XmScrollBar(3)
NAME
XmScrollBar --- The ScrollBar widget class "XmScrollBar" "widget class" "ScrollBar"
SYNOPSIS
#include <Xm/ScrollBar.h>
DESCRIPTION
The ScrollBar widget allows the user to view data that is too large to
be displayed all at once. ScrollBars are usually located inside a
ScrolledWindow and adjacent to the widget that contains the data to be
viewed. When the user interacts with the ScrollBar, the data within the
other widget scrolls.
A ScrollBar consists of two arrows placed at each end of a rectangle.
The rectangle is called the scroll region. A smaller rectangle, called
the slider, is placed within the scroll region. The data is scrolled by
clicking either arrow, selecting on the scroll region, or dragging the
slider. When an arrow is selected, the slider within the scroll region
is moved in the direction of the arrow by an amount supplied by the
application. If the mouse button is held down, the slider continues to
move at a constant rate.
The ratio of the slider size to the scroll region size typically
corresponds to the relationship between the size of the visible data
and the total size of the data. For example, if 10 percent of the data
is visible, the slider typically occupies 10 percent of the scroll
region. This provides the user with a visual clue to the size of the
invisible data.
If the ScrollBar parent is an automatic ScrolledWindow, the
XmNtraversalOn default is True. Otherwise, the default is False.
ScrollBar holds the XmQTnavigator traits.
Classes
ScrollBar inherits behavior, resources, and traits from the Core and
XmPrimitive classes.
The class pointer is xmScrollBarWidgetClass.
The class name is XmScrollBar.
New Resources
The following table defines a set of widget resources used by the
programmer to specify data. The programmer can also set the resource
values for the inherited classes to set attributes for this widget. To
reference a resource by name or by class in a .Xdefaults file, remove
the XmN or XmC prefix and use the remaining letters. To specify one of
the defined values for a resource in a .Xdefaults file, remove the Xm
prefix and use the remaining letters (in either lowercase or uppercase,
but include any underscores between words). The codes in the access
column indicate if the given resource can be set at creation time (C),
set by using XtSetValues (S), retrieved by using XtGetValues (G), or is
not applicable (N/A).
XmScrollBar Resource Set
Name Class Type Default Access
XmNdecrementCallback XmCCallback XtCallbackList NULL C
XmNdragCallback XmCCallback XtCallbackList NULL C
XmNeditable XmCEditable Boolean True CSG
XmNincrement XmCIncrement int 1 CSG
XmNincrementCallback XmCCallback XtCallbackList NULL C
XmNinitialDelay XmCInitialDelay int 250 ms CSG
XmNmaximum XmCMaximum int 100 CSG
XmNminimum XmCMinimum int 0 CSG
XmNorientation XmCOrientation unsigned char XmVERTICAL CSG
XmNpageDecrementCallback XmCCallback XtCallbackList NULL C
XmNpageIncrement XmCPageIncrement int 10 CSG
XmNpageIncrementCallback XmCCallback XtCallbackList NULL C
XmNprocessingDirection XmCProcessingDirection unsigned char dynamic CSG
XmNrepeatDelay XmCRepeatDelay int 50 ms CSG
XmNshowArrows XmCShowArrows XtEnum XmEACH_SIDE CSG
XmNsliderSize XmCSliderSize int dynamic CSG
XmNsliderMark XmCSliderMark XtEnum dynamic CSG
XmNsliderVisual XmCSliderVisual XtEnum XmSHADOWED CSG
XmNslidingMode XmCSlidingMode XtEnum XmSLIDER CSG
XmNsnapBackMultiple XmCSnapBackMultiple unsigned short MaxValue CSG
XmNtoBottomCallback XmCCallback XtCallbackList NULL C
XmNtoTopCallback XmCCallback XtCallbackList NULL C
XmNtroughColor XmCTroughColor Pixel dynamic CSG
XmNvalue XmCValue int dynamic CSG
XmNvalueChangedCallback XmCCallback XtCallbackList NULL C
XmNdecrementCallback
Specifies the list of callbacks that is called when the user
takes an action that moves the ScrollBar by one increment and
the value decreases. The reason passed to the callback is
XmCR_DECREMENT.
XmNdragCallback
Specifies the list of callbacks that is called on each
incremental change of position when the slider is being
dragged. The reason sent by the callback is XmCR_DRAG.
XmNeditable
Specifies how ScrollBar will react to user input. This
resource can be True or False values, as follows:
True Allows the scrollbar to be sensitive to user input.
This is the default value.
False Makes the Scale scrollbar insensitive to user
input. The visual is not greyed out. This value
would mostly be used in XmTHERMOMETER mode.
When XmNeditable is used on a widget it sets the dropsite to
XmDROP_SITE_ACTIVE.
XmNincrement
Specifies the amount by which the value increases or
decreases when the user takes an action that moves the slider
by one increment. The actual change in value is the lesser
of XmNincrement and (previous XmNvalue - XmNminimum) when the
slider moves to the end of the ScrollBar with the minimum
value, and the lesser of XmNincrement and (XmNmaximum-
XmNsliderSize - previous XmNvalue) when the slider moves to
the end of the ScrollBar with the maximum value. The value
of this resource must be greater than 0 (zero).
XmNincrementCallback
Specifies the list of callbacks that is called when the user
takes an action that moves the ScrollBar by one increment and
the value increases. The reason passed to the callback is
XmCR_INCREMENT.
XmNinitialDelay
Specifies the amount of time in milliseconds to wait before
starting continuous slider movement while a button is pressed
in an arrow or the scroll region. The value of this resource
must be greater than 0 (zero).
XmNmaximum
Specifies the slider's maximum value. XmNmaximum must be
greater than XmNminimum.
XmNminimum
Specifies the slider's minimum value. XmNmaximum must be
greater than XmNminimum.
XmNorientation
Specifies whether the ScrollBar is displayed vertically or
horizontally. This resource can have values of XmVERTICAL
and XmHORIZONTAL.
XmNpageDecrementCallback
Specifies the list of callbacks that is called when the user
takes an action that moves the ScrollBar by one page
increment and the value decreases. The reason passed to the
callback is XmCR_PAGE_DECREMENT.
XmNpageIncrement
Specifies the amount by which the value increases or
decreases when the user takes an action that moves the slider
by one page increment. The actual change in value is the
lesser of XmNpageIncrement and (previous XmNvalue -
XmNminimum) when the slider moves to the end of the ScrollBar
with the minimum value, and the lesser of XmNpageIncrement
and (XmNmaximum- XmNsliderSize - previous XmNvalue) when the
slider moves to the end of the ScrollBar with the maximum
value. The value of this resource must be greater than 0
(zero).
XmNpageIncrementCallback
Specifies the list of callbacks that is called when the user
takes an action that moves the ScrollBar by one page
increment and the value increases. The reason passed to the
callback is XmCR_PAGE_INCREMENT.
XmNprocessingDirection
Specifies whether the value for XmNmaximum should be on the
right or left side of XmNminimum for horizontal ScrollBars or
above or below XmNminimum for vertical ScrollBars. This
resource can have values of XmMAX_ON_TOP, XmMAX_ON_BOTTOM,
XmMAX_ON_LEFT, and XmMAX_ON_RIGHT. If the ScrollBar is
oriented vertically, the default value is XmMAX_ON_BOTTOM.
If the ScrollBar is oriented horizontally, the default value
depends on the XmNlayoutDirection resource of the widget.
XmNrepeatDelay
Specifies the amount of time in milliseconds to wait between
subsequent slider movements after the XmNinitialDelay has
been processed. The value of this resource must be greater
than 0 (zero).
XmNshowArrows
Specifies whether the arrows are displayed and how they are
to be displayed. This resource can take the following values:
XmEACH_SIDE
Indicates that one arrow is displayed on each end
of the ScrollBar slider. This corresponds to a
value of True in previous releases.
XmMAX_SIDE
Indicates that both arrows are displayed on the
XmNmaximum side of the ScrollBar slider.
XmMIN_SIDE
Indicates that both arrows are displayed on the
XmNminimum side of the ScrollBar slider.
XmNONE Indicates that no arrows are displayed. This
corresponds to a value of False in previous
releases.
XmEACH_SIDE is the default value.
XmNsliderMark
Specifies the shape the slider is to be displayed in. This
resource can take the following values:
XmETCHED_LINE
Specifies the slider as an etched line.
XmNONE Specifies the slider as a foregrounded rectangle.
This is the default for a regular slider.
XmROUND_MARK
Specifies the slider as a shadowed circle. This is
the default when the slider is a thermometer.
XmTHUMB_MARK
Specifies the slider as a series of three etched
lines centered in the middle of the slider.
XmNslidingMode
Specifies the mode the slider works in. There are two
possible modes:
XmSLIDER Allows the slider to move freely between the
minimum and maximum ends of the scale. This is the
default value.
XmTHERMOMETER
Forces the slider to be anchored to one side of the
trough area.
XmNsliderSize
Specifies the length of the slider between the values of 1
and (XmNmaximum - XmNminimum). The value is constrained to
be within these inclusive bounds. The default value is
(XmNmaximum - XmNminimum) divided by 10, with a minimum of 1.
XmNsliderVisual
Specifies the color of the slider visual. This resource can
take the following values:
XmBACKGROUND_COLOR
Specifies that the slider visual is in the
background color.
XmFOREGROUND_COLOR
Specifies that the slider visual is in the
foreground color.
XmSHADOWED_BACKGROUND
Specifies that the slider visual is in the
background color, with a shadow. This is the
default for a regular slider.
XmTROUGH_COLOR
Specifies that the slider visual is in the trough
color. This is the default when the slider is a
thermometer.
XmNsnapBackMultiple
Specifies the distance over which the scrollbar slider snaps
back to its original position when the user drags the mouse
outside the ScrollBar edge. This distance is defined in terms
of multiples of the width of the slider. For example, a
multiple of 0 (zero) causes the slider to snap back as soon
as the pointer moves out of the ScrollBar frame, a multiple
of 1 causes the slider to snap back as soon as the pointer
moves beyond 1 ScrollBar width of the ScrollBar edge.
Whenever the slider snaps back, the ScrollBar dragCallback is
called if there is one.
The default value is large enough to prevent unwanted
snapBack activity if the mouse is moved within the boundaries
of any reasonable screen. To reset the default, set this
resource to a large value, such as 10000.
XmNtoBottomCallback
Specifies the list of callbacks that is called when the user
takes an action that moves the slider to the end of the
ScrollBar with the maximum value. The reason passed to the
callback is XmCR_TO_BOTTOM.
XmNtoTopCallback
Specifies the list of callbacks that is called when the user
takes an action that moves the slider to the end of the
ScrollBar with the minimum value. The reason passed to the
callback is XmCR_TO_TOP.
XmNtroughColor
Specifies the color of the slider trough. This color
defaults to the color used for selections.
XmNvalue Specifies the slider's position, between XmNminimum and
(XmNmaximum - XmNsliderSize). The value is constrained to be
within these inclusive bounds. The initial value of this
resource is the larger of 0 (zero) and XmNminimum.
XmNvalueChangedCallback
Specifies the list of callbacks that is called when the
slider is released after being dragged. These callbacks are
also called in place of XmNincrementCallback,
XmNdecrementCallback, XmNpageIncrementCallback,
XmNpageDecrementCallback, XmNtoTopCallback, or
XmNtoBottomCallback when one of these callback lists would
normally be called but the value of the corresponding
resource is NULL. The reason passed to the callback is
XmCR_VALUE_CHANGED.
Inherited Resources
ScrollBar inherits behavior and resources from the superclasses
described in the following tables. For a complete description of each
resource, refer to the reference page for that superclass.
XmPrimitiveResource Set
Name Class Type Default Access
XmNbottomShadowColor XmCBottomShadowColor Pixel dynamic CSG
XmNbottomShadowPixmap XmCBottomShadowPixmap Pixmap XmUNSPECIFIED_PIXMAP CSG
XmNconvertCallback XmCCallback XtCallbackList NULL C
XmNforeground XmCForeground Pixel dynamic CSG
XmNhelpCallback XmCCallback XtCallbackList NULL C
XmNhighlightColor XmCHighlightColor Pixel dynamic CSG
XmNhighlightOnEnter XmCHighlightOnEnter Boolean False CSG
XmNhighlightPixmap XmCHighlightPixmap Pixmap dynamic CSG
XmNhighlightThickness XmCHighlightThickness Dimension dynamic CSG
XmNlayoutDirection XmCLayoutDirection XmDirection dynamic CG
XmNnavigationType XmCNavigationType XmNavigationType XmSTICKY_TAB_GROUP CSG
XmNpopupHandlerCallback XmCCallback XtCallbackList NULL C
XmNshadowThickness XmCShadowThickness Dimension 2 CSG
XmNtopShadowColor XmCTopShadowColor Pixel dynamic CSG
XmNtopShadowPixmap XmCTopShadowPixmap Pixmap dynamic CSG
XmNtraversalOn XmCTraversalOn Boolean dynamic CSG
XmNunitType XmCUnitType unsigned char dynamic CSG
XmNuserData XmCUserData XtPointer NULL CSG
Core Resource Set
Name Class Type Default Access
XmNaccelerators XmCAccelerators XtAccelerators dynamic CSG
XmNancestorSensitive XmCSensitive Boolean dynamic G
XmNbackground XmCBackground Pixel dynamic CSG
XmNbackgroundPixmap XmCPixmap Pixmap XmUNSPECIFIED_PIXMAP CSG
XmNborderColor XmCBorderColor Pixel XtDefaultForeground CSG
XmNborderPixmap XmCPixmap Pixmap XmUNSPECIFIED_PIXMAP CSG
XmNborderWidth XmCBorderWidth Dimension 0 CSG
XmNcolormap XmCColormap Colormap dynamic CG
XmNdepth XmCDepth int dynamic CG
XmNdestroyCallback XmCCallback XtCallbackList NULL C
XmNheight XmCHeight Dimension dynamic CSG
XmNinitialResourcesPersistent XmCInitialResourcesPersistent Boolean True C
XmNmappedWhenManaged XmCMappedWhenManaged Boolean True CSG
XmNscreen XmCScreen Screen * dynamic CG
XmNsensitive XmCSensitive Boolean True CSG
XmNtranslations XmCTranslations XtTranslations dynamic CSG
XmNwidth XmCWidth Dimension dynamic CSG
XmNx XmCPosition Position 0 CSG
XmNy XmCPosition Position 0 CSG
Callback Information
A pointer to the following structure is passed to each callback:
typedef struct
{
int reason;
XEvent * event;
int value;
int pixel;
} XmScrollBarCallbackStruct;
reason Indicates why the callback was invoked.
event Points to the XEvent that triggered the callback.
value Contains the new slider location value.
pixel Is used only for XmNtoTopCallback and XmNtoBottomCallback.
For horizontal ScrollBars, it contains the x coordinate of
where the mouse button selection occurred. For vertical
ScrollBars, it contains the y coordinate.
Translations
XmScrollBar includes translations from Primitive. The XmScrollBar
translations are described in the following list.
The following key names are listed in the X standard key event
translation table syntax. This format is the one used by Motif to
specify the widget actions corresponding to a given key. A brief
overview of the format is provided under VirtualBindings(3). For a
complete description of the format, please refer to the X Toolkit
Instrinsics Documentation.
s c m a <Btn1Down>:
Select()
s c m a <Btn1Up>:
Release()
s c m a Button1<PtrMoved>:
Moved()
s c m a <Btn2Down>:
Select()
s c m a <Btn2Up>:
Release()
s c m a Button2<PtrMoved>:
Moved()
s c m a <Btn1Down>:
TopOrBottom()
s c m a <Btn1Up>:
Release()
:<Key><osfActivate>:
PrimitiveParentActivate()
:<Key><osfCancel>:
CancelDrag()
:<Key><osfBeginLine>:
TopOrBottom()
:<Key><osfEndLine>:
TopOrBottom()
:<Key><osfPageLeft>:
PageUpOrLeft(Left)
:c <Key><osfPageUp>:
PageUpOrLeft(Left)
:<Key><osfPageUp>:
PageUpOrLeft(Up)
:<Key><osfPageRight>:
PageDownOrRight(Right)
:c <Key><osfPageDown>:
PageDownOrRight(Right)
:<Key><osfPageDown>:
PageDownOrRight(Down)
:<Key><osfHelp>:
PrimitiveHelp()
:c <Key><osfUp>:
PageUpOrLeft(Up)
:<Key><osfUp>:
IncrementUpOrLeft(Up)
:c <Key><osfDown>:
PageDownOrRight(Down)
:<Key><osfDown>:
IncrementDownOrRight(Down)
:c <Key><osfLeft>:
PageUpOrLeft(Left)
:<Key><osfLeft>:
IncrementUpOrLeft(Left)
:c <Key><osfRight>:
PageDownOrRight(Right)
:<Key><osfRight>:
IncrementDownOrRight(Right)
s m a <Key>Return:
PrimitiveParentActivate()
s m a <Key>Tab:
PrimitivePrevTabGroup()
m a <Key>Tab:
PrimitiveNextTabGroup()
Action Routines
The ScrollBar action routines are
CancelDrag():
If the key press occurs during scrolling, cancels the scroll
and returns the slider to its previous location in the
scrollbar, otherwise, and if the parent is a manager, it
passes the event to the parent.
IncrementDownOrRight(Down|Right):
With an argument of Down, or 0 (zero) for compatibility,
moves the slider down by one increment. With an argument of
Right, or 1 for compatibility, it moves the slider right by
one increment. If XmNprocessingDirection is XmMAX_ON_RIGHT
or XmMAX_ON_BOTTOM, movement toward the right or bottom calls
the callbacks for XmNincrementCallback. If
XmNprocessingDirection is XmMAX_ON_LEFT or XmMAX_ON_TOP,
movement toward the right or bottom calls the callbacks for
XmNdecrementCallback. The XmNvalueChangedCallback is called
if the XmNincrementCallback or XmNdecrementCallback is NULL.
IncrementUpOrLeft(Up|Left):
With an argument of Up, or 0 (zero) for compatibility, moves
the slider up by one increment. With an argument of Left, or
1 for compatibility, it moves the slider left by one
increment. If XmNprocessingDirection is XmMAX_ON_RIGHT or
XmMAX_ON_BOTTOM, movement to the left or top calls the
callbacks for XmNdecrementCallback. If
XmNprocessingDirection is XmMAX_ON_LEFT or XmMAX_ON_TOP,
movement to the left or top calls the callbacks for
XmNincrementCallback. The XmNvalueChangedCallback is called
if the XmNincrementCallback or XmNdecrementCallback is NULL.
Moved(): If the button press occurs within the slider, the subsequent
motion events move the slider to the position of the pointer
and call the callbacks for XmNdragCallback.
PageDownOrRight(Down|Right):
With an argument of Down, or 0 (zero) for compatibility,
moves the slider down by one page increment. With an
argument of Right, or 1 for compatibility, moves the slider
right by one page increment. If XmNprocessingDirection is
XmMAX_ON_RIGHT or XmMAX_ON_BOTTOM, movement toward the right
or bottom calls the callbacks for XmNpageIncrementCallback.
If XmNprocessingDirection is XmMAX_ON_LEFT or XmMAX_ON_TOP,
movement toward the right or bottom calls the
XmNpageDecrementCallback callbacks. The
XmNvalueChangedCallback is called if the
XmNpageIncrementCallback or XmNpageDecrementCallback is NULL.
PageUpOrLeft(Up|Left):
With an argument of Up, or 0 (zero) for compatibility, moves
the slider up by one page increment. With an argument of
Left, or 1 for compatibility, it moves the slider left by one
page increment. If XmNprocessingDirection is XmMAX_ON_RIGHT
or XmMAX_ON_BOTTOM, movement to the left or top calls the
callbacks for XmNpageDecrementCallback. If
XmNprocessingDirection is XmMAX_ON_LEFT or XmMAX_ON_TOP,
movement to the left or top calls the
XmNpageIncrementCallback callbacks. The
XmNvalueChangedCallback is called if the
XmNpageIncrementCallback or XmNpageDecrementCallback is NULL.
PrimitiveHelp():
Calls the callbacks for XmNhelpCallback if any exist. If
there are no help callbacks for this widget, this action
calls the help callbacks for the nearest ancestor that has
them.
PrimitiveNextTabGroup():
Traverses to the first item in the next tab group. If the
current tab group is the last entry in the tab group list, it
wraps to the beginning of the tab group list.
PrimitiveParentActivate():
If the parent is a manager, passes the event to the parent.
PrimitivePrevTabGroup():
Traverses to the first item in the previous tab group. If
the beginning of the tab group list is reached, it wraps to
the end of the tab group list.
Release():
If the button press occurs within the slider and the slider
position is changed, the callbacks for
XmNvalueChangedCallback are called.
Select(): In arrow: Moves the slider by one increment in the direction
of the arrow. If XmNprocessingDirection is XmMAX_ON_RIGHT or
XmMAX_ON_BOTTOM, movement toward the right or bottom calls
the callbacks for XmNincrementCallback, and movement to the
left or top calls the callbacks for XmNdecrementCallback. If
XmNprocessingDirection is XmMAX_ON_LEFT or XmMAX_ON_TOP,
movement toward the right or bottom calls the callbacks for
XmNdecrementCallback, and movement to the left or top calls
the callbacks for XmNincrementCallback. The
XmNvalueChangedCallback is called if the XmNincrementCallback
or XmNdecrementCallback is NULL.
In scroll region between an arrow and the slider: Moves the
slider by one page increment in the direction of the arrow.
If XmNprocessingDirection is XmMAX_ON_RIGHT or
XmMAX_ON_BOTTOM, movement toward the right or bottom calls
the callbacks for XmNpageIncrementCallback, and movement to
the left or top calls the callbacks for
XmNpageDecrementCallback. If XmNprocessingDirection is
XmMAX_ON_LEFT or XmMAX_ON_TOP, movement toward the right or
bottom calls the callbacks for XmNpageDecrementCallback, and
movement to the left or top calls the callbacks for
XmNpageIncrementCallback. The XmNvalueChangedCallback is
called if the XmNpageIncrementCallback or
XmNpageDecrementCallback is NULL.
In slider: Activates the interactive dragging of the slider.
If the button is held down in either the arrows or the scroll
region longer than the XmNinitialDelay resource, the slider
is moved again by the same increment and the same callbacks
are called. After the initial delay has been used, the time
delay changes to the time defined by the resource
XmNrepeatDelay.
TopOrBottom():
<Ctrl><Btn1Down> in an arrow or in the scroll region between
an arrow and the slider moves the slider as far as possible
in the direction of the arrow. If XmNprocessingDirection is
XmMAX_ON_RIGHT or XmMAX_ON_BOTTOM, movement toward the right
or bottom calls the callbacks for XmNtoBottomCallback, and
movement to the left or top calls the callbacks for
XmNtoTopCallback. If XmNprocessingDirection is XmMAX_ON_LEFT
or XmMAX_ON_TOP, movement toward the right or bottom calls
the callbacks for XmNtoTopCallback, and movement to the left
or top calls the callbacks for XmNtoBottomCallback. The
XmNvalueChangedCallback is called if the XmNtoTopCallback or
XmNtoBottomCallback is NULL. Pressing <Key><osfBeginLine> or
<Key><osfBeginData> moves the slider to the minimum value and
invokes the XmNtoTopCallback. Pressing <Key><osfEndLine> or
<Key><osfEndData> moves the slider to the maximum value and
invokes the XmNtoBottomCallback.
Virtual Bindings
The bindings for virtual keys are vendor specific. For information
about bindings for virtual buttons and keys, see VirtualBindings(3).
RELATED
Core(3), XmCreateScrollBar(3), XmPrimitive(3), XmScrollBarGetValues(3), XmScrollBarSetValues(3), XmVaCreateScrollBar(3), and XmVaCreateManagedScrollBar(3). XmScrollBar(3)
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