PinStackView was a Frame base StackView relies on PinLayout.

• can be used with manual layout, Autolayout
• is a real view and only layout specified sub-views
• has inner padding
• has equal distribution like UIStackView
• has auto style with dynamic length in axis direction
• has grow/shrink
• observ item layout properties
• KVO item views 'isHidden'

To integrate PinStackView into your Xcode project using CocoaPods, specify it in your Podfile:

    pod 'PinStackView'

Then, run pod install.

examples listed in project 'Views/' group

$ cd Example
$ pod install
$ open Example.xcworkspace

• addItems(): add managed sub-views, return PinStackItemInfo for chained setting, you can addSubviews() and layout view by yourself
• insertItem(): like addItems(), can defined sequence
• removeItem(): remove managed sub-views, also removed from subviews
• remakeItem(): replace with new item but did not change subview's sequence
• itemForView(): get PinStackItemInfo from PinStackView after addItem() or insertItem()
• define(): a sugar to chain items info definition
• markDirty(): like setNeesLayout(), force layout in next view update
• triggerNeedsLayout(): trigger subview's setNeedsLayout when PinStackView setNeedsLayout.

• style: default .fixed, the axis length will not change after layout; .auto style means its axis length will change by items
• axis: .horizontal or .vertical direction, dynamic length direction
• distribution: axis direction layout style, .equal only support .fixed style; .auto style always .start
• alignment: cross axis direction, you can specify view's alignment by alignSelf()
• spacing: spacing between items in axis direction
• padding: items will layout after padding
• layoutCallback: call back after every layout, will pass in true when size changed

PinStackItemInfo was each item's layout definition, you will get instance after addItem()

• top(): top margin, points or inner height ratio after padding
• bottom(): bottom margin, points or inner height ratio after padding
• left(): left margin, points or inner width ratio after padding
• right(): right margin, points or inner width ratio after padding
• width(): points or inner width ratio after padding
• height(): points or inner height ratio after padding
• maxWidth(): max points or inner width ratio after padding, high priority than width()
• maxHeight(): max points or inner height ratio after padding, high priority than height()
• minWidth(): min points or inner width ratio after padding, high priority than width()
• minHeight(): min points or inner height ratio after padding, high priority than height()
• size(): highest priority than width(), height(), max/min width & height, points or ratio after padding
• alignSelf(): high priroty than PinStackView's alignment, only for this item
• grow(): in .fixed style and .start / .end distribution, it means item using dynamic length in axis direction after all fixed items length acumulated; no meanings in .equal distribution or .auto style
• shrink(): in .fixed style and.start / .end distribution, it means item using dynamic length in axis direction after all fixed items length acumulated; no meanings in .equal distribution or .auto style

using Then from Suyeol Jeon

    lazy var stackView = PinStackView().then {
        $0.style = .auto
        $0.axis = .horizontal
        $0.alignment = .center
        $0.distribution = .start
        $0.spacing = 10
        $0.addItem(v1).left(20)
        $0.addItem(v2).size(20).shrik(2.0)
        $0.addItem(v3).grow(1.0) // with grow ratio 1.0 / (1.0 + 2.0)
        $0.addItem(v4).size(30).grow(2.0).right(20)
    }