Custom fonts in Flutter - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the custom font family in the Text widget.

Flutter

Text('Hello, Flutter!', style: TextStyle(fontFamily: '[1]'))

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

ACourierNew

BArial

CTimesNewRoman

DRoboto

Attempts:

3 left

💡 Hint

Common Mistakes

Using a system font name instead of the custom font family.

Misspelling the font family name.

The fontFamily property in TextStyle sets the font to use. 'Roboto' is the custom font declared in pubspec.yaml.

2fill in blank

medium

Complete the pubspec.yaml snippet to include the custom font file.

Flutter

fonts:
  - family: Roboto
    fonts:
      - asset: [1]

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

Aassets/fonts/Roboto-Regular.ttf

Blib/fonts/Roboto-Regular.ttf

Cfonts/Roboto-Regular.ttf

Dassets/Roboto-Regular.ttf

Attempts:

3 left

💡 Hint

Common Mistakes

Incorrect folder path for the font file.

Forgetting to add the font file under assets in pubspec.yaml.

The font file path must match where you placed the font file in your project folder, usually under assets/fonts/.

3fill in blank

hard

Fix the error in the pubspec.yaml font declaration by completing the missing key.

Flutter

flutter:
  fonts:
    - family: Roboto
      [1]:
        - asset: assets/fonts/Roboto-Regular.ttf

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

Afonts

Bassets

Cfiles

Dsources

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong keys like 'assets' or 'files' instead of 'fonts'.

Indentation errors in pubspec.yaml.

The key 'fonts' is required to list the font asset files under a family in pubspec.yaml.

4fill in blank

hard

Fill both blanks to apply the custom font and set font size in TextStyle.

Flutter

Text('Custom Font', style: TextStyle(fontFamily: '[1]', fontSize: [2]))

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

ARoboto

B24.0

C18.0

DArial

Attempts:

3 left

💡 Hint

Common Mistakes

Using a system font name instead of the custom font.

Using fontSize as a string instead of a number.

Use the custom font family 'Roboto' and set fontSize to 24.0 for larger text.

5fill in blank

hard

Fill all three blanks to declare a custom font with regular and bold styles in pubspec.yaml.

Flutter

fonts:
  - family: [1]
    fonts:
      - asset: [2]
      - asset: [3]
        weight: 700

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

ARoboto

Bassets/fonts/Roboto-Regular.ttf

Cassets/fonts/Roboto-Bold.ttf

Dassets/fonts/Roboto-Italic.ttf

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing font file paths or using wrong weights.

Forgetting to indent properly in pubspec.yaml.

This declares the 'Roboto' font family with regular and bold font files. The bold font has weight 700.

Practice

1. What is the first step to use a custom font in a Flutter app?

easy

A. Add the font files to the assets folder and declare them in pubspec.yaml

B. Write the font name directly in the Text widget

C. Import a font package from pub.dev

D. Use the default system font without changes

Solution

1. Step 1: Add font files to assets

   You must first place your font files (like .ttf) inside an assets folder in your project.

2. Step 2: Declare fonts in pubspec.yaml

   Next, you declare these font files under the fonts section in pubspec.yaml so Flutter knows about them.

3. Final Answer:

   Add the font files to the assets folder and declare them in pubspec.yaml -> Option A

4. Quick Check:

   Custom fonts start with assets + pubspec.yaml declaration [OK]

Hint: Always start by adding font files and declaring in pubspec.yaml [OK]

Common Mistakes:

• Skipping pubspec.yaml declaration
• Trying to use font without adding files
• Using font name without quotes in TextStyle

2. Which of the following is the correct way to specify a custom font family in a Text widget's style?

easy

A. Text('Hello', style: TextStyle(fontStyle: 'MyFont'))

B. Text('Hello', style: TextStyle(font: 'MyFont'))

C. Text('Hello', style: TextStyle(fontName: 'MyFont'))

D. Text('Hello', style: TextStyle(fontFamily: 'MyFont'))

Solution

1. Step 1: Use fontFamily property in TextStyle

   The correct property to set a font family is fontFamily, not font, fontName, or fontStyle.

2. Step 2: Apply fontFamily in Text widget

   Use TextStyle(fontFamily: 'YourFontName') inside the style parameter of Text widget.

3. Final Answer:

   Text('Hello', style: TextStyle(fontFamily: 'MyFont')) -> Option D

4. Quick Check:

   fontFamily property sets custom font [OK]

Hint: Use fontFamily property inside TextStyle for custom fonts [OK]

Common Mistakes:

• Using font instead of fontFamily
• Confusing fontStyle with fontFamily
• Omitting quotes around font family name

3. Given this pubspec.yaml snippet:

fonts:
  - family: CoolFont
    fonts:
      - asset: assets/fonts/CoolFont-Regular.ttf
      - asset: assets/fonts/CoolFont-Bold.ttf
        weight: 700

What will this code display?

Text('Hi', style: TextStyle(fontFamily: 'CoolFont', fontWeight: FontWeight.bold))

medium

A. Text 'Hi' in CoolFont Bold style

B. Text 'Hi' in default font because fontWeight is ignored

C. Error because fontWeight 700 is invalid

D. Text 'Hi' in CoolFont Regular style ignoring bold

Solution

1. Step 1: Understand fontWeight mapping

   The pubspec.yaml declares two font assets: Regular (default weight) and Bold (weight 700).

2. Step 2: TextStyle uses fontWeight.bold

   Using fontWeight: FontWeight.bold matches weight 700, so Flutter uses the Bold font file.

3. Final Answer:

   Text 'Hi' in CoolFont Bold style -> Option A

4. Quick Check:

   fontWeight matches declared font weight for bold [OK]

Hint: Match fontWeight in TextStyle to declared font weights in pubspec.yaml [OK]

Common Mistakes:

• Ignoring fontWeight and expecting bold
• Assuming fontWeight 700 is invalid
• Not declaring font weights in pubspec.yaml

4. Why does this Flutter app fail to apply the custom font?

pubspec.yaml:
fonts:
  - family: FancyFont
    fonts:
      - asset: assets/fonts/FancyFont.ttf

Dart code:
Text('Hello', style: TextStyle(fontFamily: 'FancyFontt'))

medium

A. pubspec.yaml syntax error due to missing indentation

B. Font file is missing from assets folder

C. Font family name in TextStyle does not match pubspec.yaml

D. Text widget cannot use custom fonts

Solution

1. Step 1: Check fontFamily spelling in Dart code

   The Dart code uses 'FancyFontt' but pubspec.yaml declares 'FancyFont' (extra 't').

2. Step 2: Font family names must match exactly

   Font family names are case-sensitive and must match exactly between pubspec.yaml and Dart code.

3. Final Answer:

   Font family name in TextStyle does not match pubspec.yaml -> Option C

4. Quick Check:

   Font family names must match exactly [OK]

Hint: Check spelling of fontFamily matches pubspec.yaml exactly [OK]

Common Mistakes:

• Typos in font family names
• Forgetting to run flutter pub get after changes
• Incorrect indentation in pubspec.yaml

5. You want to use two different custom fonts in your Flutter app: 'Lobster' for titles and 'OpenSans' for body text. How should you organize your pubspec.yaml and Dart code to achieve this?

hard

A. Add both font files but use only one family name in pubspec.yaml

B. Declare both fonts under fonts in pubspec.yaml with different family names, then use fontFamily: 'Lobster' or 'OpenSans' in TextStyle accordingly

C. Declare only one font in pubspec.yaml and switch fontFamily names in Dart code

D. Use system fonts for titles and custom font for body text without declaring both

Solution

1. Step 1: Declare each font family separately in pubspec.yaml

   You must list each font family with its own name and font files under the fonts section.

2. Step 2: Use fontFamily property in Dart code for each Text widget

   Apply fontFamily: 'Lobster' for titles and fontFamily: 'OpenSans' for body text in TextStyle.

3. Final Answer:

   Declare both fonts under fonts in pubspec.yaml with different family names, then use fontFamily: 'Lobster' or 'OpenSans' in TextStyle accordingly -> Option B

4. Quick Check:

   Multiple fonts need separate declarations and usage [OK]

Hint: Declare each font family separately and use fontFamily accordingly [OK]

Common Mistakes:

• Declaring only one font family for multiple fonts
• Using wrong fontFamily names in Dart code
• Not adding all font files to assets