Template for custom view loaded from a .xib file

CustomView.swift

//
//  CustomView.swift
//
//  Created by Rigoberto Sáenz Imbacuán (https://www.linkedin.com/in/rsaenzi/)
//  Copyright © 2019. All rights reserved.
//

// Notes:
// - Bind content to the ContentView in Interface Builder
// - Make the xib's file owner be this class

import UIKit

class CustomView: UIView {
   
    // This property must be bound to the whole view in Interface Builder
    @IBOutlet private weak var content: UIView!
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        sharedInit()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        sharedInit()
    }
    
    private func sharedInit() {
        loadNib()
        addSubview(content)
        
        // Expand to fill its parent
        content.frame = self.bounds
        content.autoresizingMask = [.flexibleHeight, .flexibleWidth]
    }
}

CustomCell.swift
https://gist.github.com/rsaenzi/e2ab2c4e78ee7ba12c9b534ec4982530