Author: Peter Spjuth <[email protected]>
State: Draft
Type: Project
Vote: Pending
Created: 19-Sep-2019
Post-History:
Tcl-Version: 8.7
Keywords: Tk, treeview
Tk-Branch: pspjuth-treeview
Abstract
This TIP proposes a set of new features for the Ttk treeview widget.
Rationale
Each time I have tried to use the Treeview widget it fell short of some feature or another and I had to resort to other means.
This aims to fill in the most common missing pieces.
Specification
The following features are added to the treeview widget.
Locked horizontal scrolling
Adds the ability to lock the first display column(s) from horizontal scrolling.
A new option -titlecolumns n is added, requesting columns to be locked. The tree column counts, even if -show tree is not specified. This is to follow the semantics of #N-indexing of columns. Thus for value N of this option, column #N is the first one that is scrollable.
Cell selection
Adds the ability to select individual cells as well as full rows.
Cell selection is independent of item selection.
Cells are identified with a two element list with item id and column id.
A new subcommand cellselection is added, mirroring the present selection. In addition the cellselection set and cellselection add commands get a version for selecting a rectangular range.
A new option -selecttype type is added to direct default bindings to use either item selection or cell selection.
The identify subcommand is updated with the cell option.
Default bindings are updated to use these features.
The <
Striped rows
A new option -striped bool is added. This makes every other row get marked
with the alternate
state, and allows the theme to draw them in a
different color. Built in themes are updated to put something fitting
at that color.
Column separators
The -show option is extended with the value columnseparators
to
display a separator between columns.
Built in themes are updated to define the separators.
Image anchor for tree
A new item option -imageanchor anchor is added. This controls the placement of the image relative to the text in an item's tree column. Default is "w".
Implementation
Started on branch pspjuth-treeview
Copyright
This document has been placed in the public domain.