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iosswiftswiftuiinitializerviewbuilder

SwiftUI View: two different initializers: cannot convert value of type 'Text' to closure result type 'Content'


The code:

import SwiftUI

public struct Snackbar<Content>: View where Content: View {
    private var content: Content

// Works OK
    public init(@ViewBuilder content: () -> Content) {
        self.content = content()
    }

    init(_ text: String) {
        self.init {
            Text(text) // cannot convert value of type 'Text' to closure result type 'Content'
                .font(.subheadline)
                .foregroundColor(.white)
                .multilineTextAlignment(.leading)
        }
    }

    public var body: some View {
        HStack {
            VStack(alignment: .leading, spacing: 4) {
                content
            }
            Spacer()
        }
        .frame(maxWidth: .infinity,
               minHeight: 26)
        .padding(.fullPadding)
        .background(Color.black)
        .clipShape(RoundedRectangle(cornerRadius: .defaultCornerRadius))
        .shadow(color: Color.black.opacity(0.125), radius: 4, y: 4)
        .padding()
    }
}

I'm getting this error:

cannot convert value of type 'Text' to closure result type 'Content'

The goal I'm trying to achieve is to have 2 separate initializers, one for the content of type View and the other is a shortcut for a string, which will place a predefined Text component with some styling in place of Content.

Why am I getting this error if Text is some View and I think it should compile.


Solution

  • You can specify the type of Content.

    Code:

    public struct Snackbar<Content>: View where Content: View {
        private var content: Content
    
    // Works OK
        public init(@ViewBuilder content: () -> Content) {
            self.content = content()
        }
    
        init(_ text: String) where Content == ModifiedContent<Text, _EnvironmentKeyWritingModifier<TextAlignment>> {
            self.init {
                Text(text)
                    .font(.subheadline)
                    .foregroundColor(.white)
                    .multilineTextAlignment(.leading) as! ModifiedContent<Text, _EnvironmentKeyWritingModifier<TextAlignment>>
            }
        }
    
        /* ... */
    }
    

    The only difference here is the where after the init and the force-cast to the type inside the init.

    To avoid the specific type, you can abstract this into a separate view:

    init(_ text: String) where Content == ModifiedText {
        self.init {
            ModifiedText(text: text)
        }
    }
    
    /* ... */
    
    struct ModifiedText: View {
        let text: String
    
        var body: some View {
            Text(text)
                .font(.subheadline)
                .foregroundColor(.white)
                .multilineTextAlignment(.leading)
        }
    }