sokol_app.h macos: replaced workaround for 'no key-up during Cmd

pressed' replaced with proper fix.

macOS doesn't send key-up events while Cmd is down for whatever
reasons (both native and in browsers). This change fixes at least
the native side by installing an event monitor callback function.

Special thanks to GLFW for providing a solution.

No such fix possible for Emscripten unfortunately.

1 files changed, 17 insertions, 7 deletions

diff --git a/sokol_app.h b/sokol_app.h
index 880ef902..64e90bc3 100644
--- a/sokol_app.h
+++ b/sokol_app.h
@@ -2300,6 +2300,7 @@ typedef struct {
     uint8_t mouse_buttons;
     NSWindow* window;
     NSTrackingArea* tracking_area;
+    id keyup_monitor;
     _sapp_macos_app_delegate* app_dlg;
     _sapp_macos_window_delegate* win_dlg;
     _sapp_macos_view* view;
@@ -3403,6 +3404,11 @@ _SOKOL_PRIVATE void _sapp_macos_init_keytable(void) {
 
 _SOKOL_PRIVATE void _sapp_macos_discard_state(void) {
     // NOTE: it's safe to call [release] on a nil object
+    if (_sapp.macos.keyup_monitor != nil) {
+        [NSEvent removeMonitor:_sapp.macos.keyup_monitor];
+        // NOTE: removeMonitor also releases the object
+        _sapp.macos.keyup_monitor = nil;
+    }
     _SAPP_OBJC_RELEASE(_sapp.macos.tracking_area);
     _SAPP_OBJC_RELEASE(_sapp.macos.app_dlg);
     _SAPP_OBJC_RELEASE(_sapp.macos.win_dlg);
@@ -3439,11 +3445,22 @@ _SOKOL_PRIVATE void _sapp_macos_run(const sapp_desc* desc) {
     _sapp_init_state(desc);
     _sapp_macos_init_keytable();
     [NSApplication sharedApplication];
+
     // set the application dock icon as early as possible, otherwise
     // the dummy icon will be visible for a short time
     sapp_set_icon(&_sapp.desc.icon);
     _sapp.macos.app_dlg = [[_sapp_macos_app_delegate alloc] init];
     NSApp.delegate = _sapp.macos.app_dlg;
+
+    // workaround for "no key-up sent while Cmd is pressed" taken from GLFW:
+    NSEvent* (^keyup_monitor)(NSEvent*) = ^NSEvent* (NSEvent* event) {
+        if ([event modifierFlags] & NSEventModifierFlagCommand) {
+            [[NSApp keyWindow] sendEvent:event];
+        }
+        return event;
+    };
+    _sapp.macos.keyup_monitor = [NSEvent addLocalMonitorForEventsMatchingMask:NSEventMaskKeyUp handler:keyup_monitor];
+
     [NSApp run];
     // NOTE: [NSApp run] never returns, instead cleanup code
     // must be put into applicationWillTerminate
@@ -4178,15 +4195,8 @@ _SOKOL_PRIVATE void _sapp_macos_poll_input_events() {
 - (void)keyDown:(NSEvent*)event {
     if (_sapp_events_enabled()) {
         const uint32_t mods = _sapp_macos_mods(event);
-        /* NOTE: macOS doesn't send keyUp events while the Cmd key is pressed,
-            as a workaround, to prevent key presses from sticking we'll send
-            a keyup event following right after the keydown if SUPER is also pressed
-        */
         const sapp_keycode key_code = _sapp_translate_key(event.keyCode);
         _sapp_macos_key_event(SAPP_EVENTTYPE_KEY_DOWN, key_code, event.isARepeat, mods);
-        if (0 != (mods & SAPP_MODIFIER_SUPER)) {
-            _sapp_macos_key_event(SAPP_EVENTTYPE_KEY_UP, key_code, event.isARepeat, mods);
-        }
         const NSString* chars = event.characters;
         const NSUInteger len = chars.length;
         if (len > 0) {