🐛 Close #15 with vide coding (not tested)

linux/my_application.cc

@@ -102,6 +102,6 @@ static void my_application_init(MyApplication* self) {}
 MyApplication* my_application_new() {
   return MY_APPLICATION(g_object_new(my_application_get_type(),
                                      "application-id", APPLICATION_ID,
-                                     "flags", G_APPLICATION_NON_UNIQUE,
+                                     "flags", G_APPLICATION_FLAGS_NONE,
                                      nullptr));
 }

windows/runner/main.cpp

@@ -8,8 +8,29 @@ auto bdw = bitsdojo_window_configure(BDW_CUSTOM_FRAME | BDW_HIDE_ON_STARTUP);
 #include "flutter_window.h"
 #include "utils.h"
 
+HANDLE g_hMutex = NULL;
+
+bool CheckIfAlreadyRunning() {
+    g_hMutex = CreateMutex(NULL, FALSE, L"Global\\SolianDesktop");
+
+    if (g_hMutex == NULL) {
+        return true; // Mutex creation failed
+    }
+
+    if (GetLastError() == ERROR_ALREADY_EXISTS) {
+        CloseHandle(g_hMutex);
+        return true; // Another instance is running
+    }
+
+    return false;
+}
+
 int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
                       _In_ wchar_t *command_line, _In_ int show_command) {
+  if (CheckIfAlreadyRunning()) {
+    return EXIT_SUCCESS;
+  }
+
   // Attach to console when present (e.g., 'flutter run') or create a
   // new console when running with a debugger.
   if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent()) {