Minimizing windows with tables causes a crash

[ckyb]

When using a table, minimizing the imgui window causes a crash with no debug log or stack trace.

Versions

• Godot v4.2.2 via FlatPak on a SteamDeck
• Dear ImGui for Godot v5.1.0 (installed from AssetLib)

Minimal Reproduction

extends Node

var myfloat := [0.0]
var mystr := [""]

func _ready():
    var io := ImGui.GetIO()
    io.ConfigFlags |= ImGui.ConfigFlags_ViewportsEnable

func _process(_delta):
    ImGui.Begin("hello")

    ImGui.BeginTable("Table1", 2)
    ImGui.TableSetupColumn("hello")
    ImGui.TableSetupColumn("world")
    ImGui.TableHeadersRow()

    ImGui.EndTable()

    ImGui.End()

[pkdawson]

I can reproduce the crash, but you should see an error like: ERROR: IM_ASSERT table != NULL && "Need to call TableSetupColumn() after BeginTable()!" (imgui/imgui_tables.cpp:1528)

If you don't, that's a bug. I admit I haven't really tested on Linux at all.

You want to check that BeginTable returns true before adding stuff to the table. Like:

    if ImGui.BeginTable("Table1", 2):
        ImGui.TableSetupColumn("hello")
        ImGui.TableSetupColumn("world")
        ImGui.TableHeadersRow()
        ImGui.EndTable()

See eg, https://github.com/ocornut/imgui/blob/e391fe2e66eb1c96b1624ae8444dc64c23146ef4/imgui_demo.cpp#L621-L636

[ckyb]

I didn't see an error, but that was indeed the cause of the crash - the table needs to be wrapped in an if block to ensure setting up the table can succeed (like your example).

Closing this issue as operator error - thank you for pointing that out!