给UIButton设置阴影及动画组
//设置“开启旅程”按钮 UIButton *startBtn = self.startBtn; CGFloat btnW = 100; CGFloat btnH = 35; CGFloat btnX = (self.dataArray.count) * CGRectGetWidth(self.frame) + self.coreView.bounds.size.width/2-btnW/2; CGFloat btnY = self.coreView.bounds.size.height * 0.9; startBtn.frame = CGRectMake(btnX, btnY, btnW, btnH); [startBtn setTitle:@"开启旅程" forState:UIControlStateNormal]; [startBtn setTitleColor:[UIColor lightTextColor] forState:UIControlStateHighlighted]; [startBtn addTarget:self action:@selector(startBtnClicked) forControlEvents:UIControlEventTouchUpInside]; startBtn.titleLabel.font = [UIFont boldSystemFontOfSize:18]; startBtn.backgroundColor=[UIColor colorWithRed:44/255.0 green:178/255.0 blue:219/255.0 alpha:1]; startBtn.layer.cornerRadius = 8; startBtn.layer.shadowOffset = CGSizeMake(1, 1); startBtn.layer.shadowOpacity = 0.8; startBtn.layer.shadowColor = [UIColor blackColor].CGColor; [self.coreView addSubview:startBtn]; //"开启旅程"按钮动画 CAAnimationGroup *group = [CAAnimationGroup animation]; group.duration = 0.7; group.repeatCount = 1; CABasicAnimation *anima1 = [CABasicAnimation animation]; anima1.keyPath = @"opacity"; anima1.toValue = @0; CABasicAnimation *anima2 = [CABasicAnimation animation]; anima2.keyPath = @"transform.scale"; anima2.toValue = @2.5; group.animations = @[anima1, anima2]; [_startBtn.layer addAnimation:group forKey:nil];