Tree(3) User Contributed Perl Documentation Tree(3)NAMETk::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/exam‐
ples/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 con‐
figure and cget methods described in Tk::options which can be used to
enquire and modify the options described above. The widget also inher‐
its all the methods provided by the generic Tk::Widget class.
The following additional methods are available for Tree widgets:
$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->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 entry‐
Path 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 the the entry. If mode is set to close,
a (-) indicator is drawn next the 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.
ACKNOWLEDGEMENTS
Thanks to Achim Bohnet <ach@mpe.mpg.de> for all his help.
perl v5.8.8 2004-02-28 Tree(3)
