UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"版本更新" message:descript preferredStyle:UIAlertControllerStyleAlert];
UIView *subView1 = alert.view.subviews[0];
UIView *subView2 = subView1.subviews[0];
UIView *subView3 = subView2.subviews[0];
UIView *subView4 = subView3.subviews[0];
UIView *subView5 = subView4.subviews[0];
//取title和message：
//UILabel *title = subView5.subviews[0];
UILabel *message = subView5.subviews[1];
//然后设置message内容居左：
message.textAlignment = NSTextAlignmentLeft;
[message setValue:[UIColor redColor] forKey:@"textColor"];
