Move Label of GoSimpleNode freely

GoDiagram (6 and previous)
1

I want to move the label of GoSimpleNode to any position. I have read that there is a constraint that enforced in setting GoObject.Bound or GoGroup.LayoutChildren. Can I disallow this constraints??

2

GoIconicNode has a “DraggableLabel” property that you can set to true.

Check the “Processor” sample for a use of that.

It may be easier to emulate a GoSimpleNode with the Processor node and ports than to add
draggable labels to GoSimpleNode.

3

ok… I haven’t spent a lot of time on this, but here is the DraggableLabel code from GoIconicNode pasted into a GoSimpleNode override.

[Serializable]
public class GoSimpleNodeWithDraggableLabel : GoSimpleNode
{
protected override GoText CreateLabel(string name) {
GoText l = base.CreateLabel(name);
l.Selectable = this.DraggableLabel;
return l;
}

public override void LayoutChildren(GoObject childchanged) {
  if (this.Initializing) return;

  GoObject icon = this.Icon;
  if (icon == null) return;

  if (this.Orientation == Orientation.Horizontal) {
    if (this.InPort != null)
      this.InPort.SetSpotLocation(MiddleRight, icon, MiddleLeft);
    if (this.OutPort != null)
      this.OutPort.SetSpotLocation(MiddleLeft, icon, MiddleRight);
  }
  else {
    if (this.InPort != null)
      this.InPort.SetSpotLocation(MiddleBottom, icon, MiddleTop);
    if (this.OutPort != null)
      this.OutPort.SetSpotLocation(MiddleTop, icon, MiddleBottom);
  }

  GoText label = this.Label;
  if (label != null) {
    // if DraggableLabel is true, let the user drag it around without moving
    // any other children of this node
    if (this.DraggableLabel && childchanged == label) {
      // remember where the label now is relative to the icon
      myLabelOffset = new SizeF(label.Left - icon.Left, label.Top - icon.Top);
      return;  // don't position port or anything else
    }
    else if (myLabelOffset.Width > -99999) {  // place it relative to the icon
      label.Position = new PointF(icon.Left + myLabelOffset.Width, icon.Top + myLabelOffset.Height);
    }
    else {  // put the label below the icon
      label.SetSpotLocation(MiddleTop, icon, MiddleBottom);
    }
  }
}

/// <summary>
/// Gets or sets whether the user can drag the label around independently of the node.
/// </summary>
/// <value>
/// Initially this value is false--the label is always positioned by
/// <see cref="LayoutChildren"/> and users cannot move the
/// label without moving the whole node.
/// </value>
public virtual bool DraggableLabel {
  get { return myDraggableLabel; }
  set {
    bool old = myDraggableLabel;
    if (old != value) {
      myDraggableLabel = value;
      Changed(ChangedDraggableLabel, 0, old, NullRect, 0, value, NullRect);
      if (!this.Initializing && this.Label != null)
        this.Label.Selectable = value;
    }
  }
}

/// <summary>
/// Gets or sets the relative position of the <see cref="Label"/>'s position
/// compared to the <see cref="Icon"/>'s position.
/// </summary>
/// <value>
/// A very large negative offset causes <see cref="LayoutChildren"/> to
/// ignore this value, resulting in the <see cref="Label"/> being
/// placed underneath the <see cref="Icon"/>.
/// </value>
/// <remarks>
/// This is automatically updated if the <see cref="DraggableLabel"/> is 
/// true and the user drags the label around.
/// </remarks>
public virtual SizeF LabelOffset {
  get { return myLabelOffset; }
  set {
    SizeF old = myLabelOffset;
    if (old != value) {
      myLabelOffset = value;
      Changed(ChangedLabelOffset, 0, null, MakeRect(old), 0, null, MakeRect(value));
      if (!this.Initializing) {
        LayoutChildren(null);
      }
    }
  }
}

public override void ChangeValue(GoChangedEventArgs e, bool undo) {
  switch (e.SubHint) {
    case ChangedDraggableLabel:
      this.DraggableLabel = (bool)e.GetValue(undo);
      return;
     default:
      base.ChangeValue(e, undo);
      return;
  }
}

public const int ChangedDraggableLabel = 2651;
public const int ChangedLabelOffset = 2655;

private bool myDraggableLabel = false;
private SizeF myLabelOffset = new SizeF(-99999, -99999);  // used when Width > -99999

}