protected override void OnSizeChanged(int w, int h, int oldw, int oldh)
{
base.OnSizeChanged(w, h, oldw, oldh);
_length = w > h ? h : w;
var thickness = _length / 20;
_rectBackground = new RectF(thickness / 2, thickness / 2, _length - thickness / 2, _length - thickness / 2);
if (_separateProgressFromItsBackground)
{
_rectForeground = new RectF(thickness * 3 / 2, thickness * 3 / 2, _length - thickness * 3 / 2,
_length - thickness * 3 / 2);
}
else
{
_rectForeground = _rectBackground;
}
_percentagePaint.TextSize = _length / 6;
_textPaint.TextSize = _length / 8;
_backgroundWidth = thickness;
_progressWidth = thickness;
_arcPaintBackground.StrokeWidth = _backgroundWidth;
_arcPaintProgress.StrokeWidth = _progressWidth;
var gradientRadius = _length / 2;
var sweepOffsetIndex = GetSweep() / 360.0f;
var sweepGradient = new SweepGradient(gradientRadius, gradientRadius,
new int[] { Color.Red, Color.Yellow, Color.Yellow, Color.Green },
new[] { 0.0f, 0.375f * sweepOffsetIndex, 0.625f * sweepOffsetIndex, sweepOffsetIndex });
if (_startAngle != 0)
{
var matrix = new Matrix();
matrix.SetRotate(_startAngle - 0.5f, gradientRadius,
gradientRadius); // There is some issues with floating calculations, which affects gradient draw. Thus - 0.5f to hide it.
sweepGradient.SetLocalMatrix(matrix);
}
_arcPaintProgress.SetShader(sweepGradient);
if (ArrowDrawable != null)
{
_arrowBitmap = Bitmap.CreateBitmap(_length, _length, Bitmap.Config.Argb8888);
_arrowCanvas = new Canvas(_arrowBitmap);
var arrowSize = thickness * 3;
var arrowLeftPos = _length - thickness - arrowSize;
var arrowTopPos = _length / 2 - arrowSize / 2;
if (_separateProgressFromItsBackground)
{
arrowLeftPos -= thickness;
}
var arrowRightPos = arrowLeftPos + arrowSize;
var arrowBottomPos = arrowTopPos + arrowSize;
ArrowDrawable.SetBounds(arrowLeftPos, arrowTopPos, arrowRightPos, arrowBottomPos);
ArrowDrawable.Draw(_arrowCanvas);
}
}
//@SuppressLint("DrawAllocation")
//@Override
protected override void OnDraw(Canvas canvas)
{
int centerX = Width / 2;
int centerY = Height / 2;
// drawing color wheel
canvas.DrawBitmap(colorWheelBitmap, centerX - colorWheelRadius, centerY - colorWheelRadius, null);
// drawing color view
colorViewPaint.Color = Color.HSVToColor(colorHSV);
canvas.DrawPath(colorViewPath, colorViewPaint);
// drawing value slider
float[] hsv = new float[] { colorHSV[0], colorHSV[1], 1f };
SweepGradient sweepGradient = new SweepGradient(centerX, centerY, new int[] { Color.Black, Color.HSVToColor(hsv), Color.White }, null);
sweepGradient.SetLocalMatrix(gradientRotationMatrix);
valueSliderPaint.SetShader(sweepGradient);
canvas.DrawPath(valueSliderPath, valueSliderPaint);
// drawing color wheel pointer
float hueAngle = (float)Math.ToRadians(colorHSV[0]);
int colorPointX = (int)(-Math.Cos(hueAngle) * colorHSV[1] * colorWheelRadius) + centerX;
int colorPointY = (int)(-Math.Sin(hueAngle) * colorHSV[1] * colorWheelRadius) + centerY;
float pointerRadius = 0.075f * colorWheelRadius;
int pointerX = (int)(colorPointX - pointerRadius / 2);
int pointerY = (int)(colorPointY - pointerRadius / 2);
colorPointerCoords.Set(pointerX, pointerY, pointerX + pointerRadius, pointerY + pointerRadius);
canvas.DrawOval(colorPointerCoords, colorPointerPaint);
// drawing value pointer
valuePointerPaint.Color = Color.HSVToColor(new float[] { 0f, 0f, 1f - colorHSV[2] });
double valueAngle = (colorHSV[2] - 0.5f) * Math.Pi;
float valueAngleX = (float)Math.Cos(valueAngle);
float valueAngleY = (float)Math.Sin(valueAngle);
canvas.DrawLine(valueAngleX * innerWheelRadius + centerX, valueAngleY * innerWheelRadius + centerY, valueAngleX * outerWheelRadius + centerX,
valueAngleY * outerWheelRadius + centerY, valuePointerPaint);
// drawing pointer arrow
if (arrowPointerSize > 0)
{
drawPointerArrow(canvas);
}
}
