Button/toolbar weird flickering inside table

[UrbiJr]

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

When putting either a *widget.Toolbar or a *widget.Button inside a *widget.Table cell, it makes a weird flickering whenever you put the cursor on that cell.
Putting the cursor in a certain position will also cause different effects depending on the position: the toolbar for example would display its icons partially if putting the cursor above the first icon, instead putting it above the last (third) icon always displays the toolbar correctly.

How to reproduce

• Create a widget.Table using widget.NewTable
• Inside the update func(TableCellID, fyne.CanvasObject) body, put the code to insert either a *widget.Toolbar or a *widget.Button in a cell
• Display the table and run the program

Screenshots

Example code

func (app *Config) getProfilesTable() *widget.Table {
	t := widget.NewTable(
		func() (int, int) {
			return len(app.ProfilesSlice), len(app.ProfilesSlice[0])
		},
		func() fyne.CanvasObject {
			ctr := container.NewVBox(widget.NewLabel(""))
			ctr.Resize(fyne.Size{Height: 50})
			return ctr
		},
		func(tci widget.TableCellID, co fyne.CanvasObject) {
			// in order: if last column && not the first row
			if tci.Col == (len(app.ProfilesSlice[0])-1) && tci.Row != 0 {
				w := widget.NewToolbar(
					widget.NewToolbarAction(theme.ContentCopyIcon(), func() {}),
					widget.NewToolbarAction(theme.DocumentCreateIcon(), func() {}),
					widget.NewToolbarAction(theme.DeleteIcon(), func() {}))

				co.(*fyne.Container).Objects = []fyne.CanvasObject{w}
			} else {
				// we're just putting in textual information
				co.(*fyne.Container).Objects = []fyne.CanvasObject{
					widget.NewLabel(app.ProfilesSlice[tci.Row][tci.Col].(string)),
				}
			}
		})

	colWidths := []float32{100, 200, 200, 200, 60}
	for i, w := range colWidths {
		t.SetColumnWidth(i, w)
	}

	for i := 1; i < len(app.ProfilesSlice); i++ {
		t.SetRowHeight(i, 55)
	}

	return t
}

Fyne version

2.3.1

Go compiler version

go1.19.1 windows/amd64 / go1.19.1 darwin/arm64

Operating system and version

Windows 11 / macOS Monterey

Additional Information

I would like to add, I'm extremely grateful for your work! Fyne is really extraordinary and I can't wait to finish my application. Thank you!

[andydotxyz]

Do not create new content in the Update callback - this is where you should configure components that were created in the Create callback.
You can hide and show but creating new items will not give the desired result.

[junmaqiang]

Do not create new content in the Update callback - this is where you should configure components that were created in the Create callback. You can hide and show but creating new items will not give the desired result.

I think Official lack of trial examples to guide

[andydotxyz]

What I described is documented at https://developer.fyne.io/widget/table

[UrbiJr]

hey there, sorry if I hadn't replied sooner, but just got busy with other work.
I solved looking at the example @andydotxyz mentioned, and also thanks to a SO question.

If anyone needs, this is how I put a toolbar and other objects inside a table (not it won't flicker anymore 😁):

package main

import (
	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/app"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/theme"
	"fyne.io/fyne/v2/widget"
)

var data = [][]string{[]string{"label", "actions"},
	[]string{"hello", "toolbar goes here"}}

func main() {
	myApp := app.New()
	myWindow := myApp.NewWindow("Table Widget")

	list := widget.NewTable(
		func() (int, int) {
			return len(data), len(data[0])
		},
		func() fyne.CanvasObject {
			lbl := widget.NewLabel("")
			toolbar := widget.NewToolbar()
			toolbar.Hide()
			return container.NewMax(lbl, toolbar)
		},
		func(i widget.TableCellID, o fyne.CanvasObject) {
			container := o.(*fyne.Container)
			lbl := container.Objects[0].(*widget.Label)
			toolbar := container.Objects[1].(*widget.Toolbar)

			if i.Row != 0 && i.Col == 1 {
				lbl.Hide()
				toolbar.Hidden = false

				if len(toolbar.Items) == 0 {
					toolbar.Append(widget.NewToolbarAction(theme.ContentCopyIcon(), func() {}))
					toolbar.Append(widget.NewToolbarAction(theme.DocumentCreateIcon(), func() {}))
					toolbar.Append(widget.NewToolbarAction(theme.DeleteIcon(), func() {}))
				}

			} else {
				toolbar.Hide()
				lbl.Hidden = false
				lbl.SetText(data[i.Row][i.Col])
			}
		})

	// hide first column (ID)
	colWidths := []float32{100, 100}
	for i, w := range colWidths {
		list.SetColumnWidth(i, w)
	}

	myWindow.SetContent(list)
	myWindow.ShowAndRun()
}