Entry(3pm) User Contributed Perl Documentation Entry(3pm)NAMETk::Entry - Create and manipulate Entry widgets
SYNOPSIS
$entry = $parent->Entry(?options?);
STANDARD OPTIONS-background-highlightbackground-insertontime-selectforeground
-borderwidth-highlightcolor-insertwidth-takefocus
-cursor-highlightthickness -justify -textvariable
-exportselection-insertbackground-relief-xscrollcommand
-font-insertborderwidth-selectbackground
-foreground-insertofftime -selectborderwidth
WIDGET-SPECIFIC OPTIONS
Command-Line Name: -disabledbackground
Database Name: disabledBackground
Database Class: DisabledBackground
Specifies the background color to use when the entry is disabled.
If this option is the empty string, the normal background color is
used.
Command-Line Name: -disabledforeground
Database Name: disabledForeground
Database Class: DisabledForeground
Specifies the foreground color to use when the entry is disabled.
If this option is the empty string, the normal foreground color is
used.
Name: invalidCommand
Class: InvalidCommand
Switch: -invalidcommand
Alias: -invcmd
Specifies a script to eval when validateCommand returns 0. Setting
it to <undef> disables this feature (the default). The best use of
this option is to set it to bell. See Validation below for more
information.
Command-Line Name: -readonlybackground
Database Name: readonlyBackground
Database Class: ReadonlyBackground
Specifies the background color to use when the entry is read-only.
If this option is the empty string, the normal background color is
used.
Name: show
Class: Show
Switch: -show
If this option is specified, then the true contents of the entry
are not displayed in the window. Instead, each character in the
entry's value will be displayed as the first character in the value
of this option, such as ``*''. This is useful, for example, if the
entry is to be used to enter a password. If characters in the
entry are selected and copied elsewhere, the information copied
will be what is displayed, not the true contents of the entry.
Name: state
Class: State
Switch: -state
Specifies one of three states for the entry: normal, disabled, or
readonly. If the entry is readonly, then the value may not be
changed using widget commands and no insertion cursor will be
displayed, even if the input focus is in the widget; the contents
of the widget may still be selected. If the entry is disabled, the
value may not be changed, no insertion cursor will be displayed,
the contents will not be selectable, and the entry may be displayed
in a different color, depending on the values of the
-disabledforeground and -disabledbackground options.
Name: validate
Class: Validate
Switch: -validate
Specifies the mode in which validation should operate: none, focus,
focusin, focusout, key, or all. It defaults to none. When you
want validation, you must explicitly state which mode you wish to
use. See Validation below for more.
Name: validateCommand
Class: ValidateCommand
Switch: -validatecommand
Alias: -vcmd
Specifies a script to eval when you want to validate the input into
the entry widget. Setting it to "undef" disables this feature (the
default). This command must return a valid boolean value. If it
returns 0 (or the valid boolean equivalent) then it means you
reject the new edition and it will not occur and the invalidCommand
will be evaluated if it is set. If it returns 1, then the new
edition occurs. See Validation below for more information.
Name: width
Class: Width
Switch: -width
Specifies an integer value indicating the desired width of the
entry window, in average-size characters of the widget's font. If
the value is less than or equal to zero, the widget picks a size
just large enough to hold its current text.
DESCRIPTION
The Entry method creates a new window (given by the $entry argument)
and makes it into an entry widget. Additional options, described
above, may be specified on the command line or in the option database
to configure aspects of the entry such as its colors, font, and relief.
The entry command returns its $entry argument. At the time this
command is invoked, there must not exist a window named $entry, but
$entry's parent must exist.
An entry is a widget that displays a one-line text string and allows
that string to be edited using methods described below, which are
typically bound to keystrokes and mouse actions. When first created,
an entry's string is empty. A portion of the entry may be selected as
described below. If an entry is exporting its selection (see the
exportSelection option), then it will observe the standard X11
protocols for handling the selection; entry selections are available
as type STRING. Entries also observe the standard Tk rules for dealing
with the input focus. When an entry has the input focus it displays an
insertion cursor to indicate where new characters will be inserted.
Entries are capable of displaying strings that are too long to fit
entirely within the widget's window. In this case, only a portion of
the string will be displayed; methods described below may be used to
change the view in the window. Entries use the standard xScrollCommand
mechanism for interacting with scrollbars (see the description of the
-xscrollcommand option for details). They also support scanning, as
described below.
VALIDATION
Validation of entry widgets is derived from part of the patch written
by jhobbs@cs.uoregon.edu. This works by setting the validateCommand
option to a callback which will be evaluated according to the validate
option as follows:
none
Default. This means no validation will occur.
focus
validateCommand will be called when the entry receives or loses
focus.
focusin
validateCommand will be called when the entry receives focus.
focusout
validateCommand will be called when the entry loses focus.
key validateCommand will be called when the entry is edited.
all validateCommand will be called for all above conditions.
The validateCommand and invalidCommand are called with the following
arguments:
· The proposed value of the entry. If you are configuring the entry
widget to have a new textvariable, this will be the value of that
textvariable.
· The characters to be added (or deleted). This will be "undef" if
validation is due to focus, explcit call to validate or if change
is due to "-textvariable" changing.
· The current value of entry i.e. before the proposed change.
· index of char string to be added/deleted, if any. -1 otherwise
· type of action. 1 == INSERT, 0 == DELETE, -1 if it's a forced
validation or textvariable validation
In general, the textVariable and validateCommand can be dangerous to
mix. If you try set the textVariable to something that the
validateCommand will not accept it will be set back to the value of the
entry widget. Using the textVariable for read-only purposes will never
cause problems.
The validateCommand will turn itself off by setting validate to none
when an error occurs, for example when the validateCommand or
invalidCommand encounters an error in its script while evaluating, or
validateCommand does not return a valid boolean value.
With the perl/Tk version validate option is supposed to be "suspended"
while executing the validateCommand or the invalidCommand. This is
experimental but in theory either callback can "correct" the value of
the widget, and override the proposed change. (validateCommand should
still return false to inhibit the change from happening when it
returns.)
WIDGET METHODS
The Entry method creates a widget object. This object supports the
configure and cget methods described in Tk::options which can be used
to enquire and modify the options described above. The widget also
inherits all the methods provided by the generic Tk::Widget class.
Many of the additional methods for entries take one or more indices as
arguments. An index specifies a particular character in the entry's
string, in any of the following ways:
number
Specifies the character as a numerical index, where 0 corresponds
to the first character in the string.
anchor
Indicates the anchor point for the selection, which is set with the
selectionFrom and selectionAdjust methods.
end Indicates the character just after the last one in the entry's
string. This is equivalent to specifying a numerical index equal
to the length of the entry's string.
insert
Indicates the character adjacent to and immediately following the
insertion cursor.
sel.first
Indicates the first character in the selection. It is an error to
use this form if the selection isn't in the entry window.
sel.last
Indicates the character just after the last one in the selection.
It is an error to use this form if the selection isn't in the entry
window.
@number
In this form, number is treated as an x-coordinate in the entry's
window; the character spanning that x-coordinate is used. For
example, ``@0'' indicates the left-most character in the window.
Abbreviations may be used for any of the forms above, e.g. ``e'' or
``sel.f''. In general, out-of-range indices are automatically rounded
to the nearest legal value.
The following additional methods are available for entry widgets:
$entry->bbox(index)
Returns a list of four numbers describing the bounding box of the
character given by index. The first two elements of the list give
the x and y coordinates of the upper-left corner of the screen area
covered by the character (in pixels relative to the widget) and the
last two elements give the width and height of the character, in
pixels. The bounding box may refer to a region outside the visible
area of the window.
$entry->cget(?option?)
Returns the current value of the configuration option given by
option. Option may have any of the values accepted by the entry
command.
$entry->configure(?option?, ?value, option, value, ...?)
Query or modify the configuration options of the widget. If no
option is specified, returns a list describing all of the available
options for $entry (see Tk::configure for information on the format
of this list). If option is specified with no value, then the
command returns a list describing the one named option (this list
will be identical to the corresponding sublist of the value
returned if no option is specified). If one or more option-value
pairs are specified, then the command modifies the given widget
option(s) to have the given value(s); in this case the command
returns an empty string. Option may have any of the values
accepted by the entry command.
$entry->delete(first, ?last?)
Delete one or more elements of the entry. First is the index of
the first character to delete, and last is the index of the
character just after the last one to delete. If last isn't
specified it defaults to first+1, i.e. a single character is
deleted. This method returns an empty string.
$entry->get
Returns the entry's string.
$entry->icursor(index)
Arrange for the insertion cursor to be displayed just before the
character given by index. Returns an empty string.
$entry->index(index)
Returns the numerical index corresponding to index.
$entry->insert(index, string)
Insert the characters of string just before the character indicated
by index. Returns an empty string.
$entry->scan(option, args)
$entry->scanOption(args)
This method is used to implement scanning on entries. It has two
forms, depending on Option:
$entry->scanMark(x)
Records x and the current view in the entry widget; used
in conjunction with later scanDragto methods. Typically
this method is associated with a mouse button press in the
widget. It returns an empty string.
$entry->scanDragto(x)
This method computes the difference between its x argument
and the x argument to the last scanMark method for the
widget. It then adjusts the view left or right by 10 times
the difference in x-coordinates. This method is typically
associated with mouse motion events in the widget, to
produce the effect of dragging the entry at high speed
through the widget. The return value is an empty string.
$entry->selection(option, arg)
$entry->selectionOption(arg)
This method is used to adjust the selection within an entry. It
has several forms, depending on Option:
$entry->selectionAdjust(index)
Locate the end of the selection nearest to the character
given by index, and adjust that end of the selection to be
at index (i.e including but not going beyond index). The
other end of the selection is made the anchor point for
future selectionTo methods. If the selection isn't
currently in the entry, then a new selection is created to
include the characters between index and the most recent
selection anchor point, inclusive. Returns an empty
string.
$entry->selectionClear
Clear the selection if it is currently in this widget. If
the selection isn't in this widget then the method has no
effect. Returns an empty string.
$entry->selectionFrom(index)
Set the selection anchor point to just before the character
given by index. Doesn't change the selection. Returns an
empty string.
$entry->selectionPresent
Returns 1 if there is are characters selected in the entry,
0 if nothing is selected.
$entry->selectionRange(start, end)
Sets the selection to include the characters starting with
the one indexed by start and ending with the one just
before end. If end refers to the same character as start
or an earlier one, then the entry's selection is cleared.
$entry->selectionTo(index)
If index is before the anchor point, set the selection to
the characters from index up to but not including the
anchor point. If index is the same as the anchor point, do
nothing. If index is after the anchor point, set the
selection to the characters from the anchor point up to but
not including index. The anchor point is determined by the
most recent selectionFrom or selectionAdjust method in this
widget. If the selection isn't in this widget then a new
selection is created using the most recent anchor point
specified for the widget. Returns an empty string.
$entry->validate
This command is used to force an evaluation of the validateCommand
independent of the conditions specified by the validate option. It
returns 0 or 1.
$entry->xview(args)
This command is used to query and change the horizontal position of
the text in the widget's window. It can take any of the following
forms:
$entry->xview
Returns a list containing two elements. Each element is a
real fraction between 0 and 1; together they describe the
horizontal span that is visible in the window. For
example, if the first element is .2 and the second element
is .7, 20% of the entry's text is off-screen to the left,
the middle 50% is visible in the window, and 30% of the
text is off-screen to the right. These are the same values
passed to scrollbars via the -xscrollcommand option.
$entry->xview(index)
Adjusts the view in the window so that the character given
by index is displayed at the left edge of the window.
$entry->xviewMoveto(fraction)
Adjusts the view in the window so that the character
fraction of the way through the text appears at the left
edge of the window. Fraction must be a fraction between 0
and 1.
$entry->xviewScroll(number, what)
This method shifts the view in the window left or right
according to number and what. Number must be an integer.
What must be either units or pages or an abbreviation of
one of these. If what is units, the view adjusts left or
right by number average-width characters on the display;
if it is pages then the view adjusts by number screenfuls.
If number is negative then characters farther to the left
become visible; if it is positive then characters farther
to the right become visible.
DEFAULT BINDINGS
Tk automatically creates class bindings for entries that give them the
following default behavior. In the descriptions below, ``word'' refers
to a contiguous group of letters, digits, or ``_'' characters, or any
single character other than these.
[1] Clicking mouse button 1 positions the insertion cursor just before
the character underneath the mouse cursor, sets the input focus to
this widget, and clears any selection in the widget. Dragging with
mouse button 1 strokes out a selection between the insertion cursor
and the character under the mouse.
[2] Double-clicking with mouse button 1 selects the word under the
mouse and positions the insertion cursor at the beginning of the
word. Dragging after a double click will stroke out a selection
consisting of whole words.
[3] Triple-clicking with mouse button 1 selects all of the text in the
entry and positions the insertion cursor before the first
character.
[4] The ends of the selection can be adjusted by dragging with mouse
button 1 while the Shift key is down; this will adjust the end of
the selection that was nearest to the mouse cursor when button 1
was pressed. If the button is double-clicked before dragging then
the selection will be adjusted in units of whole words.
[5] Clicking mouse button 1 with the Control key down will position the
insertion cursor in the entry without affecting the selection.
[6] If any normal printing characters are typed in an entry, they are
inserted at the point of the insertion cursor.
[7] The view in the entry can be adjusted by dragging with mouse button
2. If mouse button 2 is clicked without moving the mouse, the
selection is copied into the entry at the position of the mouse
cursor.
[8] If the mouse is dragged out of the entry on the left or right sides
while button 1 is pressed, the entry will automatically scroll to
make more text visible (if there is more text off-screen on the
side where the mouse left the window).
[9] The Left and Right keys move the insertion cursor one character to
the left or right; they also clear any selection in the entry and
set the selection anchor. If Left or Right is typed with the Shift
key down, then the insertion cursor moves and the selection is
extended to include the new character. Control-Left and Control-
Right move the insertion cursor by words, and Control-Shift-Left
and Control-Shift-Right move the insertion cursor by words and also
extend the selection. Control-b and Control-f behave the same as
Left and Right, respectively. Meta-b and Meta-f behave the same as
Control-Left and Control-Right, respectively.
[10]
The Home key, or Control-a, will move the insertion cursor to the
beginning of the entry and clear any selection in the entry.
Shift-Home moves the insertion cursor to the beginning of the entry
and also extends the selection to that point.
[11]
The End key, or Control-e, will move the insertion cursor to the
end of the entry and clear any selection in the entry. Shift-End
moves the cursor to the end and extends the selection to that
point.
[12]
The Select key and Control-Space set the selection anchor to the
position of the insertion cursor. They don't affect the current
selection. Shift-Select and Control-Shift-Space adjust the
selection to the current position of the insertion cursor,
selecting from the anchor to the insertion cursor if there was not
any selection previously.
[13]
Control-/ selects all the text in the entry.
[14]
Control-\ clears any selection in the entry.
[15]
The F16 key (labelled Copy on many Sun workstations) or Meta-w
copies the selection in the widget to the clipboard, if there is a
selection.
[16]
The F20 key (labelled Cut on many Sun workstations) or Control-w
copies the selection in the widget to the clipboard and deletes the
selection. If there is no selection in the widget then these keys
have no effect.
[17]
The F18 key (labelled Paste on many Sun workstations) or Control-y
inserts the contents of the clipboard at the position of the
insertion cursor.
[18]
The Delete key deletes the selection, if there is one in the entry.
If there is no selection, it deletes the character to the right of
the insertion cursor.
[19]
The BackSpace key and Control-h delete the selection, if there is
one in the entry. If there is no selection, it deletes the
character to the left of the insertion cursor.
[20]
Control-d deletes the character to the right of the insertion
cursor.
[21]
Meta-d deletes the word to the right of the insertion cursor.
[22]
Control-k deletes all the characters to the right of the insertion
cursor.
[23]
Control-t reverses the order of the two characters to the right of
the insertion cursor.
If the entry is disabled using the -state option, then the entry's
view can still be adjusted and text in the entry can still be
selected, but no insertion cursor will be displayed and no text
modifications will take place.
The behavior of entries can be changed by defining new bindings for
individual widgets or by redefining the class bindings.
KEYWORDS
entry, widget
perl v5.26.0 2017-07-22 Entry(3pm)
