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Common Issues

When using Iris you may run into different issues. The most common ones are explained below and explain why the issue arises and how to fix it.

Iris.Init() can only be called once.​

Error

Iris.Init() can only be called once.

Iris can only be initialised once per client. The best way to initialise Iris then is to place it at the start of one of your first running script. For example you may have:

----------------------------------
--- ReplicatedFirst/client.lua or StarterPlayer/StarterPlayerScripts/client.lua
----------------------------------
 1| -- code in ReplicatedFirst will execute before other code, so it is best practice 
 2| -- to initialise Iris here even if you are not going to use it.
 3| reqire(game.ReplicatedStorage.Iris).Init()
 4| 
 5| ...

----------------------------------------
--- StarterPlayer/StarterPlayerScripts/raycast.lua
----------------------------------------
 1| -- therefore, when you require it any scripts elsewhere it is already initialised
 2| -- and ready to go and you do not need to worry about where to init
 3| local Iris = require(game.ReplicatedStorage.Iris)
 4| 
 5| -- wrong, you have initialised it twice here
 6| local Iris = require(game.ReplicatedStorage.Iris).Init()
 7|
 8| ...

This becomes more difficult if you have many local scripts which could all execute at the same time. This is why most games will only use a few local scripts and rely on modules for the rest, which ensures that code runs in an expected and deterministic order and therefore any client-wide initialisation can happen before anything that relies on it does.

Iris:Connect() was called before calling Iris.Init(); always initialise Iris first.​

Warn

Iris:Connect() was called before calling Iris.Init(); always initialise Iris first.

Iris should always be initialised before attempting to use 'Connect()'. This is just a warning to make sure that you are initialising Iris in the first place. If you connect and then initialise, your code will still run normally and Iris functions fine. However, as mentioned in the Iris.Init() can only be called once. issue, it is better practice to initalise Iris before any other Iris code runs and therefore you can ensure consistent ordering.

Iris cycleCoroutine took to long to yield. Connected functions should not yield.​

Error

Iris cycleCoroutine took to long to yield. Connected functions should not yield.

Iris does not support yielding statements becaues it needs to run and finish every frame. Therefore if you have code which needs to yield and wait, you should either handle it outside of an Iris widget, or spawn a new thread. The example below demonstrates the issue:

-----------------------
--- bad_example.lua
-----------------------
 4| Iris.Window({"Async Window"})
 5|     -- this code yeilds which will prevent Iris from finishing before the next frame
 6|     local response = httpService:GetAsync(...)
 7|     Iris.Text(response)
 8| Iris.End()

------------------------
--- good_example.lua    
------------------------
 4| local response = "NONE"
 5| 
 6| Iris.Window({"Async Window"})
 7|     -- we use another thread to ensure the thread Iris is in will finish before the next frame
 8|     task.spawn(function()
 9|         response = httpService:GetAsync(...)
10|     end)
11|     Iris.Text(response)
12| Iris.End()

These examples are fairly simple, but when you are integrating Iris directly into your codebase it should become much clearer.

Too few calls to Iris.End()., Too many calls to Iris.End().​

Error

Too few calls to Iris.End()., Too many calls to Iris.End().

These issues are caused respectively by have too few or too many calls to Iris.End(). Every widget that has children, from Windows and Trees to MenuBars and Combos to SameLine and Indent must have an Iris.End() statement to say that you are done appending to that parent. To ensure this does not happen, it is best to use do-end blocks to indent out parent widgets from their children and make it clearer to see where an Iris.End() statement must go. For example:

 4| Iris.Window({ "Do-End Block" })
 5| do
 6|     Iris.Text({ "Text goes here." })
 7| end
 8| Iris.End()

This makes it clear that an Iris.End() statement should always go after an end block.

This issue may also arise if some of your code either yields or errors and therefore not all the Iris.End() calls happen. For example:

 4| Iris.Window({ "Valid Code with Error" })
 5|     error("Something has gone wrong. :(") -- errors within Iris
 6| Iris.End()

 7| Iris.Window({ "Asynchronous Code" })
 8|     task.wait(1) -- yeilds within Iris
 9| Iris.End()

Although all the Iris.End() statements are there and in the right space, the error has prevented it from running and therefore we will get this error.