BUTTON(9)                                               BUTTON(9)

     NAME
          button - Create and manipulate button widgets

     SYNOPSIS
          button pathName ?options?

     STANDARD OPTIONS
          -activebackground -disabledcolor      -justify
          -activeforeground -font               -relief
          -anchor           -foreground         -takefocus
          -background       -highlightcolor     -text
          -bitmap           -highlightthickness -underline
          -borderwidth      -image

     WIDGET-SPECIFIC OPTIONS
          -command tkcmd
               Specifies a Tk command to associate with the button.
               This command is typically invoked when mouse button 1
               is released over the button window.

          -height dist
               Specifies a desired height for the button.  If this
               option isn't specified, the button's desired height is
               computed from the size of the image or bitmap or text
               being displayed in it.

          -state state
               Specifies one of three states for the button:  normal,
               active, or disabled.  In normal state the button is
               displayed using the foreground and background options.
               The active state is typically used when the pointer is
               over the button.  In active state the button is dis-
               played using the activeForeground and activeBackground
               options.  Disabled state means that the button should
               be insensitive:  the default bindings will refuse to
               activate the widget and will ignore mouse button
               presses.  In this state the background option deter-
               mines how the button is displayed.

          -width dist
               Specifies a desired width for the button.  If this
               option isn't specified, the button's desired width is
               computed from the size of the image or bitmap or text
               being displayed in it.

     DESCRIPTION
          The button command creates a new window (given by the path-
          Name argument) and makes it into a button widget.  Addi-
          tional options, described above, may be specified on the
          command line.  to configure aspects of the button such as

     BUTTON(9)                                               BUTTON(9)

          its colours, font, text, and initial relief.  The button
          command returns its pathName argument.  At the time this
          command is invoked, there must not exist a window named
          pathName.

          A button is a widget that displays a textual string, bitmap
          or image.  If text is displayed, it must all be in a single
          font, but it can occupy multiple lines on the screen (if it
          contains newlines) and one of the characters may optionally
          be underlined using the underline option.  It can display
          itself in either of three different ways, according to the
          state option; it can be made to appear raised, sunken, or
          flat.  When a user invokes the button (by pressing mouse
          button 1 with the cursor over the button), then the Tk com-
          mand specified in the -command option is invoked.

     WIDGET COMMAND
          The button command creates a new Tk command whose name is
          pathName.  This command may be used to invoke various opera-
          tions on the widget.  It has the following general form:
               pathName option ?arg arg ...?
          Option and the args determine the exact behaviour of the
          command.  The following commands are possible for button
          widgets:

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

          pathName configure ?option? ?value option value ...?
               Query or modify the configuration options of the wid-
               get.  If no option is specified, returns a list of all
               of the available options for pathName. If one or more
               option-value pairs are specified, then the command mod-
               ifies 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 button command.

          pathName invoke
               Invoke the Tk command associated with the button, if
               there is one.  The return value is the return value
               from the Tk command, or an empty string if there is no
               command associated with the button.  This command is
               ignored if the button's state is disabled.

     DEFAULT BINDINGS
          Tk automatically creates bindings for buttons that give them
          the following default behaviour:

     BUTTON(9)                                               BUTTON(9)

          [1]  A button activates whenever the mouse passes over it
               and deactivates whenever the mouse leaves the button.

          [2]  A button's relief is changed to sunken whenever mouse
               button 1 is pressed over the button, and the relief is
               restored to its original value when button 1 is later
               released.

          [3]  If mouse button 1 is pressed over a button and later
               released over the button, the button is invoked.  How-
               ever, if the mouse is not over the button when button 1
               is released, then no invocation occurs.

          [4]  If the Enter or Space key is pressed when the button
               has keyboard focus, the button is invoked.

          If the button's state is disabled then none of the above
          actions occur:  the button is completely non-responsive.

          The behaviour of buttons can be changed by defining new
          bindings for individual widgets.

     SEE ALSO
          checkbutton(9), choicebutton(9), options(9), radiobutton(9),
          types(9)