Tree Display

Gnus Manual. Node: Tree Display

PREV Alternative Approaches The Summary Buffer NEXT Mail Group Commands

3.22: Tree Display

If you don't like the normal Gnus summary display, you might try setting gnus-use-trees to t. This will create (by default) an additional tree buffer. You can execute all summary mode commands in the tree buffer.

There are a few variables to customize the tree display, of course:

gnus-tree-mode-hook

A hook called in all tree mode buffers.

gnus-tree-mode-line-format

A format string for the mode bar in the tree mode buffers (see Mode Line Formatting). The default is `Gnus: %%b %S %Z'. For a list of valid specs, see Summary Buffer Mode Line.

gnus-selected-tree-face

Face used for highlighting the selected article in the tree buffer. The default is modeline.

gnus-tree-line-format

A format string for the tree nodes. The name is a bit of a misnomer, though---it doesn't define a line, but just the node. The default value is `%(%[%3,3n%]%)', which displays the first three characters of the name of the poster. It is vital that all nodes are of the same length, so you must use `%4,4n'-like specifiers.

Valid specs are:

``n`'	The name of the poster.
``f`'	The `From` header.
``N`'	The number of the article.
``[`'	The opening bracket.
``]`'	The closing bracket.
``s`'	The subject.

See Formatting Variables.

Variables related to the display are:

`gnus-tree-brackets`	This is used for differentiating between ``real'' articles and ``sparse'' articles. The format is `((real-open . real-close) (sparse-open . sparse-close) (dummy-open . dummy-close))`, and the default is `((?[ . ?]) (?( . ?)) (?{ . ?}) (?< . ?>))`.
`gnus-tree-parent-child-edges`	This is a list that contains the characters used for connecting parent nodes to their children. The default is `(?- ?\\ ?\|)`.

gnus-tree-minimize-window

If this variable is non-nil, Gnus will try to keep the tree buffer as small as possible to allow more room for the other Gnus windows. If this variable is a number, the tree buffer will never be higher than that number. The default is t. Note that if you have several windows displayed side-by-side in a frame and the tree buffer is one of these, minimizing the tree window will also resize all other windows displayed next to it.

gnus-generate-tree-function

The function that actually generates the thread tree. Two predefined functions are available: gnus-generate-horizontal-tree and gnus-generate-vertical-tree (which is the default).

Here's an example from a horizontal tree buffer:

{***}-(***)-[odd]-[Gun]
     |      \[Jan]
     |      \[odd]-[Eri]
     |      \(***)-[Eri]
     |            \[odd]-[Paa]
     \[Bjo]
     \[Gun]
     \[Gun]-[Jor]

Here's the same thread displayed in a vertical tree buffer:

{***}
  |--------------------------\-----\-----\
(***)                         [Bjo] [Gun] [Gun]
  |--\-----\-----\                          |
[odd] [Jan] [odd] (***)                   [Jor]
  |           |     |--\
[Gun]       [Eri] [Eri] [odd]
                          |
                        [Paa]

If you're using horizontal trees, it might be nice to display the trees side-by-side with the summary buffer. You could add something like the following to your `.gnus.el' file:

(setq gnus-use-trees t
      gnus-generate-tree-function 'gnus-generate-horizontal-tree
      gnus-tree-minimize-window nil)
(gnus-add-configuration
 '(article
   (vertical 1.0
             (horizontal 0.25
                         (summary 0.75 point)
                         (tree 1.0))
             (article 1.0))))

See Windows Configuration.

Alternative Approaches

The Summary Buffer NEXT

Mail Group Commands