Fixes Mac Catalyst: random crash inside [_UIBlurEffectCoreUIImpl _needsUpdateForTransitionFromEnvironment:toEnvironment:usage:] ()

PSPDFCatalystPatches.m

Use this code: (code incomplete, but you get the idea what needs to be done)


// TODO: Stop calling this once 10.15.1 is out!
#if TARGET_OS_UIKITFORMAC
static void PSPDFFixVisualEffectsEnvironment(void) {
    static const char *PSPDFVisualEffectsWindowKey;
    static const char *PSPDFVisualEffectsSuperviewKey;
    let klass = NSClassFromString([NSString stringWithFormat:@"_%@sualEffe%@ironment", @"UIVi", @"ctEnv"]);

    pspdf_swizzleSelectorWithBlock(klass, @selector(setWindow:), ^(NSObject *_self, UIWindow *window) {
        [_self pspdf_setWeakAssociatedObject:window forKey:&PSPDFVisualEffectsWindowKey];
    });
    pspdf_swizzleSelectorWithBlock(klass, @selector(window), ^(NSObject *_self) {
        return [_self pspdf_weakAssociatedObjectForKey:&PSPDFVisualEffectsWindowKey];
    });

    pspdf_swizzleSelectorWithBlock(klass, NSSelectorFromString([NSString stringWithFormat:@"set%@view:", @"Super"]), ^(NSObject *_self, UIView *superview) {
        [_self pspdf_setWeakAssociatedObject:superview forKey:&PSPDFVisualEffectsSuperviewKey];
    });
    pspdf_swizzleSelectorWithBlock(klass, @selector(superview), ^(NSObject *_self) {
        return [_self pspdf_weakAssociatedObjectForKey:&PSPDFVisualEffectsSuperviewKey];
    });
}
#endif


If you see following crash:

lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x20)
    frame #0: 0x00007fff6cd0d708 libobjc.A.dylib`objc_retain + 24
    frame #1: 0x000000010fd7a8fe UIKitCore`-[_UIBlurEffectCoreUIImpl _needsUpdateForTransitionFromEnvironment:toEnvironment:usage:] + 275
    frame #2: 0x000000010f1667ed UIKitCore`-[UIBlurEffect _needsUpdateForTransitionFromEnvironment:toEnvironment:usage:] + 65
    frame #3: 0x000000010f17fe29 UIKitCore`-[UIVisualEffectView _updateEnvironmentAndFlagUpdatesIfNecessary:] + 312
    frame #4: 0x000000010f180142 UIKitCore`-[UIVisualEffectView _updateEffectForAppearsKeyChanges:] + 221
    frame #5: 0x00007fff3f9fa18f CoreFoundation`__CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 12
    frame #6: 0x00007fff3fa8aa63 CoreFoundation`___CFXRegistrationPost1_block_invoke + 63
    frame #7: 0x00007fff3fa8a0f8 CoreFoundation`_CFXRegistrationPost1 + 372
    frame #8: 0x00007fff3fa027de CoreFoundation`___CFXNotificationPost_block_invoke + 97
    frame #9: 0x00007fff3f96aaf2 CoreFoundation`-[_CFXNotificationRegistrar find:object:observer:enumerator:] + 1575
    frame #10: 0x00007fff3f969f82 CoreFoundation`_CFXNotificationPost + 1351
    frame #11: 0x00007fff41fde92b Foundation`-[NSNotificationCenter postNotificationName:object:userInfo:] + 59
    frame #12: 0x00000001111d036b UIKitMacHelper`-[UINSWindow _postWindowNotificationName:] + 89
    frame #13: 0x00007fff42031975 Foundation`__NSFireDelayedPerform + 415
    frame #14: 0x00007fff3f9b75b4 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
    frame #15: 0x00007fff3f9b716e CoreFoundation`__CFRunLoopDoTimer + 859
    frame #16: 0x00007fff3f9b6b8e CoreFoundation`__CFRunLoopDoTimers + 317
    frame #17: 0x00007fff3f99793d CoreFoundation`__CFRunLoopRun + 2213
    frame #18: 0x00007fff3f996e13 CoreFoundation`CFRunLoopRunSpecific + 499
    frame #19: 0x00007fff3e63eb2d HIToolbox`RunCurrentEventLoopInMode + 292
    frame #20: 0x00007fff3e63e86d HIToolbox`ReceiveNextEventCommon + 600
    frame #21: 0x00007fff3e63e5f7 HIToolbox`_BlockUntilNextEventMatchingListInModeWithFilter + 64
    frame #22: 0x00007fff3cef1d74 AppKit`_DPSNextEvent + 990
    frame #23: 0x00007fff3cef0ae4 AppKit`-[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 1352
    frame #24: 0x00007fff3ceeb284 AppKit`-[NSApplication run] + 658
    frame #25: 0x00007fff3cedd12d AppKit`NSApplicationMain + 777
    frame #26: 0x00007fff3d35e544 AppKit`_NSApplicationMainWithInfoDictionary + 16
    frame #27: 0x000000011119442c UIKitMacHelper`UINSApplicationMain + 322
    frame #28: 0x000000010ee95f94 UIKitCore`UIApplicationMain + 2206
  * frame #29: 0x000000010010ed39 Viewer`main at main.swift:12:1
    frame #30: 0x00007fff6e06b405 libdyld.dylib`start + 1
    frame #31: 0x00007fff6e06b405 libdyld.dylib`start + 1
(lldb)