On this type of diagram, symbols can be arranged into a tree for instance:
When a node being drawn or pasted can be attached to a tree, a + sign is shown within the region for the symbol:
As the symbol is moved beneath a potential parent, a tree anchorage indication appears. The symbol can be moved when you move the mouse cursor far enough away from this location. The plus indicator remains near the mouse cursor:
This indicates that the node will be inserted between two others:
If you release the mouse button then the tree is adjusted and you are prompted for the name if this is the action of creating a new symbol:
Pressing Escape to Cancel will remove the node and return the tree to the prior state.
If you drag a node that has children then the children will also be dragged:
In System Architect, moving a hierarchical node which contains another node will switch to normal node movement behavior, thus the node cannot be inserted into the tree. This happens if the preferences option for moving embedded symbols is ticked.
In System Architect XT, the embedded symbols are ignored when moving a containing node.
Keyboard interface
The keyboard interface is slightly different on these diagrams.
Hold down Shift while using the cursor keys to move the cursor.
When a tree node has been selected, the cursor keys, without holding down Shift, will change the selected node:
•Left and right will change selection to the sibling that is next in position to the left and right, respectively.
•Up and down will change selection to the parent and subordinate respectively.
Representationally Consistent diagrams
These are diagrams where the structure in terms of what node symbols are connected and how, and sometimes how node symbols contain others, is recorded in the underlying definitions. Therefore, changing the diagrams can change those definitions.
Attaching a node to a parent adds a reference from the child node to the parent.
On representationally consistent diagrams supporting box-in-box and hierarchical behavior, removal of a node by using a Delete action and then choosing Remove will not clear the parent reference. In System Architect, to delete and update the reference, use the Edit > Cut (or Ctrl+X) command, or drag the node to detach it from its parent. In System Architect XT, you must edit the references directly or use symbol movement to effect the change prior to deleting the symbol.
Adding duplicate nodes will only move them into the tree where there is not a symbol representing the same definition already parented under that node.
