在iOS 6.0 Release notes中有以下声明:
请注意,您可以使滚动视图的子视图显示为浮动 (不滚动)通过创建约束来覆盖其他滚动内容 在视图和滚动视图的子树之外的视图之间,例如 滚动视图的超级视图。
有人有什么想法吗?
答案 0 :(得分:3)
我做了一些游戏,我有一个很好的例子。
视图不会滚动,它会放在顶部,其高度是scrollview hight和任意值之间的差异。
// in viewDidLoad
UIIView *myView = [[UIView alloc] init];
[self.scrollView addSubview:myView];
myView.translatesAutoresizingMaskIntoConstraints = NO;
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:self.mapView
attribute:NSLayoutAttributeTop
relatedBy:(NSLayoutRelationEqual)
toItem:self.containerView
attribute:(NSLayoutAttributeTop)
multiplier:1.0
constant:0];
[self.view addConstraint:constraint];
// Give my view some intrinsic size
NSDictionary *dict = NSDictionaryOfVariableBindings(myView);
NSArray *constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"|[myView]|"
options:(NSLayoutFormatAlignAllBaseline)
metrics:nil
views:dict];
[self.view addConstraints:constraints];
// In view did appear
// calc height from height of scroll view - this is needs work
float height = -self.scrollView.frame.size.height + 250;
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:self.mapView attribute:NSLayoutAttributeHeight
relatedBy:(NSLayoutRelationEqual)
toItem:self.containerView
attribute:(NSLayoutAttributeHeight)
multiplier:1.0
constant:offset];
[self.view addConstraint:constraint];