StackUI 0.0.16

StackUI 0.0.16

Maintained by pujiaxin.



StackUI 0.0.16

  • By
  • pujiaxin33

StackUI

中文文档

Use UIStackView like SwiftUI.

Use @propertyWrapper, @resultBuilder, chain syntax and other features used by SwiftUI, making UIStackView easy to use. For classes such as Label, Button, and ImageView, it is still the way to use UIKit, but it is encapsulated with chain syntax.

Because SwiftUI requires an iOS13+ system to be used, it is almost impossible to use SwiftUI in actual projects. But the features of SwiftUI are really fascinating, so StackUI is the implementation of SwiftUI in the scope of UIStackView. You can experience some of the features of SwiftUI in StackUI, so that you can learn the new features earlier.

If you are tired of configuring the constraints of UIKit, then StackUI will be a good helper for you. The declarative layout make world better.

Features

  • Declarative syntax similar to SwiftUI;
  • Data-driven UI, update data then UI automatically updates;
  • Support HScrollStack, VScrollStack, when the content exceeds the width or height of the stack, scrolling is automatically turned on;
  • Chained syntax configuration UIKit;
  • Can flexibly extend custom classes to support StackUI;

Require

  • iOS 9.0+
  • XCode 13.0+
  • Swift 5.4+

Install

CocoaPods

target'<Your Target Name>' do
    pod'StackUI'
    //If you want to use RxSwift
    pod'StackUI/RxSwift'
end

Execute pod repo update first, then execute pod install

SPM

Example

HStack

    HStack(alignment: .center, spacing: 5) {
        ImageView().image(UIImage(named: "avatar")).size(width: 40, height: 40)
        Label("user nickname").font(.systemFont(ofSize: 18, weight: .medium))
    }

VStack

    VStack {
        Label("user nickname").font(.systemFont(ofSize: 18, weight: .medium))
        Label().text("The user is lazy, nothing left!").font(.systemFont(ofSize: 12)).textColor(.gray)
    }

HScrollStack and ForIn

    var users = [UserModel]()
    for index in 0...25 {
        let model = UserModel(avatar: "avatar", name: "user\(index)", desc: "user description\(index)")
        users.append(model)
    }
    HScrollStack() {
        for model in users {
            HStack(alignment: .center, spacing: 5) {
                Spacer(spacing: 12)
                ImageView().image(UIImage(named: model.avatar)).size(width: 80, height: 80)
                VStack {
                    Label(model.name).font(.systemFont(ofSize: 18, weight: .medium))
                    Label().text(model.desc).font(.systemFont(ofSize: 12)).textColor(.gray)
                }
                Divider()
            }.size(width: 300)
        }
    }

@Live

Add @Live in front of the property, and add the $ symbol prefix when using it. When updating properties, the associated UIKit will automatically update the interface.

    //definition
    @Live var nickName: String? = "User nickname"
    @Live var desc: String? = "The user is lazy, and nothing is left!"
    
    //use
    HStack(distribution: .equalCentering, alignment: .center) {
        HStack(alignment: .center, spacing: 5) {
            ImageView().image(UIImage(named: "avatar")).size(width: 40, height: 40)
            VStack {
                Label($nickName).font(.systemFont(ofSize: 18, weight: .medium))
                Label().text($desc).font(.systemFont(ofSize: 12)).textColor(.gray)
            }
        }
        ImageView().image(UIImage(named: "arrow_right"))
    }
    
    //update
    nickName = "Jay Chou"
    desc = "Ouch, not bad ❤️"

Driver of RxSwift

    //definition
    var nickName = PublishSubject<String?>()
    var desc = PublishSubject<String?>()
    
    //use
    HStack(distribution: .equalCentering, alignment: .center) {
        HStack(alignment: .center, spacing: 5) {
            ImageView().image(UIImage(named: "avatar")).size(width: 40, height: 40)
            VStack {
                Label(nickName.asDriver(onErrorJustReturn: nil)).font(.systemFont(ofSize: 18, weight: .medium))
                Label().text(desc.asDriver(onErrorJustReturn: nil)).font(.systemFont(ofSize: 12)).textColor(.gray)
            }
        }
        ImageView().image(UIImage(named: "arrow_right"))
    }
    
    //update
    nickName.onNext("Jay Chou")
    desc.onNext("Ouch, not bad ❤️")

Custom View supports StackUI

You can customize the parent class

Inherit from View, Label, etc., and then extend custom attributes.

class CustomView: View {
    var customColor: UIColor = .black
    
    func customColor(_ customColor: UIColor) -> Self {
        self.customColor = customColor
        self.backgroundColor = customColor
        return self
    }
}
class CustomLabel: Label {
    var customColor: UIColor = .black
    
    func customColor(_ customColor: UIColor) -> Self {
        self.customColor = customColor
        self.textColor = customColor
        return self
    }
}

If Statement

     var isShowInfo: Bool = false
     HStack(distribution: .equalCentering, alignment: .center) {
         HStack(alignment: .center, spacing: 5) {
             ImageView().image(UIImage(named: "avatar")).size(width: 40, height: 40)
             if self.isShowInfo == true {
                 VStack {
                     Label("User nickname").font(.systemFont(ofSize: 18, weight: .medium))
                     Label().text("The user is lazy, nothing left!").font(.systemFont(ofSize: 12)).textColor(.gray)
                 }
             }else {
                 Label("No Information")
             }
         }
         ImageView().image(UIImage(named: "arrow_right"))
     }

The parent class cannot be modified, conform the protocol

Conform protocols such as StackUIView and StackUILabel, and then extend custom attributes.

class CustomViewFromProtocol: UIView, StackUIView {
    var customColor: UIColor = .black
    
    func customColor(_ customColor: UIColor) -> Self {
        self.customColor = customColor
        self.backgroundColor = customColor
        return self
    }
}
class CustomLabelFromProtocol: UILabel, StackUILabel {
    var customColor: UIColor = .black
    
    func customColor(_ customColor: UIColor) -> Self {
        self.customColor = customColor
        self.textColor = customColor
        return self
    }
}

Attribute configuration not supported by chain syntax yet

Unified configuration through apply closure

HStack(alignment: .center, spacing: 5) {
     Label().text(model.desc).apply {label in
         //If there are attributes that are not defined by the chain syntax, they can be configured in the apply closure, or they can be submitted to Issue for support.
         label.font = UIFont.systemFont(ofSize: 10)
         label.textColor = .gray
     }
}

ViewBox use

Sometimes the view needs margins. At this time, you can put the view into the ViewBox, and then set the paddings, so you can indirectly set the top, bottom, left, and right margins of the view. As shown in the following code: Label has margins of top: 10, left: 20, bottom: 10, right: 20.

ViewBox(paddings: .init(top: 10, left: 20, bottom: 10, right: 20)) {
     Label("Hobbies: writing code;").font(. systemFont(ofSize: 15)).numberOfLines(0)
}.backgroundColor(.lightGray)

Currently supported classes

  • Layer:The relevant properties of Layer are configured in the View class
  • View
  • ImageView
  • Control
  • Label
  • Button
  • TextField
  • TextView
  • Stepper
  • SwitchUI
  • PageControl
  • Slider
  • Spacer
  • Divider
  • ActivityIndicatorView
  • ScrollView
  • TableView
  • CollectionView

If there are other classes and attributes that need to be supported, please submit an Issue or Pull Request.