iOS:如何将内容从 ScrollView 复制到另一个 ScrollView

Question

• 我以编程方式创建了 UIScrollView 并向其中添加了多个 button。
• 它运行良好，没有任何问题。
• 但我需要通过复制先前 ScrollView 的内容来创建另一个 ScrollView 。

查询: 如何将First_Scrollview内容复制到Second_Scrollview

代码:

- (void)ScrollviewItems
{
    int x = 5;
    int y = 5;
    for(int i=0; i<totalButtonsCount; i++)
    {
        CategoryItem = [[UIButton alloc]initWithFrame:CGRectMake(x, y, buttonWidth, 50)];
        CategoryItem.titleLabel.backgroundColor = [UIColor clearColor];
        CategoryItem.backgroundColor = [UIColor redColor];
        [CategoryItem setTitle:[NSString stringWithFormat:@"%d",i]
                      forState:UIControlStateNormal];
        CategoryItem.tag = i;
        [CategoryItem addTarget:self
                         action:@selector(CategoryItemAction:)
         forControlEvents:UIControlEventTouchUpInside];
        [First_Scrollview addSubview:CategoryItem];
        x = x + (buttonWidth + 5);
    }
    First_Scrollview.contentSize = CGSizeMake(x,50);

    Second_Scrollview = [self.Category_Scrollview copy]; // Error
}

错误:

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIScrollView copyWithZone:]: unrecognized selector sent to instance 

Answer 1

你也可以通过这个for循环来做到这一点

for(UIView *v in self.scrollview1.subviews){
        [self.scrollview2 addSubview:v];
}