即使我设置了内容大小,UIScrollView也不会滚动

Question

我有一个UIView是UIScrollView的子视图.

我这样做是为了设置内容大小viewDidLoad(我在这个网站上找到的有用片段):

CGFloat scrollViewHeight = 0.0f;
for (UIView* view in self.scrollView.subviews)
{
    scrollViewHeight += view.frame.size.height;
}

[self.scrollView setContentSize:(CGSizeMake(320, scrollViewHeight))];

使用NSLog我确定内容大小高度大于滚动视图的高度.但是,它仍然不会滚动.(我只对垂直滚动感兴趣.)

在IB中启用了滚动,所以我错过了什么？

Answer 1

这也发生在我身上 - 似乎从nib文件加载视图时,一些调整大小发生在 viewDidLoad 之后,甚至在viewWillAppear之后.调用堆栈显示正在执行此操作的是resizeWithOldSuperviewSize

#0  0x0000f040 in -[ScrollView setContentSize:] at .../ScrollView.m:49
#1  0x00092863 in -[UIScrollView _resizeWithOldSuperviewSize:] ()
#2  0x0007357a in -[UIView(Geometry) resizeWithOldSuperviewSize:] ()
#3  0x00072178 in __46-[UIView(Geometry) resizeSubviewsWithOldSize:]_block_invoke_0 ()
#4  0x01ccb5a7 in __NSArrayChunkIterate ()
#5  0x01ca303f in __NSArrayEnumerate ()
#6  0x01ca2a16 in -[NSArray enumerateObjectsWithOptions:usingBlock:] ()
#7  0x0007210f in -[UIView(Geometry) resizeSubviewsWithOldSize:] ()
#8  0x0056d14c in -[UIView(AdditionalLayoutSupport) _is_layout] ()
#9  0x00076dfe in -[UIView(Hierarchy) layoutSubviews] ()
#10 0x0007e92d in -[UIView(CALayerDelegate) layoutSublayersOfLayer:] ()
#11 0x010fa6b0 in -[NSObject performSelector:withObject:] ()
#12 0x022a5fc0 in -[CALayer layoutSublayers] ()
#13 0x0229a33c in CA::Layer::layout_if_needed(CA::Transaction*) ()
#14 0x022a5eaf in -[CALayer layoutIfNeeded] ()
#15 0x0011d8cd in -[UIViewController window:setupWithInterfaceOrientation:] ()
#16 0x000661a6 in -[UIWindow _setRotatableClient:toOrientation:updateStatusBar:duration:force:isRotating:] ()
#17 0x00064cbf in -[UIWindow _setRotatableClient:toOrientation:updateStatusBar:duration:force:] ()
#18 0x00064bd9 in -[UIWindow _setRotatableViewOrientation:duration:force:] ()
#19 0x00063e34 in __57-[UIWindow _updateToInterfaceOrientation:duration:force:]_block_invoke_0 ()
#20 0x00063c6e in -[UIWindow _updateToInterfaceOrientation:duration:force:] ()
#21 0x00064a29 in -[UIWindow setAutorotates:forceUpdateInterfaceOrientation:] ()
#22 0x00067922 in -[UIWindow setDelegate:] ()
#23 0x00111fec in -[UIViewController _tryBecomeRootViewControllerInWindow:] ()
#24 0x0005ebc4 in -[UIWindow addRootViewControllerViewIfPossible] ()
#25 0x0005edbf in -[UIWindow _setHidden:forced:] ()
#26 0x0005ef55 in -[UIWindow _orderFrontWithoutMakingKey] ()
#27 0x00067f67 in -[UIWindow makeKeyAndVisible] ()
#28 0x0000379a in -[AppDelegate application:didFinishLaunchingWithOptions:] at .../AppDelegate.m:24

除了稍后通过​​调用performSelector:withObject:afterDelay设置contentSize之外,我没有找到合适的解决方案

-(void)viewDidLoad
{
    [self performSelector:@selector(adjustScrollViewContentSize) withObject:nil afterDelay:0.1];
}

-(void)adjustScrollViewContentSize
{
    _scrollView.contentSize = CGSizeMake(4000, 4000);
}

Answer 2

userInteractionEnabled属性是否等于TRUE？也许你的滚动视图的子视图正在窃取触摸？