自定制alert提示框
推荐更全面，可自定义程度更高的提示框框架：https://github.com/lixiang1994/LEEAlert
##设置提示框默认的样式## XDAlertConfiguration *config = [[XDAlertConfiguration alloc] init]; config.buttonBackgroundColor = [UIColor orangeColor]; config.buttonTextColor = [UIColor whiteColor]; config.cornerRadius = 10.0; config.titleFont = 20.0; config.messageFont = 17.0; config.messageColor = [UIColor orangeColor]; config.buttonCornerRadius = 5.0; config.viewBackgroundColor = [UIColor whiteColor];
[XDAlertViewController setDefaultConfiguration:config];
##alert样式
##sheet样式
