Creating a custom UIView using Xib

CustomUIView

Steps for creating custom UIView.

1. Create a xib file, eg: MyCustomView.xib
2. Do necessary layout in xib file 
3. Create a UIView file. eg: MyCustomView.swift. 
4. Set this MyCustomView.swift file as the file owner of that xib
5. Create necessary outlets from the .xib file to .swift file. Important: Create one outlet for the root parent UIView to .swift file. 
Name this outlet as as containerView
6. Override both the init method i.e using decoder & frame
7. Set the code as follows

    override init(frame: CGRect) {
        super.init(frame: frame)
        
        setupXib()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        
        setupXib()
    }
    
    override func layoutSubviews() {
        super.layoutSubviews()
        
        self.containerView.frame = bounds
    }
    
    func setupXib() {
        
        // 1. Load the nib
        self.containerView = Bundle.main.loadNibNamed(WorkoutSetInputView.stringIdentifier, owner: self, options: nil)![0] as! UIView
        
        // 2. Set the bounds for the container view
        self.containerView.frame = bounds
        self.containerView.autoresizingMask = [.flexibleWidth,.flexibleHeight]
        
        // 3. Add this container view as the subview
        addSubview(containerView)
    }