From b5079791973ba36313e0beb2ebb00705e7547a87 Mon Sep 17 00:00:00 2001
From: Fernando Bunn <bunn@idevzilla.com>
Date: Wed, 18 Dec 2024 16:00:57 -0300
Subject: [PATCH] Fix alpha animation

---
 ...undedPageSheetContainerViewController.swift | 18 +++++++++++++++++-
 .../RoundedPageSheetPresentationAnimator.swift |  6 ++++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/DuckDuckGo/RoundedPageContainer/RoundedPageSheetContainerViewController.swift b/DuckDuckGo/RoundedPageContainer/RoundedPageSheetContainerViewController.swift
index fdceff2c95..3ce8888906 100644
--- a/DuckDuckGo/RoundedPageContainer/RoundedPageSheetContainerViewController.swift
+++ b/DuckDuckGo/RoundedPageContainer/RoundedPageSheetContainerViewController.swift
@@ -22,6 +22,7 @@ import UIKit
 final class RoundedPageSheetContainerViewController: UIViewController {
     let contentViewController: UIViewController
     private let allowedOrientation: UIInterfaceOrientationMask
+    let backgroundView = UIView()
 
     private var interactiveDismissalTransition: UIPercentDrivenInteractiveTransition?
     private var isInteractiveDismissal = false
@@ -52,8 +53,9 @@ final class RoundedPageSheetContainerViewController: UIViewController {
 
     override func viewDidLoad() {
         super.viewDidLoad()
-        view.backgroundColor = .black
+        view.backgroundColor = .clear
 
+        setupBackgroundView()
         setupContentViewController()
     }
 
@@ -86,6 +88,20 @@ final class RoundedPageSheetContainerViewController: UIViewController {
         }
     }
 
+    private func setupBackgroundView() {
+        view.addSubview(backgroundView)
+
+        backgroundView.backgroundColor = .black
+        backgroundView.translatesAutoresizingMaskIntoConstraints = false
+
+        NSLayoutConstraint.activate([
+            backgroundView.topAnchor.constraint(equalTo: view.topAnchor),
+            backgroundView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
+            backgroundView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
+            backgroundView.trailingAnchor.constraint(equalTo: view.trailingAnchor)
+        ])
+    }
+
     private func setupContentViewController() {
         addChild(contentViewController)
         view.addSubview(contentViewController.view)
diff --git a/DuckDuckGo/RoundedPageContainer/RoundedPageSheetPresentationAnimator.swift b/DuckDuckGo/RoundedPageContainer/RoundedPageSheetPresentationAnimator.swift
index f86aab1bcd..85cd7d8787 100644
--- a/DuckDuckGo/RoundedPageContainer/RoundedPageSheetPresentationAnimator.swift
+++ b/DuckDuckGo/RoundedPageContainer/RoundedPageSheetPresentationAnimator.swift
@@ -66,6 +66,7 @@ class RoundedPageSheetDismissalAnimator: NSObject, UIViewControllerAnimatedTrans
               let fromView = fromViewController.view,
               let contentView = fromViewController.contentViewController.view else { return }
 
+        let fromBackgroundView = fromViewController.backgroundView
         let containerView = transitionContext.containerView
 
         UIView.animate(withDuration: AnimatorConstants.duration,
@@ -74,7 +75,7 @@ class RoundedPageSheetDismissalAnimator: NSObject, UIViewControllerAnimatedTrans
                        initialSpringVelocity: AnimatorConstants.springVelocity,
                        options: .curveEaseInOut,
                        animations: {
-            fromView.alpha = 0
+            fromBackgroundView.alpha = 0
             contentView.transform = CGAffineTransform(translationX: 0, y: containerView.bounds.height)
         }, completion: { finished in
             fromView.removeFromSuperview()
@@ -94,10 +95,11 @@ class RoundedPageSheetDismissalAnimator: NSObject, UIViewControllerAnimatedTrans
         }
 
         let containerView = transitionContext.containerView
+        let fromBackgroundView = fromViewController.backgroundView
 
         let animator = UIViewPropertyAnimator(duration: AnimatorConstants.duration,
                                               dampingRatio: AnimatorConstants.springDamping) {
-            fromView.alpha = 0
+            fromBackgroundView.alpha = 0
             contentView.transform = CGAffineTransform(translationX: 0, y: containerView.bounds.height)
         }