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diff --git a/man/9/scrollbar b/man/9/scrollbar new file mode 100644 index 00000000..b7fe9ea4 --- /dev/null +++ b/man/9/scrollbar @@ -0,0 +1,252 @@ +.TH SCROLLBAR 9 +.SH NAME +scrollbar \- 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\fP +Specifies the relief to use when displaying the element that is +active, if any. +Elements other than the active element are always displayed with +a raised relief. +.TP +.B -command \fIcommand\fP +Specifies the prefix of a Tk command to invoke to change the view +in the widget associated with the scrollbar. When a user requests +a view change by manipulating the scrollbar, a Tk command is +invoked. The actual command consists of this option followed by +additional information as described later. This option almost always has +a value such as \f5.t xview\fR or \f5.t yview\fR, consisting of the +name of a widget and either \f5xview\fR (if the scrollbar is for +horizontal scrolling) or \f5yview\fR (for vertical scrolling). +All scrollable widgets have \f5xview\fR and \f5yview\fR commands +that take exactly the additional arguments appended by the scrollbar +as described in SCROLLING COMMANDS below. +.ig +DEPRECATED +.TP +.B -elementborderwidth \fIdist\fP +Specifies the width of borders drawn around the internal elements +of the scrollbar (the two arrows and the slider). +If this value is less than zero, the value of the \f5borderwidth\fR +option is used in its place. +.. +.TP +.B -height \fIdist\fP +Specifies a desired height for the scrollbar. +If this option isn't specified, a suitable default height is chosen. +.TP +.B -width \fIdist\fP +Specifies a desired width for the scrollbar. +If this option isn't specified, a suitable default width is chosen. +.SH DESCRIPTION +The \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 command +line to configure aspects of the scrollbar +such 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 window +named \fIpathName\fR. +.PP +A scrollbar is a widget that displays two arrows, one at each end of +the scrollbar, and a \fIslider\fR in the middle portion of the +scrollbar. +It provides information about what is visible in an \fIassociated window\fR +that displays a document of some sort (such as a file being edited or +a drawing). +The position and size of the slider indicate which portion of the +document is visible in the associated window. For example, if the +slider in a vertical scrollbar covers the top third of the area +between the two arrows, it means that the associated window displays +the top third of its document. +.PP +Scrollbars can be used to adjust the view in the associated window +by clicking or dragging with the mouse. See the BINDINGS section +below for details. + +.SH ELEMENTS +A scrollbar displays five elements, which are referred to in the +widget commands for the scrollbar: +.TP 12 +\f5arrow1\fR +The top or left arrow in the scrollbar. +.TP 12 +\f5trough1\fR +The region between the slider and \f5arrow1\fR. +.TP 12 +\f5slider\fR +The rectangle that indicates what is visible in the associated widget. +.TP 12 +\f5trough2\fR +The region between the slider and \f5arrow2\fR. +.TP 12 +\f5arrow2\fR +The bottom or right arrow in the scrollbar. + +.SH "WIDGET COMMAND" +The \f5scrollbar\fR command creates a new Tk command whose +name is \fIpathName\fR. This +command may be used to invoke various +operations on the widget. It has the following general form: +.RS +.EX +\fIpathName option \fR?\fIarg arg ...\fR? +.EE +.RE +\fIOption\fR and the \fIarg\fRs +determine the exact behaviour of the command. The following +commands are possible for scrollbar widgets: +.TP +\fIpathName \f5activate \fR?\fIelement\fR? +Marks the element indicated by \fIelement\fR as active, which +causes 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 scrollbar +will be active. +If \fIelement\fR is not specified, the command returns +the name of the element that is currently active, or an empty string +if no element is active. +.TP +\fIpathName \f5cget\fR \fIoption\fR +Returns the current value of the configuration option given +by \fIoption\fR. +\fIOption\fR may have any of the values accepted by the \f5scrollbar\fR +command. +.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 of +the available options for \fIpathName\fR. If +one or more \fIoption-value\fR 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. +\fIOption\fR may have any of the values accepted by the \f5scrollbar\fR +command. +.TP +\fIpathName \f5delta \fIdeltaX deltaY\fR +Returns a real number indicating the fractional change in +the scrollbar setting that corresponds to a given change +in slider position. For example, if the scrollbar is horizontal, +the result indicates how much the scrollbar setting must change +to move the slider \fIdeltaX\fR pixels to the right (\fIdeltaY\fR is +ignored in this case). +If the scrollbar is vertical, the result indicates how much the +scrollbar setting must change to move the slider \fIdeltaY\fR pixels +down. The arguments and the result may be zero or negative. +.TP +\fIpathName \f5fraction \fIx y\fR +Returns a real number between 0 and 1 indicating where the point +given 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, the +value 1 corresponds to the bottom or right, 0.5 corresponds to +the middle, and so on. +\fIX\fR and \fIy\fR must be pixel coordinates relative to the scrollbar +widget. +If \fIx\fR and \fIy\fR refer to a point outside the trough, the closest +point in the trough is used. +.TP +\fIpathName \f5get\fR +Returns the scrollbar settings in the form of a list whose +elements are the arguments to the most recent \f5set\fR widget command. +.TP +\fIpathName \f5identify\fR \fIx y\fR +Returns 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 does +not lie in any element of the scrollbar. +\fIX\fR and \fIy\fR must be pixel coordinates relative to the scrollbar +widget. +.TP +\fIpathName \f5set\fR \fIfirst last\fR +This command is invoked by the scrollbar's associated widget to +tell the scrollbar about the current view in the widget. +The command takes two arguments, each of which is a real fraction +between 0 and 1. +The fractions describe the range of the document that is visible in +the associated widget. +For example, if \fIfirst\fR is 0.2 and \fIlast\fR is 0.4, it means +that 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 dragging +the slider, the scrollbar notifies the associated widget that it +must change its view. +The scrollbar makes the notification by evaluating a Tk command +generated 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 given +by \fIfraction\fR appears at the beginning of the widget. +If \fIfraction\fR is 0 it refers to the beginning of the +document. 1.0 refers to the end of the document, 0.333 +refers to a point one-third of the way through the document, +and so on. +.TP +\fIprefix \f5scroll \fInumber \f5unit\fR +The 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 off +the top or left of the window, or -1, which means that one unit +should scroll off the bottom or right of the window. +.TP +\fIprefix \f5scroll \fInumber \f5page\fR +The widget should adjust its view by \fInumber\fR pages. +It is up to the widget to define the meaning of a page; typically +it is slightly less than what fits in the window, so that there +is a slight overlap between the old and new views. +\fINumber\fR is either 1, which means the next page should +become visible, or -1, which means that the previous page should +become visible. + +.SH BINDINGS +Tk automatically creates bindings for scrollbars that give them +the 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 the +associated widget to shift up (left) by one unit so that the +document 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 the +associated widget to shift up (left) by one screenful so that the +document appears to move down (right) one screenful. +.IP [3] +Pressing button 1 over the slider and dragging causes the view +to drag with the slider. +If the \f5jump\fR option is true, then the view doesn't drag along +with the slider; it changes only when the mouse button is released. +.IP [4] +Pressing button 1 over \f5trough2\fR causes the view in the +associated widget to shift down (right) by one screenful so that the +document appears to move up (left) one screenful. +.IP [5] +Pressing button 1 over \f5arrow2\fR causes the view in the +associated widget to shift down (right) by one unit so that the +document 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 sets +the view to correspond to the mouse position; dragging the +mouse with button 2 down causes the view to drag with the mouse. +If button 2 is pressed over one of the arrows, it causes the +same behaviour as pressing button 1. +.SH SEE ALSO +.IR options (9), +.IR types (9) |
