Handling Invalid Window IDs

What happens if I pass an invalid windowID to SDL_GetWindowFromID()?

If you pass an invalid windowID to SDL_GetWindowFromID(), the function will return nullptr. SDL uses nullptr to indicate that no window exists with the given ID.

Common Scenarios for Invalid IDs

  • A window was destroyed, and its ID is no longer valid.
  • You accidentally passed an uninitialized or incorrect ID.
  • Bugs in your program caused the wrong ID to be stored or retrieved.

Here's an example:

// Invalid ID
SDL_Window* window = SDL_GetWindowFromID(9999);
if (!window) {
  std::cerr << "Error: Invalid window ID\n";
}

Best Practices

  • Always check for nullptr after calling SDL_GetWindowFromID().
  • Use SDL_DestroyWindow() cautiously to avoid dangling references.
  • Log or debug IDs to ensure they are correct.

By handling invalid IDs gracefully, you can avoid crashes and improve the robustness of your application.

Window Events and Window IDs

Discover how to monitor and respond to window state changes in SDL applications

Questions & Answers

Answers are generated by AI models and may not have been reviewed. Be mindful when running any code on your device.

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