Add Option to CheckGroup to make Rows/Columns

[BieHDC]

Description:

This adds an option to CheckGroup to make Rows/Columns instead of one long list.
I made this for a program i am currently writing and it makes sense to upstream.
It is fully backwards compatible.

Video:
https://github.com/user-attachments/assets/79bf6be3-0d93-4e51-8f94-f94c1244da75

Example Code for testing:

package main

import (
	"fmt"
	"strconv"

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

type gui struct {
	a fyne.App
	w fyne.Window
}

func main() {
	g := gui{}

	g.a = app.NewWithID("biehdc.fynedev.checkgroupcolumns")
	g.w = g.a.NewWindow("CheckGroup with Rows/Columns")
	g.w.CenterOnScreen()
	g.w.Resize(fyne.NewSize(800, 600))

	g.w.SetContent(g.content())
	g.w.ShowAndRun()
}

func (g *gui) content() fyne.CanvasObject {
	contenttainer := container.NewStack()
	setcontentainer := func(co fyne.CanvasObject) {
		contenttainer.Objects = []fyne.CanvasObject{co}
		contenttainer.Refresh()
	}

	numitems := widget.NewEntry()
	numitems.PlaceHolder = "Amount of items to generate"
	numcols := widget.NewEntry()
	numcols.PlaceHolder = "Amount of Rows/Columns"
	togglehorizonal := widget.NewCheck("Horizontal", nil)
	makeui := widget.NewButton("Make Example", func() {
		ni, err := strconv.Atoi(numitems.Text)
		if err != nil {
			dialog.ShowError(err, g.w)
			return
		}

		nr, err := strconv.Atoi(numcols.Text)
		if err != nil {
			dialog.ShowError(err, g.w)
			return
		}

		var items []string
		for i := range ni {
			items = append(items, fmt.Sprintf("Check Item %d", i))
		}

		checkgroup := widget.NewCheckGroup(items, nil)
		checkgroup.SetColumns(nr)
		checkgroup.Horizontal = togglehorizonal.Checked

		setcontentainer(checkgroup)
	})
	numitems.OnSubmitted = func(_ string) { makeui.OnTapped() }
	numcols.OnSubmitted = func(_ string) { makeui.OnTapped() }

	return container.NewBorder(
		container.NewHBox(
			NewMinSizer(numitems, fyne.NewSize(300, 0)),
			NewMinSizer(numcols, fyne.NewSize(300, 0)),
			togglehorizonal, makeui,
		), nil, nil, nil,
		container.NewScroll(contenttainer),
	)
}

type minSizer struct {
	widget.BaseWidget
	child   fyne.CanvasObject
	minsize fyne.Size
}

func NewMinSizer(child fyne.CanvasObject, minsize fyne.Size) *minSizer {
	ms := &minSizer{child: child, minsize: minsize}
	ms.ExtendBaseWidget(ms)
	return ms
}

func (ms *minSizer) MinSize() fyne.Size {
	return ms.child.MinSize().Max(ms.minsize)
}

func (ms *minSizer) CreateRenderer() fyne.WidgetRenderer {
	return widget.NewSimpleRenderer(ms.child)
}

Checklist:

• Tests included.
• Lint and formatter run with no errors.
• Tests all pass.

[Jacalz]

It is fully backwards compatible.

Sorry but it actually isn’t. Your variable is indexed from one meaning that the default value of zero when creating a struct without using the constructor results in incorrect behaviour.

[BieHDC]

It is fully backwards compatible.

Sorry but it actually isn’t. Your variable is indexed from one meaning that the default value of zero when creating a struct without using the constructor results in incorrect behaviour.

True, but i can fix that. Right now i would more like to know if that feature was even wished in the main repo. Otherwise i would demote it to a new widget for fyne-x.

[Jacalz]

Absolutely, I meant it as a review comment. Sorry if that wasn't clear. I personally think it is a useful addition :)

[BieHDC]

I reworked the code on the basis of gridLayout which also fixed a rendering bug and the list now also has the natural flow. And of course fixed the backwards compatibility issue.

[coveralls]

coverage: 59.971% (+0.01%) from 59.961%
when pulling d178c85 on BieHDC:develop
into de361f6 on fyne-io:develop.