glyph_not_displayed.go

package main

import (
	"gioui.org/app"
	"gioui.org/font/gofont"
	"gioui.org/io/system"
	"gioui.org/layout"
	"gioui.org/widget"
	"gioui.org/widget/material"
)

func main() {
	go func() {
		gofont.Register()

		w := app.NewWindow()
		th := material.NewTheme()
		gtx := layout.NewContext(w.Queue())

		var button widget.Button

		for e := range w.Events() {
			if e, ok := e.(system.FrameEvent); ok {
				gtx.Reset(e.Config, e.Size)

				layout.Flex{Axis: layout.Vertical}.Layout(gtx,
					layout.Rigid(func() {
						th.Button("🗑").Layout(gtx, &button)
					}),
				)
				e.Frame(gtx.Ops)
			}
		}

	}()
	app.Main()
}