Fixed Navigation Bar disappearing on zooming in and out.

Signal/src/ViewControllers/MediaGallery/MediaItemViewController.swift

@@ -1,4 +1,4 @@
 //
 // Copyright 2023 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 //
@@ -9,9 +9,9 @@
 import YYImage
 
 protocol MediaItemViewControllerDelegate: AnyObject {
-
     func mediaItemViewControllerDidTapMedia(_ viewController: MediaItemViewController)
     func mediaItemViewControllerWillBeginZooming(_ viewController: MediaItemViewController)
+    func mediaItemViewControllerFullyZoomedOut(_ viewController: MediaItemViewController)
 }
 
 protocol VideoPlaybackStatusProvider: AnyObject {
@@ -403,6 +403,13 @@
         delegate?.mediaItemViewControllerWillBeginZooming(self)
     }
 
+    //This is called at the end of whenever we zoom in, or zoom out. "Zooming" in this context means both zooming in and out.
+    func scrollViewDidEndZooming(_ scrollView: UIScrollView, with view: UIView?, atScale scale: CGFloat) {
+        if scale <= scrollView.minimumZoomScale {
+            delegate?.mediaItemViewControllerFullyZoomedOut(self)
+        }
+    }
+
     func scrollViewDidZoom(_ scrollView: UIScrollView) {
         updateZoomScaleAndConstraints()
         view.layoutIfNeeded()

Signal/src/ViewControllers/MediaGallery/MediaPageViewController.swift

@@ -1,4 +1,4 @@
 //
 // Copyright 2018 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 //
@@ -725,14 +725,18 @@
 }
 
 extension MediaPageViewController: MediaItemViewControllerDelegate {
-
+    
     func mediaItemViewControllerDidTapMedia(_ viewController: MediaItemViewController) {
         setShouldHideToolbars(!shouldHideToolbars, animated: true)
     }
 
     func mediaItemViewControllerWillBeginZooming(_ viewController: MediaItemViewController) {
         setShouldHideToolbars(true, animated: true)
     }
+
+    func mediaItemViewControllerFullyZoomedOut(_ viewController: MediaItemViewController) {
+        setShouldHideToolbars(false, animated: true)
+    }
 }
 
 extension MediaGalleryItem: GalleryRailItem {