappear撥打電話[self restoreNavigationBar]

對於您的情況，您只需將其擴展爲makeNavigationBarColored即可。

一個選項也是子類UINavigationController來創建一個具有特定顏色的類。在它的實現中使用這個擴展來設置顏色。在你的故事板中，你想要這種顏色的任何控制器都是你的新類類型。然後，你正在從故事板做這一切。

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