NSButton控件用来创建功能按钮，和UIButton相比，其样式要丰富许多。NSButton继承自NSControl，其使用setTarget与setAction来添加触发方法，如下：
NSButton * btn = [[NSButton alloc]initWithFrame:CGRectMake(50, 300, 90, 25)];
[btn setTarget:self];
[btn setAction:@selector(click)];
[self.view addSubview:btn];NSButton类中常用属性和方法解析如下:
//设置按钮标题
@property (copy) NSString *title;
//设置按钮开启状态的标题
@property (copy) NSString *alternateTitle;
//设置按钮图片
@property (nullable, strong) NSImage *image;
//设置按钮开启状态图片
@property (nullable, strong) NSImage *alternateImage;
//设置按钮图片位置
/*
typedef NS_ENUM(NSUInteger, NSCellImagePosition) {
NSNoImage = 0, //无图片
NSImageOnly = 1, //只有图片
NSImageLeft = 2, //图片在左侧
NSImageRight = 3, //图片在右侧
NSImageBelow = 4, //图片在下侧
NSImageAbove = 5, //图片在上侧
NSImageOverlaps = 6, //图片重叠
NSImageLeading API_AVAILABLE(macosx(10.12)) = 7, //正方向
NSImageTrailing API_AVAILABLE(macosx(10.12)) = 8 //逆方向};
*/
@property NSCellImagePosition imagePosition;
//设置图片缩放模式
/*
typedef NS_ENUM(NSUInteger, NSImageScaling) {
NSImageScaleProportionallyDown = 0, // 下方缩放
NSImageScaleAxesIndependently, // 整体缩放
NSImageScaleNone, // 不缩放.
NSImageScaleProportionallyUpOrDown, // 上下缩放
NSScaleProportionally NS_ENUM_DEPRECATED_MAC(10_0, 10_10, "Use NSImageScaleProportionallyDown instead") = 0,
NSScaleToFit NS_ENUM_DEPRECATED_MAC(10_0, 10_10, "Use NSImageScaleAxesIndependently instead"),
NSScaleNone NS_ENUM_DEPRECATED_MAC(10_0, 10_10, "Use NSImageScaleNone instead")};
*/
@property NSImageScaling imageScaling NS_AVAILABLE_MAC(10_5);
//图片是否环绕标题
@property BOOL imageHugsTitle;
//设置按钮状态
/*
enum {
NSMixedState = -1, //混合状态
NSOffState = 0, //关闭状态
NSOnState = 1, //开启状态};
*/
@property NSInteger state;
//设置是否显示边框
@property (getter=isBordered) BOOL bordered;
//设置按钮是否透明
@property (getter=isTransparent) BOOL transparent;
//设置快捷键
@property (copy) NSString *keyEquivalent;
//设置富文本标题
@property (copy) NSAttributedString *attributedTitle;
@property (copy) NSAttributedString *attributedAlternateTitle;
//设置边框风格
@property NSBezelStyle bezelStyle;
//设置是否当鼠标移动到按钮上时显示边框
@property BOOL showsBorderOnlyWhileMouseInside;
//设置按钮声音
@property (nullable, strong) NSSound *sound;
下面是一些便捷创建按钮的方法：
//创建标准的按钮 包括标题和图片
- (instancetype)buttonWithTitle:(NSString )title image:(NSImage )image target:(nullable id)target action:(nullable SEL)action;
//创建文字按钮
- (instancetype)buttonWithTitle:(NSString *)title target:(nullable id)target action:(nullable SEL)action;
//创建图片按钮
- (instancetype)buttonWithImage:(NSImage *)image target:(nullable id)target action:(nullable SEL)action;
//创建复选框按钮
- (instancetype)checkboxWithTitle:(NSString *)title target:(nullable id)target action:(nullable SEL)action;
//创建单选框按钮
- (instancetype)radioButtonWithTitle:(NSString *)title target:(nullable id)target action:(nullable SEL)action;
