iOS - 滚动大于屏幕的绘图

Question

我正在尝试做日历的日视图。在android上我创建了一个画布（比屏幕大）并将其放在一个scrollview上。一切都很棒。抽签结束后，我可以滚动画布。

但是在iOS上，当我在UIScrollView上绘图时，我无法在屏幕上进行任何滚动手势。任何人都可以帮助我吗？

 for (int i = 1; i <18; i++){

    UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(40, i*80, 240, 1)];
    lineView.backgroundColor = [UIColor blackColor];
    [self.scrollView addSubview:lineView];

    int n = i+7;
    NSString *str = nil;
    if(n<10){
        str = [NSString stringWithFormat:@"0%d:00", n];
    }
    else{str = [NSString stringWithFormat:@"%d:00", n];}

    UIFont *font = [UIFont systemFontOfSize:13.0f];
    NSMutableAttributedString *s2 = [[NSMutableAttributedString alloc] initWithData:[str dataUsingEncoding:NSUTF8StringEncoding] options:@{NSDocumentTypeDocumentAttribute:NSPlainTextDocumentType} documentAttributes:nil error:nil];
    [s2 addAttributes:@{NSFontAttributeName: font} range:NSMakeRange(0, s2.length)];

    UILabel *hour = [[UILabel alloc] initWithFrame:CGRectMake(0, i*80-4, 240, 10)];
    hour.attributedText = s2;
    [self.scrollView addSubview:hour];