tabbar的优雅设计

- (void)layoutSubviews {

[super layoutSubviews];

self.label.mm_center();

CGPoint center = self.label.center;

center.x = self.bounds.size.width/2.0;

center.y = self.bounds.size.height/2.0;

self.label.center = center;

self.layer.cornerRadius = 0.5 * self.bounds.size.height;

}

- (CGSize)sizeThatFits:(CGSize)size {

[self.label sizeToFit];

CGFloat width = self.label.bounds.size.width + 8;

CGFloat height = self.label.bounds.size.height + 2;

if (width < height) {

width = height;

}

return CGSizeMake( width, height);

}