.TH SCROLLBAR 9.SH NAMEscrollbar \- Create and manipulate scrollbar widgets.SH SYNOPSIS\f5scrollbar\fI pathName \fR?\fIoptions\fR?.SH STANDARD OPTIONS.EX-activebackground -borderwidth      -orient-background       -jump             -relief.EE.SH "WIDGET-SPECIFIC OPTIONS".TP.B -activerelief \fIrelief\fPSpecifies the relief to use when displaying the element that isactive, if any.Elements other than the active element are always displayed witha raised relief..TP.B -command \fIcommand\fPSpecifies the prefix of a Tk command to invoke to change the viewin the widget associated with the scrollbar.  When a user requestsa view change by manipulating the scrollbar, a Tk command isinvoked.  The actual command consists of this option followed byadditional information as described later.  This option almost always hasa value such as \f5.t xview\fR or \f5.t yview\fR, consisting of thename of a widget and either \f5xview\fR (if the scrollbar is forhorizontal scrolling) or \f5yview\fR (for vertical scrolling).All scrollable widgets have \f5xview\fR and \f5yview\fR commandsthat take exactly the additional arguments appended by the scrollbaras described in SCROLLING COMMANDS below..igDEPRECATED.TP.B -elementborderwidth \fIdist\fPSpecifies the width of borders drawn around the internal elementsof the scrollbar (the two arrows and the slider).If this value is less than zero, the value of the \f5borderwidth\fRoption is used in its place....TP.B -height \fIdist\fPSpecifies a desired height for the scrollbar.If this option isn't specified, a suitable default height is chosen..TP.B -width \fIdist\fPSpecifies a desired width for the scrollbar.If this option isn't specified, a suitable default width is chosen..SH DESCRIPTIONThe \f5scrollbar\fR command creates a new window (given by the\fIpathName\fR argument) and makes it into a scrollbar widget.Additional options, described above, may be specified on the commandline to configure aspects of the scrollbarsuch as its colours, orientation, and relief.The \f5scrollbar\fR command returns its \fIpathName\fR argument.At the time this command is invoked, there must not exist a windownamed \fIpathName\fR..PPA scrollbar is a widget that displays two arrows, one at each end ofthe scrollbar, and a \fIslider\fR in the middle portion of thescrollbar.It provides information about what is visible in an \fIassociated window\fRthat displays a document of some sort (such as a file being edited ora drawing).The position and size of the slider indicate which portion of thedocument is visible in the associated window.  For example, if theslider in a vertical scrollbar covers the top third of the areabetween the two arrows, it means that the associated window displaysthe top third of its document..PPScrollbars can be used to adjust the view in the associated windowby clicking or dragging with the mouse.  See the BINDINGS sectionbelow for details. .SH ELEMENTSA scrollbar displays five elements, which are referred to in thewidget commands for the scrollbar:.TP 12\f5arrow1\fRThe top or left arrow in the scrollbar..TP 12\f5trough1\fRThe region between the slider and \f5arrow1\fR..TP 12\f5slider\fRThe rectangle that indicates what is visible in the associated widget..TP 12\f5trough2\fRThe region between the slider and \f5arrow2\fR..TP 12\f5arrow2\fRThe bottom or right arrow in the scrollbar. .SH "WIDGET COMMAND"The \f5scrollbar\fR command creates a new Tk command whosename is \fIpathName\fR.  Thiscommand may be used to invoke variousoperations on the widget.  It has the following general form:.RS.EX\fIpathName option \fR?\fIarg arg ...\fR?.EE.RE\fIOption\fR and the \fIarg\fRsdetermine the exact behaviour of the command.  The followingcommands are possible for scrollbar widgets:.TP\fIpathName \f5activate \fR?\fIelement\fR?Marks the element indicated by \fIelement\fR as active, whichcauses it to be displayed as specified by the \f5activebackground\fR option.The only element values understood by this command are \f5arrow1\fR,\f5slider\fR, or \f5arrow2\fR.If any other value is specified then no element of the scrollbarwill be active.If \fIelement\fR is not specified, the command returnsthe name of the element that is currently active, or an empty stringif no element is active..TP\fIpathName \f5cget\fR \fIoption\fRReturns the current value of the configuration option givenby \fIoption\fR.\fIOption\fR may have any of the values accepted by the \f5scrollbar\fRcommand..TP\fIpathName \f5configure\fR ?\fIoption\fR? ?\fIvalue option value ...\fR?Query or modify the configuration options of the widget.If no \fIoption\fR is specified, returns a list of all ofthe available options for \fIpathName\fR.  Ifone or more \fIoption-value\fR pairs are specified, then the commandmodifies the given widget option(s) to have the given value(s);  inthis case the command returns an empty string.\fIOption\fR may have any of the values accepted by the \f5scrollbar\fRcommand..TP\fIpathName \f5delta \fIdeltaX deltaY\fRReturns a real number indicating the fractional change inthe scrollbar setting that corresponds to a given changein slider position.  For example, if the scrollbar is horizontal,the result indicates how much the scrollbar setting must changeto move the slider \fIdeltaX\fR pixels to the right (\fIdeltaY\fR isignored in this case).If the scrollbar is vertical, the result indicates how much thescrollbar setting must change to move the slider \fIdeltaY\fR pixelsdown.  The arguments and the result may be zero or negative..TP\fIpathName \f5fraction \fIx y\fRReturns a real number between 0 and 1 indicating where the pointgiven by \fIx\fR and \fIy\fR lies in the trough area of the scrollbar.The value 0 corresponds to the top or left of the trough, thevalue 1 corresponds to the bottom or right, 0.5 corresponds tothe middle, and so on.\fIX\fR and \fIy\fR must be pixel coordinates relative to the scrollbarwidget.If \fIx\fR and \fIy\fR refer to a point outside the trough, the closestpoint in the trough is used..TP\fIpathName \f5get\fRReturns the scrollbar settings in the form of a list whoseelements are the arguments to the most recent \f5set\fR widget command..TP\fIpathName \f5identify\fR \fIx y\fRReturns the name of the element under the point given by \fIx\fR and\fIy\fR (such as \f5arrow1\fR), or an empty string if the point doesnot lie in any element of the scrollbar.\fIX\fR and \fIy\fR must be pixel coordinates relative to the scrollbarwidget..TP\fIpathName \f5set\fR \fIfirst last\fRThis command is invoked by the scrollbar's associated widget totell the scrollbar about the current view in the widget.The command takes two arguments, each of which is a real fractionbetween 0 and 1.The fractions describe the range of the document that is visible inthe associated widget.For example, if \fIfirst\fR is 0.2 and \fIlast\fR is 0.4, it meansthat the first part of the document visible in the window is 20%of the way through the document, and the last visible part is 40%of the way through. .SH "SCROLLING COMMANDS"When the user interacts with the scrollbar, for example by draggingthe slider, the scrollbar notifies the associated widget that itmust change its view.The scrollbar makes the notification by evaluating a Tk commandgenerated from the scrollbar's \f5-command\fR option.The command may take any of the following forms.In each case, \fIprefix\fR is the contents of the\f5-command\fR option, which usually has a form like \f5.t yview\fR.TP\fIprefix \f5moveto \fIfraction\fR\fIFraction\fR is a real number between 0 and 1.The widget should adjust its view so that the point givenby \fIfraction\fR appears at the beginning of the widget.If \fIfraction\fR is 0 it refers to the beginning of thedocument.  1.0 refers to the end of the document, 0.333refers to a point one-third of the way through the document,and so on..TP\fIprefix \f5scroll \fInumber \f5unit\fRThe widget should adjust its view by \fInumber\fR units.The units are defined in whatever way makes sense for the widget,such as characters or lines in a text widget.\fINumber\fR is either 1, which means one unit should scroll offthe top or left of the window, or -1, which means that one unitshould scroll off the bottom or right of the window..TP\fIprefix \f5scroll \fInumber \f5page\fRThe widget should adjust its view by \fInumber\fR pages.It is up to the widget to define the meaning of a page;  typicallyit is slightly less than what fits in the window, so that thereis a slight overlap between the old and new views.\fINumber\fR is either 1, which means the next page shouldbecome visible, or -1, which means that the previous page shouldbecome visible. .SH BINDINGSTk automatically creates bindings for scrollbars that give themthe following default behaviour.If the behaviour is different for vertical and horizontal scrollbars,the horizontal behaviour is described in parentheses. .IP [1]Pressing button 1 over \f5arrow1\fR causes the view in theassociated widget to shift up (left) by one unit so that thedocument appears to move down (right) one unit.If the button is held down, the action auto-repeats..IP [2]Pressing button 1 over \f5trough1\fR causes the view in theassociated widget to shift up (left) by one screenful so that thedocument appears to move down (right) one screenful..IP [3]Pressing button 1 over the slider and dragging causes the viewto drag with the slider.If the \f5jump\fR option is true, then the view doesn't drag alongwith the slider;  it changes only when the mouse button is released..IP [4]Pressing button 1 over \f5trough2\fR causes the view in theassociated widget to shift down (right) by one screenful so that thedocument appears to move up (left) one screenful..IP [5]Pressing button 1 over \f5arrow2\fR causes the view in theassociated widget to shift down (right) by one unit so that thedocument appears to move up (left) one unit.If the button is held down, the action auto-repeats..IP [6]If button 2 is pressed over the trough or the slider, it setsthe view to correspond to the mouse position;  dragging themouse with button 2 down causes the view to drag with the mouse.If button 2 is pressed over one of the arrows, it causes thesame behaviour as pressing button 1..SH SEE ALSO.IR options (9),.IR types (9)