集中中央标签栏按钮

Question

这是如何完成的？中央标签栏按钮的圆顶效果？它是圆顶图像在规则中央形状的标签按钮顶部的简单投影吗？或者还有什么更多呢？

Answer 1

你可以做到这一点，

UIButton* button = [UIButton buttonWithType:UIButtonTypeCustom]; 
    button.frame = CGRectMake(0.0, 0.0, buttonImage.size.width, buttonImage.size.height); 
    [button setBackgroundImage:buttonImage forState:UIControlStateNormal]; 
    [button setBackgroundImage:highlightImage forState:UIControlStateHighlighted]; 

    CGFloat heightDifference = buttonImage.size.height - self.tabBar.frame.size.height; 
    if (heightDifference < 0) 
     button.center = self.tabBar.center; 
    else 
    { 
     CGPoint center = self.tabBar.center; 
     center.y = center.y - heightDifference/2.0; 
     button.center = center; 
    } 

    [self.view addSubview:button]; 

请查看以下链接： http://idevrecipes.com/2010/12/16/raised-center-tab-bar-button/

您将在https://github.com/boctor/idev-recipes/tree/master/RaisedCenterTabBar