详解iOS应用中自定义UIBarButtonItem导航按钮的创建方法

ios系统导航栏中有leftbarbuttonitem和rightbarbuttonitem，我们可以根据自己的需求来自定义这两个uibarbuttonitem。

四种创建方法

系统提供了四种创建的方法：

- (instancetype)initwithbarbuttonsystemitem:(uibarbuttonsystemitem)systemitem target:(id)target action:(sel)action;

- (instancetype)initwithimage:(uiimage *)image style:(uibarbuttonitemstyle)style target:(id)target action:(sel)action;

- (instancetype)initwithtitle:(nsstring *)title style:(uibarbuttonitemstyle)style target:(id)target action:(sel)action;

- (instancetype)initwithbarbuttonsystemitem:(uibarbuttonsystemitem)systemitem target:(id)target action:(sel)action;

- (instancetype)initwithcustomview:(uiview *)customview;

通过系统uibarbuttonsystemitem创建

自定义rightbarbuttonitem，代码如下：

self.navigationitem.rightbarbuttonitem = [[uibarbuttonitem alloc] initwithbarbuttonsystemitem:uibarbuttonsystemitemdone target:self action:@selector(right:)];

uibarbuttonsystemitem有以下样式可以供选择：

typedef ns_enum(nsinteger, uibarbuttonsystemitem) {
    uibarbuttonsystemitemdone,
    uibarbuttonsystemitemcancel,
    uibarbuttonsystemitemedit, 
    uibarbuttonsystemitemsave, 
    uibarbuttonsystemitemadd,
    uibarbuttonsystemitemflexiblespace,
    uibarbuttonsystemitemfixedspace,
    uibarbuttonsystemitemcompose,
    uibarbuttonsystemitemreply,
    uibarbuttonsystemitemaction,
    uibarbuttonsystemitemorganize,
    uibarbuttonsystemitembookmarks,
    uibarbuttonsystemitemsearch,
    uibarbuttonsystemitemrefresh,
    uibarbuttonsystemitemstop,
    uibarbuttonsystemitemcamera,
    uibarbuttonsystemitemtrash,
    uibarbuttonsystemitemplay,
    uibarbuttonsystemitempause,
    uibarbuttonsystemitemrewind,
    uibarbuttonsystemitemfastforward,
#if __iphone_3_0 <= __iphone_os_version_max_allowed
    uibarbuttonsystemitemundo,
    uibarbuttonsystemitemredo,
#endif
#if __iphone_4_0 <= __iphone_os_version_max_allowed
    uibarbuttonsystemitempagecurl,
#endif
};

最后别忘了实现right:方法：

- (void)right:(id)sender
{
    nslog(@"rightbarbuttonitem");
}

自定义文字的uibarbuttonitem

self.navigationitem.leftbarbuttonitem = [[uibarbuttonitem alloc] initwithtitle:@"back" style:uibarbuttonitemstyleplain target:self action:@selector(back:)];
uibarbuttonitemstyle有以下三种选择：

typedef ns_enum(nsinteger, uibarbuttonitemstyle) {
    uibarbuttonitemstyleplain,
    uibarbuttonitemstylebordered ns_enum_deprecated_ios(2_0, 8_0, "use uibarbuttonitemstyleplain when minimum deployment target is ios7 or later"),
    uibarbuttonitemstyledone,
};

实现back:方法：

- (void)back:(id)sender
{
    [self.navigationcontroller popviewcontrolleranimated:yes];
}

自定义照片的uibarbuttonitem

self.navigationitem.rightbarbuttonitem = [[uibarbuttonitem alloc] initwithimage:[uiimage imagenamed:@"test"] style:uibarbuttonitemstyleplain target:self action:@selector(right:)];

自定义uiview的uibarbuttonitem

自定义uiview，然后通过initwithcustomview:方法来创建uibarbuttonitem。

uiview *testview = [[uiview alloc] initwithframe:cgrectmake(0, 0, 40, 60)];
self.navigationitem.rightbarbuttonitem = [[uibarbuttonitem alloc] initwithcustomview:testview];

看到有朋友在后台提问：

我现在即需要改那个导航原生的返回图片，也要改返回文字，应该怎么改呢，求指教。
其实，这个就可以用initwithcustomview:来解决，自定义uiview你可以放uiimageview和uilabel。可以自定义uiview，那么想怎么定义都是可以的。

下面来看一个有趣的例子：
先说一下需求：
1.做一个rightbarbuttonitem不断旋转的demo；
2.点击rightbarbuttonitem 按钮旋转或暂停；
最终效果展示：

就是那个音符图形的旋转。
关键代码展示（已加注释）：

//
// viewcontroller.m
// navigationbtn
//

#import "viewcontroller.h"
#define degrees_to_radians(angle) ((angle) / 180.0 * m_pi)

///imageview旋转状态枚举
typedef enum {
rotatestatestop,
rotatestaterunning,
}rotatestate;

@interface viewcontroller ()
{
///旋转角度
cgfloat imageviewangle;
///旋转imageview
uiimageview *imageview;
///旋转状态
rotatestate rotatestate;
}

@end

@implementation viewcontroller

- (void)viewdidload
{
[super viewdidload];
self.title=@"微信公众账号:乐coding";
[self buildbarbuttonitem];
}
#pragma mark 添加 rightbarbuttonitem
-(void)buildbarbuttonitem{

imageview = [[uiimageview alloc] initwithimage:[uiimage imagenamed:@"icon"]];
imageview.autoresizingmask = uiviewautoresizingnone;
imageview.contentmode = uiviewcontentmodescaletofill;
imageview.bounds=cgrectmake(0, 0, 40, 40);
//设置视图为圆形
imageview.layer.maskstobounds=yes;
imageview.layer.cornerradius=20.f;
uibutton *button = [uibutton buttonwithtype:uibuttontypecustom];
button.frame = cgrectmake(0, 0, 40, 40);
[button addsubview:imageview];
[button addtarget:self action:@selector(animate) forcontrolevents:uicontroleventtouchupinside];
imageview.center = button.center;
//设置rightbarbuttonitem
uibarbuttonitem *baritem = [[uibarbuttonitem alloc] initwithcustomview:button];
self.navigationitem.rightbarbuttonitem = baritem;
}
#pragma mark 点击 rightbarbuttonitem
- (void)animate {
//改变imageview旋转状态
if (rotatestate==rotatestatestop) {
rotatestate=rotatestaterunning;
[self rotateanimate];
}else{
rotatestate=rotatestatestop;
}
}
#pragma mark 旋转动画
-(void)rotateanimate{
imageviewangle+=50;
//0.5秒旋转50度
[uiview animatewithduration:0.5 delay:0.0 options:uiviewanimationoptioncurvelinear animations:^{
imageview.transform = cgaffinetransformmakerotation(degrees_to_radians(imageviewangle));
} completion:^(bool finished) {
if (rotatestate==rotatestaterunning) {
[self rotateanimate];
}
}];
}

- (void)didreceivememorywarning {
[super didreceivememorywarning];
// dispose of any resources that can be recreated.
}

@end