NAME

       Tk::Tree - Create and manipulate Tree widgets

SYNOPSIS

           use Tk::Tree;

           $tree = $parent->Tree(?options?);

SUPER-CLASS

       The Tree class is derived from the HList class and inherits all the methods, options and
       subwidgets of its super-class.  A Tree widget is not scrolled by default.

STANDARD OPTIONS

       Tree supports all the standard options of an HList widget.  See Tk::options for details on
       the standard options.

WIDGET-SPECIFIC OPTIONS

       Name:          browseCmd
       Class:         BrowseCmd
       Switch:        -browsecmd
           Specifies a callback to call whenever the user browses on an entry (usually by single-
           clicking on the entry). The callback is called with one argument, the pathname of the
           entry.

       Name:          closeCmd
       Class:         CloseCmd
       Switch:        -closecmd
           Specifies a callback to call whenever an entry needs to be closed (See "BINDINGS"
           below). This method is called with one argument, the pathname of the entry. This
           method should perform appropriate actions to close the specified entry. If the
           -closecmd option is not specified, the default closing action is to hide all child
           entries of the specified entry.

       Name:          command
       Class:         Command
       Switch:        -command
           Specifies a callback to call whenever the user activates an entry (usually by double-
           clicking on the entry). The callback is called with one argument, the pathname of the
           entry.

       Name:          ignoreInvoke
       Class:         IgnoreInvoke
       Switch:        -ignoreinvoke
           A Boolean value that specifies when a branch should be opened or closed. A branch will
           always be opened or closed when the user presses the (+) and (-) indicators. However,
           when the user invokes a branch (by doublc-clicking or pressing <Return>), the branch
           will be opened or closed only if -ignoreinvoke is set to false (the default setting).

       Name:          openCmd
       Class:         OpenCmd
       Switch:        -opencmd
           Specifies a callback to call whenever an entry needs to be opened (See "BINDINGS"
           below). This method is called with one argument, the pathname of the entry. This
           method should perform appropriate actions to open the specified entry. If the -opencmd
           option is not specified, the default opening action is to show all the child entries
           of the specified entry.

DESCRIPTION

       The Tree method creates a new window and makes it into a Tree widget and return a
       reference to it.  Additional options, described above, may be specified on the command
       line or in the option database to configure aspects of the Tree widget such as its cursor
       and relief.

       The Tree widget can be used to display hierarchical data in a tree form. The user can
       adjust the view of the tree by opening or closing parts of the tree.

       To display a static tree structure, you can add the entries into the Tree widget and hide
       any entries as desired. Then you can call the autosetmode method. This will set up the
       Tree widget so that it handles all the open and close events automatically.  the
       demonstration program Tixish/examples/perl-tix-tree).

       The above method is not applicable if you want to maintain a dynamic tree structure, i.e,
       you do not know all the entries in the tree and you need to add or delete entries
       subsequently. To do this, you should first create the entries in the Tree widget. Then,
       use the setmode method to indicate the entries that can be opened or closed, and use the
       -opencmd and -closecmd options to handle the opening and closing events. (Please see the
       demonstration program Tixish/examples/perl-tix-dyntree).

       Use either

           $parent->Scrolled('Tree', ... );

       or

           $parent->ScrlTree( ... );

       to create a scrolled Tree. See Tk::Scrolled for details.

WIDGET METHODS

       The Tree method creates a widget object.  This object supports the configure and cget
       methods described in Tk::options which can be used to enquire and modify the options
       described above.  The widget also inherits all the methods provided by the generic
       Tk::Widget class.

       The following additional methods are available for Tree widgets:

       $tree->add_pathimage(treeRegExp [, openImg, closeImg])
           This method defines images for a given path (images must be in xpm format). The path
           can be determined by a simplified regular expression. There are just three
           metasymbols:

           ^   at the beginning of the "treeRegExp" same as in Perl regular expressions

           *   anything

           $   at the end of the "TreeRegExp", the same as in Perl regular expressions

           Examples:

             $tree->add_pathimage('^root','openfolder','folder');

           matches "root", "root.foo", "root.bar", but not "foo.root"

             $tree->add_pathimage('root.*.class','openfolder','folder');

           matches all paths containing "root.<anything>.class", but not
           "root.<anything>.<anything>.class" "*" is one part of the path. If you want to use a
           wildcard for two steps, you have to use "*.*".

             $tree->add_pathimage('class$','openfolder','folder');

           This matches all path with "class" at the end.

       $tree->autosetmode
           This method calls the setmode method for all the entries in this Tree widget: if an
           entry has no child entries, its mode is set to none. Otherwise, if the entry has any
           hidden child entries, its mode is set to open; otherwise its mode is set to close.

       $tree->child_entries([$path][,$depth])
           This method returns in list context an array that contains all pathnames of subentries
           within the given path. In scalar context it returns the number of subentries in the
           given path.

             Example:
               root
                | foo
                | bar
                |  | bar1
                |  | bar2

             my @childentries = $tree->child_entries('root.bar');
             # returns (root.bar.bar1, root.bar.bar2)

             my $nr_of_subentries = $tree->child_entries('root',2);
             # returns 4

           If $path is omitted, all it is assumed, that the entry above 'root' is meant. $depth
           defines the numbers of levels.

       $tree->close(entryPath)
           Close the entry given by entryPath if its mode is close.

       $tree->getmode(entryPath)
           Returns the current mode of the entry given by entryPath.

       $tree->open(entryPath)
           Open the entry given by entryPath if its mode is open.

       $tree->setmode(entryPath, mode)
           This method is used to indicate whether the entry given by entryPath has children
           entries and whether the children are visible. mode must be one of open, close or none.
           If mode is set to open, a (+) indicator is drawn next to the entry. If mode is set to
           close, a (-) indicator is drawn next to the entry. If mode is set to none, no
           indicators will be drawn for this entry. The default mode is none. The open mode
           indicates the entry has hidden children and this entry can be opened by the user. The
           close mode indicates that all the children of the entry are now visible and the entry
           can be closed by the user.

BINDINGS

       The basic mouse and keyboard bindings of the Tree widget are the same as the bindings of
       the HList widget.  In addition, the entries can be opened or closed under the following
       conditions:

       [1] If the mode of the entry is open, it can be opened by clicking on its (+) indicator.

       [2] If the mode of the entry is close, it can be closed by clicking on its (-) indicator.

SEE ALSO

       Tk::HList

AUTHOR

       Perl/TK version by Chris Dean <ctdean@cogit.com>.  Original Tcl/Tix version by Ioi Kim
       Lam.

       Additions by Renee Baecker <module@renee-baecker.de>

ACKNOWLEDGEMENTS

       Thanks to Achim Bohnet <ach@mpe.mpg.de> for all his help.

POD ERRORS

       Hey! The above document had some coding errors, which are explained below:

       Around line 153:
           Expected text after =item, not a bullet