void OnCanvasPrePaint(NCanvasPaintEventArgs args)
{
NCanvas canvas = args.TargetNode as NCanvas;
if (canvas == null)
{
return;
}
PaintPrimitiveDelegate paintDelegate = canvas.Tag as PaintPrimitiveDelegate;
if (paintDelegate == null)
{
throw new Exception("The canvas has no assigned paint delegate.");
}
// Clear all styles and set the shadow
args.PaintVisitor.ClearStyles();
args.PaintVisitor.SetShadow(m_Shadow);
// Paint the scene for the current canvas
paintDelegate(args.PaintVisitor, canvas.Width, canvas.Height);
// Paint a bounding rectangle for the canvas
args.PaintVisitor.ClearStyles();
args.PaintVisitor.SetStroke(NColor.Red, 1);
args.PaintVisitor.PaintRectangle(0, 0, canvas.Width, canvas.Height);
}
protected override NWidget CreateExampleContent()
{
m_Shadow = new NShadow(new NColor(160, 160, 160), 20, 20);
string[] names = new string[]
{
"Line", "Polyline", "Rectangle", "Ellipse", "Triangle", "Quad", "Polygon", "Graphics Path"
};
PaintPrimitiveDelegate[] delegates = new PaintPrimitiveDelegate[]
{
new PaintPrimitiveDelegate(PaintLine),
new PaintPrimitiveDelegate(PaintPolyline),
new PaintPrimitiveDelegate(PaintRectangle),
new PaintPrimitiveDelegate(PaintEllipse),
new PaintPrimitiveDelegate(PaintTriangle),
new PaintPrimitiveDelegate(PaintQuadrangle),
new PaintPrimitiveDelegate(PaintPolygon),
new PaintPrimitiveDelegate(PaintPath),
};
int count = delegates.Length;
// Create a table panel to hold the canvases and the labels
m_Table = new NTableFlowPanel();
m_Table.HorizontalPlacement = ENHorizontalPlacement.Left;
m_Table.VerticalPlacement = ENVerticalPlacement.Top;
m_Table.Padding = new NMargins(30);
m_Table.HorizontalSpacing = 30;
m_Table.VerticalSpacing = 30;
m_Table.MaxOrdinal = 4;
for (int i = 0; i < count; i++)
{
NStackPanel stack = new NStackPanel();
m_Table.Add(stack);
stack.VerticalSpacing = 5;
// Create a canvas to draw in
NCanvas canvas = new NCanvas();
canvas.PreferredSize = new NSize(defaultCanvasWidth, defaultCanvasHeight);
canvas.Tag = delegates[i];
canvas.BackgroundFill = new NColorFill(NColor.White);
canvas.PrePaint += new Function <NCanvasPaintEventArgs>(OnCanvasPrePaint);
stack.Add(canvas);
// Create a label for the geometry primitive's name
NLabel label = new NLabel(names[i]);
label.HorizontalPlacement = ENHorizontalPlacement.Center;
stack.Add(label);
}
// The table must be scrollable
NScrollContent scroll = new NScrollContent();
scroll.Content = m_Table;
return(scroll);
}
private void OnCanvasPrePaint(NCanvasPaintEventArgs args)
{
NCanvas canvas = args.TargetNode as NCanvas;
if (canvas == null)
{
return;
}
PaintPrimitiveDelegate paintDelegate = canvas.Tag as PaintPrimitiveDelegate;
if (paintDelegate == null)
{
throw new Exception("The canvas has no assigned paint delegate.");
}
args.PaintVisitor.ClearStyles();
args.PaintVisitor.SetStroke(m_Stroke);
args.PaintVisitor.SetFill(Fill);
paintDelegate(args.PaintVisitor, canvas.Width, canvas.Height);
}
