attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="ClipBoxView">
        <attr name="ratio_width" format="float" />
        <attr name="ratio_height" format="float" />
        <attr name="border_width" format="integer" />
        <attr name="border_color" format="color" />
        <attr name="frame_color" format="color" />
    </declare-styleable>
</resources>

ClipBoxView.kt

import android.content.Context
import android.graphics.Canvas
import android.graphics.Color
import android.graphics.Paint
import android.graphics.Region
import android.os.Build
import android.util.AttributeSet
import android.view.View

class ClipBoxView(ctx: Context, attrs: AttributeSet) : View(ctx, attrs) {

    private val frameBoxPaint = Paint(Paint.ANTI_ALIAS_FLAG).apply {
        style = Paint.Style.FILL
    }

    private val borderBoxPaint = Paint(Paint.ANTI_ALIAS_FLAG).apply {
        style = Paint.Style.FILL
    }

    private var mWidthRatio = 1f / 10f
    private var mHeightRatio = 1f / 4f

    private var mBorderWidth = 2

    init {
        context.theme.obtainStyledAttributes(
            attrs,
            R.styleable.ClipBoxView,
            0, 0
        ).apply {
            mWidthRatio = 1f / getFloat(R.styleable.ClipBoxView_ratio_width, 10f)
            mHeightRatio = 1f / getFloat(R.styleable.ClipBoxView_ratio_height, 4f)
            mBorderWidth = getInteger(R.styleable.ClipBoxView_border_width, 2)

            borderBoxPaint.color = getColor(
                    R.styleable.ClipBoxView_border_color,
                    Color.parseColor("#FF0000")
            )

            frameBoxPaint.color = getColor(
                    R.styleable.ClipBoxView_frame_color,
                    Color.parseColor("#55000000")
            )
        }
    }

    override fun onDraw(canvas: Canvas?) {
        super.onDraw(canvas)

        canvas?.apply {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                clipOutRect(
                    width * mWidthRatio,
                    height * mHeightRatio,
                    width * (1f - mWidthRatio),
                    height * (1f - mHeightRatio)
                )
            } else {
                clipRect(
                    width * mWidthRatio,
                    height * mHeightRatio,
                    width * (1f - mWidthRatio),
                    height * (1f - mHeightRatio),
                    Region.Op.DIFFERENCE
                )
            }

            drawRect(0f, 0f, width * 1f, height * 1f, frameBoxPaint)
            drawRect(
                width * mWidthRatio - mBorderWidth,
                height * mHeightRatio - mBorderWidth,
                width * (1f - mWidthRatio) + mBorderWidth,
                height * (1f - mHeightRatio) + mBorderWidth,
                borderBoxPaint
            )
        }
    }

}