Added delegate

Author: Bob Lee

source-code/4000_protocol_oriented_swift/.DS_Store

@@ -4,13 +4,15 @@
  ### Protocol Oriented Swift
  ### Delegate
 
- **Problem:** Communicate between classes and structs
+ **Problem:** How does delegate even work?
 
  ---
  */
-//: Delegate
-//: 1. A gift from Apple engineers
-//: 2. microwave analogy
+
+//: > **Purpose of Delegate:** Communicate between objects
+
+
+//: **Goal:** Send data from `FirstVC` to `SecondVC`
 
 //: Design Protocol
 protocol PassDataDelegate {
@@ -20,16 +22,17 @@ protocol PassDataDelegate {
 
 //: Design Delegator (Sender)
 class FirstVC {
+ func drawCircle() {}
  var delegate: PassDataDelegate?
 }
 
-FirstVC().delegate?.passData(data: "Bob")
+FirstVC().delegate?.passData(data: "A bunch of contracts")
 
 
 //: Design Delegate (Receiver)
 class SecondVC: PassDataDelegate {
  func passData(data: String) {
- print("Something happened")
+ print("The CEO gave me \(data)")
  }
 }
 
@@ -40,17 +43,32 @@ let secondVC = SecondVC()
 
 //: Assign Delegate
 firstVC.delegate = secondVC
-firstVC.delegate?.passData(data: "Hello, 1231231") 
-
+firstVC.delegate?.passData(data: "A bunch of contracts")
 
 
 
 
+//: Practical Example in iOS
+import UIKit
 
+class BobViewController: UIViewController, UITableViewDelegate {
+ let tableView = UITableView()
+ override func viewDidLoad() {
+ super.viewDidLoad()
+ tableView.delegate = self
+ }
+ 
+ func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
+ print(indexPath)
+ }
+}
 
 
+//: tableView.delegate.tableView(_ tableView: UITableView, didSelectRorwAt indexPath: IndexPath)
 
 
+// UITableView is the delegator/CEO/sender
+// BobViewController is the delegate/Secretary/receiver
 
 
 

source-code/4000_protocol_oriented_swift/4004_delegate.playground/Contents.swift

@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<playground version='5.0' target-platform='ios' display-mode='raw'>
+<playground version='5.0' target-platform='ios' display-mode='rendered'>
  <timeline fileName='timeline.xctimeline'/>
 </playground>