private void DrawTriangle(Canvas c, float startAngle, float sweepAngle, Rect bounds)
{
if (mShowArrow)
{
if (mArrow == null)
{
mArrow = new Path();
mArrow.SetFillType(Path.FillType.EvenOdd);
}
else
{
mArrow.Reset();
}
float x = (float)(RingCenterRadius * Math.Cos(0) + bounds.ExactCenterX());
float y = (float)(RingCenterRadius * Math.Sin(0) + bounds.ExactCenterY());
mArrow.MoveTo(0, 0);
mArrow.LineTo((mArrowWidth) * mArrowScale, 0);
mArrow.LineTo(((mArrowWidth) * mArrowScale / 2), (mArrowHeight * mArrowScale));
mArrow.Offset(x - ((mArrowWidth) * mArrowScale / 2), y);
mArrow.Close();
mArrowPaint.Color = mColors[mColorIndex];
c.Rotate(startAngle + (sweepAngle < 0 ? 0 : sweepAngle) - ARROW_OFFSET_ANGLE, bounds.ExactCenterX(), bounds.ExactCenterY());
c.DrawPath(mArrow, mArrowPaint);
}
}
protected override void OnDraw(Canvas canvas)
{
if (Element != null && Element.Text != null)
{
var density = DeviceDisplay.MainDisplayInfo.Density;
float strokeWidth = Convert.ToSingle(Element.StrokeWidth * density);
float strokeMiter = 10.0f;
var rect = new Android.Graphics.Rect();
this.GetDrawingRect(rect);
float progressAngle = 360 * Convert.ToSingle(Element.Progress / Element.Total);
float radius = Math.Min(rect.Height(), rect.Width()) / 2 - strokeWidth;
RectF circleRect = new RectF(
rect.ExactCenterX() - radius,
rect.ExactCenterY() - radius,
rect.ExactCenterX() + radius,
rect.ExactCenterY() + radius
);
TextPaint paint = new TextPaint();
paint.Color = Element.TextColor.ToAndroid();
paint.TextSize = Element.TextSize;
paint.GetTextBounds(Element.Text.ToString(), 0, Element.Text.ToString().Length, rect);
if (((this.Width / 2) - (Element.TextMargin * 4)) < rect.Width())
{
float ratio = (float)((this.Width / 2) - Element.TextMargin * 4) / (float)rect.Width();
paint.TextSize = paint.TextSize * ratio;
paint.GetTextBounds(Element.Text.ToString(), 0, Element.Text.ToString().Length, rect);
}
int x = this.Width / 2 - rect.CenterX();
int y = this.Height / 2 - rect.CenterY();
Paint progressPaint = new Paint(PaintFlags.AntiAlias)
{
StrokeWidth = strokeWidth,
StrokeMiter = strokeMiter,
Color = Element.ProgressStrokeColor.ToAndroid()
};
progressPaint.SetStyle(Paint.Style.Stroke);
Paint availablePaint = new Paint(PaintFlags.AntiAlias)
{
StrokeWidth = strokeWidth,
StrokeMiter = strokeMiter,
Color = Element.AvailableStrokeColor.ToAndroid()
};
availablePaint.SetStyle(Paint.Style.Stroke);
Paint paintCircle = new Paint(PaintFlags.AntiAlias)
{
Color = Element.FillColor.ToAndroid()
};
canvas.DrawArc(circleRect, -90, progressAngle, false, progressPaint);
canvas.DrawArc(circleRect, -90 + progressAngle, 360 - progressAngle, false, availablePaint);
canvas.DrawText(Element.Text.ToString(), x, y, paint);
}
}
public void Draw(Canvas c, Rect bounds)
{
RectF arcBounds = mTempBounds;
arcBounds.Set(bounds);
arcBounds.Inset(mStrokeInset, mStrokeInset);
float startAngle = (mStartTrim + mRotation) * 360;
float endAngle = (mEndTrim + mRotation) * 360;
float sweepAngle = endAngle - startAngle;
mPaint.Color = mColors[mColorIndex];
c.DrawArc(arcBounds, startAngle, sweepAngle, false, mPaint);
DrawTriangle(c, startAngle, sweepAngle, bounds);
if (Alpha < 255)
{
mCirclePaint.Color = BackgrounColor;
mCirclePaint.Alpha = 255 - Alpha;
c.DrawCircle(bounds.ExactCenterX(), bounds.ExactCenterY(), bounds.Width() / 2, mCirclePaint);
}
}
static bool IsWithinCircularBounds(Rect hit, Rect bounds)
{
if (!bounds.Contains(hit)) return false;
// Forumula for a circle: (x-a)2 + (y-b)2 = r2
var centerX = bounds.ExactCenterX() - bounds.Left;
var centerY = bounds.ExactCenterY() - bounds.Top;
var radius = centerX;
double x = hit.Left - bounds.Left,
y = hit.Top - bounds.Top,
r2 = radius * radius,
xx = (x - centerX);
var yy = Math.Sqrt(r2 - xx*xx) + 0.5;
var upperBound = centerY - yy;
var lowerBound = centerY + yy;
var result = !Double.IsNaN (y) && y > upperBound && y < lowerBound;
return result;
}