Commands for Interactive Sorting by One or More Columns

For Tablelist Version 7.4

by

Csaba Nemethi

csaba.nemethi@t-online.de

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Overview

The commands described in this reference page enable the user to sort the items of a tablelist widget based on one or more of its columns, with the aid of the left mouse button.

If the tablelist::sortByColumn command was specified as the value of the -labelcommand configuration option, then by pressing mouse button 1 over one of the header labels and later releasing it over the same label, the items will be sorted based on the elements of the corresponding column.

If the tablelist::addToSortColumns command was specified as the value of the -labelcommand2 configuration option, then by pressing mouse button 1 together with the Shift key over one of the header labels and later releasing it over the same label, the corresponding column will be appended to the list of sort columns, or (if it was already contained in that list) the corresponding sort order will be toggled; in both cases, the items will be sorted based on the updated lists of sort columns and sort orders.

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The tablelist::sortByColumn Command

NAME
tablelist::sortByColumn – Sort the items of a tablelist widget based on one of its columns
SYNOPSIS
tablelist::sortByColumn pathName columnIndex
DESCRIPTION
This command sorts the items of the tablelist widget pathName based on the elements of the column specified by columnIndex.  This is done by invoking the sortbycolumn subcommand of the Tcl command associated with the given tablelist widget.  If the items were last sorted in increasing order, based on the same column given by columnIndex, and no subsequent invocation of the resetsortinfo subcommand was made, then the last argument passed to sortbycolumn will be -decreasing, otherwise -increasing.
After sorting the items, the virtual event <<TablelistColumnSorted>> is generated.  For Tk versions 8.5 or higher, this virtual event is generated with its -data option set to a list consisting of the numerical column index and the sort order (decreasing or increasing).  The command returns the sort order, as decreasing or increasing.
If the specified column's -showlinenumbers option has been set to true, then the actions described above are not performed and the return value is an empty string.
tablelist::sortByColumn is usually specified as the value of the -labelcommand configuration option for a tablelist widget.
KEYWORDS
tablelist, sort, column, widget

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The tablelist::addToSortColumns Command

NAME
tablelist::addToSortColumns – Add a column index to the list of sort columns and perform the multi-column sorting
SYNOPSIS
tablelist::addToSortColumns pathName columnIndex
DESCRIPTION
This command adds the column index specified by columnIndex to the list of sort columns of the tablelist widget pathName and sorts the items based on the elements of the columns indicated by the modified list.  This is done by invoking the sortbycolumnlist subcommand of the Tcl command associated with the given tablelist widget.  The two arguments passed to sortbycolumnlist are built as follows: (a) if the given column index is already contained in the widget's list of sort columns (returned by the sortcolumnlist subcommand) then this list is left unchanged and the sort order list (returned by the sortorderlist subcommand) is updated by toggling its corresponding element from increasing to decreasing and vice-versa; (b) otherwise the column index is appended to the list of sort columns and the value increasing is appended to the list of sort orders.
After sorting the items by passing the two updated lists to the sortbycolumnlist subcommand, the virtual event <<TablelistColumnsSorted>> (note the plural form!) is generated.  For Tk versions 8.5 or higher, this virtual event is generated with its -data option set to a list consisting of the two above-mentioned updated lists passed to sortbycolumnlist as arguments.  The command returns the new sort order corresponding to the given column, as decreasing or increasing.
If the specified column's -showlinenumbers option has been set to true, then the actions described above are not performed and the return value is an empty string.
tablelist::addToSortColumns is usually specified as the value of the -labelcommand2 configuration option for a tablelist widget.
KEYWORDS
tablelist, sort, column list, widget

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