TreeLayout - how to wrap trees

GoXam
#1

Hi, i am using release 1.2.3.4.
i have a TreeLayout containing too many small tree to either arrange only vertical or horizontal.
i want to be able arrange them vertically but to wrap them into multiple columns.
any help would appreciated.

BTW its been a while since my last visit here, i am glad to see its still very much alive and kicking Wink
Thanks, Aviv and the BMC team.

#2

You need to override TreeLayout.ArrangeTrees.

Rather than try to explain how you should do it, here’s the definition, so you can see how the normal TreeArrangement choices are implemented:

[code] protected virtual void ArrangeTrees() {
if (this.Arrangement == TreeArrangement.FixedRoots) {
foreach (Node r in this.Roots) {
TreeVertex root = this.Network.FindVertex®;
Rect b = r.Bounds;
if (Double.IsNaN(b.X) || Double.IsInfinity(b.X)) b.X = 0;
if (Double.IsNaN(b.Y) || Double.IsInfinity(b.Y)) b.Y = 0;
AssignAbsolutePositions(root, new Point(b.X, b.Y));
}
} else {
Point p = this.ArrangementOrigin;
foreach (Node r in this.Roots) {
TreeVertex root = this.Network.FindVertex®;
if (root == null) continue;
Point q = p;
q.X += root.SubtreeOffset.X;
q.Y += root.SubtreeOffset.Y;
AssignAbsolutePositions(root, q);
switch (this.Arrangement) {
case TreeArrangement.Vertical:
p.Y += root.SubtreeSize.Height + this.ArrangementSpacing.Height;
break;
case TreeArrangement.Horizontal:
p.X += root.SubtreeSize.Width + this.ArrangementSpacing.Width;
break;
default:
throw new InvalidOperationException("Unhandled Arrangement value " + this.Arrangement.ToString());
}
}
}
}

internal void AssignAbsolutePositions(TreeVertex v, Point p) {
  if (v == null) return;
  v.Position = p;
  foreach (TreeVertex c in v.Children) {
    AssignAbsolutePositions(c, new Point(p.X + c.RelativePosition.X, p.Y + c.RelativePosition.Y));
  }
}[/code]

I do recommend upgrading to version 1.3.*. We should be coming out with another baselevel (1.3.6) shortly.

#3

Thanks!
here is my new layout in case someone needs it :

public class VerticalWrapTreeLayout : TreeLayout
{
#region NumberOfColumns (DependencyProperty)

    public int NumberOfColumns
    {
        get { return (int)GetValue(NumberOfColumnsProperty); }
        set { SetValue(NumberOfColumnsProperty, value); }
    }
    public static readonly DependencyProperty NumberOfColumnsProperty =
        DependencyProperty.Register(
            "NumberOfColumns",
            typeof(int),
            typeof(VerticalWrapTreeLayout),
            new PropertyMetadata(5)
            );

    #endregion

    protected override void ArrangeTrees()
    {
        var p = ArrangementOrigin;
        int nodesPerColumn = Roots.Count < NumberOfColumns ? Roots.Count : Roots.Count / NumberOfColumns;//we want 5 columns
        var counter = 0;
        var maxTreeWidth = 0.0;
        foreach (var r in Roots)
        {
            counter++;
            var root = Network.FindVertex(r);
            if (root == null) continue;
            var q = p;
            q.X += root.SubtreeOffset.X;
            q.Y += root.SubtreeOffset.Y;
            AssignAbsolutePositions(root, q);
            if (root.SubtreeSize.Width > maxTreeWidth) maxTreeWidth = root.SubtreeSize.Width;//maintain max tree width within column
            if (counter % nodesPerColumn == 0)//move start point to next column
            {
                p.X += maxTreeWidth + ArrangementSpacing.Width;//move x to the left as much as the widest tree in the column
                p.Y = ArrangementOrigin.Y;//move y up the the start point
                maxTreeWidth = 0.0;//new column max will start fresh
            }
            else
            {
                p.Y += root.SubtreeSize.Height + ArrangementSpacing.Height;//next node moves down
            }
        }
    }

    internal void AssignAbsolutePositions(TreeVertex v, Point p)
    {
        if (v == null) return;
        v.Position = p;
        foreach (var c in v.Children)
        {
            AssignAbsolutePositions(c, new Point(p.X + c.RelativePosition.X, p.Y + c.RelativePosition.Y));
        }
    }
}