How to Fix SwiftUI List Not Displaying Correctly

In this tutorial, you'll learn about How to Fix SwiftUI List Not Displaying Correctly. We cover key concepts, practical examples, and best practices.

The Problem

SwiftUI List is not working as expected:

List content is empty or not updating.

Quick Fix

Step 1: Use the correct data source

WRONG — passing a non-Identifiable type:

struct Item {
    let name: String
}

List(items, id: \.name) { item in  // OK but requires explicit id
    Text(item.name)
}

RIGHT — use Identifiable:

struct Item: Identifiable {
    let id = UUID()
    let name: String
}

List(items) { item in
    Text(item.name)
}

Step 2: Use ForEach inside List

List {
    Section("Fruits") {
        ForEach(fruits) { fruit in
            Text(fruit.name)
        }
    }
    Section("Vegetables") {
        ForEach(vegetables) { vegetable in
            Text(vegetable.name)
        }
    }
}

Step 3: Enable dynamic updates

@State private var items = [Item(name: "Apple"), Item(name: "Banana")]

var body: some View {
    List {
        ForEach(items) { item in
            Text(item.name)
        }
        .onDelete { indexSet in
            items.remove(atOffsets: indexSet)
        }
    }
}

Step 4: Add pull-to-refresh

List(items) { item in
    Text(item.name)
}
.refreshable {
    await refreshItems()
}

Step 5: Style the list

List(items) { item in
    Text(item.name)
}
.listStyle(.insetGrouped)  // .plain, .grouped, .inset, .insetGrouped

Step 6: Use LazyVStack for custom layouts

ScrollView {
    LazyVStack {
        ForEach(items) { item in
            Text(item.name)
                .padding()
        }
    }
}

Prevention

• Always make list items conform to Identifiable.
• Use ForEach inside List for dynamic content with actions.
• Use .refreshable for pull-to-refresh instead of UIKit integration.

Common Mistakes with swiftui list

1. Non-exhaustive pattern matches that compile with warnings then crash at runtime
2. Misunderstanding that String is [Char] with poor performance for large text operations
3. Using foldl instead of foldl' causing stack overflow on large lists

These mistakes appear frequently in real-world IOS code. DodaTech's contributors have identified these patterns through analysis of open-source projects and production systems.

Practice Exercise

Write a pure function that safely divides two integers using Maybe, then test it with edge cases like division by zero and negative numbers.

This exercise reinforces the concepts covered in this guide. Try implementing it before checking online solutions.

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