嗨，試圖創建一個僅具有背景漸變的可重用組件，但在預覽中出現錯誤
這是組件
import SwiftUI
struct Patterns<Content: View>: View {
@ViewBuilder var content: Content
var body: some View {
ZStack {
LinearGradient(
gradient: Gradient(
colors: [Color.red, Color.blue]
), startPoint: .leading, endPoint: .trailing)
content
}
}
}
struct Patterns_Previews: PreviewProvider {
static var previews: some View {
Patterns {
Text("Hello")
}
}
}
但預覽看起來像這樣
uj5u.com熱心網友回復：
視圖構建器實際上是函式生成視圖的包裝器，因此這里是固定變體：
struct Patterns<Content: View>: View {
@ViewBuilder var content: () -> Content // << here !!
var body: some View {
ZStack {
LinearGradient(
gradient: Gradient(
colors: [Color.red, Color.blue]
), startPoint: .leading, endPoint: .trailing)
content() // << here !!
}
}
}
使用 Xcode 13.2 / iOS 15.2 測驗
轉載請註明出處，本文鏈接：https://www.uj5u.com/qukuanlian/401143.html
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