改变UISegmentedControl样式，改变字体

NSDictionary *textDic = [NSDictionary dictionaryWithObjectsAndKeys:
                             [[UIColor blackColor]       colorWithAlphaComponent:0.6f],UITextAttributeTextColor,
                             [UIColor grayColor],UITextAttributeTextShadowColor,
                             [NSValue valueWithUIOffset:UIOffsetMake(1, 0)],UITextAttributeTextShadowOffset,
                             [UIFont systemFontOfSize:13],UITextAttributeFont,nil];
    
    [mySegment setTitleTextAttributes:textDic forState:UIControlStateNormal];