Android SpanUtils - LeadingMarginSpan with Images

DrawableMarginSpan.kt

internal class DrawableMarginSpan : LeadingMarginSpan {
    private val bitmap: Bitmap
    private val verticalAlignment: Int
    private val padding: Int
    private val totalHeight = 0

    constructor(bitmap: Bitmap, pad: Int, verticalAlignment: Int) {
        this.bitmap = bitmap
        padding = pad
        this.verticalAlignment = verticalAlignment
    }

    constructor(drawable: Drawable, pad: Int, verticalAlignment: Int) {
        bitmap = drawable2Bitmap(drawable)
        padding = pad
        this.verticalAlignment = verticalAlignment
    }

    constructor(uri: Uri, pad: Int, verticalAlignment: Int) {
        bitmap = uri2Bitmap(uri)
        padding = pad
        this.verticalAlignment = verticalAlignment
    }

    constructor(resourceId: Int, pad: Int, verticalAlignment: Int) {
        bitmap = resource2Bitmap(resourceId)
        padding = pad
        this.verticalAlignment = verticalAlignment
    }

    private fun drawable2Bitmap(drawable: Drawable): Bitmap {
        if (drawable is BitmapDrawable) {
            if (drawable.bitmap != null) {
                return drawable.bitmap
            }
        }
        val bitmap: Bitmap = if (drawable.intrinsicWidth <= 0 || drawable.intrinsicHeight <= 0) {
            Bitmap.createBitmap(
                1, 1,
                if (drawable.opacity != PixelFormat.OPAQUE) Bitmap.Config.ARGB_8888 else Bitmap.Config.RGB_565
            )
        } else {
            Bitmap.createBitmap(
                drawable.intrinsicWidth, drawable.intrinsicHeight,
                if (drawable.opacity != PixelFormat.OPAQUE) Bitmap.Config.ARGB_8888 else Bitmap.Config.RGB_565
            )
        }
        val canvas = Canvas(bitmap)
        drawable.setBounds(0, 0, canvas.width, canvas.height)
        drawable.draw(canvas)
        return bitmap
    }

    private fun uri2Bitmap(uri: Uri): Bitmap {
        return try {
            MediaStore.Images.Media.getBitmap(instance.contentResolver, uri)
        } catch (e: IOException) {
            e.printStackTrace()
            Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888)
        }
    }

    private fun resource2Bitmap(resourceId: Int): Bitmap {
        val drawable = ContextCompat.getDrawable(instance, resourceId)
        val canvas = Canvas()
        val bitmap = Bitmap.createBitmap(drawable!!.intrinsicWidth, drawable.intrinsicHeight, Bitmap.Config.ARGB_8888)
        canvas.setBitmap(bitmap)
        drawable.setBounds(0, 0, drawable.intrinsicWidth, drawable.intrinsicHeight)
        drawable.draw(canvas)
        return bitmap
    }

    override fun getLeadingMargin(first: Boolean): Int {
        return bitmap.width + padding
    }

    override fun drawLeadingMargin(
        c: Canvas,
        p: Paint,
        x: Int,
        dir: Int,
        top: Int,
        baseline: Int,
        bottom: Int,
        text: CharSequence,
        start: Int,
        end: Int,
        first: Boolean,
        layout: Layout
    ) {
        var x = x
        val st = (text as Spanned).getSpanStart(this)
        val itop = layout.getLineTop(layout.getLineForOffset(st))
        if (dir < 0) x -= bitmap.width
        val delta = totalHeight - bitmap.height
        if (delta > 0) {
            if (verticalAlignment == ALIGN_TOP) {
                c.drawBitmap(bitmap, x.toFloat(), itop.toFloat(), p)
            } else if (verticalAlignment == ALIGN_CENTER) {
                c.drawBitmap(bitmap, x.toFloat(), (itop + delta / 2).toFloat(), p)
            } else {
                c.drawBitmap(bitmap, x.toFloat(), (itop + delta).toFloat(), p)
            }
        } else {
            c.drawBitmap(bitmap, x.toFloat(), itop.toFloat(), p)
        }
    }

    companion object {
        const val ALIGN_CENTER = 2
        const val ALIGN_TOP = 3
    }
}