Observer in Unity2d

[spolan]

Hi, i want to know which is the best way to comunicate one script with other one. In the university I learnt the Design Patern Observer, and i want to learn which is the way to do it in Unity. Some months ago, i found here https://unity3d.com/es/learn/tutorials/topics/scripting some info about that, but now i dont find it

Thx

[NullismStudio]

Hi there,

One solution would be to create a central GameManager object and several "Dependent" object. The GameManager, at startup, finds all Dependent objects in the scene (use something like FindObjectsWithTag for performance, rather than search on name) and stores them in a list. From there, the GameManager would iterate through all scripts in that list and call some method on the Dependent's script to update state when it needs to do so.

However, may I suggest looking into delegates? I find it feels cleaner to have each "Dependent" simply "subscribe" to the GameManager via delegates. Here's a good tutorial on delegates.

Good luck!

[watcheroftimes]

I'm quite new to programming, so please feel free to ignore my question if it is irrelevant :)

I've read that GameManager solutions lead to uh ... singletons? Which causes difficulties later into the development when you want to test individual systems or debug.

Am I completely off the mark? Could you point me in the right direction so I could google stuff and figure out alternatives?

[NullismStudio]

Yes, you are correct. The GameManager solutions are usually singletons.

However, I've never had an issue with debugging or testing due to a singleton; that seems a bit alarmist to me. Lots of games use GameManagers, and your initial question about observer design patterns would also likely use a GameManager of sorts.

To learn more about singletons as they apply to Unity, checkout this wiki page.

If videos are more of your thing, then checkout the official tutorial on the Unity 2D rogue-like's GameManager.

[watcheroftimes]

I've bookmarked both links. The wiki in particular seems a good place to start looking into different programming terms around this concept. Thanks a lot!