NAME
Tk::MListbox - Multicolumn Listbox.
SYNOPSIS
$ml = $parent->MListbox (<options>);
DESCRIPTION
Tk::MListbox is a multicolumn Listbox widget with builtin capabilites for sorting, resizing and repositioning of the columns.
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.
The columns may be resized by dragging a separator line which is drawn between each column.
A column's position in the widget might be changed by dragging it's heading left or right.
Tk::MListbox is used in a way similar to the standard Listbox, but in stead of scalar values MListbox operates on lists of data. In addition to methods for accessing the data in the MListbox, the widget offer methods for manipulation of the individual columns.
STANDARD OPTIONS
-background -foreground -relief -takefocus -borderwidth -height -selectbackground -cursor -highlightbackground -selectborderwidth -xscrollcommand -exportselection -highlightcolor -selectforeground -yscrollcommand -font -highlightthickness -setgrid
See Tk::options for details of the standard options.
REQUIREMENTS
Tk::MListbox requires Tk::Pane. (and basic Perl/Tk of course....)
WIDGET SPECIFIC OPTIONS
- -columns => list
-
Defines the columns in the widget. Each element in the list describes a column. See the COLUMNS section below.
- -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
- -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 is "browse". See Tk::Listbox.
- -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.
COLUMNS
The MListbox widget is a collection of MLColumn widgets. Each MLColumn contains a Listbox, 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 MListbox::configure(-columns), MListbox::insert(), MListbox::columnConfigure() or MLColumn::configure().
The following code snippets are all equal:
1. $ml=$mw->MListbox(-columns=>[[-text=>'Heading1', -sortable=>0], [-text=>'Heading2']]);
2. $ml=$mw->MListbox; $ml->columnInsert(0,-text=>'Heading1', -sortable=>0); $ml->columnInsert(0,-text=>'Heading2');
3. $ml=$mw->MListbox; $c=$ml->columnInsert(0,-text=>'Heading1'); $ml->columnInsert(0,-text=>'Heading2'); $c->configure(-sortable=>0);
4. $ml=$mw->MListbox; $ml->columnInsert(0,-text=>'Heading1'); $ml->columnInsert(0,-text=>'Heading2'); $ml->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 MLColumn widget (obtained by calling MListbox->columnGet() or by storing the return value from MListbox->columnInsert()).
COLUMN METHODS
(Methods for accessing and manipulating individual columns in the MListbox widget)
- $ml->columnConfigure(index,option=>value...)
-
Set option values for a specific column. Equal to $ml->columnGet(index)->configure(...).
The following column options are supported:
-comparecmd => callback
Specifies a callback to use when sorting the MListbox 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:
-comparecmd => sub { $_[0] <=> $_[1]}
The default is to sort the columns alphabetically.
-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 is black.
-separatorwidth => integer
Specifies the width of the separator line in pixels. Default is 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
- $ml->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.
- $ml->columnGet(index)
-
Returns the MLColumn widget specified by index.
- $ml->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 $ml->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.
- $ml->columnIndex(index)
-
Returns an integer index for the column specifed by index.
- $ml->columnInsert(index,option=>value...)
-
Creates a new column in the MListbox 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 MLColumn widget.
(See the columnConfigure() method above for details on column options).
- $ml->columnPack(array)
-
Repacks all columns in the MListbox 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.
- $ml->columnPackInfo
-
Returns an array describing the current layout of the MListbox 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.
- $ml->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 MListbox 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 MListbox take one or more indices as arguments. See Tk::Listbox for a description of row indices.
- $ml->delete(first,last)
-
Deletes one or more row elements of the MListbox. 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.
- $ml->get(first,last)
-
If last is omitted, returns the content of the MListbox 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 MListbox.
- $ml->getRow(index)
-
In scalar context, returns the value of column 0 in the MListbox row specified by index. In list context, returns the content of all columns in the row as an array.
This method is provided for convenience, since retrieving a single row with the get() method might produce some ugly code.
The following two code snippets are equal:
1. @row=$ml->getRow(0); 2. @row=@{($ml->get(0))[0]};
- $ml->sort(descending, columnindex...)
-
Sorts the content of the MListbox. If descending is a true value, the sort order will be descending. The default is ascending sort.
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::Listbox methods works for the MListbox widget. This includes the methods activate, cget, curselection, index, nearest, see, selectionXXX, size, xview, yview.
See Tk::Listbox.
ADVERTISED SUBWIDGETS
- pane
-
All MListbox columns are packed inside a Tk::Pane (this is done to enable horizontal scrolling).
Apart from "pane", the MListbox widget has no subwidgets, except for the variable number of MLColumns, which obviously cannot be advertised. The MLColumn widgets might be obtained by calling the columnGet() or columnInsert() methods.
The MLColumn widget (which represents a single column in the MListbox) advertises the following subwidgets:
- listbox
-
The individual Listbox. Note that this is not the standard Tk::Listbox, but a derived version (CListbox). Several of the widget's methods will not work as expected.
- separator
-
The column separator line. This is a Canvas.
- heading
-
The column heading. This is a Button.
- frame
-
A Frame which contains the "listbox" and the "heading" subwidgets (but not the "separator").
Example: If you want to change the background color of the heading of column 4:
$ml->columnGet(4)->Subwidget("heading")
->configure(-background=>'blue');
6 POD Errors
The following errors were encountered while parsing the POD:
- Around line 863:
You forgot a '=back' before '=head1'
- Around line 911:
'=item' outside of any '=over'
- Around line 1067:
You forgot a '=back' before '=head1'
- Around line 1074:
'=item' outside of any '=over'
- Around line 1121:
You forgot a '=back' before '=head1'
- Around line 1131:
'=item' outside of any '=over'