how to create function that return NSLayoutConstraint

Question

hey developer I want to ask, I have a repeated create constraint and then I try to create a function that return NSLayoutConstraint. then I got confuse what should I return since there is 3 different UIView in my function. here I show you my code.

NSLayoutConstraint.activate([
            subtitlebl.topAnchor.constraint(equalTo: contentView.topAnchor, constant: 0),
            subtitlebl.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 18),

            profileImageView.topAnchor.constraint(equalTo: subtitlebl.bottomAnchor, constant: 24),
            profileImageView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 18),
            profileImageView.widthAnchor.constraint(equalToConstant: 68),
            profileImageView.heightAnchor.constraint(equalToConstant: 68),

            editButton.topAnchor.constraint(equalTo: subtitlebl.bottomAnchor, constant: 49),
            editButton.leadingAnchor.constraint(equalTo: profileImageView.trailingAnchor, constant: 12),
            editButton.widthAnchor.constraint(equalToConstant: 104),
            editButton.heightAnchor.constraint(equalToConstant: 20),

            profileNameStackView.topAnchor.constraint(equalTo: profileImageView.bottomAnchor, constant: 30),
            profileNameStackView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24),
            profileNameStackView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -24),
            profileNameStackView.heightAnchor.constraint(equalToConstant: 74),

            phoneStackView.topAnchor.constraint(equalTo: profileNameStackView.bottomAnchor, constant: 30),
            phoneStackView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24),
            phoneStackView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -24),
            phoneStackView.heightAnchor.constraint(equalToConstant: 74),

            createStackViewConstraint(stackView: profileNameStackView, topStackView: profileImageView, label: profileNameLbl, textFIeld: profileNameTextField)
)]

   private func createStackViewConstraint(stackView: UIStackView, topStackView: UIView, label: UILabel, textFIeld: UITextField) -> NSLayoutConstraint {
       stackView.topAnchor.constraint(equalTo: topStackView.bottomAnchor, constant: 30).isActive = true
       stackView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24).isActive = true
       stackView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -24).isActive = true
       stackView.heightAnchor.constraint(equalToConstant: 74).isActive = true

       label.heightAnchor.constraint(equalToConstant: 18).isActive = true
       textFIeld.heightAnchor.constraint(equalToConstant: 48).isActive = true
    }

Answer 1

good job, But there are few mistakes in your code.

• you add return type to your function.Adding constraints to some component is Void type.It will return nothing.(so remove it)
• you add profileNameStackView constraints in NSLayoutConstraint.activate and call your function to add again.

try this, make sure your your components

translatesAutoresizingMaskIntoConstraints = false

 NSLayoutConstraint.activate([
                subtitlebl.topAnchor.constraint(equalTo: contentView.topAnchor, constant: 0),
                subtitlebl.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 18),

                profileImageView.topAnchor.constraint(equalTo: subtitlebl.bottomAnchor, constant: 24),
                profileImageView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 18),
                profileImageView.widthAnchor.constraint(equalToConstant: 68),
                profileImageView.heightAnchor.constraint(equalToConstant: 68),

                editButton.topAnchor.constraint(equalTo: subtitlebl.bottomAnchor, constant: 49),
                editButton.leadingAnchor.constraint(equalTo: profileImageView.trailingAnchor, constant: 12),
                editButton.widthAnchor.constraint(equalToConstant: 104),
                editButton.heightAnchor.constraint(equalToConstant: 20),

    )]
    //add constraints to profileNameStackView
    createStackViewConstraint(stackView: profileNameStackView, topStackView: profileImageView, label: profileNameLbl, textFIeld: profileNameTextField)


    //add constraints to phoneStackView
    createStackViewConstraint(stackView: phoneStackView, topStackView: profileNameStackView, label: phoneLbl, textFIeld: phoneTextField)


//your function
       private func createStackViewConstraint(stackView: UIStackView, topStackView: UIView, label: UILabel, textFIeld: UITextField) -> NSLayoutConstraint {
           stackView.topAnchor.constraint(equalTo: topStackView.bottomAnchor, constant: 30).isActive = true
           stackView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24).isActive = true
           stackView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -24).isActive = true
           stackView.heightAnchor.constraint(equalToConstant: 74).isActive = true

           label.heightAnchor.constraint(equalToConstant: 18).isActive = true
           textFIeld.heightAnchor.constraint(equalToConstant: 48).isActive = true
        }