Why animations polish user experience in iOS Swift - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to animate a view's opacity change smoothly.

iOS Swift

UIView.animate(withDuration: 1.0) {
  myView.alpha = [1]
}

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

A-1

B1.5

C0.5

D2

Attempts:

3 left

💡 Hint

Common Mistakes

Using values greater than 1 or negative values causes no visible animation or errors.

The alpha property controls opacity from 0 (transparent) to 1 (opaque). Using 0.5 fades the view to half transparency smoothly.

2fill in blank

medium

Complete the code to animate a view's position change using a spring effect.

iOS Swift

UIView.animate(withDuration: 1.0, delay: 0, usingSpringWithDamping: [1], initialSpringVelocity: 0, options: [], animations: {
  myView.center.x += 100
}, completion: nil)

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A2.0

B-0.5

C1.5

D0.5

Attempts:

3 left

💡 Hint

Common Mistakes

Using values greater than 1 or negative values disables spring effect.

The damping ratio controls springiness. Values between 0 and 1 create a spring effect. 0.5 gives a nice bounce.

3fill in blank

hard

Fix the error in the animation block to correctly animate background color change.

iOS Swift

UIView.animate(withDuration: 0.5) {
  myView.backgroundColor = [1]
}

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AUIColor.red

BUIColor.redColor()

CredColor()

Dcolor.red

Attempts:

3 left

💡 Hint

Common Mistakes

Using Objective-C style methods like redColor() causes errors.

In Swift, UIColor.red is the correct way to access the red color. redColor() is Objective-C style and not valid here.

4fill in blank

hard

Fill both blanks to animate a view's scale transform to double size and back.

iOS Swift

UIView.animate(withDuration: 0.3, animations: {
  myView.transform = CGAffineTransform.[1](x: 2.0, y: 2.0)
}) { _ in
  UIView.animate(withDuration: 0.3) {
    myView.transform = CGAffineTransform.[2]()
  }
}

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

Ascale

Btranslate

Cidentity

Drotate

Attempts:

3 left

💡 Hint

Common Mistakes

Using translate or rotate instead of scale causes wrong animation.

Use CGAffineTransform.scale to enlarge the view, and CGAffineTransform.identity to reset it back to original size.

5fill in blank

hard

Fill all three blanks to animate a view's position, opacity, and background color change together.

iOS Swift

UIView.animate(withDuration: 1.0) {
  myView.center.x += [1]
  myView.alpha = [2]
  myView.backgroundColor = UIColor.[3]
}

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

A50

B0.3

Cblue

D100

Attempts:

3 left

💡 Hint

Common Mistakes

Using alpha values outside 0-1 or invalid color names causes errors.

Moving the view 100 points right, fading to 0.3 opacity, and changing background color to blue creates a smooth combined animation.