TList

Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME

Tk::TList - Create and manipulate Tix Tabular List widgets

SYNOPSIS

$tlist = $parent->TList(?options?);

SUPER-CLASS

None.

STANDARD OPTIONS

-background    -borderwidth    -class  -cursor -foreground
-font   -height -highlightcolor -highlightthickness
-relief -selectbackground       -selectforeground
-xscrollcommand -yscrollcommand -width

See Tk::options for details of the standard options.

WIDGET-SPECIFIC OPTIONS

Name: browsecmd
Class: BrowseCmd
Switch: -browsecmd: Specifies a perl/Tk callback to be executed when the user browses through the entries in the TList widget.
Name: command
Class: Command
Switch: -command: Specifies the perl/Tk callback to be executed when the user invokes a list entry in the TList widget. Normally the user invokes a list entry by double-clicking it or pressing the Return key.
Name: foreground
Class: Foreground
Switch: -foreground
Alias: -fg: Specifies the default foreground color for the list entries.
Name: height
Class: Height
Switch: -height: Specifies the desired height for the window in number of characters.
Name: itemType
Class: ItemType
Switch: -itemtype: Specifies the default type of display item for this TList widget. When you call the insert methods, display items of this type will be created if the -itemtype option is not specified.
Name: orient
Class: Orient
Switch: -orient: Specifies the order of tabularizing the list entries. When set to "vertical``, the entries are arranged in a column, from top to bottom. If the entries cannot be contained in one column, the remaining entries will go to the next column, and so on. When set to ''horizontal", the entries are arranged in a row, from left to right. If the entries cannot be contained in one row, the remaining entries will go to the next row, and so on.
Name: padX
Class: Pad
Switch: -padx: The default horizontal padding for list entries.
Name: padY
Class: Pad
Switch: -padx: The default vertical padding for list entries.
Name: selectBackground
Class: SelectBackground
Switch: -selectbackground: Specifies the background color for the selected list entries.
Name: selectBorderWidth
Class: BorderWidth
Switch: -selectborderwidth: Specifies a non-negative value indicating the width of the 3-D border to draw around selected items. The value may have any of the forms acceptable to Tk_GetPixels.
Name: selectForeground
Class: SelectForeground
Switch: -selectforeground: Specifies the foreground color for the selected list entries.
Name: selectMode
Class: SelectMode
Switch: -selectmode: Specifies one of several styles for manipulating the selection. The value of the option may be arbitrary, but the default bindings expect it to be either single, browse, multiple, or extended; the default value is single.
Name: sizeCmd
Class: SizeCmd
Switch: -sizecmd: Specifies a perl/Tk callback to be called whenever the TList widget changes its size. This command can be useful to implement ``user scroll bars when needed'' features.
Name: state
Class: State
Switch: -state: Specifies whether the TList command should react to user actions. When set to "normal``, the TList reacts to user actions in the normal way. When set to ''disabled", the TList can only be scrolled, but its entries cannot be selected or activated.
Name: width
Class: Width
Switch: -width: Specifies the desired width for the window in characters.

DESCRIPTION

The TList method creates a new window (given by the $widget argument) and makes it into a TList widget. Additional options, described above, may be specified on the command line or in the option database to configure aspects of the TList widget such as its cursor and relief.

The TList widget can be used to display data in a tabular format. The list entries of a TList widget are similar to the entries in the Tk listbox widget. The main differences are (1) the TList widget can display the list entries in a two dimensional format and (2) you can use graphical images as well as multiple colors and fonts for the list entries.

Each list entry is identified by an index, which can be in the following forms:

number: An integer that indicates the position of the entry in the list. 0 means the first position, 1 means the second position, and so on.
end: Indicates the end of the listbox. For some commands this means just after the last entry; for other commands it means the last entry.
@x,y: Indicates the element that covers the point in the listbox window specified by x and y (in pixel coordinates). If no element covers that point, then the closest element to that point is used.

DISPLAY ITEMS

Each list entry in an TList widget is associated with a display item. The display item determines what visual information should be displayed for this list entry. Please see Tk::DItem for a list of all display items.

When a list entry is created by the insert command, the type of its display item is determined by the -itemtype option passed to these commands. If the -itemtype is omitted, then by default the type specified by this TList widget's -itemtype option is used.

WIDGET METHODS

The TList 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 TList widgets:

$tlist->anchorSet(index)

Sets the anchor to the list entry identified by index. The anchor is the end of the selection that is fixed while dragging out a selection with the mouse.

$tlist->anchorClear

Removes the anchor, if any, from this TList widget. This only removes the surrounding highlights of the anchor entry and does not affect its selection status.

$tlist->delete(from, ?to?)

Deletes one or more list entries between the two entries specified by the indices from and to. If to is not specified, deletes the single entry specified by from.

$tlist->dragsiteSet(index)

Sets the dragsite to the list entry identified by index. The dragsite is used to indicate the source of a drag-and-drop action. Currently drag-and-drop functionality has not been implemented in Tix yet.

$tlist->dragsiteClear

Remove the dragsite, if any, from the this TList widget. This only removes the surrounding highlights of the dragsite entry and does not affect its selection status.

$tlist->dropsiteSet(index)

Sets the dropsite to the list entry identified by index. The dropsite is used to indicate the target of a drag-and-drop action. Currently drag-and-drop functionality has not been implemented in Tix yet.

$tlist->dropsiteClear

Remove the dropsite, if any, from the this TList widget. This only removes the surrounding highlights of the dropsite entry and does not affect its selection status.

$tlist->entrycget(index, option)

Returns the current value of the configuration option given by option for the entry indentfied by index. Option may have any of the values accepted by the insert method.

$tlist->entryconfigure(index, ?option?, ?value, option, value, ...?)

Query or modify the configuration options of the list entry identified by index. If no option is specified, returns a list describing all of the available options for index (see Tk_ConfigureInfo for information on the format of this list). If option is specified with no value, then the method returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given option(s) to have the given value(s); in this case the method returns an empty string. Option may have any of the values accepted by the insert method. The exact set of options depends on the value of the -itemtype option passed to the the insert method when this list entry is created.

$tlist->insert(index, ?option, value, ...?)

Creates a new list entry at the position indicated by index. The following configuration options can be given to configure the list entry:

-itemtype => type: Specifies the type of display item to be display for the new list entry. type must be a valid display item type. Currently the available display item types are image, imagetext, text, and $widget. If this option is not specified, then by default the type specified by this TList widget's -itemtype option is used.
-state => state: Specifies whether this entry can be selected or invoked by the user. Must be either normal or disabled.
-data => data: Arbitrary data to be associated with the entry (a perl scalar value).

: The insert method accepts additional configuration options to configure the display item associated with this list entry. The set of additional configuration options depends on the type of the display item given by the -itemtype option. Please see Tk::DItem for a list of the configuration options for each of the display item types.

$tlist->info(option, arg, ...)

Query information about the TList widget. option can be one of the following:

$tlist->info(anchor, index): Returns the index of the current anchor, if any, of the TList widget. If the anchor is not set, returns the empty string.
$tlist->info(dragsite, index): Returns the index of the current dragsite, if any, of the TList widget. If the dragsite is not set, returns the empty string.
$tlist->info(dropsite, index): Returns the index of the current dropsite, if any, of the TList widget. If the dropsite is not set, returns the empty string.
$tlist->info(selection): Returns a list of selected elements in the TList widget. If no entries are selected, returns an empty string.

$tlist->nearest(x, y)

Given an (x,y) coordinate within the TList window, this command returns the index of the TList element nearest to that coordinate.

$tlist->see(index)

Adjust the view in the TList so that the entry given by index is visible. If the entry is already visible then the command has no effect; otherwise TList scrolls to bring the element into view at the edge to which it is nearest.

$tlist->selection(option, arg, ...)

This command is used to adjust the selection within a TList widget. It has several forms, depending on option:

$tlist->selectionClear(?from?, ?to?): When no extra arguments are given, deselects all of the list entrie(s) in this TList widget. When only from is given, only the list entry identified by from is deselected. When both from and to are given, deselects all of the list entrie(s) between between from and to, inclusive, without affecting the selection state of entries outside that range.
$tlist->selectionIncludes(index): Returns 1 if the list entry indicated by index is currently selected; returns 0 otherwise.
$tlist->selectionSet(from, ?to?): Selects all of the list entrie(s) between between from and to, inclusive, without affecting the selection state of entries outside that range. When only from is given, only the list entry identified by from is selected.

$tlist->xview(args)

This command is used to query and change the horizontal position of the information in the widget's window. It can take any of the following forms:

$tlist->xview: Returns a list containing two elements. Each element is a real fraction between 0 and 1; together they describe the horizontal span that is visible in the window. For example, if the first element is 0.2 and the second element is 0.6, 20% of the TList entry is off-screen to the left, the middle 40% is visible in the window, and 40% of the entry is off-screen to the right. These are the same values passed to scrollbars via the -xscrollcommand option.
$tlist->xview(index): Adjusts the view in the window so that the list entry identified by index is aligned to the left edge of the window.
$tlist->xviewMoveto(fraction): Adjusts the view in the window so that fraction of the total width of the TList is off-screen to the left. fraction must be a fraction between 0 and 1.
$tlist->xviewScroll(number, what): This command shifts the view in the window left or right according to number and what. Number must be an integer. What must be either units or pages or an abbreviation of one of these. If what is units, the view adjusts left or right by number character units (the width of the 0 character) on the display; if it is pages then the view adjusts by number screenfuls. If number is negative then characters farther to the left become visible; if it is positive then characters farther to the right become visible.

$tlist->yview(?args?)

This command is used to query and change the vertical position of the entries in the widget's window. It can take any of the following forms:

$tlist->yview: Returns a list containing two elements, both of which are real fractions between 0 and 1. The first element gives the position of the list element at the top of the window, relative to the TList as a whole (0.5 means it is halfway through the TList, for example). The second element gives the position of the list entry just after the last one in the window, relative to the TList as a whole. These are the same values passed to scrollbars via the -yscrollcommand option.
$tlist->yview(index): Adjusts the view in the window so that the list entry given by index is displayed at the top of the window.
$tlist->yviewMoveto(fraction): Adjusts the view in the window so that the list entry given by fraction appears at the top of the window. Fraction is a fraction between 0 and 1; 0 indicates the first entry in the TList, 0.33 indicates the entry one-third the way through the TList, and so on.
$tlist->yviewScroll(number, what): This command adjust the view in the window up or down according to number and what. Number must be an integer. What must be either units or pages. If what is units, the view adjusts up or down by number lines; if it is pages then the view adjusts by number screenfuls. If number is negative then earlier entries become visible; if it is positive then later entries become visible.

BINDINGS

[1]: If the -selectmode is ``browse'', when the user drags the mouse pointer over the list entries, the entry under the pointer will be highlighted and the -browsecmd procedure will be called with one parameter, the index of the highlighted entry. Only one entry can be highlighted at a time. The -command procedure will be called when the user double-clicks on a list entry.
[2]: If the -selectmode is ``single'', the entries will only be highlighted by mouse <ButtonRelease-1> events. When a new list entry is highlighted, the -browsecmd procedure will be called with one parameter indicating the highlighted list entry. The -command procedure will be called when the user double-clicks on a list entry.
[3]: If the -selectmode is ``multiple'', when the user drags the mouse pointer over the list entries, all the entries under the pointer will be highlighted. However, only a contiguous region of list entries can be selected. When the highlighted area is changed, the -browsecmd procedure will be called with an undefined parameter. It is the responsibility of the -browsecmd procedure to find out the exact highlighted selection in the TList. The -command procedure will be called when the user double-clicks on a list entry.
[4]: If the -selectmode is ``extended'', when the user drags the mouse pointer over the list entries, all the entries under the pointer will be highlighted. The user can also make disjointed selections using <Control-ButtonPress-1>. When the highlighted area is changed, the -browsecmd procedure will be called with an undefined parameter. It is the responsibility of the -browsecmd procedure to find out the exact highlighted selection in the TList. The -command procedure will be called when the user double-clicks on a list entry.

EXAMPLE

This example demonstrates how to use an TList to store a list of numbers:

    use strict;
    use Tk ();
    use Tk::TList;

    my $mw = Tk::MainWindow->new();
    my $image = $mw->Getimage('folder');
    my $tlist = $mw->TList(-orient => 'vertical');
    for my $text ( qw/one two three four five six seven eight nine/ ) {
        $tlist->insert('end',
                 -itemtype=>'imagetext', -image=>$image, -text=>$text);
    }

    $tlist->pack(-expand=>'yes', -fill=>'both');

    Tk::MainLoop;

KEYWORDS

Tix(n), Tabular Listbox, Display Items