我有一个UICollectionView
和UISegmentedControl
的视图。
我想更改约束,以便段控制器不会重叠集合视图,如下图所示:
这是我的代码:
override func viewDidLoad()
{
super.viewDidLoad()
self.navigationItem.leftBarButtonItem = nil
self.tabBarController?.tabBar.isHidden = true
self.SegmentController.setTitle(SegmentAtext, forSegmentAt: 0)
self.SegmentController.setTitle(SegmentBtext, forSegmentAt: 1)
self.view.bringSubview(toFront: SegmentController)
self.LoadProducts(productsToShow: SegmentAtype)
}
所以我添加这个命令:
self.ProductsCollection.topAnchor.constraint(equalTo: SegmentController.bottomAnchor, constant: 10).isActive = true
但结果更糟:
现在,分段控制器几乎完全隐藏了!
我该如何解决?
编辑:
我的viewDidLayoutSubviews函数:
override func viewDidLayoutSubviews()
{
ProductsCollection.translatesAutoresizingMaskIntoConstraints = false
let topConstraint = NSLayoutConstraint(item: ProductsCollection, attribute: .top, relatedBy: .equal, toItem: self.view, attribute: .top, multiplier: 1, constant: 20)
let bottomConstraint = NSLayoutConstraint(item: ProductsCollection, attribute: .bottom, relatedBy: .equal, toItem: self.view, attribute: .bottom, multiplier: 1, constant: -50) //leaving space for search field
let leadingConstraint = NSLayoutConstraint(item: ProductsCollection, attribute: .leading, relatedBy: .equal, toItem: self.view, attribute: .leading, multiplier: 1, constant: 0)
let trailingConstraint = NSLayoutConstraint(item: ProductsCollection, attribute: .trailing, relatedBy: .equal, toItem: self.view, attribute: .trailing, multiplier: 1, constant: 0)
self.view.addConstraints([topConstraint, bottomConstraint, leadingConstraint, trailingConstraint])
}
注意:
我的viewDidLayoutSubviews
是在超级视图中实现的,它不包含UISegmentedControl
。 UISegmentedControl
包含在继承视图中。
编辑:更新的视图
如果您希望UISegmentedControl
在屏幕上居中并在其下方拥有您的集合视图,那么您可以这样做
NSLayoutConstraint.activate([
segmentedControl.topAnchor.constraint(equalTo: view.topAnchor),
segmentedControl.centerXAnchor.constraint(equalTo: view.centerXAnchor),
collectionView.topAnchor.constraint(equalTo: segmentedControl.bottomAnchor),
collectionView.leftAnchor.constraint(equalTo: view.leftAnchor),
collectionView.rightAnchor.constraint(equalTo: view.rightAnchor),
collectionView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
])
所以我们将分段控件顶部放在视图的顶部,然后将其居中,然后集合视图的顶部是分段控件的底部(如果需要,可以为填充添加常量),并在视图的左下角放置