Link Groups

Link groups define sets of link types. A Link type defines certain properties of a link (see Linking Nodes for more information on links). Compendium comes with a default link group containing the link types for Issue-Based Information Systems (IBIS). Link group data is saved in the form of an xml file for each link group, and these are stored in the Compendium subfolder 'LinkGroups'. You will initially have one file in this folder called 'Default.xml' holding the default IBIS link group information. Each link type in a link group has a universally unique identifier, so you can share your link group files with other if you wish and there will be no clashes.

You can create your own link groups and link types using the Link Groups Management dialog. This can be accessed from the Tools Menu . The initial Link Groups dialog will look something link figure 1 below:

Figure 1. The Link Groups management dialog

Here you can see that there is initially only the IBIS link group. (It appears in italics as it has been set as the active group).

To create a new link group, press the 'Create New Link Group' button at the top of the Link Groups management dialog. This will open the Link Group dialog as in figure 2 below:

Figure 2. The Link Group dialog

You must enter a name for the new link group in the 'Name' field at the top of the dialog. You can then start adding new link types. To add a new link type, press the 'Add Item' button. This will open a 'Link Type' dialog as in figure 3 below:

Figure 3. The Link Type dialog

Here you need to enter the name of the new link type, then any default link label text (optional). You then need to set the colour for the link type. Press the 'Link Colour' button to open the Colour Chooser dialog and select a link colour (see figure 4 below).

Figure 4. The Colour Chooser dialog

When you have completed all these fields, press 'Save' to save the new link type and return to the Link Group dialog. You will see that the new link type has appeared as in figure 5:

Figure 5. The Link Group dialog with new link type added.

If you wish to edit any link type select it and press the 'Edit' button, This will open a Link Type dialog with the existing details for you to edit, as in figure 3 above. If you wish to delete a link type, simply select it from the list and press the 'Delete' button.

NOTE: If you delete a link type and it is a link type which you currently have assigned to links, those links will then display as the default IBIS link colour black, unless you change the link's link type. So please be careful with this delete option.

Once you have added all the link types you desire, you then need to set one of the link types as the default link type for the group. This default link type will then be what is used when you create new links, if this link group is set as the active group. Use the 'Set/Unset Default Link Type' button to do this. The default link type will be displayed in italics. If you press the 'Save' button without designating a default link type, you will be prompted to do do.

Once you press 'Save', the new link group will appear in the Link Groups management dialog:

Figure 6. The Link Groups management dialog with the new link group.

If you wish to edit any link group select it and press the 'Edit' button. This will open a Link Group dialog with the existing details for you to edit. If you wish to delete a link group, simply select it from the list and press the 'Delete' button (if Compendium cannot delete the associated xml file due to the system not allowing it, you will need to manually delete the xml file for the group to be permanently deleted, otherwise it will reappear next time you open Compendium).

NOTE: If you delete link types either directly or by deleting the whole link group, and they are link types which you currently have assigned to links, those links will then display as the default IBIS link colour black, unless you change the link's link type. So please be careful with these delete options.

There is another button on this dialog called 'Duplicate'. This allows you to duplicate a link group, if you wish to create a second link group very similar to an existing one. You will be asked to give a name for the new link group, and then the contents of the selected link group will be copied under the new name.

The finally button to discuss is the 'Set/Unset Active Group' button. You do not have to set an active group. If you select a group and press the button, the group name will appear in italics. This group's link types will then appear on the Link Right-Click Menu for changing link types. It will also be this group's default link type which is used when you create a new link.

If you do not set an active group, the system holds the original default IBIS information which is will use when you create links.
Note: this is not the same as the IBIS group you see in the Link Groups dialog, as you may have edited this groups properties. But the system holds a duplicate of what the default setting for the IBIS group are and if you do not set an active link group, it will use them instead.