Variables in prototypes in Figma - Cell-by-Cell Formula Trace

Sample Data

This table shows variables defined in a Figma prototype with their current values.

Cell	Value
A1	Variable Name
B1	Value
A2	UserName
B2	Alice
A3	UserAge
B3	30
A4	UserStatus
B4	Active

Formula Trace

Set variable UserGreeting = "Hello, " + UserName + "!"

Step 1: "Hello, " + UserName + "!"

Step 2: UserGreeting = "Hello, Alice!"

Cell Reference Map

  A          B
1 Variable   Value
2 UserName -> Alice
3 UserAge    30
4 UserStatus Active

The formula uses the variable UserName from cell B2 with value 'Alice' to build the greeting.

Result

  A             B
1 Variable    Value
2 UserName   Alice
3 UserAge    30
4 UserStatus Active
5 UserGreeting Hello, Alice!

The new variable UserGreeting is added with the value 'Hello, Alice!' after evaluating the formula.

Sheet Trace Quiz - 3 Questions

What value does the variable UserGreeting hold after evaluation?

A "Hello, UserName!"

B "Alice!"

C "Hello, Alice!"

D "Hello!"

Key Result

Concatenate strings and variables to create dynamic text in prototypes.

Practice

1. What is the main purpose of using variables in Figma prototypes?

easy

A. To store information that makes prototypes interactive

B. To change the color of shapes automatically

C. To export images faster

D. To create new pages in the file

Solution

1. Step 1: Understand what variables do in prototypes

   Variables hold data like numbers or text to change prototype behavior dynamically.

2. Step 2: Identify the correct purpose

   Among the options, only storing information for interactivity matches variables' role.

3. Final Answer:

   To store information that makes prototypes interactive -> Option A

4. Quick Check:

   Variables = store info for interactivity [OK]

Hint: Variables store data to make prototypes respond [OK]

Common Mistakes:

• Thinking variables change colors automatically
• Confusing variables with exporting features
• Assuming variables create new pages

2. Which of the following is the correct syntax to set a variable named score to 10 in a Figma prototype?

easy

A. Set(score, 10)

B. Set(score = 10)

C. Set("score", 10)

D. Set('score' = 10)

Solution

1. Step 1: Recall the syntax for setting variables

   Variables require the name as a string in quotes and the value separated by a comma.

2. Step 2: Compare options

   Only Set("score", 10) uses quotes around the variable name and a comma to separate name and value.

3. Final Answer:

   Set("score", 10) -> Option C

4. Quick Check:

   Set("name", value) syntax [OK]

Hint: Variable names need quotes in Set() function [OK]

Common Mistakes:

• Omitting quotes around variable name
• Using equals sign instead of comma
• Using single quotes incorrectly

3. Given the variable count is set to 3, what will be displayed if the text element contains: You clicked {{count}} times?

medium

A. You clicked 0 times

B. You clicked {{count}} times

C. You clicked times 3

D. You clicked 3 times

Solution

1. Step 1: Understand variable usage in text

   The syntax {{count}} replaces with the current value of the variable count.

2. Step 2: Substitute the value

   Since count = 3, the text becomes "You clicked 3 times".

3. Final Answer:

   You clicked 3 times -> Option D

4. Quick Check:

   {{count}} = 3 substitution [OK]

Hint: {{variable}} shows current variable value in text [OK]

Common Mistakes:

• Leaving {{count}} as is without substitution
• Mixing order of words
• Assuming variable is zero if not set

4. You wrote Set(count 5) to set a variable but it doesn't work. What is the error?

medium

A. Missing comma between variable name and value

B. Variable name should not be in quotes

C. Value must be a string, not a number

D. Set function cannot set numbers

Solution

1. Step 1: Check the Set() function syntax

   Set() requires two arguments separated by a comma: name and value.

2. Step 2: Identify the missing comma

   The code misses the comma between count and 5, causing syntax error.

3. Final Answer:

   Missing comma between variable name and value -> Option A

4. Quick Check:

   Set(name, value) needs comma [OK]

Hint: Remember comma separates name and value in Set() [OK]

Common Mistakes:

• Forgetting the comma
• Using wrong quotes around variable name
• Thinking numbers can't be set

5. You want to create a prototype that counts how many times a button is clicked. Which sequence correctly updates and shows the count using variables?

hard

A. Set("count", 1) on start; on click: Set("count", 1); display text: "Clicked {{count}} times"

B. Set("count", 0) on start; on click: Set("count", {{count}} + 1); display text: "Clicked {{count}} times"

C. Set(count, 0) on start; on click: Set(count, count + 1); display text: "Clicked count times"

D. Set("count", 0) on start; on click: Set("count", count + 1); display text: "Clicked {{count}} times"

Solution

1. Step 1: Initialize the count variable correctly

   Use Set("count", 0) with quotes around name to start at zero.

2. Step 2: Update count on click using current value plus one

   Use Set("count", {{count}} + 1) to add one to current count value.

3. Step 3: Display the count using {{count}} syntax

   Text must use "Clicked {{count}} times" to show updated count.

4. Final Answer:

   Set("count", 0) on start; on click: Set("count", {{count}} + 1); display text: "Clicked {{count}} times" -> Option B

5. Quick Check:

   Initialize, increment with {{count}}, display with {{count}} [OK]

Hint: Initialize zero, increment with {{count}} + 1, display with {{count}} [OK]

Common Mistakes:

• Not using quotes around variable name
• Not referencing variable with {{}} when updating
• Displaying variable name without {{}} in text