Resize uiscrollview after adding content programmatically

Question

I have an Contentview with uielements inside Uiscrollview. Below screenshot of my storyboard:

I want to add the option for the app that if the user clicks the button it will add label on the bottom of the contentview (below red underscored label - dzialTerminOutlet).

I'm adding the new label programmatically using following code:

let label = UILabel()
label.translatesAutoresizingMaskIntoConstraints = false

label.backgroundColor = UIColor.orange
label.textColor = UIColor.black
label.textAlignment = NSTextAlignment.center
label.text = "test label"
contentView.addSubview(label)


label.topAnchor.constraint(equalTo: dzialTerminOutlet.bottomAnchor, constant: 10).isActive = true
label.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: 85.0)
label.widthAnchor.constraint(equalToConstant: 200.0)
label.heightAnchor.constraint(equalToConstant: 10.0)

The scrollview does not resize though. What's the issue here?

Shehata Gamal · Accepted Answer · 2018-10-12 17:07:35Z

1

1- You need to activate

NSLayoutConstraint.activate([
  label.topAnchor.constraint(equalTo: dzialTerminOutlet.bottomAnchor, constant: 10),
  label.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: 85.0),
  label.widthAnchor.constraint(equalToConstant: 200.0),
  label.heightAnchor.constraint(equalToConstant: 10.0)
])

2- You need to remove the bottom constraint established in IB between dzialTerminOutlet and contentView to be able to insert the new one and make the scrollView resize accordingly to avoid conflicts between it and

label.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: 85.0)

so hook it as an outlet and deactivate it or search contentView for the bottom constraint and remove it

answered Oct 12, 2018 at 17:07

Shehata Gamal

101k8 gold badges75 silver badges95 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

mik.ro Over a year ago

Your answer seems very logic to me. However after i disable the bottom contraint (dzialTerminBottomConstraint.isActive = false) the scrollview gets shorter by 85 px.

Shehata Gamal Over a year ago

make it -85 (minus)

User18474728 · Accepted Answer · 2018-10-12 17:04:33Z

0

Did you set scrollView contentSize with new size? scrollView.contentSize = CGSize(width: self.contentView.frame.size.width, height: self.contentView.frame.size.height)

answered Oct 12, 2018 at 17:04

User18474728

3612 silver badges12 bronze badges

Comments

Naser Mohamed · Accepted Answer · 2018-10-12 17:26:18Z

0

a very simple way i'm using it a lot is to connect your contentView height constraint with an IBOutlet object and update it's value.

@IBOutlet weak var contentViewHeight : NSLayoutConstraint!

And after adding your label:

contentViewHeight.constant += labelHeight

Don't forget to set the contentView constraint (top, bottom, leading, trailing) = 0 with scroll view

answered Oct 12, 2018 at 17:26

Naser Mohamed

1466 bronze badges

Collectives™ on Stack Overflow

Resize uiscrollview after adding content programmatically

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related