iOS Tabbar中间添加凸起可旋转按钮功能

//MCTabBarController.m//添加子控制器- (void)addChildViewControllers{ //图片大小建议32*32 [self addChildrenViewController:[[ViewController alloc] init] andTitle:@"首页" andImageName:@"tab1_n" andSelectImage:@"tab1_p"]; [self addChildrenViewController:[[ViewController alloc] init] andTitle:@"扩展" andImageName:@"tab2_n" andSelectImage:@"tab2_p"]; //中间这个不设置东西，只占位 [self addChildrenViewController:[[ViewController alloc] init] andTitle:@"旋转" andImageName:@"" andSelectImage:@""]; [self addChildrenViewController:[[ViewController alloc] init] andTitle:@"发现" andImageName:@"tab3_n" andSelectImage:@"tab3_p"]; [self addChildrenViewController:[[ViewController alloc] init] andTitle:@"我" andImageName:@"tab4_n" andSelectImage:@"tab4_p"];}- (void)addChildrenViewController:(UIViewController *)childVC andTitle:(NSString *)title andImageName:(NSString *)imageName andSelectImage:(NSString *)selectedImage{ childVC.tabBarItem.image = [UIImage imageNamed:imageName]; childVC.tabBarItem.selectedImage = [UIImage imageNamed:selectedImage]; childVC.title = title;  BaseNavigationController *baseNav = [[BaseNavigationController alloc] initWithRootViewController:childVC];  [self addChildViewController:baseNav];}

#import@interface MCTabBar : UITabBar@property (nonatomic, strong) UIButton *centerBtn; //中间按钮@end``````@implementation MCTabBar- (instancetype)init{ if (self = [super init]){ [self initView]; } return self;}- (void)initView{ _centerBtn = [UIButton buttonWithType:UIButtonTypeCustom]; // 设定button大小为适应图片 UIImage *normalImage = [UIImage imageNamed:@"tabbar_add"]; _centerBtn.frame = CGRectMake(0, 0, normalImage.size.width, normalImage.size.height); [_centerBtn setImage:normalImage forState:UIControlStateNormal]; //去除选择时高亮 _centerBtn.adjustsImageWhenHighlighted = NO; //根据图片调整button的位置(图片中心在tabbar的中间最上部，这个时候由于按钮是有一部分超出tabbar的，所以点击无效，要进行处理) _centerBtn.frame = CGRectMake(([UIScreen mainScreen].bounds.size.width - normalImage.size.width)/2.0, - normalImage.size.height/2.0, normalImage.size.width, normalImage.size.height); [self addSubview:_centerBtn];}//处理超出区域点击无效的问题- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event{ UIView *view = [super hitTest:point withEvent:event]; if (view == nil){ //转换坐标 CGPoint tempPoint = [self.centerBtn convertPoint:point fromView:self]; //判断点击的点是否在按钮区域内 if (CGRectContainsPoint(self.centerBtn.bounds, tempPoint)){  //返回按钮  return _centerBtn; } } return view;}```

//MCTabBarController.m- (void)viewDidLoad { [super viewDidLoad];  _mcTabbar = [[MCTabBar alloc] init]; [_mcTabbar.centerBtn addTarget:self action:@selector(buttonAction:) forControlEvents:UIControlEventTouchUpInside]; //选中时的颜色 _mcTabbar.tintColor = [UIColor colorWithRed:27.0/255.0 green:118.0/255.0 blue:208/255.0 alpha:1]; //透明设置为NO，显示白色，view的高度到tabbar顶部截止，YES的话到底部 _mcTabbar.translucent = NO; //利用KVC 将自己的tabbar赋给系统tabBar [self setValue:_mcTabbar forKeyPath:@"tabBar"];  self.delegate = self; [self addChildViewControllers];}```

- (void)buttonAction:(UIButton *)button{ self.selectedIndex = 2;//关联中间按钮 [self rotationAnimation];}//tabbar选择时的代理- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController{ if (tabBarController.selectedIndex == 2){//选中中间的按钮 [self rotationAnimation]; }else { [_mcTabbar.centerBtn.layer removeAllAnimations]; }}//旋转动画- (void)rotationAnimation{ CABasicAnimation *rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"]; rotationAnimation.toValue = [NSNumber numberWithFloat:M_PI*2.0]; rotationAnimation.duration = 3.0; rotationAnimation.repeatCount = HUGE; [_mcTabbar.centerBtn.layer addAnimation:rotationAnimation forKey:@"key"];}