How to draw a dot on fyne (go) canvas?

Question

go

application on go. fyne.io

is used as GUI

package main

import (
  "image/color"
  "fyne.io/fyne/v2/app"
  "fyne.io/fyne/v2/canvas"
)

func main() {
  a := app.New()
  w := a.NewWindow("The dots")
  cnvs := w.Canvas()

  red := color.NRGBA{255, 0, 0, 128}
  // blue := color.NRGBA{0, 0, 255, 128}
  rect := canvas.NewRectangle(red)
  cnvs.SetContent(rect)

  // Здесь хочется перекрасить пиксель в координатах х=50; у=80 в синий цвет
  // cnvs.SetPixel(blue, 50, 80)

  w.ShowAndRun()
}

In the code, I commented out the pseudo-method in search of which I turned to you

Answer 1

See the canvas.Raster part :

raster := canvas.NewRasterWithPixels(
    func(_, _, w, h int) color.Color {
      return color.RGBA{uint8(rand.Intn(255)),
        uint8(rand.Intn(255)),
        uint8(rand.Intn(255)), 0xff}
    })