[iOS]自定义view使用xib

+ (instancetype)loadView {
    UINib *nib = [UINib nibWithNibName:@"ZZTicketProfitsReportHeadView" bundle:nil];
    ZZTicketProfitsReportHeadView *v = [nib instantiateWithOwner:nil options:nil].firstObject;
    return v;
}