Search with searchable modifier in iOS Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a search bar to the list.

iOS Swift

List(items, id: \.self) { item in
    Text(item)
}
.[1](text: $searchText)

Drag options to blanks, or click blank then click option'

AsearchBar

Bsearch

Csearchable

DsearchField

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'search' instead of 'searchable' causes a compiler error.

Trying to use 'searchBar' which is not a SwiftUI modifier.

The searchable modifier adds a search bar to the list.

2fill in blank

medium

Complete the code to declare the search text state variable.

iOS Swift

@State private var [1] = ""

Drag options to blanks, or click blank then click option'

AsearchText

BsearchTerm

Cquery

DfilterText

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different variable name without updating the binding causes the search bar not to work.

The variable searchText is commonly used to hold the search input.

3fill in blank

hard

Fix the error in filtering the list based on search text.

iOS Swift

let filteredItems = items.filter { item in
    item.lowercased().contains([1].lowercased())
}

Drag options to blanks, or click blank then click option'

Aquery

BsearchText

CsearchTerm

DfilterText

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name that is not declared causes a compile error.

Using the wrong variable name breaks the filtering logic.

The filter uses searchText to check if the item contains the search input.

4fill in blank

hard

Fill both blanks to create a filtered list that updates with search text.

iOS Swift

List([1]) { item in
    Text(item)
}
.searchable(text: $[2])

Drag options to blanks, or click blank then click option'

AfilteredItems

Bitems

CsearchText

DsearchTerm

Attempts:

3 left

💡 Hint

Common Mistakes

Showing all items instead of filtered items.

Binding searchable to a wrong variable.

The list shows filteredItems and binds the search bar to searchText.

5fill in blank

hard

Fill all three blanks to complete the search filtering logic.

iOS Swift

let filteredItems = [1].filter { item in
    item.[2]().contains(searchText.[3]())
}

Drag options to blanks, or click blank then click option'

Aitems

Blowercased

Cuppercased

Dcapitalized

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong array name causes errors.

Not using consistent casing causes search mismatches.

The filtering uses items and compares lowercase strings for case-insensitive search.

Practice

1. What does the searchable modifier do in a SwiftUI view?

easy

A. Removes all items from the list when typing.

B. Automatically sorts the list items alphabetically.

C. Changes the background color of the list.

D. Adds a search bar to filter content in lists or scroll views.

Solution

1. Step 1: Understand the purpose of searchable

   The searchable modifier adds a search bar UI element to a list or scroll view.

2. Step 2: Identify its effect on content

   It allows users to type text to filter or search through the displayed content.

3. Final Answer:

   Adds a search bar to filter content in lists or scroll views. -> Option D

4. Quick Check:

   searchable = search bar added [OK]

Hint: searchable always adds a search bar UI [OK]

Common Mistakes:

• Thinking searchable sorts items automatically
• Confusing searchable with styling modifiers
• Assuming searchable removes items without filtering

2. Which of the following is the correct syntax to add a searchable modifier with a binding to a @State variable named searchText?

easy

A. .searchable(searchText)

B. .searchable($searchText)

C. .searchable(text: $searchText)

D. .searchable(text: searchText)

Solution

1. Step 1: Recall the searchable syntax

   The searchable modifier requires a binding to a string, written as text: $variable.

2. Step 2: Match the correct binding syntax

   Using $searchText passes the binding, so the correct syntax is .searchable(text: $searchText).

3. Final Answer:

   .searchable(text: $searchText) -> Option C

4. Quick Check:

   Binding uses $ with variable name [OK]

Hint: Use $ to bind @State variable in searchable [OK]

Common Mistakes:

• Omitting the text: label
• Not using $ for binding
• Passing variable without binding

3. Given this SwiftUI code snippet, what will be displayed when the user types "ap" in the search bar?

struct ContentView: View {
  @State private var searchText = ""
  let fruits = ["Apple", "Banana", "Grape", "Apricot"]

  var filteredFruits: [String] {
    if searchText.isEmpty { return fruits }
    return fruits.filter { $0.lowercased().contains(searchText.lowercased()) }
  }

  var body: some View {
    List(filteredFruits, id: \.self) { fruit in
      Text(fruit)
    }
    .searchable(text: $searchText)
  }
}

medium

A. ["Apple", "Apricot"]

B. ["Banana", "Grape"]

C. ["Apple", "Banana", "Grape", "Apricot"]

D. Empty list

Solution

1. Step 1: Understand filtering logic

   The filter checks if each fruit contains the search text "ap" ignoring case.

2. Step 2: Apply filter to fruits list

   "Apple" and "Apricot" contain "ap" (case-insensitive), "Banana" and "Grape" do not match exactly.

3. Final Answer:

   ["Apple", "Apricot"] -> Option A

4. Quick Check:

   Filter by contains "ap" = Apple, Apricot [OK]

Hint: Filter checks contains ignoring case [OK]

Common Mistakes:

• Including fruits that don't contain "ap"
• Ignoring case sensitivity
• Returning full list regardless of search

4. Identify the error in this SwiftUI code using searchable:

struct ContentView: View {
  @State var searchText = ""
  let items = ["One", "Two", "Three"]

  var filteredItems: [String] {
    items.filter { $0.contains(searchText) }
  }

  var body: some View {
    List(filteredItems, id: \.self) { item in
      Text(item)
    }
    .searchable(text: searchText)
  }
}

medium

A. Missing $ to bind searchText in searchable modifier.

B. filteredItems should be a @State variable.

C. List requires a ForEach instead of direct array.

D. searchText should be a constant, not @State.

Solution

1. Step 1: Check searchable binding syntax

   The searchable modifier requires a binding, so it must be text: $searchText, not text: searchText.

2. Step 2: Verify other code parts

   filteredItems is computed correctly, List accepts array with id, and searchText should be @State.

3. Final Answer:

   Missing $ to bind searchText in searchable modifier. -> Option A

4. Quick Check:

   Binding needs $ prefix [OK]

Hint: Always use $ for @State binding in searchable [OK]

Common Mistakes:

• Forgetting $ in searchable binding
• Making filteredItems @State unnecessarily
• Confusing List requirements

5. You want to create a searchable list of contacts where typing filters by first or last name. Which code snippet correctly implements this behavior?

struct Contact: Identifiable {
  let id = UUID()
  let firstName: String
  let lastName: String
}

struct ContentView: View {
  @State private var searchText = ""
  let contacts = [Contact(firstName: "John", lastName: "Doe"), Contact(firstName: "Jane", lastName: "Smith"), Contact(firstName: "Alice", lastName: "Johnson")]

  var filteredContacts: [Contact] {
    if searchText.isEmpty { return contacts }
    return contacts.filter { contact in
      contact.firstName.lowercased().contains(searchText.lowercased()) || contact.lastName.lowercased().contains(searchText.lowercased())
    }
  }

  var body: some View {
    List(filteredContacts) { contact in
      Text("\(contact.firstName) \(contact.lastName)")
    }
    .searchable(text: $searchText)
  }
}

hard

A. Filters contacts only by first name and ignores last name.

B. Filters contacts by first or last name ignoring case and updates list dynamically.

C. Filters contacts but does not ignore case, so search is case-sensitive.

D. Does not filter contacts and always shows full list.

Solution

1. Step 1: Analyze filtering logic

   The filter checks if either firstName or lastName contains the search text, ignoring case.

2. Step 2: Confirm UI updates with searchable

   The searchable modifier binds to $searchText, so typing updates the filteredContacts list dynamically.

3. Final Answer:

   Filters contacts by first or last name ignoring case and updates list dynamically. -> Option B

4. Quick Check:

   Filter by first or last name, case-insensitive [OK]

Hint: Filter with OR condition and ignore case for full search [OK]

Common Mistakes:

• Filtering only by first name
• Not using lowercased() causing case sensitivity
• Forgetting to bind searchText with $