ntextBindings(n) Alternative Bindings for the Text Widget ntextBindings(n)______________________________________________________________________________NAMEntextBindings - Alternative Bindings for the Text Widget
SYNOPSIS
package require Tcl 8.5
package require Tk 8.5
package require ntext ?0.81?
_________________________________________________________________DESCRIPTION
The ntext package provides a binding tag named Ntext for use by text
widgets in place of the default Text binding tag.
The Text binding tag provides around one hundred bindings to the text
widget (the exact number is platform-dependent). A few of these behave
in a way that is different from most contemporary text-editing applica‐
tions. Ntext aims to provide more familiar behaviour.
Features of the Ntext bindings that differ from the default Text bind‐
ings:
· Clicking near the end of a (logical) line moves the cursor to
the end of that line (not the start of the next line). If the
widget is in -wrap word mode, the same rule applies to display
lines.
· Double-clicking or dragging near the end of a (logical) line
will highlight/select characters from the end of that line (not
the next line, or the region at the end of the line where there
are no characters). If the widget is in -wrap word mode, the
same rule applies to display lines.
· The End key implements "Smart End" (successive keypresses move
the cursor to the end of the display line, then to the end of
the logical line); the Home key implements "Smart Home" (which
is similar to "Smart End", but also toggles between the begin‐
ning and end of leading whitespace).
· When a selection exists, a <<Paste>> operation (e.g. <Control-
v>) overwrites the selection (as most editors do), and does so
on all platforms.
· The <Insert> key toggles between "Insert" and "Overwrite" modes
for keyboard input. (In contrast, the Text binding tag uses
<Insert> as a method to paste the "primary selection", a task
that can be accomplished instead by mouse middle-click.)
· The <Escape> key clears the selection.
· Selecting with <Shift-Button1> selects from the previous posi‐
tion of the insertion cursor. (In the Text binding tag, the
selection anchor may be the position of the previous mouse
click.)
· <Shift-Button1> operations do not alter the selection anchor.
(In the Text binding tag, they do.)
· By default, the Ntext binding tag does not provide several of
the Control-key bindings supplied by the Text binding tag. Mod‐
ern keyboards offer alternatives, such as cursor keys for navi‐
gation; modern applications often use the Control-key bindings
for other purposes (e.g. <Control-p> for "print").
The last three cases, the behavior of Text is often useful, so Ntext
gives you the option of retaining it, by setting variables defined in
the ::ntext namespace to 1 (instead of their default 0). Explaining
these features in more detail:
· If the mouse is clicked at position A, then the keyboard is used
to move the cursor to B, then shift is held down, and the mouse
is clicked at C: the Text binding tag gives a selection from A
to C; the Ntext gives a selection from B to C. If you want
Ntext to behave like Text in this respect, set ::ntext::classic‐
MouseSelect to 1.
· The Text binding tag allows successive <Shift-Button-1> events
to change both ends of the selection, by moving the selection
anchor to the end of the selection furthest from the mouse
click. Instead, the Ntext binding tag fixes the anchor, and
multiple Shift-Button-1 events can only move the non-anchored
end of the selection. If you want Ntext to behave like Text in
this respect, set ::ntext::classicAnchor to 1. In both Text and
Ntext, keyboard navigation with the Shift key held down alters
the selection and keeps the selection anchor fixed.
· The following "extra" Text bindings are switched off by default,
but can be activated in Ntext by setting ::ntext::classicExtras
to 1: <Control-a>, <Control-b>, <Control-d>, <Control-e>, <Con‐
trol-f>, <Control-h>, <Control-i>, <Control-k>, <Control-n>,
<Control-o>, <Control-p>, <Control-t>, <Control-space>, <Con‐
trol-Shift-space>.
CONFIGURATION OPTIONS
Ntext provides alternatives to a number of behaviours of the classic
Text binding tag. Where there is an option, the Ntext behaviour is
switched on by default, except for display-line indentation which is
discussed on a separate page at ntextIndent.
The behaviour of Ntext may be configured application-wide by setting
the values of a number of namespace variables:
::ntext::classicAnchor
· 0 - (default value) selects Ntext behaviour, i.e. the anchor
point is fixed
· 1 - selects classic Text behaviour, i.e. the anchor point is
variable
::ntext::classicExtras
· 0 - (default value) selects Ntext behaviour, i.e. several
"extra" Text bindings are de-activated
· 1 - selects classic Text behaviour, i.e. the "extra" Text bind‐
ings are activated
::ntext::classicMouseSelect
· 0 - (default value) selects Ntext behaviour, i.e. the anchor
point for mouse selection operations is moved by keyboard navi‐
gation
· 1 - selects classic Text behaviour
::ntext::overwrite
· 0 - (initial value) text typed at the keyboard is inserted into
the widget
· 1 - text typed at the keyboard overwrites text already in the
widget
· The value is toggled by the Insert key.
EXAMPLE
To use Ntext but keep classic Text 's variable-anchor feature:
package require ntext
text .t
set ::ntext::classicAnchor 1
bindtags .t {.t Ntext . all}
SEE ALSO
bindtags, ntext, ntextIndent, text
KEYWORDS
bindtags, text
ntext 0.81 ntextBindings(n)
