Designed the Add Transaction view

Budget Tracker/AddTransactionViewController.swift

@@ -7,14 +7,109 @@
 
 import UIKit
 
-class AddTransactionViewController: UIViewController {
-
+class AddTransactionViewController: UIViewController, UITextFieldDelegate {
+    @IBOutlet weak var addButton: UIBarButtonItem!
+    @IBOutlet weak var categoryTextField: UITextField!
+    @IBOutlet weak var nameTextField: UITextField!
+    @IBOutlet weak var costTextField: UITextField!
+    var doneButton: UIBarButtonItem!
+    
     override func viewDidLoad() {
         super.viewDidLoad()
+        addButton.isEnabled = false
+        categoryTextField.delegate = self
+        nameTextField.delegate = self
+        costTextField.delegate = self
+        addDoneButtonToKeyboard(myAction:  #selector(costTextField.resignFirstResponder))
+        NotificationCenter.default.addObserver(self,
+                    selector: #selector(AddTransactionViewController.keyboardWillShow),
+                    name: UIResponder.keyboardWillShowNotification, object: nil)
+        NotificationCenter.default.addObserver(self,
+                    selector: #selector(AddTransactionViewController.keyboardWillHide),
+                    name: UIResponder.keyboardWillHideNotification, object: nil)
+    }
+    
+    @IBAction func addTransactions(_ sender: UIBarButtonItem) {
+        dismiss(animated: true, completion: nil)
     }
     
-    @IBAction func cancel(_ sender: UIButton) {
+    @IBAction func cancel(_ sender: UIBarButtonItem) {
         dismiss(animated: true, completion: nil)
     }
     
+    func textFieldDidBeginEditing(_ textField: UITextField) {
+        addButton.isEnabled = false
+    }
+    
+    func textFieldDidChangeSelection(_ textField: UITextField) {
+        let text = costTextField.text ?? ""
+        if text.isEmpty {
+            doneButton.isEnabled = false
+        } else {
+            doneButton.isEnabled = true
+        }
+    }
+    
+    func textFieldDidEndEditing(_ textField: UITextField) {
+        updateAddButtonStatus()
+    }
+    
+    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
+        categoryTextField.resignFirstResponder()
+        nameTextField.resignFirstResponder()
+        return true
+    }
+    
+    private func updateAddButtonStatus() {
+        var text = categoryTextField.text ?? ""
+        if text.isEmpty {
+            addButton.isEnabled = false
+            return
+        }
+        text = nameTextField.text ?? ""
+        if text.isEmpty {
+            addButton.isEnabled = false
+            return
+        }
+        text = costTextField.text ?? ""
+        if text.isEmpty {
+            addButton.isEnabled = false
+            return
+        }
+        addButton.isEnabled = true
+    }
+    
+    private func addDoneButtonToKeyboard(myAction:Selector?){
+        let doneToolbar: UIToolbar = UIToolbar(frame: CGRect(x: 0, y: 0, width: 300, height: 40))
+        doneToolbar.barStyle = UIBarStyle.default
+        let flexSpace = UIBarButtonItem(barButtonSystemItem:
+                                        UIBarButtonItem.SystemItem.flexibleSpace, target: nil, action: nil)
+        doneButton = UIBarButtonItem(
+            title: "Done", style: UIBarButtonItem.Style.done, target: costTextField, action: myAction)
+        doneButton.isEnabled = false
+        var items = [UIBarButtonItem]()
+        items.append(flexSpace)
+        items.append(doneButton)
+        doneToolbar.items = items
+        doneToolbar.sizeToFit()
+        costTextField.inputAccessoryView = doneToolbar
+     }
+    
+    @objc func keyboardWillShow(notification: NSNotification) {
+        guard let userInfo = notification.userInfo else {return}
+        guard let keyboardSize = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else {return}
+        let keyboardFrame = keyboardSize.cgRectValue
+        if costTextField.isEditing && costTextField.frame.origin.y + costTextField.frame.height
+            > self.view.frame.height - keyboardFrame.height {
+            self.view.frame.origin.y = -costTextField.frame.origin.y - costTextField.frame.height
+                                            + self.view.frame.height - keyboardFrame.height - 20
+        }
+    }
+    
+    @objc func keyboardWillHide(notification: NSNotification) {
+        if self.view.frame.origin.y != 0 {
+            self.view.frame.origin.y = 0
+        }
+    }
+    
 }

Budget Tracker/Assets.xcassets/AppIcon.appiconset/Contents.json

 {
   "images" : [
     {
+      "filename" : "Icon-App-40x40@1x.png",
       "idiom" : "iphone",
       "scale" : "2x",
       "size" : "20x20"
     },
     {
+      "filename" : "Icon-App-20x20@3x.png",
       "idiom" : "iphone",
       "scale" : "3x",
       "size" : "20x20"
     },
     {
+      "filename" : "Icon-App-29x29@2x.png",
       "idiom" : "iphone",
       "scale" : "2x",
       "size" : "29x29"
     },
     {
+      "filename" : "Icon-App-29x29@3x.png",
       "idiom" : "iphone",
       "scale" : "3x",
       "size" : "29x29"
     },
     {
+      "filename" : "Icon-App-40x40@2x.png",
       "idiom" : "iphone",
       "scale" : "2x",
       "size" : "40x40"
     },
     {
+      "filename" : "Icon-App-40x40@3x.png",
       "idiom" : "iphone",
       "scale" : "3x",
       "size" : "40x40"
     },
     {
+      "filename" : "Icon-App-60x60@2x.png",
       "idiom" : "iphone",
       "scale" : "2x",
       "size" : "60x60"
     },
     {
+      "filename" : "Icon-App-60x60@3x.png",
       "idiom" : "iphone",
       "scale" : "3x",
       "size" : "60x60"
     },
     {
+      "filename" : "Icon-App-20x20@1x.png",
       "idiom" : "ipad",
       "scale" : "1x",
       "size" : "20x20"
     },
     {
+      "filename" : "Icon-App-20x20@2x.png",
       "idiom" : "ipad",
       "scale" : "2x",
       "size" : "20x20"
     },
     {
+      "filename" : "Icon-App-29x29@1x.png",
       "idiom" : "ipad",
       "scale" : "1x",
       "size" : "29x29"
     },
     {
+      "filename" : "Icon-App-29x29@2x-1.png",
       "idiom" : "ipad",
       "scale" : "2x",
       "size" : "29x29"
     },
     {
+      "filename" : "Icon-App-40x40@1x-1.png",
       "idiom" : "ipad",
       "scale" : "1x",
       "size" : "40x40"
     },
     {
+      "filename" : "Icon-App-40x40@2x-1.png",
       "idiom" : "ipad",
       "scale" : "2x",
       "size" : "40x40"
     },
     {
+      "filename" : "Icon-App-76x76@1x.png",
       "idiom" : "ipad",
       "scale" : "1x",
       "size" : "76x76"
     },
     {
+      "filename" : "Icon-App-76x76@2x.png",
       "idiom" : "ipad",
       "scale" : "2x",
       "size" : "76x76"
     },
     {
+      "filename" : "Icon-App-83.5x83.5@2x.png",
       "idiom" : "ipad",
       "scale" : "2x",
       "size" : "83.5x83.5"
     },
     {
+      "filename" : "ItunesArtwork@2x.png",
       "idiom" : "ios-marketing",
       "scale" : "1x",
       "size" : "1024x1024"