ideal size

SwiftUI ⟩ Layout ⟩ Frame ⟩

⭐️ 重點

雖然 .frame(minWidth:idealWidth ...) 可以用來宣告 ideal size，但必須搭配 .fixedSize() 才會真正發生作用❗️

💈範例

• TestIdealSizeView - source code for the YouTube video above.

/*
     Intrinsic Content Size (ideal size):
     ------------------------------------
     🔸 1. define ideal size (SwiftUI won't respect it at first).
     🔸 2. use `.fixedSize()` to respect ideal size.
     🔸 3. use `.frame(width:height:) to override.
     🔸 4. can mix (2) / (3)
 */

struct ContentView: View {
    var body: some View {
        VStack {
            rect()
                .fixedSize()    // ⭐️ 2. respect ideal width/height
            rect(.blue)         // ⭐️ 2. respect ideal height
                .fixedSize(horizontal: false, vertical: true)
            rect(.orange)       // ⭐️ 2. respect ideal width
                .fixedSize(horizontal: true, vertical: false)
            rect(.purple)       // ⭐️ 3. override both
                .frame(width: 150, height: 20)
            rect(.green)        // ⭐️ 4. respect height, override width
                .fixedSize(horizontal: false, vertical: true)
                .frame(width: 200)
        }.padding()
    }
}

extension ContentView {
    func rect(_ color: Color = .pink) -> some View {
        Rectangle()
            .frame(idealWidth: 100, idealHeight: 100)    // 1.
            .foregroundColor(color)
    }
}

📘 手冊

• SwiftUI ⟩ Layout ⟩

  • Laying Out a Simple View

  • .frame(width:height:alignment:) - change proposed size.

  • .frame(minWidth:idealWidth:maxWidth ...) - define ideal size.

  • fixedSize(), fixedSize(horizontal:vertical:) - respect ideal size.

  • layoutPriority(_:)

📗 參考

• SwiftUI Lab ⟩ Frame Behaviors with SwiftUI

• Sarun ⟩ Intrinsic content size in SwiftUI ⭐️ (💈範例)

👥 相關

• stack