自动布局让我的生活很困难。从理论上讲,当我转换的时候,它会非常有用,但我似乎一直在与它作斗争。
我做了一个演示项目来寻求帮助。有人知道如何使视图之间的空间增加或减少均匀,每当视图调整大小?
下面是三个标签(手动垂直对齐):
我想要的是,当我旋转时,它们均匀地调整间距(而不是视图大小)。默认情况下,顶部和底部视图向中心挤压:
自动布局让我的生活很困难。从理论上讲,当我转换的时候,它会非常有用,但我似乎一直在与它作斗争。
我做了一个演示项目来寻求帮助。有人知道如何使视图之间的空间增加或减少均匀,每当视图调整大小?
下面是三个标签(手动垂直对齐):
我想要的是,当我旋转时,它们均匀地调整间距(而不是视图大小)。默认情况下,顶部和底部视图向中心挤压:
当前回答
是的,你可以只在接口构建器中这样做,而不需要编写代码——需要注意的是,你是在调整标签的大小,而不是分配空白。在本例中,将标签2的X和Y对齐到父视图,使其固定在中心。然后将标签1的垂直空间设置为superview,标签2设置为standard,重复标签3。在设置标签2之后,设置标签1和3最简单的方法是调整它们的大小,直到它们断开。
这是水平显示,注意标签1和2之间的垂直空间被设置为标准:
这是竖屏版本:
我意识到,由于标签之间的标准空间和父视图的标准空间之间的差异,它们在基线之间不是绝对100%等间距的。如果这让您感到困扰,可以将大小设置为0而不是standard
其他回答
查看开源库PureLayout。它提供了一些用于分布视图的API方法,包括每个视图之间的间距是固定的(视图大小根据需要而变化),以及每个视图的大小是固定的(视图之间的间距根据需要而变化)。请注意,所有这些都是在没有使用任何“间隔视图”的情况下完成的。
从NSArray + PureLayout.h:
// NSArray+PureLayout.h
// ...
/** Distributes the views in this array equally along the selected axis in their superview. Views will be the same size (variable) in the dimension along the axis and will have spacing (fixed) between them. */
- (NSArray *)autoDistributeViewsAlongAxis:(ALAxis)axis
alignedTo:(ALAttribute)alignment
withFixedSpacing:(CGFloat)spacing;
/** Distributes the views in this array equally along the selected axis in their superview. Views will be the same size (fixed) in the dimension along the axis and will have spacing (variable) between them. */
- (NSArray *)autoDistributeViewsAlongAxis:(ALAxis)axis
alignedTo:(ALAttribute)alignment
withFixedSize:(CGFloat)size;
// ...
由于它都是开源的,如果您有兴趣了解如何在没有间隔视图的情况下实现这一点,只需查看实现即可。(这取决于同时利用约束的常数和乘数。)
我找到了一个完美而简单的方法。自动布局不允许你平等地调整空间大小,但它允许你平等地调整视图大小。简单地在你的字段之间放置一些不可见的视图,并告诉自动布局保持它们相同的大小。它工作得很完美!
但有一件事值得注意;当我在界面设计器中减小尺寸时,有时它会混淆,在原来的地方留下一个标签,如果大小改变了奇数个量,它就会发生冲突。除此之外,它工作得很完美。
编辑:我发现冲突成了一个问题。因此,我删除了其中一个间距约束,并将其替换为两个约束,一个大于或等于,一个小于或等于。两者的大小相同,优先级比其他约束低得多。结果没有进一步的冲突。
Android has a method of chaining views together in its constraint based layout system that I wanted to mimic. Searches brought me here but none of the answers quite worked. I didn't want to use StackViews because they tend to cause me more grief down the line than they save up front. I ended up creating a solution that used UILayoutGuides placed between the views. Controlling their width's allows different types of distributions, chain styles in Android parlance. The function accepts a leading and trailing anchor instead of a parent view. This allows the chain to be placed between two arbitrary views rather than distributed inside of the parent view. It does use UILayoutGuide which is only available in iOS 9+ but that shouldn't be a problem anymore.
public enum LayoutConstraintChainStyle {
case spread //Evenly distribute between the anchors
case spreadInside //Pin the first & last views to the sides and then evenly distribute
case packed //The views have a set space but are centered between the anchors.
}
public extension NSLayoutConstraint {
static func chainHorizontally(views: [UIView],
leadingAnchor: NSLayoutXAxisAnchor,
trailingAnchor: NSLayoutXAxisAnchor,
spacing: CGFloat = 0.0,
style: LayoutConstraintChainStyle = .spread) -> [NSLayoutConstraint] {
var constraints = [NSLayoutConstraint]()
guard views.count > 1 else { return constraints }
guard let first = views.first, let last = views.last, let superview = first.superview else { return constraints }
//Setup the chain of views
var distributionGuides = [UILayoutGuide]()
var previous = first
let firstGuide = UILayoutGuide()
superview.addLayoutGuide(firstGuide)
distributionGuides.append(firstGuide)
firstGuide.identifier = "ChainDistribution\(distributionGuides.count)"
constraints.append(firstGuide.leadingAnchor.constraint(equalTo: leadingAnchor))
constraints.append(first.leadingAnchor.constraint(equalTo: firstGuide.trailingAnchor, constant: spacing))
views.dropFirst().forEach { view in
let g = UILayoutGuide()
superview.addLayoutGuide(g)
distributionGuides.append(g)
g.identifier = "ChainDistribution\(distributionGuides.count)"
constraints.append(contentsOf: [
g.leadingAnchor.constraint(equalTo: previous.trailingAnchor),
view.leadingAnchor.constraint(equalTo: g.trailingAnchor)
])
previous = view
}
let lastGuide = UILayoutGuide()
superview.addLayoutGuide(lastGuide)
constraints.append(contentsOf: [lastGuide.leadingAnchor.constraint(equalTo: last.trailingAnchor),
lastGuide.trailingAnchor.constraint(equalTo: trailingAnchor)])
distributionGuides.append(lastGuide)
//Space the according to the style.
switch style {
case .packed:
if let first = distributionGuides.first, let last = distributionGuides.last {
constraints.append(first.widthAnchor.constraint(greaterThanOrEqualToConstant: spacing))
constraints.append(last.widthAnchor.constraint(greaterThanOrEqualToConstant: spacing))
constraints.append(last.widthAnchor.constraint(equalTo: first.widthAnchor))
constraints.append(contentsOf:
distributionGuides.dropFirst().dropLast()
.map { $0.widthAnchor.constraint(equalToConstant: spacing) }
)
}
case .spread:
if let first = distributionGuides.first {
constraints.append(contentsOf:
distributionGuides.dropFirst().map { $0.widthAnchor.constraint(equalTo: first.widthAnchor) })
}
case .spreadInside:
if let first = distributionGuides.first, let last = distributionGuides.last {
constraints.append(first.widthAnchor.constraint(equalToConstant: spacing))
constraints.append(last.widthAnchor.constraint(equalToConstant: spacing))
let innerGuides = distributionGuides.dropFirst().dropLast()
if let key = innerGuides.first {
constraints.append(contentsOf:
innerGuides.dropFirst().map { $0.widthAnchor.constraint(equalTo: key.widthAnchor) }
)
}
}
}
return constraints
}
基于Ben Dolman的回答,这将更均匀地分配视图(使用填充等):
+(NSArray *)constraintsForEvenDistributionOfItems:(NSArray *)views
relativeToCenterOfItem:(id)toView vertically:(BOOL)vertically
{
NSMutableArray *constraints = [NSMutableArray new];
NSLayoutAttribute attr = vertically ? NSLayoutAttributeCenterY : NSLayoutAttributeCenterX;
CGFloat min = 0.25;
CGFloat max = 1.75;
CGFloat d = (max-min) / ([views count] - 1);
for (NSUInteger i = 0; i < [views count]; i++) {
id view = views[i];
CGFloat multiplier = i * d + min;
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:view
attribute:attr
relatedBy:NSLayoutRelationEqual
toItem:toView
attribute:attr
multiplier:multiplier
constant:0];
[constraints addObject:constraint];
}
return constraints;
}
你可以创建一个tableView并使isScrollEnabled = false。