internal static float CalculateYPositionForStraight(ChartValueItem firstItem, ChartValueItem secondItem, float xPosition)
{
if (secondItem == null)
{
return(firstItem.Point.Y);
}
// Difference in value
var diffVal = secondItem.Value - firstItem.Value;
// Difference in Y position
var diffY = secondItem.Point.Y - firstItem.Point.Y;
if (diffY == 0)
{
return(firstItem.Point.Y);
}
// Difference in X position
var diffX = secondItem.Point.X - firstItem.Point.X;
var yValue = diffVal / diffY;
var xValue = diffVal / diffX;
// Current X position over first item
var x = xPosition - firstItem.Point.X;
var points = x * xValue;
return((points / yValue) + firstItem.Point.Y);
}
public ChartValueItemParam(ChartValueItem chartValueItem, ChartValueItem nextChartValueItem, ChartItem parent)
{
this.ChartValueItem = chartValueItem;
this.NextChartValueItem = nextChartValueItem;
this.BackgroundColor = parent.Color;
this.TextColor = parent.TextColor;
this.Parent = parent;
}
public static float CalculateExactValue(ChartValueItem firstItem, ChartValueItem secondItem, float xPosition)
{
if (secondItem == null)
{
return(firstItem.Value);
}
// Difference in value
var diffVal = secondItem.Value - firstItem.Value;
// Difference in X position
var diffX = secondItem.Point.X - firstItem.Point.X;
var xValue = diffVal / diffX;
// Current X position over first item
var x = xPosition - firstItem.Point.X;
var points = x * xValue;
float currentVal = 0;
if (secondItem != null)
{
try
{
currentVal = firstItem.Value + (int)Math.Round(decimal.Parse(points.ToString()), 0, MidpointRounding.AwayFromZero);
}
catch (Exception ex)
{
ex.Print();
}
if (xPosition == firstItem.Point.X)
{
currentVal = firstItem.Value;
}
else if (xPosition == secondItem?.Point.X)
{
currentVal = secondItem.Value;
}
}
else
{
currentVal = firstItem.Value;
}
return(currentVal);
}
internal static SKPoint CalculateYPositionForSpline(ChartValueItem firstItem, ChartValueItem secondItem, float xPosition)
{
if (secondItem == null)
{
//return firstItem.Point.Y;
return(firstItem.Point);
}
var y = CalculateYPositionForStraight(firstItem, secondItem, xPosition).ToRounded();
var point = firstItem.Point;
var nextPoint = secondItem.Point;
var offsetPoint = new SKPoint((nextPoint.X - point.X) * .5f, 0);
var currentPoint = point + offsetPoint;
var next = nextPoint - offsetPoint;
float diffY;
// Difference in Y position
diffY = (firstItem.Point.Y > secondItem.Point.Y ? firstItem.Point.Y - secondItem.Point.Y : secondItem.Point.Y - firstItem.Point.Y).ToRounded();
if (diffY == 0)
{
return(new SKPoint(xPosition, firstItem.Point.Y));
}
var insideY = y > firstItem.Point.Y ? y - firstItem.Point.Y.ToRounded() : firstItem.Point.Y - y;
var t = (insideY / diffY).ToRounded(2);
var beziers = HandleBezier(point, currentPoint, next, nextPoint, t);
var doits = DoIt(point.X, point.Y, currentPoint.X, currentPoint.Y, next.X, next.Y, nextPoint.X, nextPoint.Y, t);
return(doits);
}
public static IList <ChartValueItemParam> GetChartValueItemFromX(this IList <ChartItem> chartItems, float xPosition, SKRect frame, float itemWidth)
{
var items = new List <ChartValueItemParam>();
if (chartItems?.Any(x => x.IsVisible) != true)
{
return(items);
}
foreach (var chartEntry in chartItems.Where(x => x.Items?.Any() == true && x.IsVisible))
{
var valueItems = chartEntry.Items;
ChartValueItem item = null;
if (true)
{
// Order list and takes the first that's lower then X value
item = valueItems.OrderByDescending(c => c.Point.X).FirstOrDefault(c => c.Point.X <= xPosition);
}
else
{
// Create a bound and get item inside this bound
foreach (var valueItem in valueItems)
{
SKRect rect = new SKRect((xPosition - (itemWidth / 2)), 0, (xPosition + (itemWidth / 2)), frame.Bottom + 2);
if (rect.Contains(valueItem.Point))
{
item = valueItem;
}
}
}
// No item found so check if we touched left of the frame
if (item == null)
{
item = valueItems.FirstOrDefault();
if ((xPosition <= frame.Left && item.Point.X == frame.Left))
{
items.Add(new ChartValueItemParam(item, null, chartEntry));
}
continue;
}
// Get the index of the found item
int index = valueItems.ToList().IndexOf(item);
// It's the last item in the list so add just the this entry
if (index + 1 >= valueItems.Count())
{
if ((xPosition >= frame.Right && item.Point.X == frame.Right) || item.Point.X >= (xPosition - (itemWidth / 2)))
{
items.Add(new ChartValueItemParam(item, null, chartEntry));
}
continue;
}
// Takes the next item in the list
var nextItem = valueItems.ToList()[index + 1];
if (item != null)
{
// Add current item, next item and parents line color
items.Add(new ChartValueItemParam(item, nextItem, chartEntry));
}
}
return(items);
}
protected void DrawHorizontalLabel(ChartValueItem entry, SKCanvas canvas, SKRect frame, SKRect chart)
{
if (!DisplayHorizontalValuesBySlider)
{
return;
}
// Draws the horizontal value the slider is on //
if (string.IsNullOrEmpty(entry?.Label))
{
return;
}
float x = chart.GetInsideXValue(TouchedPoint.X);
if (ChartType == ChartType.Bar)
{
x = entry.Point.X;
}
// Draws background
using (var boundPaint = new SKPaint
{
Color = SliderColor.ToSKColor(),
StrokeCap = SKStrokeCap.Round,
Style = SKPaintStyle.StrokeAndFill,
StrokeWidth = SliderWidth
})
{
var bounds = boundPaint.GetBounds(
entry.Label,
x,
frame.Bottom + HorizontalTextSize + (HorizontalTextSize / 4),
padding: InternalSliderDetailPadding);
if (bounds.Right > frame.Right)
{
bounds.Left = frame.Right - bounds.Width + SliderWidth;
bounds.Right = frame.Right + SliderWidth;
}
else if (bounds.Left < frame.Left)
{
bounds.Right = frame.Left + bounds.Width - SliderWidth;
bounds.Left = frame.Left - SliderWidth;
}
canvas.DrawRoundRect(new SKRoundRect(bounds, SliderDetailCornerRadius), boundPaint);
// Draws text
using (var textPaint = new SKPaint
{
IsAntialias = true,
TextSize = HorizontalTextSize,
Color = SliderDetailTextColor.ToSKColor(),
Typeface = FontTypeService.GetFontFamily(GetType().Assembly),
TextAlign = SKTextAlign.Center,
FakeBoldText = true
})
{
canvas.DrawText(entry.Label, bounds.MidX, bounds.MidY + (bounds.Height / 4), textPaint);
}
}
}
