From f756d077db9a2bb2009a4595e94169501bb2263f Mon Sep 17 00:00:00 2001
From: Lukas Weber <luweber@microsoft.com>
Date: Fri, 22 May 2020 13:27:51 +0200
Subject: [PATCH] fix: trigger activate event when app is activated via app
 switcher

When application is activated thru macOS app switcher (cmd+tab) the
App's activate event is note emitted. The reason is that
`applicationShouldHandleReopen:hasVisibleWindows:` is sent only when app
is activated via Dock. Using `applicationDidBecomeActive:` is handling
all cases properly.
---
 .../mac/electron_application_delegate.mm      | 39 ++++++++++++++++---
 1 file changed, 34 insertions(+), 5 deletions(-)

diff --git a/shell/browser/mac/electron_application_delegate.mm b/shell/browser/mac/electron_application_delegate.mm
index f5da4f4febfba..635480bc20c21 100644
--- a/shell/browser/mac/electron_application_delegate.mm
+++ b/shell/browser/mac/electron_application_delegate.mm
@@ -41,7 +41,10 @@ - (void)_coreAttributesFromRange:(NSRange)range
 @end
 #endif  // BUILDFLAG(USE_ALLOCATOR_SHIM)
 
-@implementation ElectronApplicationDelegate
+@implementation ElectronApplicationDelegate {
+ @private
+  bool isFirstActivation_;
+}
 
 - (void)setApplicationDockMenu:(electron::ElectronMenuModel*)model {
   menu_controller_.reset([[ElectronMenuController alloc] initWithModel:model
@@ -78,6 +81,8 @@ - (void)applicationDidFinishLaunching:(NSNotification*)notify {
         @selector(_coreAttributesFromRange:whichAttributes:completionHandler:));
   }
 #endif
+
+  isFirstActivation_ = true;
 }
 
 - (NSMenu*)applicationDockMenu:(NSApplication*)sender {
@@ -92,11 +97,35 @@ - (BOOL)application:(NSApplication*)sender openFile:(NSString*)filename {
   return electron::Browser::Get()->OpenFile(filename_str) ? YES : NO;
 }
 
-- (BOOL)applicationShouldHandleReopen:(NSApplication*)theApplication
-                    hasVisibleWindows:(BOOL)flag {
+- (void)applicationDidBecomeActive:(NSNotification*)notify {
+  // Originally `applicationShouldHandleReopen:hasVisibleWindows:` was used to
+  // emit Activate event. But the message is sent only when application is
+  // activated via Dock or Finder ignoring the App Switcher (cmd+tab).
+  //
+  // Using `applicationDidBecomeActive' is more reliable but to maintain
+  // compatibility with previous implementation we ignore activation
+  // immediately after the application launch, and compute the
+  // hasVisibleWindows on our own.
+  //
+  // Details in https://github.com/electron/electron/pull/23727.
+
+  if (isFirstActivation_) {
+    isFirstActivation_ = false;
+    return;
+  }
+
+  NSApplication* app = notify.object;
+  bool hasVisibleWindows = false;
+
+  for (NSWindow* win in app.windows) {
+    if (win.isVisible || win.miniaturized) {
+      hasVisibleWindows = true;
+      break;
+    }
+  }
+
   electron::Browser* browser = electron::Browser::Get();
-  browser->Activate(static_cast<bool>(flag));
-  return flag;
+  browser->Activate(hasVisibleWindows);
 }
 
 - (BOOL)application:(NSApplication*)sender