High CPU use when showing CustomDialogs

[dweymouth]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

Showing a custom confirm dialog using dialog.ShowCustomConfirm uses high CPU while the dialog is displayed. After dismissing the dialog the CPU settles back down to normal.

How to reproduce

Run the example code, with an Activity Monitor/Task Manager/etc window open, and click the button to show the custom confirm dialog

Screenshots

No response

Example code

package main

import (
	"log"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/app"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/dialog"
	"fyne.io/fyne/v2/widget"
)

func main() {
	myApp := app.New()
	myWindow := myApp.NewWindow("Custom Confirm CPU bug")

	button := widget.NewButton("Show dialog", func() {
		dialog.ShowCustomConfirm("Custom confirm", "Confirm text", "Dismiss text",
			widget.NewLabel("Content"), func(b bool) {
				log.Printf("Confirm dismissed with value %v\n", b)
			}, myWindow)
	})
	myWindow.SetContent(container.NewCenter(button))
	myWindow.Resize(fyne.NewSize(400, 300))
	myWindow.ShowAndRun()
}

Fyne version

2.4.3

Go compiler version

go1.21.1

Operating system and version

macOS Ventura M2

Additional Information

No response

[dweymouth]

Reproes with dialog.ShowCustom too

[Jacalz]

Is this specific to custom dialogs or dialogs in general? I can’t think of anything specific that the custom ones do but the others don’t

[dweymouth]

Specific to custom dialogs. Regular ShowInformation, etc don't show the issue. I think it must be somehow related to the CustomDialog type itself

[Jacalz]

It is just a struct with a pointer to the good old dialog struct. Nothing special really. I'm not saying that you are wrong but I have a hard time seeing that it would be specific to custom only

[dweymouth]

Yeah I'm equally confused. Maybe it's a platform-specific thing too. Are you able to replicate it?

[Jacalz]

Just on my phone now, sorry. Can't guarantee when I can have a look

[vinser]

On my Ubuntu SBC your example code with it myWindow.Resize(fyne.NewSize(400, 300)) doesn't make CPU load

But if I stretch main window 1500x600 then it loads CPU high

[vinser]

Loads continuously