Support constraintsBlock for showToast method

Example/ViewController.swift

@@ -77,7 +77,7 @@ extension ViewController {
         if section == 0 {
             return 2
         } else {
-            return 11
+            return 12
         }
     }
 
@@ -149,6 +149,7 @@ extension ViewController {
             case 8: cell.textLabel?.text = showingActivity ? "Hide toast activity" : "Show toast activity"
             case 9: cell.textLabel?.text = "Hide toast"
             case 10: cell.textLabel?.text = "Hide all toasts"
+            case 11: cell.textLabel?.text = "Make toast with autolayout"
             default: cell.textLabel?.text = nil
             }
 
@@ -219,8 +220,48 @@ extension ViewController {
         case 10:
             // Hide all toasts
             self.navigationController?.view.hideAllToasts()
+
+        case 11:
+          self.navigationController?.view.showToast(CustomToast(), constraints: { container, toast in
+            toast.translatesAutoresizingMaskIntoConstraints = false
+            toast.leftAnchor.constraint(equalTo: container.leftAnchor, constant: 20).isActive = true
+            toast.rightAnchor.constraint(equalTo: container.rightAnchor, constant: -20).isActive = true
+            toast.bottomAnchor.constraint(equalTo: container.bottomAnchor, constant: -40).isActive = true
+            container.layoutIfNeeded()
+          })
         default:
             break
         }
     }
 }
+
+
+class CustomToast: UIView {
+
+  let titleLabel = {
+    let lb = UILabel()
+    lb.text = "Hello World"
+    return lb
+  }()
+
+  override var intrinsicContentSize: CGSize {
+    return .init(width: UIView.noIntrinsicMetric, height: 60)
+  }
+
+  override init(frame: CGRect) {
+    super.init(frame: frame)
+    self.setup()
+  }
+
+  required init?(coder: NSCoder) {
+    fatalError("init(coder:) has not been implemented")
+  }
+
+  private func setup() {
+    self.backgroundColor = .red
+    self.addSubview(self.titleLabel)
+    self.titleLabel.translatesAutoresizingMaskIntoConstraints = false
+    self.titleLabel.centerXAnchor.constraint(equalTo: self.centerXAnchor).isActive = true
+    self.titleLabel.centerYAnchor.constraint(equalTo: self.centerYAnchor).isActive = true
+  }
+}

Toast/Toast.swift

@@ -28,7 +28,7 @@ import ObjectiveC
 
 /**
  Toast is a Swift extension that adds toast notifications to the `UIView` object class.
- It is intended to be simple, lightweight, and easy to use. Most toast notifications 
+ It is intended to be simple, lightweight, and easy to use. Most toast notifications
  can be triggered with a single line of code.
 
  The `makeToast` methods create a new view and then display it as toast.
@@ -46,6 +46,7 @@ public extension UIView {
         static var duration     = "com.toast-swift.duration"
         static var point        = "com.toast-swift.point"
         static var completion   = "com.toast-swift.completion"
+        static var constraints  = "com.toast-swift.constraints"
         static var activeToasts = "com.toast-swift.activeToasts"
         static var activityView = "com.toast-swift.activityView"
         static var queue        = "com.toast-swift.queue"
@@ -64,6 +65,14 @@ public extension UIView {
         }
     }
 
+    private class ToastConstraintsWrapper {
+      let constraints: ((_ container: UIView, _ toast: UIView) -> Void)?
+
+      init(_ constraints: ((_ container: UIView, _ toast: UIView) -> Void)?) {
+        self.constraints = constraints
+      }
+    }
+
     private enum ToastError: Error {
         case missingParameters
     }
@@ -177,6 +186,31 @@ public extension UIView {
             showToast(toast, duration: duration, point: point)
         }
     }
+
+    /**
+     Displays any view as toast at a provided constraintsBlock and duration. The completion closure
+     executes when the toast view completes. `didTap` will be `true` if the toast view was
+     dismissed from a tap.
+
+     @param toast The view to be displayed as toast
+     @param duration The notification duration
+     @param constarints The constraints block, executed after the toast view added
+     @param completion The completion block, executed after the toast view disappears.
+     didTap will be `true` if the toast view was dismissed from a tap.
+    */
+    func showToast(_ toast: UIView, duration: TimeInterval = ToastManager.shared.duration, constraints: @escaping (_ container: UIView, _ toast: UIView) -> Void, completion: ((_ didTap: Bool) -> Void)? = nil) {
+
+      objc_setAssociatedObject(toast, &ToastKeys.completion, ToastCompletionWrapper(completion), .OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+
+      if ToastManager.shared.isQueueEnabled, activeToasts.count > 0 {
+        objc_setAssociatedObject(toast, &ToastKeys.duration, NSNumber(value: duration), .OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+        objc_setAssociatedObject(toast, &ToastKeys.constraints, ToastConstraintsWrapper(constraints), .OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+
+        queue.add(toast)
+      } else {
+        showToast(toast, duration: duration, constraints: constraints)
+      }
+    }
 
     // MARK: - Hide Toast Methods
 
@@ -334,20 +368,44 @@ public extension UIView {
 
     // MARK: - Private Show/Hide Methods
 
+
+    private func showToast(_ toast: UIView, duration: TimeInterval, constraints: (_ container: UIView, _ toast: UIView) -> Void) {
+      toast.alpha = 0.0
+
+      if ToastManager.shared.isTapToDismissEnabled {
+          let recognizer = UITapGestureRecognizer(target: self, action: #selector(UIView.handleToastTapped(_:)))
+          toast.addGestureRecognizer(recognizer)
+          toast.isUserInteractionEnabled = true
+          toast.isExclusiveTouch = true
+      }
+      activeToasts.add(toast)
+      self.addSubview(toast)
+
+      constraints(self, toast)
+
+      UIView.animate(withDuration: ToastManager.shared.style.fadeDuration, delay: 0.0, options: [.curveEaseOut, .allowUserInteraction], animations: {
+          toast.alpha = 1.0
+      }) { _ in
+          let timer = Timer(timeInterval: duration, target: self, selector: #selector(UIView.toastTimerDidFinish(_:)), userInfo: toast, repeats: false)
+          RunLoop.main.add(timer, forMode: .common)
+          objc_setAssociatedObject(toast, &ToastKeys.timer, timer, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
+      }
+    }
+
     private func showToast(_ toast: UIView, duration: TimeInterval, point: CGPoint) {
         toast.center = point
         toast.alpha = 0.0
-        
+
         if ToastManager.shared.isTapToDismissEnabled {
             let recognizer = UITapGestureRecognizer(target: self, action: #selector(UIView.handleToastTapped(_:)))
             toast.addGestureRecognizer(recognizer)
             toast.isUserInteractionEnabled = true
             toast.isExclusiveTouch = true
         }
-        
+
         activeToasts.add(toast)
         self.addSubview(toast)
-        
+
         UIView.animate(withDuration: ToastManager.shared.style.fadeDuration, delay: 0.0, options: [.curveEaseOut, .allowUserInteraction], animations: {
             toast.alpha = 1.0
         }) { _ in
@@ -375,6 +433,13 @@ public extension UIView {
             if let nextToast = self.queue.firstObject as? UIView, let duration = objc_getAssociatedObject(nextToast, &ToastKeys.duration) as? NSNumber, let point = objc_getAssociatedObject(nextToast, &ToastKeys.point) as? NSValue {
                 self.queue.removeObject(at: 0)
                 self.showToast(nextToast, duration: duration.doubleValue, point: point.cgPointValue)
+                return
+            }
+
+            if let nextToast = self.queue.firstObject as? UIView, let duration = objc_getAssociatedObject(nextToast, &ToastKeys.duration) as? NSNumber, let wrapper = objc_getAssociatedObject(toast, &ToastKeys.constraints) as? ToastConstraintsWrapper, let constraints = wrapper.constraints {
+                self.queue.removeObject(at: 0)
+                self.showToast(nextToast, duration: duration.doubleValue, constraints: constraints)
+                return
             }
         }
     }