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@DanishAmjad12
Created October 10, 2021 13:24
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class Drawing @JvmOverloads constructor(
context: Context?,
attributeSet: AttributeSet? = null
) :
View(context, attributeSet) {
private val currentStrokePaint: Paint = Paint()
private val canvasPaint: Paint
private val currentStroke: Path
private lateinit var drawCanvas: Canvas
private lateinit var canvasBitmap: Bitmap
override fun onSizeChanged(
width: Int,
height: Int,
oldWidth: Int,
oldHeight: Int
) {
canvasBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
drawCanvas = Canvas(canvasBitmap)
invalidate()
}
override fun onDraw(canvas: Canvas) {
canvas.drawBitmap(canvasBitmap, 0f, 0f, canvasPaint)
canvas.drawPath(currentStroke, currentStrokePaint)
}
override fun onTouchEvent(event: MotionEvent): Boolean {
val action = event.actionMasked
val x = event.x
val y = event.y
when (action) {
MotionEvent.ACTION_DOWN -> currentStroke.moveTo(x, y)
MotionEvent.ACTION_MOVE -> currentStroke.lineTo(x, y)
MotionEvent.ACTION_UP -> {
currentStroke.lineTo(x, y)
drawCanvas.drawPath(currentStroke, currentStrokePaint)
currentStroke.reset()
}
else -> {
}
}
StrokeManager.addNewTouchEvent(event)
invalidate()
return true
}
companion object {
private const val STROKE_WIDTH_DP = 5
}
init {
currentStrokePaint.color = -0x1000000 // black
currentStrokePaint.isAntiAlias = true
// Set stroke width based on display density.
currentStrokePaint.strokeWidth = TypedValue.applyDimension(
TypedValue.COMPLEX_UNIT_DIP,
STROKE_WIDTH_DP.toFloat(),
resources.displayMetrics
)
currentStrokePaint.style = Paint.Style.STROKE
currentStrokePaint.strokeJoin = Paint.Join.ROUND
currentStrokePaint.strokeCap = Paint.Cap.ROUND
currentStroke = Path()
canvasPaint = Paint(Paint.DITHER_FLAG)
}
fun clear() {
currentStroke.reset()
onSizeChanged(
canvasBitmap.width,
canvasBitmap.height,
canvasBitmap.width,
canvasBitmap.height
)
}
}
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