Smart mindmap like autolayout

[Robert]

Hi,

I am looking at implementing a automatic mindmap diagram layout in order to enforce the position of the items dropped as well as update the layout whenever a branch is expanded or collapsed. The basic behavior I am looking for is similar to the one provided as a sample with the mindmap layout sample. One of the tricky part is to update the existing item's position when the user expands a node in order to avoid items overlap. Do you recommand a particular approach in this area. XMind does a pretty good job in this area and this is the kind of behavior I am trying to implement.

Rgds

Robert

[Petar Mladenov]

Hello Robert,

 Usually in order to avoid overlapping, invoking the Layout method should be enough. On Expand/Collapse, if it is performed in the ViewModel, you can throw an event , for instance ExpandCollapsePerformed, the view can listen to a ViewModel's events and simply invoke the Layout function in  the event handlers. Actually similar approach is implemented in our OrgChart demo.

this.viewModel.ChildrenIsExpandedChanged += this.OnViewModelChildrenExpandedOrCollapsed;

private void OnViewModelChildrenExpandedOrCollapsed(object sender, TeamExpandCollapseChangeEventArgs e)
        {
            if (this.viewModel.ShouldLayoutAfterExpandCollapse)
            {
                this.UpdateViewPortWhenTeamVisualChange(e.Team, true);
            }
            this.navigationPane.RefreshThumbnail();
        }

private void UpdateViewPortWhenTeamVisualChange(OrgTeamViewModel team, bool isLayoutSynchronous)
      {
          Point oldPosition = team.Position;
          this.LayoutOrgChart(false, isLayoutSynchronous);
          this.diagram.UpdateViewportRespectingShape(oldPosition, team.Position);
      }

Regards,
Petar Mladenov
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