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junior
Asked: 2022-05-23 05:04:47 +0800 CST 2022-05-23 05:04:47 +0800 CST

How to clone PAINT object in kotlin

  • 772

Hello, I am creating a drawable with canvasKotlin but I would like to reduce the code and I have many paints:

        val lado=440 // preferiblemente un multiplo de 8
        val ladmit=lado/2f
        val textmed=(ladmit*resources.displayMetrics.density/4)+6
        val bitmap: Bitmap = Bitmap.createBitmap(lado, lado, Bitmap.Config.ARGB_8888)
        bitmap.density=resources.displayMetrics.densityDpi
        bitmap.eraseColor(Color.argb(0,0,0,0))
        val canva = Canvas(bitmap)
        canva.drawColor(Color.argb(0, 0, 0, 0));
        val pback :Paint= Paint().apply {
            isAntiAlias = true
            style = Paint.Style.FILL
            color = Color.WHITE
            setShadowLayer(10f, -5f, -5f, Color.GRAY)
        }
        val pcol :Paint= Paint().apply {
            isAntiAlias = true
            style = Paint.Style.FILL
            color= "FFCC80".toInt(16) - 0xffffff
        }
        val pbord = Paint().apply {
            isAntiAlias = true
            style = Paint.Style.STROKE
            color = Color.BLACK
            strokeWidth=4f
        }
        val p = Paint().apply{
            color=Color.BLACK
            textSize=textmed
            textAlign=Paint.Align.CENTER
        }
        RectF(10f, 10f, lado-10f, lado-10f).let {
            canva.drawRoundRect(it, 25f, 25f, pback)
            canva.drawRoundRect(RectF(10f, 10f, lado-10f, ladmit), 25f, 25f, pcol)
            canva.drawRoundRect(it, 25f, 25f, pbord)
        }
        RectF(10f, ladmit/2+10f, lado/2f, lado/2f).let {
            pcol.color= Color.WHITE
            canva.drawRoundRect(it, 0f, 0f, pcol)
            canva.drawRoundRect(it, 0f, 0f, pbord)
        }
        RectF(ladmit, ladmit/2+10f, lado-10f, ladmit).let {
            pcol.color= "80CBC4".toInt(16) - 0xffffff
            canva.drawRoundRect(it, 0f, 0f, pcol)
            canva.drawRoundRect(it, 0f, 0f, pbord)
        }
        p.typeface = Typeface.create(Typeface.DEFAULT, Typeface.BOLD)
        canva.drawText((Math.random() * 50).toInt().toString(), ladmit, lado*0.75f+p.textSize/(2*resources.displayMetrics.density), p)
        p.textSize= (textmed*0.6).toFloat()
        canva.drawText("001", ladmit/2, (ladmit-10f)*0.75f+p.textSize/2, p)
        canva.drawText("IZQ", ladmit, (ladmit-10f)/4+p.textSize/2, p)
        canva.drawText("01", lado*0.75f, (ladmit-10f)*0.75f+p.textSize/2, p)
        val draw:Drawable =bitmap.toDrawable(resources)
        binding.imageView.setImageDrawable(draw)

this is the result

enter image description here

I would also like 44 to be the only text with bold, try also{}but it changes the attribute of the instance

canva.drawText(..., p.also {
            it.typeface = Typeface.create(Typeface.DEFAULT, Typeface.BOLD)
        })

Could someone tell me how I can clone this instance of paint

android-studio

2 Answers

  1. Best Answer

    The class Painthas a constructor that accepts an object Paintas a parameter and is designed precisely for cloning. But if you also want to save the apply, you can create an extension function

    inline fun Paint.clone(change: Paint.() -> Unit) = Paint(this).also(change)

    Usage would be like this

    val default = Paint().apply {
    isAntiAlias = true
    color = Color.WHITE
    style = Style.FILL
    textSize = textmed
    textAlign = Align.CENTER
}
default.clone {
    color = "FFCC80".toInt(16) - 0xffffff
}

    if you want to modify a default value so that the next instances have it, you simply change that property

    default.color = Color.BLACK

    You could also create a builder for when you want to create without cloning

    inline fun paint(builder: (Paint.() -> Unit)) = Paint().also(builder)

    and then you use it like this

    val default = paint {
    isAntiAlias = true
    color = Color.WHITE
    style = Style.FILL
    textSize = textmed
    textAlign = Align.CENTER
}
    • 1

  2. after two hours I managed to do what I wanted and here it is:

        val paintfill=(object{
        var defcol = Color.WHITE
        open inner class default : Paint() {
            init {
                    isAntiAlias = true
                    color = defcol
                    style = Style.FILL
                    textSize=textmed
                    textAlign=Align.CENTER
            }
        }
        inner class clone : default()
    })

    this anonymous class is capable of assigning default values ​​to a class and if you need a current image of the object you just call clone and here you can modify what you want without altering the other examples:

    paintfill.clone().apply {color = "FFCC80".toInt(16) - 0xffffff}// no se modificaran las demas instancias

    Now what if you want to modify a default value so that from now on all instances have it, easy, you simply define that value that can change in the anonymous class as I did with defcol:

    paintfill.defcol = Color.BLACK // ahora todas las instancias van a tener ese valor por defecto
    • 0