ttk::entry − Editable text field widget


ttk::entry pathName ?options? ___________________________


An ttk::entry widget displays a one-line text string and allows that string to be edited by the user. The value of the string may be linked to a Tcl variable with the −textvariable option. Entry widgets support horizontal scrolling with the standard −xscrollcommand option and xview widget command.







See the ttk_widget manual entry for details on the standard options.


Command-Line Name:−exportselection

Database Name:


Database Class:


A boolean value specifying whether or not a selection in the widget should be linked to the X selection. If the selection is exported, then selecting in the widget deselects the current X selection, selecting outside the widget deselects any widget selection, and the widget will respond to selection retrieval requests when it has a selection.

Command-Line Name:−invalidcommand

Database Name:


Database Class:


A script template to evaluate whenever the −validatecommand returns 0. See VALIDATION below for more information.

Command-Line Name:−justify

Database Name:


Database Class:


Specifies how the text is aligned within the entry widget. One of left, center, or right.

Command-Line Name:−show

Database Name:


Database Class:


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 “*” or a bullet. 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.

Command-Line Name:−state

Database Name:


Database Class:


Compatibility option; see ttk::widget(n) for details. Specifies one of three states for the entry, normal, disabled, or readonly. See WIDGET STATES, below.

Command-Line Name:−textvariable

Database Name:


Database Class:


Specifies the name of a global variable whose value is linked to the entry widget’s contents. Whenever the variable changes value, the widget’s contents are updated, and vice versa.

Command-Line Name:−validate

Database Name:


Database Class:


Specifies the mode in which validation should operate: none, focus, focusin, focusout, key, or all. Default is none, meaning that validation is disabled. See VALIDATION below.

Command-Line Name:−validatecommand

Database Name:


Database Class:


A script template to evaluate whenever validation is triggered. If set to the empty string (the default), validation is disabled. The script must return a boolean value. See VALIDATION below.

Command-Line Name:−width

Database Name:


Database Class:


Specifies an integer value indicating the desired width of the entry window, in average-size characters of the widget’s font.


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 insert 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; commands 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).


Many of the entry widget commands take one or more indices as arguments. An index specifies a particular character in the entry’s string, in any of the following ways:


Specifies the character as a numerical index, where 0 corresponds to the first character in the string.


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.


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.


Indicates the character adjacent to and immediately following the insert cursor.


Indicates the first character in the selection. It is an error to use this form if the selection is not in the entry window.


Indicates the character just after the last one in the selection. It is an error to use this form if the selection is not in the entry window.

Abbreviations may be used for any of the forms above, e.g. “e” or “sel.l”. In general, out-of-range indices are automatically rounded to the nearest legal value.


The following subcommands are possible for entry widgets:
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.

pathName 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 is not specified it defaults to first+1, i.e. a single character is deleted. This command returns the empty string.

pathName get

Returns the entry’s string.

pathName icursor index

Arrange for the insert cursor to be displayed just before the character given by index. Returns the empty string.

pathName index index

Returns the numerical index corresponding to index.

pathName insert index string

Insert string just before the character indicated by index. Returns the empty string.

pathName selection option arg

This command is used to adjust the selection within an entry. It has several forms, depending on option:
selection clear

Clear the selection if it is currently in this widget. If the selection is not in this widget then the command has no effect. Returns the empty string.

pathName selection present

Returns 1 if there is are characters selected in the entry, 0 if nothing is selected.

pathName selection range 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.

pathName validate

Force revalidation, independent of the conditions specified by the −validate option. Returns 0 if validation fails, 1 if it succeeds. Sets or clears the invalid state accordingly. See VALIDATION below for more details.

pathName 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:

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 .6, 20% of the entry’s text is off-screen to the left, the middle 40% is visible in the window, and 40% of the text is off-screen to the right. These are the same values passed to scrollbars via the −xscrollcommand option.

pathName xview index

Adjusts the view in the window so that the character given by index is displayed at the left edge of the window.

pathName xview moveto 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.

pathName xview scroll number what

This command 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. 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.

The entry widget also supports the following generic ttk::widget widget subcommands (see ttk::widget(n) for details):

cget configure identify




The −validate, −validatecommand, and −invalidcommand options are used to enable entry widget validation.

There are two main validation modes: prevalidation, in which the −validatecommand is evaluated prior to each edit and the return value is used to determine whether to accept or reject the change; and revalidation, in which the −validatecommand is evaluated to determine whether the current value is valid.

The −validate option determines when validation occurs; it may be set to any of the following values:


Default. This means validation will only occur when specifically requested by the validate widget command.


The entry will be prevalidated prior to each edit (specifically, whenever the insert or delete widget commands are called). If prevalidation fails, the edit is rejected.


The entry is revalidated when the entry receives or loses focus.


The entry is revalidated when the entry receives focus.


The entry is revalidated when the entry loses focus.


Validation is performed for all above conditions.

The −invalidcommand is evaluated whenever the −validatecommand returns a false value.

The −validatecommand and −invalidcommand may modify the entry widget’s value via the widget insert or delete commands, or by setting the linked −textvariable. If either does so during prevalidation, then the edit is rejected regardless of the value returned by the −validatecommand.

If −validatecommand is empty (the default), validation always succeeds.

It is possible to perform percent substitutions on the −validatecommand and −invalidcommand, just as in a bind script. The following substitutions are recognized:


Type of action: 1 for insert prevalidation, 0 for delete prevalidation, or −1 for revalidation.


Index of character string to be inserted/deleted, if any, otherwise −1.


In prevalidation, the new value of the entry if the edit is accepted. In revalidation, the current value of the entry.


The current value of entry prior to editing.


The text string being inserted/deleted, if any, {} otherwise.


The current value of the −validate option.


The validation condition that triggered the callback (key, focusin, focusout, or forced).


The name of the entry widget.

The standard Tk entry widget automatically disables validation (by setting −validate to none) if the −validatecommand or −invalidcommand modifies the entry’s value. The Tk themed entry widget only disables validation if one of the validation scripts raises an error, or if −validatecommand does not return a valid boolean value. (Thus, it is not necessary to re-enable validation after modifying the entry value in a validation script).

In addition, the standard entry widget invokes validation whenever the linked −textvariable is modified; the Tk themed entry widget does not.


The entry widget’s default bindings enable the following behavior. In the descriptions below, “word” refers to a contiguous group of letters, digits, or “_” characters, or any single character other than these.

Clicking mouse button 1 positions the insert 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 down strokes out a selection between the insert cursor and the character under the mouse.

Double-clicking with mouse button 1 selects the word under the mouse and positions the insert cursor at the end of the word. Dragging after a double click strokes out a selection consisting of whole words.

Triple-clicking with mouse button 1 selects all of the text in the entry and positions the insert cursor at the end of the line.

The ends of the selection can be adjusted by dragging with mouse button 1 while the Shift key is down. If the button is double-clicked before dragging then the selection will be adjusted in units of whole words.

Clicking mouse button 1 with the Control key down will position the insert cursor in the entry without affecting the selection.

If any normal printing characters are typed in an entry, they are inserted at the point of the insert cursor.

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.

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).

The Left and Right keys move the insert cursor one character to the left or right; they also clear any selection in the entry. 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 insert cursor by words, and Control-Shift-Left and Control-Shift-Right move the insert cursor by words and also extend the selection. Control-b and Control-f behave the same as Left and Right, respectively.

The Home key and Control-a move the insert cursor to the beginning of the entry and clear any selection in the entry. Shift-Home moves the insert cursor to the beginning of the entry and extends the selection to that point.

The End key and Control-e move the insert 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.

Control-/ selects all the text in the entry.

Control-\ clears any selection in the entry.

The standard Tk <<Cut>>, <<Copy>>, <<Paste>>, and <<Clear>> virtual events operate on the selection in the expected manner.

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 insert cursor.

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 insert cursor.

Control-d deletes the character to the right of the insert cursor.

Control-k deletes all the characters to the right of the insertion cursor.


In the disabled state, the entry cannot be edited and the text cannot be selected. In the readonly state, no insert cursor is displayed and the entry cannot be edited (specifically: the insert and delete commands have no effect). The disabled state is the same as readonly, and in addition text cannot be selected.

Note that changes to the linked −textvariable will still be reflected in the entry, even if it is disabled or readonly.

Typically, the text is “grayed-out” in the disabled state, and a different background is used in the readonly state.

The entry widget sets the invalid state if revalidation fails, and clears it whenever validation succeeds.


ttk::widget(n), entry(n)


entry, widget, text field


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