Jim Turner
and 1 contributors

NAME

Tk::HMListbox - Sortable Multicolumn HListbox (allowing icons, along with text) with arrows in headers indicating sort order.

AUTHOR

Jim Turner

(c) 2015-2019, Jim Turner under the same license that Perl 5 itself is. All rights reserved.

Tk::SMListbox author: me

Tk::HListbox author: me

Tk::MListbox authors: Hans Jorgen Helgesen, hans_helgesen@hotmail.com (from March 2000: hans.helgesen@novit.no)

SYNOPSIS

use Tk::HMListbox;

$hml = $parent->HMListbox (<options>);

DESCRIPTION

Tk::HMListbox is a derivitive of my Tk::SMListbox (and thus Tk::MListbox that uses Tk::HListbox (instead of Tk::Listbox, as used by the latter two) which was done to allow for image icons to be included in columns along with the traditional text strings. I created both of these Tk::H*Listbox widgets in order to include a column of tiny file-type icons, in addition to the other file attribute columns in my JFM4 Perl/Tk-based file-manager application. Tk::HMListbox is designed to work as a drop-in replacement for either Tk::SMListbox or Tk::MListbox, maintaining backward-compatability with both.

Sorting is done by clicking on one of the column headings in the widget. The first click will sort the data with the selected column as key, a new click will reverse the sort order.

EXAMPLES

my $table = $w->Scrolled('HMListbox'

        -scrollbars => 'se', 

        -height => 12,

        -relief => 'sunken',

        -sortable => 1,   #USER CAN SORT BY COLUMN BY CLICKING ON THE COLUMN HEADER BUTTON.

        -selectmode => 'extended',

        -showallsortcolumns => 1,  #SHOW SORT DIRECTION ARROW ON ALL SORTED COLUMNS.

        -takefocus => 1,

        -borderwidth => 1,

        -fillcolumn => 1,   #IF WINDOW RESIZED, EXPAND COLUMN 1 ("Name") TO FILL THE EXTRA SPACE.

        -columns => [    #COLUMN WIDTH, SORT FUNCTIONS, HEADER BUTTON INFORMATION, ETC.:

            [-itemtype => 'imagetext', -text => '~D', -width => 4, 
                -comparecmd => sub { $_[0]->{'-sort'} cmp $_[1]->{'-sort'} } ],

            [-text => '~Name', -width => 25 ],

            [-text => '~Perm.', -width => 10 ],

            [-text => '~Owner:Group', -width => 14 ],

            [-text => '~Size', -width => 8 ],

            [-text => 'Date/~Time', -width => 15, -reversearrow => 1, -comparecommand => sub { $_[1] cmp $_[0] }],

        ]

        )->pack(

                -expand => 'yes',

        );

STANDARD OPTIONS

-background -foreground -relief -takefocus -borderwidth -heigh -selectbackground -cursor -highlightbackground -selectborderwidth -xscrollcommand -exportselection -highlightcolor -selectforeground -yscrollcommand -font -highlightthickness -setgrid

WIDGET SPECIFIC OPTIONS

-columns => list

Defines the columns in the widget. Each element in the list describes a column. See the COLUMNS section below.

-configurecommand => callback

The -configurecommand callback will be called whenever the layout of the widget has changed due to user interaction. That is, the user changes the width of a column by dragging the separator, or moves a column by dragging the column header.

This option is useful if the application wants to store the widget layout for later retrieval. The widget layout can be obtained by the callback by calling the method columnPackInfo().

-fillcolumn => index

Specify the index number of a column that will expand to fill any new space opened up by dragging the window to a larger size. All other columns maintain their current widths unless changed by the user dragging a column separator. Otherwise all columns maintain their sizes and the extra space is unused (if no column specified here). Default: -1 (no column expands horizontally). All columns always expand vertically though. The same column keeps it's expansion privilege even if user rearranges their positions.

-focuscolumn => index

DEPRECIATED: Sets the index of the column whose listbox is to receive the keyboard focus when the HMListbox widget receives keyboard focus. This is a holdover from Tk::SMListbox, where it is useful to better display the active element cursor due to the fact that it depends on Tk::Listbox, which does not display the active element (usually underlined) unless the listbox itself has the focus. This allows the programmer to specify a colum other than the first one, ie, if the main column of interest to the user is not the first one.

Tk::HMListbox depends instead on Tk::HListbox, which does display the active element without specifically being focused making it unnecessary to designate a specific widget to show the active cursor, so therefore all column listboxes show the active element regardless of which has the focus and Tk::HListbox can assign the first column (the default if this isn't specified here) the focus and everything displays properly.

NOTE: none of this applies if -nocolumnfocus is set, which also has the side effect of disabling most keyboard bindings on the HMListbox. Default: 0 (First column listbox gets focus).

-headerbackground => color

Specify a different background color for the top ("header") row. Default: -background or parent window's background.

-headerforeground => color

Specify a different foreground color for the top ("header") row. Default: -foreground or parent window's foreground.

-ipadx => number

Specify horizontal padding style in pixels around the image for the rows in the listbox which are type image or imagetext. Default: 0

-ipady => number

Specify vertical padding style in pixels around the image for the rows in the listbox which are type image or imagetext. This can be useful in correcting vertical misallignment between the columns when some columns contain images and others are text only! NOTE: This changes the height of the affected rows. Default: 1 (and setting to 0 is the same as 1).

-moveable => boolean

A value of 1 indicates that it is okay for the user to move the columns by dragging the column headers. 0 disables this function. Default: 1.

-nocolumnfocus => boolean

Prevents the HMListbox widget from giving the keyboard focus to a specific column. In HMListbox, it doesn't matter which column receives the focus (the default without setting -focuscolumn is that the first column normally gets the focus when the HMListbox widgets receives keyboard focus). The net effect of this option being set is that the widget itself takes focus, but many keyboard bindings will not work, namely selecting rows with the spacebar. Default: 0 (Take focus normally and give the focus to one of the column listboxes under the hood so that row-based keyboard bindings will all work properly). To have the HMListbox widget itself be skipped in the focus order, set -takefocus to 0.

-resizeable => boolean

A value of 1 indicates that it is okay for the user to resize the columns by dragging the column separators. 0 disables this function. Default: 1.

Note that you can also specify -resizeable on a column by column basis. See the COLUMNS section below.

-selectmode => string

Should be "single", "browse", "multiple", or "extended". Default: "browse". See Tk::HListbox.

-separatorcolor => string

Specifies the color of the separator lines (the vertical lines that separates the columns). Default: black.

Note that you can also specify -separatorcolor on a column by column basis. See the COLUMNS section below.

-separatorwidth => integer

Specifies the width in pixels of the separator lines (the vertical lines that separates the columns). Default: 1.

Note that you can also specify -separatorwidth on a column by column basis. See the COLUMNS section below.

-sortable => boolean

A value of 1 indicates that it is okay for the user to sort the data by clicking column headings. 0 disables this function. Default: 1.

Note that you can also specify -sortable on a column by column basis. See COLUMNS below.

-tpadx => number

Specify horizontal padding style in pixels around the text for the rows in the listbox which are type text. Default: 0

-tpady => number

Specify vertical padding style in pixels around the text for the rows in the listbox which are type text. This can be useful in correcting vertical misallignment between the columns when some columns contain images and others are text only! NOTE: This changes the height of the affected rows. Default (seems to be): 2 (and setting to 0 is the same as 2).

WIDGET SPECIFIC, COLUMN-SPECIFIC OPTIONS

-comparecmd => callback

Specifies a callback to use when sorting the HMListbox with this column as key. The callback will be called with two scalar arguments, each a value from this particular column. The callback should return an integer less than, equal to, or greater than 0, depending on how the tow arguments are ordered. If for example the column should be sorted by numerical value:

    -comparecommand => sub { $_[0] <=> $_[1]}

Default: sub { $_[0] cmp $_[1] } #(Ascending by string) NOTE: If the column data is images or hashrefs (both text and images or contains additional cell-specific options, then one should specify a component of that hash to sort by, ie. the special "-sort" key is handy, then one can sort using something like:

        sub { $_[0]->{'-sort'} cmp $_[1]->{'-sort'} } or maybe:

        sub { $_[0]->{'-text'} cmp $_[1]->{'-text'} }
-itemtype => "text" | "imagetext"

New option (not included with Tk::SMListbox or Tk::MListbox) that permits a column to contain either images and or text in it's entries. Valid values are "text" and "imagetext". Default: "text".

-reversearrow => 0 | 1

New option (not included with the old Tk::MListbox) that causes the up / down direction of the sort arrow in the column header that shows the direction the sorted-by column is currently sorted. Default: 0 (zero): (Up-arrow) if sorted in ascending order, Down-arrow if in descending order. Setting to 1 reverses this. This is often necessary to show desired results, ie. if the sort function is reversed, such as: sub { $_[1] cmp $_[0] }

HMListbox COLUMN CONFIGURATION

NOTE: See also the additional options described in the previous section "WIDGET SPECIFIC COLUMN-SPECIFIC OPTIONS".

The HMListbox widget is a collection of HMLColumn widgets. Each HMLColumn contains a HListbox, a heading and the separator bar. The columns are created and maintained through the -columns option or the column methods of the widget. The columns are indexed from 0 and up. Initially, column 0 is the leftmost column of the widget. The column indices are not changed when the columns are moved or hidden. The only ways to change the column indices are to call columnInsert(), columnDelete() or configure(-column).

Each column has its own set of options which might be passed to HMListbox::configure(-columns), HMListbox::insert(), HMListbox::columnConfigure() or HMLColumn::configure().

The following code snippets are all equal:

1. my $hml=$mw->HMListbox(-columns=>[[-text=>'Heading1', -sortable=>0], [-text=>'Heading2']]);

2. my $hml=$mw->HMListbox; $hml->columnInsert(0,-text=>'Heading1', -sortable=>0); $hml->columnInsert(0,-text=>'Heading2');

3. my $hml=$mw->HMListbox; $c=$hml->columnInsert(0,-text=>'Heading1'); $hml->columnInsert(0,-text=>'Heading2'); $c->configure(-sortable=>0);

4. my $hml=$mw->HMListbox; $hml->columnInsert(0,-text=>'Heading1'); $hml->columnInsert(0,-text=>'Heading2'); $hml->columnConfigure(0,-sortable=>0);

(See the columnConfigure() method below for details on column options).

All column methods expects one or two column indices as arguments. The column indices might be an integer (between 0 and the number of columns minus one), 'end' for the last column, or a reference to the HMLColumn widget (obtained by calling HMListbox->columnGet() or by storing the return value from HMListbox->columnInsert()).

WIDGET METHODS

$hml->compound([left|right|top|bottom])

Gets / sets the side of the column header that the ascending / descending arrow is to appear (left, right, top, bottom). Default: "right".

$hml->focusColumn([index])

DEPRECIATED: Gets or sets the index of the column whose listbox is to receive the keyboard focus when the HMListbox widget receives keyboard focus. This is a holdover from Tk::SMListbox, where it is useful to better display the active element cursor due to the fact that it depends on Tk::Listbox, which does not display the active element (usually underlined) unless the listbox itself has the focus. This allows the programmer to specify a colum other than the first one, ie, if the main column of interest to the user is not the first one.

Tk::HMListbox depends instead on Tk::HListbox, which does display the active element without specifically being focused making it unnecessary to designate a specific widget to show the active cursor, so therefore all column listboxes show the active element regardless of which has the focus and Tk::HListbox can assign the first column (the default if this isn't specified here) the focus and everything displays properly.

NOTE: none of this applies if -nocolumnfocus is set, which also has the side effect of disabling most keyboard bindings on the HMListbox.

$hml->getSortOrder()

Returns an array that is in the same format accepted by the $smListBox->sort method. The 1st element is either true for descending sort, false for assending. Subsequent elements represent the column indices of one or more columns by which the data is sorted. Default (if nothing previously set): (0, 0).

$hml->setSortOrder(descending, columnindex...)

Sets the default sort order and columns to sort without actually sorting. The arguments are the same as the sort() function.

$hml->setButtonHeight([pady])

Sets (alters) the "-pady" value for the header buttons. Should be called AFTER all columns have been created. Requires version 2 or higher.

$hml->showallsortcolumns([1|0])

Gets or sets whether a sort direction arrow is to be displayed on each column involved in the sorting or just the 1st (primary sort). Default: 0 (false) - show arrow only on the primary sort column.

$hml->bindColumns(sequence,callback)

Adds the binding to all column headers in the widget. See the section BINDING EVENTS TO HMListbox below.

$hml->bindRows(sequence,callback)

Adds the binding to all listboxes in the widget. See the section BINDING EVENTS TO HMListbox below.

$hml->bindSeparators(sequence,callback)

Adds the binding to all separators in the widget. See the section BINDING EVENTS TO HMListbox below.

COLUMN METHODS

(Methods for accessing and manipulating individual columns in the HMListbox widget)

$hml->columnConfigure(index,option=>value...)

Set option values for a specific column. Equal to $hml->columnGet(index)->configure(...).

The following column options are supported:

-comparecommand => callback

Specifies a callback to use when sorting the HMListbox with this column as key. The callback will be called with two scalar arguments, each a value from this particular column. The callback should return an integer less than, equal to, or greater than 0, depending on how the tow arguments are ordered. If for example the column should be sorted by numerical value:

    -comparecommand => sub { $_[0] <=> $_[1]}

Default: sub { $_[0] cmp $_[1] } #(Ascending by string) NOTE: If the column data is images or hashrefs (both text and images or contains additional cell-specific options, then one should specify a component of that hash to sort by, ie. the special "-sort" key is handy, then one can sort using something like:

        sub { $_[0]->{'-sort'} cmp $_[1]->{'-sort'} } or maybe:

        sub { $_[0]->{'-text'} cmp $_[1]->{'-text'} }
-text => string

Specifies the text to be used in the heading button of the column.

-resizeable => boolean

A value of 1 indicates that it is okay for the user to resize this column by dragging the separator. 0 disables this function. Default: 1.

-separatorcolor => string

Specifies the color of the separator line. Default: black.

-separatorwidth => integer

Specifies the width of the separator line in pixels. Default: 1.

-sortable => boolean

A value of 1 indicates that it is okay for the user to sort the data by clicking this column's heading. 0 disables this function. Default: 1.

-itemtype => "text" | "imagetext"

New option (not included with Tk::SMListbox or Tk::MListbox) that permits a column to contain either images and or text in it's entries. Valid values are "text" and "imagetext". Default: "text".

-reversearrow => 0 | 1

New option (not included with the old Tk::MListbox) that causes the up / down direction of the sort arrow in the column header that shows the direction the sorted-by column is currently sorted. Default: 0 (zero) - (Up-arrow if sorted in ascending order, Down-arrow if in descending order. Setting to 1 reverses this. This is often necessary to show desired results, ie. if the sort function is reversed, such as: sub { $_[1] cmp $_[0] }

$hml->columnDelete(first,last)

If last is omitted, deletes column first. If last is specified, deletes all columns from first to last, inclusive.

All previous column indices greater than last (or first if last is omitted) are decremented by the number of columns deleted.

$hml->columnGet(first,last)

If last is not specified, returns the HMLColumn widget specified by first. If both first and last are specified, returns an array containing all columns from first to last.

$hml->columnHide(first,last)

If last is omitted, hides column first. If last is specified, hides all columns from first to last, inclusive.

Hiding a column is equal to calling $hml->columnGet(index)->packForget. The column is not deleted, all data are still available, and the column indices remain the same.

See also the columnShow() method below.

$hml->columnIndex(index)

Returns an integer index for the column specifed by index.

$hml->columnInsert(index,option=>value...)

Creates a new column in the HMListbox widget. The column will get the index specified by index. If index is 'end', the new column's index will be one more than the previous highest column index.

If column index exists, the new column will be placed to the left of this column. All previous column indices equal to or greater than index will be incremented by one.

Returns the newly created HMLColumn widget.

(See the columnConfigure() method above for details on column options).

$hml->columnPack(array)

Repacks all columns in the HMListbox widget according to the specification in array. Each element in array is a string on the format index:width. index is a column index, width defines the columns width in pixels (may be omitted). The columns are packed left to right in the order specified by by array. Columns not specified in array will be hidden.

This method is most useful if used together with the columnPackInfo() method.

$hml->columnPackInfo()

Returns an array describing the current layout of the HMListbox widget. Each element of the array is a string on the format index:width (see columnPack() above). Only indices of columns that are currently shown (not hidden) will be returned. The first element in the returned array represents the leftmost column.

This method may be used in conjunction with columnPack() to save and restore the column configuration.

$hml->columnShow(index,option=>value)

Shows a hidden column (see the columnHide() method above). The column to show is specified by index.

By default, the column is pack'ed at the rigthmost end of the HMListbox widget. This might be overridden by specifying one of the following options:

-after => index

Place the column after (to the right of) the column specified by index.

-before => index

Place the column before (to the left of) the column specified by index.

ROW METHODS

(Methods for accessing and manipulating rows of data)

Many of the methods for HMListbox take one or more indices as arguments. See Tk::HListbox for a description of row indices.

$hml->delete(first,last)

Deletes one or more row elements of the HMListbox. First and last are indices specifying the first and last elements in the range to delete. If last isn't specified it defaults to first, i.e. a single element is deleted.

$hml->get(first,last)

If last is omitted, returns the content of the HMListbox row indicated by first. If last is specified, the command returns a list whose elements are all of the listbox rows between first and last.

The returned elements are all array references. The referenced arrays contains one element for each column of the HMListbox.

$hml->getRow(index)

In scalar context, returns the value of column 0 in the HMListbox row specified by index. In list context, returns the content of all columns in the row as an array.

This method is provided for convenience, since retrieving a single row with the get() method might produce some ugly code.

The following two code snippets are equal:

   1. @row=$hml->getRow(0);

   2. @row=@{($hml->get(0))[0]};
$hml->sort(descending, columnindex...)

Sorts the content of the HMListbox. If descending is a true value, the sort order will be descending. Default is 0 - ascending sort on first column (0).

If columnindex is specified, the sort will be done with the specified column as key. You can specify as many columnindex arguments as you wish. Sorting is done on the first column, then on the second, etc...

The default is to sort the data on all columns of the listbox, with column 0 as the first sort key, column 1 as the second, etc.

OTHER LISTBOX METHODS

Most other Tk::HListbox methods works for the HMListbox widget. This includes the methods activate, cget, curselection, index, nearest, see, selectionXXX, size, xview, yview.

See Tk::HListbox

BINDING EVENTS TO HMLISTBOX

Calling $hml->bind(...) probably makes little sense, since the call does not specify whether the binding should apply to the listbox, the header button or the separator line between each column.

In stead of the ordinary bind, the following methods should be used:

$hml->bind(sequence,callback)

Synonym for $hml->bindRows(sequence,callback).

$hml->bindRows(sequence,callback)

Synonym for $hml->bindSubwidgets('listbox',sequence,callback)

$hml->bindColumns(sequence,callback)

Synonym for $hml->bindSubwidgets('heading',sequence,callback)

$hml->bindSeparators(sequence,callback)

Synonym for $hml->bindSubwidgets('separator',sequence,callback)

$hml->bindSubwidgets(subwidget,sequence,callback)

Adds the binding specified by sequence and callback to all subwidgets of the given type (should be 'listbox', 'heading' or 'separator').

The binding is stored in the widget, and if you create a new column by calling $hml->columnInsert(), all bindings created by $hml->bindSubwidgets() are automatically copied to the new column.

The callback is called with the HMListbox widget as first argument, and the index of the column where the event occured as the second argument.

NOTE that $hml->bindSubwidgets() does not support all of Tk's callback formats. The following are supported:

     \&subname
     sub { code }
     [ \&subname, arguments...]
     [ sub { code }, arguments...]

If sequence is undefined, then the return value is a list whose elements are all the sequences for which there exist bindings for subwidget.

If sequence is specified without callback, then the callback currently bound to sequence is returned, or an empty string is returned if there is no binding for sequence.

If sequence is specified, and callback is an empty string, then the current binding for sequence is destroyed, leaving sequence unbound. An empty string is returned.

An empty string is returned in all other cases.

KEYWORDS

hmlistbox, smlistbox, mlistbox, listbox, hlist, widget

SEE ALSO

Tk::SMListbox Tk::MListbox Tk::HListbox