//背景渐变
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = CGRectMake(0, 0, headerView.frame.size.width, headerView.frame.size.height);
gradient.colors = [NSArray arrayWithObjects:
(id)Color_4690fa.CGColor,
(id)Color_0069fe.CGColor,
nil];
[headerView.layer insertSublayer:gradient atIndex:0];
