listbox(n) Tk Built-In Commands listbox(n) 







listbox - Create and manipulate listbox widgets








listbox pathName ?options?








-background	-borderwidth	-cursor
-disabledforeground	-exportselection	-font
-foreground	-highlightbackground	-highlightcolor
-highlightthickness	-relief	-selectbackground
-selectborderwidth	-selectforeground	-setgrid
-takefocus	-xscrollcommand	-yscrollcommand


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








[-activestyle activeStyle]
    Specifies the style in which to draw the active element. This must be one of
    dotbox (show a focus ring around the active element), none (no
    special indication of active element) or underline (underline the
    active element). The default is underline on Windows, and
    dotbox elsewhere. [-height
    height] Specifies the desired height for the window, in lines.
    If zero or less, then the desired height for the window is made just large
    enough to hold all the elements in the listbox.
    [-listvariable listVariable] Specifies
    the name of a variable. The value of the variable is a list to be displayed
    inside the widget; if the variable value changes then the widget will
    automatically update itself to reflect the new value. Attempts to assign a
    variable with an invalid list value to -listvariable will cause an
    error. Attempts to unset a variable in use as a -listvariable will
    fail but will not generate an error. [-selectmode
    selectMode] Specifies one of several styles for manipulating
    the selection. The value of the option may be arbitrary, but the default
    bindings expect it to be either single, browse,
    multiple, or extended; the default value is browse.
    [-state state] Specifies one of two
    states for the listbox: normal or disabled. If the listbox is
    disabled then items may not be inserted or deleted, items are drawn in the
    -disabledforeground color, and selection cannot be modified and is
    not shown (though selection information is retained).
    [-width width] Specifies the desired
    width for the window in characters. If the font does not have a uniform
    width then the width of the character “0” is used in
    translating from character units to screen units. If zero or less, then the
    desired width for the window is made just large enough to hold all the
    elements in the listbox.










The listbox command creates a new window (given by the
    pathName argument) and makes it into a listbox widget. Additional
    options, described above, may be specified on the command line or in the
    option database to configure aspects of the listbox such as its colors,
    font, text, and relief. The listbox command returns its
    pathName argument. At the time this command is invoked, there must
    not exist a window named pathName, but pathName's parent must
    exist.


A listbox is a widget that displays a list of strings, one per
    line. When first created, a new listbox has no elements. Elements may be
    added or deleted using widget commands described below. In addition, one or
    more elements may be selected as described below. If a listbox is exporting
    its selection (see exportSelection option), then it will observe the
    standard X11 protocols for handling the selection. Listbox selections are
    available as type STRING; the value of the selection will be the text
    of the selected elements, with newlines separating the elements.


It is not necessary for all the elements to be displayed in the
    listbox window at once; commands described below may be used to change the
    view in the window. Listboxes allow scrolling in both directions using the
    standard xScrollCommand and yScrollCommand options. They also
    support scanning, as described below.








Many of the widget commands for listboxes take one or more indices
    as arguments. An index specifies a particular element of the listbox, in any
    of the following ways:



  

  
Specifies the element as a numerical index, where 0 corresponds to the
      first element in the listbox.

  

  
Indicates the element that has the location cursor. This element will be
      displayed as specified by -activestyle when the listbox has the
      keyboard focus, and it is specified with the activate widget
      command.

  

  
Indicates the anchor point for the selection, which is set with the
      selection anchor widget command.

  

  
Indicates the end of the listbox. For most commands this refers to the
      last element in the listbox, but for a few commands such as index
      and insert it refers to the element just after the last one.

  
@x,y

  
Indicates the element that covers the point in the listbox window
      specified by x and y (in pixel coordinates). If no element
      covers that point, then the closest element to that point is used.




In the widget command descriptions below, arguments named
    index, first, and last always contain text indices in
    one of the above forms.








The listbox command creates a new Tcl command whose name is
    pathName. This command may be used to invoke various operations on
    the widget. It has the following general form:




pathName option ?arg arg ...?



Option and the args determine the exact behavior of the command.
  The following commands are possible for listbox widgets:


  

  
Sets the active element to the one indicated by index. If
      index is outside the range of elements in the listbox then the
      closest element is activated. The active element is drawn as specified by
      -activestyle when the widget has the input focus, and its index may
      be retrieved with the index active.

  

  
Returns a list of four numbers describing the bounding box of the text in
      the element 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 text (specified in pixels relative to the widget) and the
      last two elements give the width and height of the area, in pixels. If no
      part of the element given by index is visible on the screen, or if
      index refers to a non-existent element, then the result is an empty
      string; if the element is partially visible, the result gives the full
      area of the element, including any parts that are not visible.

  

  
Returns the current value of the configuration option given by
      option. Option may have any of the values accepted by the
      listbox command.

  

  
Query or modify the configuration options of the widget. If no
      option is specified, returns a list describing all of the available
      options for pathName (see Tk_ConfigureInfo 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 listbox command.

  

  
Returns a list containing the numerical indices of all of the elements in
      the listbox that are currently selected. If there are no elements selected
      in the listbox then an empty string is returned.

  

  
Deletes one or more elements of the listbox. First and last
      are indices specifying the first and last elements in the range to delete.
      If last is not specified it defaults to first, i.e. a single
      element is deleted.

  

  
If last is omitted, returns the contents of the listbox element
      indicated by first, or an empty string if first refers to a
      non-existent element. If last is specified, the command returns a
      list whose elements are all of the listbox elements between first
      and last, inclusive. Both first and last may have any
      of the standard forms for indices.

  

  
Returns the integer index value that corresponds to index. If
      index is end the return value is a count of the number of
      elements in the listbox (not the index of the last element).

  

  
Inserts zero or more new elements in the list just before the element
      given by index. If index is specified as end then the
      new elements are added to the end of the list. Returns an empty
    string.

  

  
Returns the current value of the item configuration option given by
      option. Option may have any of the values accepted by the
      listbox itemconfigure command.

  

  
Query or modify the configuration options of an item in the listbox. If no
      option is specified, returns a list describing all of the available
      options for the item (see Tk_ConfigureInfo 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. The
      following options are currently supported for items:







  

  
Color specifies the background color to use when displaying the
      item. It may have any of the forms accepted by Tk_GetColor.

  

  
Color specifies the foreground color to use when displaying the
      item. It may have any of the forms accepted by Tk_GetColor.

  

  
color specifies the background color to use when displaying the
      item while it is selected. It may have any of the forms accepted by
      Tk_GetColor.

  

  
color specifies the foreground color to use when displaying the
      item while it is selected. It may have any of the forms accepted by
      Tk_GetColor.







  

  
Given a y-coordinate within the listbox window, this command returns the
      index of the (visible) listbox element nearest to that y-coordinate.

  

  
This command is used to implement scanning on listboxes. It has two forms,
      depending on option:







  

  
Records x and y and the current view in the listbox window;
      used in conjunction with later scan dragto commands. Typically this
      command is associated with a mouse button press in the widget. It returns
      an empty string.

  

  
This command computes the difference between its x and y
      arguments and the x and y arguments to the last scan
      mark command for the widget. It then adjusts the view by 10 times the
      difference in coordinates. This command is typically associated with mouse
      motion events in the widget, to produce the effect of dragging the list at
      high speed through the window. The return value is an empty string.







  

  
Adjust the view in the listbox so that the element given by index
      is visible. If the element is already visible then the command has no
      effect; if the element is near one edge of the window then the listbox
      scrolls to bring the element into view at the edge; otherwise the listbox
      scrolls to center the element.

  

  
This command is used to adjust the selection within a listbox. It has
      several forms, depending on option:







  

  
Sets the selection anchor to the element given by index. If
      index refers to a non-existent element, then the closest element is
      used. The selection anchor is the end of the selection that is fixed while
      dragging out a selection with the mouse. The index anchor may be
      used to refer to the anchor element.

  

  
If any of the elements between first and last (inclusive)
      are selected, they are deselected. The selection state is not changed for
      elements outside this range.

  

  
Returns 1 if the element indicated by index is currently selected,
      0 if it is not.

  

  
Selects all of the elements in the range between first and
      last, inclusive, without affecting the selection state of elements
      outside that range.







  

  
Returns a decimal string indicating the total number of elements in the
      listbox.

  

  
This command is used to query and change the horizontal position of the
      information 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 listbox'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.

  

  
Adjusts the view in the window so that the character position given by
      index is displayed at the left edge of the window. Character
      positions are defined by the width of the character 0.

  

  
Adjusts the view in the window so that fraction of the total width
      of the listbox text is off-screen to the left. fraction must be a
      fraction between 0 and 1.

  

  
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 or an abbreviation
      of one of these. If what is units, the view adjusts left or
      right by number character units (the width of the 0
      character) 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.







  

  
This command is used to query and change the vertical position of the text
      in the widget's window. It can take any of the following forms:







  

  
Returns a list containing two elements, both of which are real fractions
      between 0 and 1. The first element gives the position of the listbox
      element at the top of the window, relative to the listbox as a whole (0.5
      means it is halfway through the listbox, for example). The second element
      gives the position of the listbox element just after the last one in the
      window, relative to the listbox as a whole. These are the same values
      passed to scrollbars via the -yscrollcommand option.

  

  
Adjusts the view in the window so that the element given by index
      is displayed at the top of the window.

  

  
Adjusts the view in the window so that the element given by
      fraction appears at the top of the window. Fraction is a
      fraction between 0 and 1; 0 indicates the first element in the listbox,
      0.33 indicates the element one-third the way through the listbox, and so
      on.

  

  
This command adjusts the view in the window up or down according to
      number and what. Number must be an integer.
      What must be either units or pages. If what is
      units, the view adjusts up or down by number lines; if it is
      pages then the view adjusts by number screenfuls. If
      number is negative then earlier elements become visible; if it is
      positive then later elements become visible.












Tk automatically creates class bindings for listboxes that give
    them Motif-like behavior. Much of the behavior of a listbox is determined by
    its selectMode option, which selects one of four ways of dealing with
    the selection.


If the selection mode is single or browse, at most
    one element can be selected in the listbox at once. In both modes, clicking
    button 1 on an element selects it and deselects any other selected item. In
    browse mode it is also possible to drag the selection with button 1.
    On button 1, the listbox will also take focus if it has a normal
    state and -takefocus is true.


If the selection mode is multiple or extended, any
    number of elements may be selected at once, including discontiguous ranges.
    In multiple mode, clicking button 1 on an element toggles its
    selection state without affecting any other elements. In extended
    mode, pressing button 1 on an element selects it, deselects everything else,
    and sets the anchor to the element under the mouse; dragging the mouse with
    button 1 down extends the selection to include all the elements between the
    anchor and the element under the mouse, inclusive.


Most people will probably want to use browse mode for
    single selections and extended mode for multiple selections; the
    other modes appear to be useful only in special situations.


Any time the selection changes in the listbox, the virtual event
    <<ListboxSelect>> will be generated. It is easiest to
    bind to this event to be made aware of any changes to listbox selection.


In addition to the above behavior, the following additional
    behavior is defined by the default bindings:



  
[1]

  
In extended mode, the selected range can be adjusted by pressing
      button 1 with the Shift key down: this modifies the selection to consist
      of the elements between the anchor and the element under the mouse,
      inclusive. The un-anchored end of this new selection can also be dragged
      with the button down.

  
[2]

  
In extended mode, pressing button 1 with the Control key down
      starts a toggle operation: the anchor is set to the element under the
      mouse, and its selection state is reversed. The selection state of other
      elements is not changed. If the mouse is dragged with button 1 down, then
      the selection state of all elements between the anchor and the element
      under the mouse is set to match that of the anchor element; the selection
      state of all other elements remains what it was before the toggle
      operation began.

  
[3]

  
If the mouse leaves the listbox window with button 1 down, the window
      scrolls away from the mouse, making information visible that used to be
      off-screen on the side of the mouse. The scrolling continues until the
      mouse re-enters the window, the button is released, or the end of the
      listbox is reached.

  
[4]

  
Mouse button 2 may be used for scanning. If it is pressed and dragged over
      the listbox, the contents of the listbox drag at high speed in the
      direction the mouse moves.

  
[5]

  
If the Up or Down key is pressed, the location cursor (active element)
      moves up or down one element. If the selection mode is browse or
      extended then the new active element is also selected and all other
      elements are deselected. In extended mode the new active element
      becomes the selection anchor.

  
[6]

  
In extended mode, Shift-Up and Shift-Down move the location cursor
      (active element) up or down one element and also extend the selection to
      that element in a fashion similar to dragging with mouse button 1.

  
[7]

  
The Left and Right keys scroll the listbox view left and right by the
      width of the character 0. Control-Left and Control-Right scroll the
      listbox view left and right by the width of the window. Control-Prior and
      Control-Next also scroll left and right by the width of the window.

  
[8]

  
The Prior and Next keys scroll the listbox view up and down by one page
      (the height of the window).

  
[9]

  
The Home and End keys scroll the listbox horizontally to the left and
      right edges, respectively.

  
[10]

  
Control-Home sets the location cursor to the first element in the listbox,
      selects that element, and deselects everything else in the listbox.

  
[11]

  
Control-End sets the location cursor to the last element in the listbox,
      selects that element, and deselects everything else in the listbox.

  
[12]

  
In extended mode, Control-Shift-Home extends the selection to the
      first element in the listbox and Control-Shift-End extends the selection
      to the last element.

  
[13]

  
In multiple mode, Control-Shift-Home moves the location cursor to
      the first element in the listbox and Control-Shift-End moves the location
      cursor to the last element.

  
[14]

  
The space and Select keys make a selection at the location cursor (active
      element) just as if mouse button 1 had been pressed over this
    element.

  
[15]

  
In extended mode, Control-Shift-space and Shift-Select extend the
      selection to the active element just as if button 1 had been pressed with
      the Shift key down.

  
[16]

  
In extended mode, the Escape key cancels the most recent selection
      and restores all the elements in the selected range to their previous
      selection state.

  
[17]

  
Control-slash selects everything in the widget, except in single
      and browse modes, in which case it selects the active element and
      deselects everything else.

  
[18]

  
Control-backslash deselects everything in the widget, except in
      browse mode where it has no effect.

  
[19]

  
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.




The behavior of listboxes can be changed by defining new bindings
    for individual widgets or by redefining the class bindings.








ttk_treeview(n)








listbox, widget







  

    8.4
    Tk