From b2dcdc02c77089d867d08667e3fb39ce60b9ce45 Mon Sep 17 00:00:00 2001
From: Riley Testut <riley@rileytestut.com>
Date: Tue, 4 Apr 2023 17:06:58 -0500
Subject: [PATCH] Dynamically disables interactive back gesture when viewing
 source header image

Only disables gesture if touches are within headerContainerView to ensure back gesture works as expected majority of the time.
---
 .../HeaderContentViewController.swift         | 24 ++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/AltStore/Components/HeaderContentViewController.swift b/AltStore/Components/HeaderContentViewController.swift
index 3b8de9d5..c4da27c6 100644
--- a/AltStore/Components/HeaderContentViewController.swift
+++ b/AltStore/Components/HeaderContentViewController.swift
@@ -20,7 +20,8 @@ protocol ScrollableContentViewController: UIViewController
 
 class HeaderContentViewController<Header: UIView, Content: ScrollableContentViewController> : UIViewController,
                                                                                               UIAdaptivePresentationControllerDelegate,
-                                                                                              UIScrollViewDelegate
+                                                                                              UIScrollViewDelegate,
+                                                                                              UIGestureRecognizerDelegate
 {
     var tintColor: UIColor? {
         didSet {
@@ -48,6 +49,8 @@ class HeaderContentViewController<Header: UIView, Content: ScrollableContentView
     private var backgroundBlurView: UIVisualEffectView!
     private var contentViewControllerShadowView: UIView!
     
+    private var ignoreBackGestureRecognizer: UIPanGestureRecognizer!
+    
     private var blurAnimator: UIViewPropertyAnimator?
     private var navigationBarAnimator: UIViewPropertyAnimator?
     private var contentSizeObservation: NSKeyValueObservation?
@@ -117,6 +120,11 @@ class HeaderContentViewController<Header: UIView, Content: ScrollableContentView
         self.headerContainerView = UIView(frame: .zero)
         self.view.addSubview(self.headerContainerView, pinningEdgesWith: .zero)
         
+        self.ignoreBackGestureRecognizer = UIPanGestureRecognizer(target: self, action: nil)
+        self.ignoreBackGestureRecognizer.delegate = self
+        self.headerContainerView.addGestureRecognizer(self.ignoreBackGestureRecognizer)
+        self.navigationController?.interactivePopGestureRecognizer?.require(toFail: self.ignoreBackGestureRecognizer) // So we can disable back gesture when viewing header.
+        
         self.headerScrollView = UIScrollView(frame: .zero)
         self.headerScrollView.delegate = self
         self.headerScrollView.isPagingEnabled = true
@@ -420,6 +428,20 @@ class HeaderContentViewController<Header: UIView, Content: ScrollableContentView
         default: break
         }
     }
+    
+    //MARK: UIGestureRecognizerDelegate
+    
+    func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool
+    {
+        // Ignore interactive back gesture when viewing header, which means returning `true` to enable ignoreBackGestureRecognizer.
+        let disableBackGesture = self.isViewingHeader
+        return disableBackGesture
+    }
+    
+    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool
+    {
+        return true
+    }
 }
 
 private extension HeaderContentViewController