Gioui reproducer for https://todo.sr.ht/~eliasnaur/gio/602

go.mod

module demo

go 1.22

require gioui.org v0.7.1

require (
	gioui.org/cpu v0.0.0-20220412190645-f1e9e8c3b1f7 // indirect
	gioui.org/shader v1.0.8 // indirect
	github.com/go-text/typesetting v0.1.1 // indirect
	golang.org/x/exp v0.0.0-20240707233637-46b078467d37 // indirect
	golang.org/x/exp/shiny v0.0.0-20240707233637-46b078467d37 // indirect
	golang.org/x/image v0.18.0 // indirect
	golang.org/x/sys v0.22.0 // indirect
	golang.org/x/text v0.16.0 // indirect
)

main.go

package main

import (
	"gioui.org/io/system"
	"image/color"
	"log"
	"os"

	"gioui.org/app"
	"gioui.org/op"
	"gioui.org/text"
	"gioui.org/widget/material"
)

func main() {
	go func() {
		window := new(app.Window)
		window.Perform(system.ActionCenter)
		err := run(window)
		if err != nil {
			log.Fatal(err)
		}
		os.Exit(0)
	}()
	app.Main()
}

func run(window *app.Window) error {
	theme := material.NewTheme()
	var ops op.Ops
	for {
		switch e := window.Event().(type) {
		case app.DestroyEvent:
			return e.Err
		case app.FrameEvent:
			// This graphics context is used for managing the rendering state.
			gtx := app.NewContext(&ops, e)

			// Define an large label with an appropriate text:
			title := material.H1(theme, "Hello, Gio")

			// Change the color of the label.
			maroon := color.NRGBA{R: 127, G: 0, B: 0, A: 255}
			title.Color = maroon

			// Change the position of the label.
			title.Alignment = text.Middle

			// Draw the label to the graphics context.
			title.Layout(gtx)

			// Pass the drawing operations to the GPU.
			e.Frame(gtx.Ops)
		}
	}
}