convert QROverlay to Kotlin

app/src/main/java/app/attestation/auditor/QROverlay.kt

@@ -0,0 +1,121 @@
+package app.attestation.auditor
+
+import android.content.Context
+import android.graphics.Canvas
+import android.graphics.Color
+import android.graphics.Paint
+import android.graphics.PorterDuff
+import android.graphics.PorterDuffXfermode
+import android.text.TextPaint
+import android.util.AttributeSet
+import android.view.View
+import app.attestation.auditor.R
+
+class QROverlay(context: Context?, attrs: AttributeSet?) : View(context, attrs) {
+    companion object {
+        private const val TAG = "QROverlay"
+        private const val T_SIZE = 24f
+        private const val SIZE_FACTOR = 0.6f
+    }
+
+    private var bPaint: Paint
+    private var tPaint: TextPaint
+    private var fPaint: Paint
+    var size = 256
+        private set
+    private var frameSideSize = 3
+    private var frameSideLength = 42
+
+    init {
+        frameSideSize *= resources.displayMetrics.density.toInt()
+        frameSideLength *= resources.displayMetrics.density.toInt()
+        bPaint = Paint()
+        bPaint.color = Color.parseColor("#A6000000")
+        bPaint.strokeWidth = 10f
+        bPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC)
+        tPaint = TextPaint()
+        tPaint.color = Color.parseColor("#ffffff")
+        fPaint = Paint()
+        fPaint.color = Color.parseColor("#8BC34A") // green500
+        fPaint.strokeWidth = frameSideSize.toFloat()
+    }
+
+    override fun onDraw(canvas: Canvas) {
+        super.onDraw(canvas)
+        val dim = Math.min(width, height)
+        size = (dim * SIZE_FACTOR).toInt()
+        tPaint.textSize = T_SIZE * SIZE_FACTOR * resources.displayMetrics.density
+        val verticalHeight = (height - size) / 2
+        val horizontalWidth = (width - size) / 2
+
+        // Drawing the background
+        canvas.drawRect(0f, 0f, width.toFloat(), verticalHeight.toFloat(), bPaint)
+        canvas.drawRect(0f, 0f, horizontalWidth.toFloat(), height.toFloat(), bPaint)
+        canvas.drawRect((horizontalWidth + size).toFloat(), 0f, width.toFloat(), height.toFloat(), bPaint)
+        canvas.drawRect(0f,
+            (verticalHeight + size).toFloat(),
+            width.toFloat(),
+            height.toFloat(),
+            bPaint
+        )
+        val text = context.getString(R.string.scanner_label)
+        val textX = horizontalWidth + size / 2
+        val textY = verticalHeight + size + frameSideSize * 4
+        val xPos = textX - (tPaint.measureText(text) / 2).toInt()
+        val yPos = (textY - (tPaint.descent() + tPaint.ascent()) / 2).toInt()
+        canvas.drawText(text, xPos.toFloat(), yPos.toFloat(), tPaint)
+
+        // Drawing the frame
+        val halfFrameSideSize = frameSideSize / 2
+        val x1 = width - horizontalWidth
+        val y1 = height - verticalHeight
+
+        // Top left
+        canvas.drawLine(
+            horizontalWidth.toFloat(), (verticalHeight + halfFrameSideSize).toFloat(),
+            (horizontalWidth + frameSideLength).toFloat(), (verticalHeight + halfFrameSideSize).toFloat(),
+            fPaint
+        )
+        canvas.drawLine(
+            (horizontalWidth + halfFrameSideSize).toFloat(), verticalHeight.toFloat(),
+            (horizontalWidth + halfFrameSideSize).toFloat(), (verticalHeight + frameSideLength).toFloat(),
+            fPaint
+        )
+
+        // Top right
+        canvas.drawLine(
+            x1.toFloat(), (verticalHeight + halfFrameSideSize).toFloat(),
+            (x1 - frameSideLength).toFloat(), (verticalHeight + halfFrameSideSize).toFloat(),
+            fPaint
+        )
+        canvas.drawLine(
+            (x1 - halfFrameSideSize).toFloat(), verticalHeight.toFloat(),
+            (x1 - halfFrameSideSize).toFloat(), (verticalHeight + frameSideLength).toFloat(),
+            fPaint
+        )
+
+        // Bottom left
+        canvas.drawLine(
+            horizontalWidth.toFloat(), (y1 - halfFrameSideSize).toFloat(),
+            (horizontalWidth + frameSideLength).toFloat(), (y1 - halfFrameSideSize).toFloat(),
+            fPaint
+        )
+        canvas.drawLine(
+            (horizontalWidth + halfFrameSideSize).toFloat(), y1.toFloat(),
+            (horizontalWidth + halfFrameSideSize).toFloat(), (y1 - frameSideLength).toFloat(),
+            fPaint
+        )
+
+        // Bottom right
+        canvas.drawLine(
+            (x1 - halfFrameSideSize).toFloat(), y1.toFloat(),
+            (x1 - halfFrameSideSize).toFloat(), (y1 - frameSideLength).toFloat(),
+            fPaint
+        )
+        canvas.drawLine(
+            x1.toFloat(), (y1 - halfFrameSideSize).toFloat(),
+            (x1 - frameSideLength).toFloat(), (y1 - halfFrameSideSize).toFloat(),
+            fPaint
+        )
+    }
+}