UINavigationBar 一个有样式的view

Posted 2020-06-28 人生路1/5

UINavigationBar 继承自，UIView。你可以把它看为是一个特殊的view。

 

他也是可以独立使用的。

UINavigationBar *bar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0, 414, 80)];
[self.view addSubview:bar];

好下面是 UINavigationBar 的一些属性和方法

 1 //NS_CLASS_AVAILABLE_ios(2_0) @interface UINavigationBar : UIView <NSCoding, UIBarPositioning>
 2 //
 3 //UINavigationBar 的样式
 4 //typedef NS_ENUM(NSInteger, UIBarStyle) {
 5 //    UIBarStyleDefault          = 0,//默认
 6 //    UIBarStyleBlack            = 1,//黑色
 7 //}
 8   @property(nonatomic,assign) UIBarStyle barStyle __TVOS_PROHIBITED;
 9 
10 //代理
11   @property(nullable,nonatomic,weak) id<UINavigationBarDelegate> delegate;
12 //
13 ///*
14 // New behavior on iOS 7.
15 // Default is YES.
16 // You may force an opaque background by setting the property to NO.
17 // If the navigation bar has a custom background image, the default is inferred
18 // from the alpha values of the image—YES if it has any pixel with alpha < 1.0
19 // If you send setTranslucent:YES to a bar with an opaque custom background image
20 // it will apply a system opacity less than 1.0 to the image.
21 // If you send setTranslucent:NO to a bar with a translucent custom background image
22 // it will provide an opaque background for the image using the bar‘s barTintColor if defined, or black
23 // for UIBarStyleBlack or white for UIBarStyleDefault if barTintColor is nil.
24 // */
25 //是否透明
26   @property(nonatomic,assign,getter=isTranslucent) BOOL translucent NS_AVAILABLE_IOS(3_0) UI_APPEARANCE_SELECTOR; // Default is NO on iOS 6 and earlier. Always YES if barStyle is set to UIBarStyleBlackTranslucent
27 //
28 //// Pushing a navigation item displays the item‘s title in the center of the navigation bar.
29 //// The previous top navigation item (if it exists) is displayed as a "back" button on the left.
30 //push一个 Item（UINavigationItem）
31   - (void)pushNavigationItem:(UINavigationItem *)item animated:(BOOL)animated;
32 //pop UINavigationItem
33   - (nullable UINavigationItem *)popNavigationItemAnimated:(BOOL)animated; // Returns the item that was popped.
34 //
35 //当前push到最上层的item
36   @property(nullable, nonatomic,readonly,strong) UINavigationItem *topItem;
37 //仅次于最上层的item，一般式被推向导航栏左侧的item
38   @property(nullable, nonatomic,readonly,strong) UINavigationItem *backItem;
39 //
40 //获取堆栈中所有item的数组
41   @property(nullable,nonatomic,copy) NSArray<UINavigationItem *> *items;
42 //设置一组item
43   - (void)setItems:(nullable NSArray<UINavigationItem *> *)items animated:(BOOL)animated; // If animated is YES, then simulate a push or pop depending on whether the new top item was previously in the stack.
44 //
45 ///*
46 // The behavior of tintColor for bars has changed on iOS 7.0. It no longer affects the bar‘s background
47 // and behaves as described for the tintColor property added to UIView.
48 // To tint the bar‘s background, please use -barTintColor.
49 // */
50 //影响到导航栏上左侧pop按钮的图案颜色和字体颜色
51   @property(null_resettable, nonatomic,strong) UIColor *tintColor;
52 //设置导航栏的背景色，这个属性被设置后，半透明的效果将失效
53   @property(nullable, nonatomic,strong) UIColor *barTintColor NS_AVAILABLE_IOS(7_0) UI_APPEARANCE_SELECTOR;  // default is nil
54 //
55 ///* In general, you should specify a value for the normal state to be used by other states which don‘t have a custom value set.
56 // 
57 // Similarly, when a property is dependent on the bar metrics (on the iPhone in landscape orientation, bars have a different height from standard), be sure to specify a value for UIBarMetricsDefault.
58 // */
59 //
60   - (void)setBackgroundImage:(nullable UIImage *)backgroundImage forBarPosition:(UIBarPosition)barPosition barMetrics:(UIBarMetrics)barMetrics NS_AVAILABLE_IOS(7_0) UI_APPEARANCE_SELECTOR;
61   - (nullable UIImage *)backgroundImageForBarPosition:(UIBarPosition)barPosition barMetrics:(UIBarMetrics)barMetrics NS_AVAILABLE_IOS(7_0) UI_APPEARANCE_SELECTOR;
62 
63 // Same as using UIBarPositionAny in -setBackgroundImage:forBarPosition:barMetrics. Resizable images will be stretched
64 // vertically if necessary when the navigation bar is in the position UIBarPositionTopAttached.
65 // */
66   - (void)setBackgroundImage:(nullable UIImage *)backgroundImage forBarMetrics:(UIBarMetrics)barMetrics NS_AVAILABLE_IOS(5_0) UI_APPEARANCE_SELECTOR;
67   - (nullable UIImage *)backgroundImageForBarMetrics:(UIBarMetrics)barMetrics NS_AVAILABLE_IOS(5_0) UI_APPEARANCE_SELECTOR;
68 //上面两个方法用于设置和获取导航栏的背景图案，这里需要注意，默认背景图案是不做缩放处理的，所以我们使用的图片尺寸要和导航栏尺寸匹配，这里面还有一个UIBarMetrics参数，这个参数设置设备的状态，如下：
69 //typedef NS_ENUM(NSInteger, UIBarMetrics) {
70 //    UIBarMetricsDefault,//正常竖屏状态
71 //    UIBarMetricsCompact,//横屏状态
72 //};
73 //
74 
75 ///* Default is nil. When non-nil, a custom shadow image to show instead of the default shadow image. For a custom shadow to be shown, a custom background image must also be set with -setBackgroundImage:forBarMetrics: (if the default background image is used, the default shadow image will be used).
76 // */
77 //设置导航栏的阴影图片
78   @property(nullable, nonatomic,strong) UIImage *shadowImage NS_AVAILABLE_IOS(6_0) UI_APPEARANCE_SELECTOR;
79 //
80 ///* You may specify the font, text color, and shadow properties for the title in the text attributes dictionary, using the keys found in NSAttributedString.h.
81 // */
82 //设置导航栏的标题字体属性
83 //例如：bar.titleTextAttributes = @{NSForegroundColorAttributeName:[UIColor redColor]};
84   @property(nullable,nonatomic,copy) NSDictionary<NSString *,id> *titleTextAttributes NS_AVAILABLE_IOS(5_0) UI_APPEARANCE_SELECTOR;
85 //
86 //设置导航栏标题的竖直位置偏移
87   - (void)setTitleVerticalPositionAdjustment:(CGFloat)adjustment forBarMetrics:(UIBarMetrics)barMetrics NS_AVAILABLE_IOS(5_0) UI_APPEARANCE_SELECTOR;
88   - (CGFloat)titleVerticalPositionAdjustmentForBarMetrics:(UIBarMetrics)barMetrics NS_AVAILABLE_IOS(5_0) UI_APPEARANCE_SELECTOR;
89 //
90 ///*
91 // The back indicator image is shown beside the back button.
92 // The back indicator transition mask image is used as a mask for content during push and pop transitions
93 // Note: These properties must both be set if you want to customize the back indicator image.
94 // */
95 //返回按钮的样式（这两个一起设置）
96   @property(nullable,nonatomic,strong) UIImage *backIndicatorImage NS_AVAILABLE_IOS(7_0) UI_APPEARANCE_SELECTOR __TVOS_PROHIBITED;
97   @property(nullable,nonatomic,strong) UIImage *backIndicatorTransitionMaskImage NS_AVAILABLE_IOS(7_0) UI_APPEARANCE_SELECTOR __TVOS_PROHIBITED;
98 //
99   @end

UINavigationBarDelegate

1 //item将要push的时候调用，返回NO，则不能push
2 - (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPushItem:(UINavigationItem *)item; 
3 //item已经push后调用
4 - (void)navigationBar:(UINavigationBar *)navigationBar didPushItem:(UINavigationItem *)item; 
5 //item将要pop时调用，返回NO，不能pop  
6 - (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item; 
7 //item已经pop后调用 
8 - (void)navigationBar:(UINavigationBar *)navigationBar didPopItem:(UINavigationItem *)item;

 

bar上是item（UINavigationItem）这不是一个按钮那么简单。它里面承载着 UIBarButtonItem