public SKPaint GetTextBrush(GraphText graphText)
{
SKPaint brush;
string key = $"{graphText.Color}{graphText.PointSize}{graphText.Alignment}{graphText.Bold}";
if (textBrushes.ContainsKey(key))
{
brush = textBrushes[key];
}
else
{
SKTextAlign alignment = SKTextAlign.Left;
switch (graphText.Alignment)
{
case TextAlignment.End:
alignment = SKTextAlign.Right;
break;
case TextAlignment.Center:
alignment = SKTextAlign.Center;
break;
}
brush = new SKPaint
{
Color = graphText.Color,
TextSize = graphText.PointSize,
TextAlign = alignment,
FakeBoldText = graphText.Bold
};
textBrushes[key] = brush;
}
return(brush);
}
protected virtual void DrawLeftLabel(List <IGraphItem> graphItems, float graphHeight, float scale, float yPos)
{
if (ViewModel.LeftLabel == null || string.IsNullOrWhiteSpace(ViewModel.LeftLabel.Text))
{
return;
}
SKPaint leftLabelBrush = CreateLeftLabelBrush(scale); // Needed to determine graph width, taking into account Y-Label max width.
var graphText = new GraphText
{
Rotation = 270,
Alignment = ViewModel.LeftLabel.TextAlignment,
Color = ViewModel.LeftLabel.Color,
PointSize = ViewModel.LeftLabel.PointSize * scale,
Text = ViewModel.LeftLabel.Text,
XPos = ViewModel.LeftLabel.Height,
Bold = ViewModel.LeftLabel.Bold
};
switch (ViewModel.LeftLabel.TextAlignment)
{
case TextAlignment.Start:
graphText.YPos = yPos + graphHeight;
break;
case TextAlignment.Center:
graphText.YPos = yPos + graphHeight / 2;
break;
case TextAlignment.End:
graphText.YPos = yPos;
break;
}
graphItems.Add(graphText);
}
public void Draw(SKSurface surface, List <IGraphItem> graphItems)
{
SKCanvas canvas = surface.Canvas;
foreach (var item in graphItems)
{
string type = item.GetType().ToString();
int pos = type.LastIndexOf('.');
type = type.Substring(pos + 1);
switch (type)
{
case "GraphClear":
GraphClear graphClear = item as GraphClear;
canvas.Clear(graphClear.Color);
break;
case "GraphLine":
GraphLine graphLine = item as GraphLine;
canvas.DrawLine(graphLine.XPosStart, graphLine.YPosStart, graphLine.XPosEnd, graphLine.YPosEnd, GetLineBrush(graphLine));
break;
case "GraphRectangle":
GraphRectangle graphRectangle = item as GraphRectangle;
var rect = SKRect.Create(graphRectangle.XPos, graphRectangle.YPos, graphRectangle.Width, graphRectangle.Height);
canvas.DrawRect(rect, GetRectangleBrush(graphRectangle));
break;
case "GraphText":
GraphText graphText = item as GraphText;
if (graphText.Rotation == 0)
{
canvas.DrawText(graphText.Text, graphText.XPos, graphText.YPos, GetTextBrush(graphText));
}
else
{
using (new SKAutoCanvasRestore(canvas)) // https://stackoverflow.com/questions/41908497/draw-rotated-text-in-skiasharp
{
// do any transformations
canvas.RotateDegrees(graphText.Rotation, graphText.XPos, graphText.YPos);
// do serious work
canvas.DrawText(graphText.Text, graphText.XPos, graphText.YPos, GetTextBrush(graphText));
// auto restore, even on exceptions or errors
}
}
break;
case "GraphCircle":
GraphCircle graphCircle = item as GraphCircle;
canvas.DrawCircle(graphCircle.XPos, graphCircle.YPos, graphCircle.Radius, GetCircleBrush(graphCircle));
break;
}
}
}
public override void Begin()
{
Temp = new GraphText();
}