Hollow Link

GoDiagram (6 and previous)
1

Hi,

I would like to know how to create a diagram in which the link line is hollow. Meaning that the line connecting two nodes will have, say a black outer line and red interior fill.



Something like this:



this is black=> -------------------------

| This is red |

this is black=> -------------------------/



I can do it by setting the following:



PenColor = Color.Red;

PenWidth = 2;

HighlightPenColor = Color.Black;

HighlightPenWidth = 3;

Highlight = true;



but then I cannot give the user feedback when the link is selected.



Thank you,

Ido.

2

If you haven’t set HighlightWhenSelected, you should be getting selection handles.

3

you could create a Golink Class that has these overrides.

This allows you to use Highlight in the design of the link, yet still have color for selection.
[code]
public override void AddSelectionHandles(GoSelection sel, GoObject selectedObj) {
bool oldskips = this.SkipsUndoManager;
this.SkipsUndoManager = true;
this.HighlightPenColor = System.Drawing.Color.Chartreuse;
this.SkipsUndoManager = oldskips;
}
public override void RemoveSelectionHandles(GoSelection sel) {
bool oldskips = this.SkipsUndoManager;
this.SkipsUndoManager = true;
this.HighlightPenColor = Color.Black; // whatever color you want the link to be when not selected
this.SkipsUndoManager = oldskips;
}
[/code]
or... if you care about Primary / Secondary selection colors, a more complicated version:
[code]
public override void AddSelectionHandles(GoSelection sel, GoObject selectedObj) {
bool oldskips = this.SkipsUndoManager;
this.SkipsUndoManager = true;
Color selColor = Color.LightGray;
GoView view = sel.View;
if (view != null) {
if (sel.Focused) {
if (sel.Primary != null &&
sel.Primary.SelectionObject == this) {
selColor = view.PrimarySelectionColor;
} else {
selColor = view.SecondarySelectionColor;
}
} else {
selColor = view.NoFocusSelectionColor;
}
}
this.HighlightPenColor = selColor;
this.SkipsUndoManager = oldskips;
}
[/code]
4

Thank Jake, your answer seem to solve it.

The method names are not intuitive.

5

I’m also looking to do something similar, but instead of filling with another color, is it possible to have it transparent? In other words just have an outline of a link?

6

Create a Pen with a CompoundArray, which is a float[] of fractions from 0.0f to 1.0f of alternating pen line color and nothing, and set the GoShape.Pen property.