18.104.22.168 Basic knowledge about the styles
There are nine image-names which define the control- and guide-symbols
to draw the tree. Here is the list of the allowed image-names and the
related corresponding ascii-symbols:
- open (“[-]”):
The control-symbol displayed for an opened tree-node which has several
subnodes. Clicking onto this control closes the node.
- close (“[+]”):
The control-symbol displayed for a closed tree-node, i.e. an
expandable node with subnodes but all subnodes are hidden. Clicking
onto this control opened the node and displays its subnodes - if
there are any. If it has no subnodes the empty-symbol will be
- empty (“[x]”):
The symbol displayed for an empty node. An empty node is a
node which could have subnodes but has currently none.
- leaf (“*”):
The symbol displayed for a node which can not have any subnodes so it
is a “leaf” in the tree.
- guide (“ |”):
The symbol used for drawing vertical “guide-lines” for opened nodes.
See the example below.
- no-guide (“ ”):
Sometimes invisible guide-lines are needed to draw the tree.
- end-guide (“ `”):
The symbol used for the guide-line of the last subnode of an opened
- handle (“-”):
The symbol displayed before every subnode. Each handle is connected to
a guide-line - either a normal guide or an end-guide.
- no-handle (“ ”):
An invisible handle.
A tree will be build-up with these elements like follows:
[-] node-with-subnodes (open)
|-[+] not-empty-subnode1 (guide+handle+close)
|-[x] empty-subnode (guide+handle+empty)
`-[-] not-empty-subnode2 (end-guide+handle+open)
|-* leaf-1 (no-guide+no-handle+guide+handle+leaf)
`-* leaf-2 (no-guide+no-handle+end-guide+handle+leaf)