SizeToFit on UIScrollView的内容大小

Question

UIView有一个SizeToFit方法，它将使UIView适合所有的子视图。有没有类似的东西，它只会返回它计算的大小，而不会修改任何视图的框架。

我在UIScrollView上有几个子视图，我想在scroll view的contentSize上做SizeToFit，而不是它的框架。我必须在contentSize上做，因为我不想增加UIScrollView的“实际”大小，并且内容是动态加载和异步加载的，所以当我将子视图添加到UIScrollView时我不能手动加载。

Answer 1

目前，这是最好的我：

CGRect contentRect = CGRectZero; 
for (UIView *view in self.subviews) 
    contentRect = CGRectUnion(contentRect, view.frame); 
self.contentSize = contentRect.size; 

Answer 2

将UIView放入具有相同宽度和高度的UIScrollView，并将所有子视图添加到IT而不是滚动视图。然后将scrollview上的clipToBounds属性设置为TRUE，并在您的UIView上调用sizeToFit。您还可以将UIView背景的不透明度设置为0，使其不可见，但仍显示其子视图。

Answer 3

如果你的函数被频繁调用，您不希望每次在子视图进行迭代。相反，无论何时添加子视图，都要对当前的contentSize和新子视图的框架进行联合。

- (void)didAddSubview:(UIView *)subview { 
    CGRect tmp; 
    tmp.origin = CGPointZero; 
    tmp.size = self.contentSize; 
    tmp = CGRectUnion(tmp,subview.frame); 
    self.contentSize = tmp.size; 
} 

Answer 4

找到了解决办法在这里ScrollView ContentSize，你就能找到子视图的大小和找到的总含量的大小，也选择说子视图是否水平或垂直排列。

这里是从上面的链接代码：

@interface UIScrollView(auto_size) 
- (void) adjustHeightForCurrentSubviews: (int) verticalPadding; 
- (void) adjustWidthForCurrentSubviews: (int) horizontalPadding; 
- (void) adjustWidth: (bool) changeWidth andHeight: (bool) changeHeight withHorizontalPadding: (int) horizontalPadding andVerticalPadding: (int) verticalPadding; 
@end 

@implementation UIScrollView(auto_size) 
- (void) adjustWidth: (bool) changeWidth andHeight: (bool) changeHeight withHorizontalPadding: (int) horizontalPadding andVerticalPadding: (int) verticalPadding { 
    float contentWidth = horizontalPadding; 
    float contentHeight = verticalPadding; 
    for (UIView* subview in self.subviews) { 
     [subview sizeToFit]; 
     contentWidth += subview.frame.size.width; 
     contentHeight += subview.frame.size.height; 
    } 

    contentWidth = changeWidth ? contentWidth : self.superview.frame.size.width; 
    contentHeight = changeHeight ? contentHeight : self.superview.frame.size.height; 

    NSLog(@"Adjusting ScrollView size to %fx%f, verticalPadding=%d, horizontalPadding=%d", contentWidth, contentHeight, verticalPadding, horizontalPadding); 
    self.contentSize = CGSizeMake(contentWidth, contentHeight); 
} 

- (void) adjustHeightForCurrentSubviews: (int) verticalPadding { 
    [self adjustWidth:NO andHeight:YES withHorizontalPadding:0 andVerticalPadding:verticalPadding]; 
} 

- (void) adjustWidthForCurrentSubviews: (int) horizontalPadding { 
    [self adjustWidth:YES andHeight:NO withHorizontalPadding:horizontalPadding andVerticalPadding:0]; 
} 
@end 

同时一定要看看博客页面上的评论作为提供替代解决方案。

-anoop

Answer 5

我已经作出一个功能设置滚动视图的内容大小尝试它，享受

首先写这个函数...

-(void)setContentSizeOfScrollView:(UIScrollView*)scroll 
{ 
    CGRect rect = CGRectZero; 

    for(UIView * vv in [scroll subviews]) 
    { 
     rect = CGRectUnion(rect, vv.frame); 
    } 

    [scroll setContentSize:CGSizeMake(rect.size.width, rect.size.height)]; 
} 

再加入所有元素之后只需调用该函数并将滚动视图作为参数传递即可.....

[self setContentSizeOfScrollView:self.YourScrollView]; 

我100％肯定它会工作.........

Answer 6

在SWIFT 2.1，添加到您的视图控制器：

override func viewDidLayoutSubviews() { 
    super.viewDidLayoutSubviews() 

    let aggregateView = contentView.subviews.reduce(CGRect()) 
     { aggRect, view in aggRect.union(view.frame) } 

    scrollView.contentSize = aggregateView.size 

} 

Answer 7

斯威夫特2扩展：

用法：

scrollView.contentResize
scrollView.contentWidthResize
scrollView.contentHeightResize

extension UIScrollView { 

    ///Will resize content size to fit all subviews. 
    func contentResize(){ 

     var w = CGFloat(0) 
     var h = CGFloat(0) 

     for view in self.subviews{ 

      let fw = view.frame.origin.x + view.frame.width 
      let fh = view.frame.origin.y + view.frame.height 

      w = max(fw, w) 
      h = max(fh, h) 

     } 

     contentSize = CGSize(width: w, height: h) 

    } 

    ///Will resize content width size to fit all subviews. 
    func contentWidthResize(){ 

     var w = CGFloat(0) 

     for view in self.subviews{ 

      let fw = view.frame.origin.x + view.frame.width 

      w = max(fw, w) 

     } 

     contentSize.width = w 

    } 

    ///Will resize content height size to fit all subviews. 
    func contentHeightResize(){ 

     var h = CGFloat(0) 

     for view in self.subviews{ 

      let fh = view.frame.origin.y + view.frame.height 

      h = max(fh, h) 

     } 

     contentSize.height = h 

    } 

} 

Answer 8

这是Swift 3的答案。0

override func viewDidLayoutSubviews() { 
    super.viewDidLayoutSubviews() 
    var contentRect: CGRect = CGRect.zero 
    for view in self.scrollView.subviews { 
     debugPrint("view frame \(view.frame)") 
     contentRect = contentRect.union(view.frame) 
     debugPrint("frame \(contentRect)") 
    } 
    self.scrollView.contentSize = contentRect.size 
    debugPrint("content size \(self.scrollView.contentSize)") 
} 

Answer 9

虽然William's answer是非常有用的，它并不完美，因为滚动条也滚动视图的子视图的工作。原来，诀窍是在计算内容大小之前将其隐藏起来。这里的斯威夫特3码会是什么样子：

override func viewDidLayoutSubviews() { 
    scrollView.layoutSubviews() 

    // disable scrollbars so they don't interfere during resizing 
    scrollView.showsVerticalScrollIndicator = false 
    scrollView.showsHorizontalScrollIndicator = false 

    scrollView.contentSize = scrollView.subViewArea() 

    // re-enable the scrollbars 
    scrollView.showsVerticalScrollIndicator = true 
    scrollView.showsHorizontalScrollIndicator = true 
} 

您还需要在某处添加以下扩展名在您的项目：

extension UIScrollView { 
    func subViewArea() -> CGSize { 
     var rect = CGRect.zero 
     for subview in subviews { 
      rect = rect.union(subview.frame) 
     } 

     return rect.size 
    } 
} 

Answer 10

它不够的，工会帧大小来计算内容尺寸。因为有时候，你的子视图需要重叠，有时你在子视图之间有空白。你必须知道和计算子视图的来源。

联盟的做法给出了A和B的设计相同的内容HIGHT。但如果你知道去年最大的子视图，就可以计算出正确的内容高度：

该扩展程序可以计算真正的内容高度。

extension UIScrollView { 

func adjustContentHeight(bottomPadding: Int = 0) { 

    var lastSub: CGRect = .zero 
    self.subviews.forEach({ 
     let sub = $0.frame 
     if(sub.maxY > lastSub.maxY) { 
      lastSub = sub 
     } 
    }) 

    self.contentSize.height = lastSub.maxY + CGFloat(bottomPadding) 
} 
}