XmScale(library call) XmScale(library call)
NAME
XmScale -- The Scale widget class
SYNOPSIS
#include <Xm/Scale.h>
DESCRIPTION
Scale is used by an application to indicate a value from within a range of values, and it allows the user to input or modify a value from
the same range.
A Scale has an elongated rectangular region similar to a ScrollBar. A slider inside this region indicates the current value along the
Scale. The user can also modify the Scale's value by moving the slider within the rectangular region of the Scale. A Scale can also include
a label set located outside the Scale region. These can indicate the relative value at various positions along the scale. The placement
of this label depends on the XmNlayoutDirection resource of the widget.
A Scale can be either input/output or output only. An input/output Scale's value can be set by the application and also modified by the
user with the slider. An output-only Scale is used strictly as an indicator of the current value of something and cannot be modified inter-
actively by the user. The XmScale resource XmNeditable specifies whether the user can interactively modify the Scale's value.
The user can specify resources in a resource file for the automatically created gadget that contains the title of the Scale widget. The
name of the gadget is Title. The placement of the title depends on the XmNlayoutDirection resource of the widget. The direction of the
title is based on the widget's layout direction.
Scale uses the XmQTspecifyRenderTable trait, and holds the XmQTtransfer trait.
Data Transfer Behavior
Scale supports dragging of the representation of the Scale value from the Scale when the value is displayed and when the value of the
XmNenableUnselectableDrag resource of XmDisplay is set to True.
As a source of data, Scale supports the following targets and associated conversions of data to these targets:
COMPOUND_TEXT
The widget transfers a string representation of XmNvalue as type COMPOUND_TEXT.
STRING The widget transfers a string representation of XmNvalue as type STRING.
_MOTIF_CLIPBOARD_TARGETS
The widget transfers, as type ATOM, a list of the targets it supports for the CLIPBOARD selection. These include STRING and COM-
POUND_TEXT.
_MOTIF_EXPORT_TARGETS
The widget transfers, as type ATOM, a list of the targets to be used as the value of the DragContext's XmNexportTargets in a
drag-and-drop transfer. These include STRING and COMPOUND_TEXT.
As a source of data, Scale also supports the following standard Motif targets:
BACKGROUND
The widget transfers XmNbackground as type PIXEL.
CLASS The widget finds the first shell in the widget hierarchy that has a WM_CLASS property and transfers the contents as text in the
current locale.
CLIENT_WINDOW
The widget finds the first shell in the widget hierarchy and transfers its window as type WINDOW.
COLORMAP The widget transfers XmNcolormap as type COLORMAP.
FOREGROUND
The widget transfers XmNforeground as type PIXEL.
NAME The widget finds the first shell in the widget hierarchy that has a WM_NAME property and transfers the contents as text in the
current locale.
TARGETS The widget transfers, as type ATOM, a list of the targets it supports. These include the standard targets in this list. These
also include STRING and COMPOUND_TEXT.
TIMESTAMP The widget transfers the timestamp used to acquire the selection as type INTEGER.
_MOTIF_RENDER_TABLE
The widget transfers XmNrenderTable if it exists, or else the default text render table, as type STRING.
_MOTIF_ENCODING_REGISTRY
The widget transfers its encoding registry as type STRING. The value is a list of NULL separated items in the form of tag encod-
ing pairs. This target symbolizes the transfer target for the Motif Segment Encoding Registry. Widgets and applications can use
this Registry to register text encoding formats for specified render table tags. Applications access this Registry by calling
XmRegisterSegmentEncoding and XmMapSegmentEncoding.
Descendants
Scale automatically creates the descendants shown in the following table. An application can use XtNameToWidget to gain access to the
named descendant. In addition, a user or an application can use the named descendant when specifying resource values.
+-----------------+---------------+----------------+
|Named Descendant | Class | Identity |
+-----------------+---------------+----------------+
+-----------------+---------------+----------------+
+-----------------+---------------+----------------+
|Scrollbar | XmScrollBar | scroll bar |
+-----------------+---------------+----------------+
|Title | XmLabelGadget | title of scale |
+-----------------+---------------+----------------+
+-----------------+---------------+----------------+
Classes
Scale inherits behavior, resources, and traits from Core, Composite, Constraint, and XmManager classes.
The class pointer is xmScaleWidgetClass.
The class name is XmScale.
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 val-
ues 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).
+----------------------------------------------------------------------------------------+
| | XmScale Resource|Set | | |
|Name | Class | Type | Default | Access |
+------------------------+------------------------+----------------+------------+--------+
|XmNconvertCallback | XmCCallback | XtCallbackList | NULL | C |
+------------------------+------------------------+----------------+------------+--------+
|XmNdecimalPoints | XmCDecimalPoints | short | 0 | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNdragCallback | XmCCallback | XtCallbackList | NULL | C |
+------------------------+------------------------+----------------+------------+--------+
|XmNeditable | XmCEditable | Boolean | True | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNfontList | XmCFontList | XmFontList | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNhighlightOnEnter | XmCHighlightOnEnter | Boolean | False | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNhighlightThickness | XmCHighlightThickness | Dimension | 2 | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNmaximum | XmCMaximum | int | 100 | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNminimum | XmCMinimum | int | 0 | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNorientation | XmCOrientation | unsigned char | XmVERTICAL | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNprocessingDirection | XmCProcessingDirection | unsigned char | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNscaleHeight | XmCScaleHeight | Dimension | 0 | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNscaleMultiple | XmCScaleMultiple | int | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNscaleWidth | XmCScaleWidth | Dimension | 0 | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNrenderTable | XmCRenderTable | XmRenderTable | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNshowArrows | XmCShowArrows | XtEnum | XmNONE | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNshowValue | XmCShowValue | XtEnum | XmNONE | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNsliderMark | XmCSliderMark | XtEnum | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNsliderVisual | XmCSliderVisual | XtEnum | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNslidingMode | XmCSlidingMode | XtEnum | XmSLIDER | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNtitleString | XmCTitleString | XmString | NULL | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNvalue | XmCValue | int | dynamic | CSG |
+------------------------+------------------------+----------------+------------+--------+
|XmNvalueChangedCallback | XmCCallback | XtCallbackList | NULL | C |
+------------------------+------------------------+----------------+------------+--------+
+------------------------+------------------------+----------------+------------+--------+
XmNconvertCallback
Specifies a list of callbacks called when the Scale is asked to convert a selection. The type of the structure whose address is
passed to these callbacks is XmConvertCallbackStruct. The reason is XmCR_OK.
XmNdecimalPoints
Specifies the number of decimal points to shift the slider value when displaying it. For example, a slider value of 2,350 and an
XmdecimalPoints value of 2 results in a display value of 23.50. The value must not be negative.
XmNdragCallback
Specifies the list of callbacks that is called when the slider position changes as the slider is being dragged. The reason sent
by the callback is XmCR_DRAG.
XmNeditable
Specifies how the Scale 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.
XmNfontList
Specifies the font list to use for the title text string specified by XmNtitleString, and the label displayed when XmNshowValue
is True. The font list is an obsolete structure, and is retained only for compatibility with earlier releases of Motif. See the
XmNrenderTable resource.
XmNhighlightOnEnter
Specifies whether the highlighting rectangle is drawn when the cursor moves into the widget. If the shell's focus policy is
XmEXPLICIT, this resource is ignored, and the widget is highlighted when it has the focus. If the shell's focus policy is
XmPOINTER and if this resource is True, the highlighting rectangle is drawn when the the cursor moves into the widget. If the
shell's focus policy is XmPOINTER and if this resource is False, the highlighting rectangle is not drawn when the the cursor
moves into the widget. The default is False.
XmNhighlightThickness
Specifies the size of the slider's border drawing rectangle used for enter window and traversal highlight drawing.
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
Displays Scale vertically or horizontally. This resource can have values of XmVERTICAL and XmHORIZONTAL.
XmNprocessingDirection
Specifies whether the value for XmNmaximum is on the right or left side of XmNminimum for horizontal Scales or above or below
XmNminimum for vertical Scales. This resource can have values of XmMAX_ON_TOP, XmMAX_ON_BOTTOM, XmMAX_ON_LEFT, and
XmMAX_ON_RIGHT. If the Scale is oriented vertically, the default value is XmMAX_ON_TOP. If the XmScale is oriented horizon-
tally, the default value depends on the XmNlayoutDirection resource of the widget.
XmNrenderTable
Specifies the render table to use for the title text string specified by XmNtitleString, and the label displayed when XmNshow-
Value is True. If this value is NULL at initialization, the parent hierarchy is searched for an ancestor that holds the XmQTspec-
ifyRenderTable trait. If such an ancestor is found, the render table is initialized to the XmLABEL_RENDER_TABLE value of the
ancestor widget. If no such ancestor is found, the default is implementation dependent. If a font list (XmNfontList) and a render
table are both specified, the render table will take precedence. Refer to XmRenderTable(3) for more information on the creation
and structure of a render table.
XmNscaleHeight
Specifies the height of the slider area. The value should be in the specified unit type (the default is pixels). If no value is
specified a default height is computed.
XmNscaleMultiple
Specifies the amount to move the slider when the user takes an action that moves the slider by a multiple increment. The default
is (XmNmaximum - XmNminimum) divided by 10, with a minimum of 1.
XmNscaleWidth
Specifies the width of the slider area. The value should be in the specified unit type (the default is pixels). If no value is
specified a default width is computed.
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.
XmMAX_SIDE
Indicates that one arrow is displayed on the XmNmaximum side of the ScrollBar slider.
XmMIN_SIDE
Indicates that one arrow is displayed on the XmNminimum side of the ScrollBar slider.
XmNONE Indicates that no arrows are displayed.
XmNONE is the default value.
XmNshowValue
Specifies whether a label for the current slider value should be displayed next to the slider. If the value is XmNEAR_SLIDER, the
current slider value is displayed. If the value is XmNONE, no slider value is displayed. If the value is XmNEAR_BORDER, the cur-
rent slider value is displayed near the border.
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. This is the default when XmNslidingMode is XmSLIDER.
XmNONE Specifies the slider as a foregrounded rectangle. This is the default when XmNslidingMode is XmTHERMOMETER and the
Scale scrollbar is insensitive to user input (XmNeditable is False.
XmROUND_MARK
Specifies the slider as a shadowed circle. This is the default when XmNslidingMode is XmTHERMOMETER and the Scale
scrollbar is sensitive to user input (XmNeditable is True.
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.
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 when the XmNsliding-
Model resource is XmSLIDER.
XmTROUGH_COLOR
Specifies that the slider visual is in the trough color. This is the default when the XmNslidingModel resource is
XmTHERMOMETER.
XmNtitleString
Specifies the title text string to appear in the Scale widget window.
XmNvalue Specifies the slider's current position along the scale, between XmNminimum and XmNmaximum. 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 value of the slider has changed. The reason sent by the callback is
XmCR_VALUE_CHANGED.
Inherited Resources
Scale 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.
+----------------------------------------------------------------------------------------------------+
| | XmManager Resource Set | | |
|Name | Class | Type | Default | Access |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNbottomShadowColor | XmCBottomShadowColor | Pixel | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNbottomShadowPixmap | XmCBottomShadowPixmap | Pixmap | XmUNSPECIFIED_PIXMAP | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNforeground | XmCForeground | Pixel | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNhelpCallback | XmCCallback | XtCallbackList | NULL | C |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNhighlightColor | XmCHighlightColor | Pixel | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNhighlightPixmap | XmCHighlightPixmap | Pixmap | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNinitialFocus | XmCInitialFocus | Widget | NULL | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNlayoutDirection | XmCLayoutDirection | XmDirection | dynamic | CG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNnavigationType | XmCNavigationType | XmNavigationType | XmTAB_GROUP | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNpopupHandlerCallback | XmCCallback | XtCallbackList | NULL | C |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNshadowThickness | XmCShadowThickness | Dimension | 2 | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNstringDirection | XmCStringDirection | XmStringDirection | dynamic | CG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNtopShadowColor | XmCTopShadowColor | Pixel | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNtopShadowPixmap | XmCTopShadowPixmap | Pixmap | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNtraversalOn | XmCTraversalOn | Boolean | True | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNunitType | XmCUnitType | unsigned char | dynamic | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
|XmNuserData | XmCUserData | XtPointer | NULL | CSG |
+------------------------+-----------------------+-------------------+----------------------+--------+
+------------------------+-----------------------+-------------------+----------------------+--------+
+-----------------------------------------------------------------------+
| | Composite Resource Set | | |
|Name | Class | Type | Default | Access |
+------------------+-------------------+-------------+---------+--------+
|XmNchildren | XmCReadOnly | WidgetList | NULL | G |
+------------------+-------------------+-------------+---------+--------+
|XmNinsertPosition | XmCInsertPosition | XtOrderProc | NULL | CSG |
+------------------+-------------------+-------------+---------+--------+
|XmNnumChildren | XmCReadOnly | Cardinal | 0 | G |
+------------------+-------------------+-------------+---------+--------+
+------------------+-------------------+-------------+---------+--------+
+---------------------------------------------------------------------------------------------------------------+
| | 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 the XmNdragCallback and XmNvalueChangedCallback procedures:
typedef struct
{
int reason;
XEvent * event;
int value;
} XmScaleCallbackStruct;
reason Indicates why the callback was invoked
event Points to the XEvent that triggered the callback
value Is the new slider value
A pointer to the following structure is passed to the XmNconvertCallback procedures:
typedef struct
{
int reason;
XEvent *event;
Atom selection;
Atom target;
XtPointer source_data;
XtPointer location_data;
int flags;
XtPointer parm;
int parm_format;
unsigned long parm_length;
int status;
XtPointer value;
Atom type;
int format;
unsigned long length;
} XmConvertCallbackStruct;
reason Indicates why the callback was invoked.
event Points to the XEvent that triggered the callback. It can be NULL.
selection Indicates the selection for which conversion is being requested. Possible values are CLIPBOARD, PRIMARY, SECONDARY, and
_MOTIF_DROP.
target Indicates the conversion target.
source_data
Contains information about the selection source. When the selection is _MOTIF_DROP, source_data is the DragContext. Otherwise,
it is NULL.
location_data
Contains information about the location of data to be converted. If the value is NULL, the data to be transferred consists of
the widget's current selection.
flags Indicates the status of the conversion. Following are the possible values:
XmCONVERTING_NONE
This flag is currently unused.
XmCONVERTING_PARTIAL
The target widget was able to be converted, but some data was lost.
XmCONVERTING_SAME
The conversion target is the source of the data to be transferred.
XmCONVERTING_TRANSACT
This flag is currently unused.
parm Contains parameter data for this target. If no parameter data exists, the value is NULL.
When selection is CLIPBOARD and target is _MOTIF_CLIPBOARD_TARGETS or _MOTIF_DEFERRED_CLIPBOARD_TARGETS, the value is the
requested operation (XmCOPY, XmMOVE, or XmLINK).
parm_format
Specifies whether the data in parm should be viewed as a list of char, short, or long quantities. Possible values are 0 (when
parm is NULL), 8 (when the data in parm should be viewed as a list of chars), 16 (when the data in parm should be viewed as a
list of shorts), or 32 (when the data in parm should be viewed as a list of longs). Note that parm_format symbolizes a data
type, not the number of bits in each list element. For example, on some machines, a parm_format of 32 means that the data in
parm should be viewed as a list of 64-bit quantities, not 32-bit quantities.
parm_length
Specifies the number of elements of data in parm, where each element has the size specified by parm_format. When parm is NULL,
the value is 0.
status An IN/OUT member that specifies the status of the conversion. The initial value is XmCONVERT_DEFAULT. The callback procedure
can set this member to one of the following values:
XmCONVERT_DEFAULT
This value means that the widget class conversion procedure, if any, is called after the callback procedures return.
If the widget class conversion procedure produces any data, it overwrites the data provided by the callback procedures
in the value member.
XmCONVERT_MERGE
This value means that the widget class conversion procedure, if any, is called after the callback procedures return.
If the widget class conversion procedure produces any data, it appends its data to the data provided by the callback
procedures in the value member. This value is intended for use with targets that result in lists of data, such as TAR-
GETS.
XmCONVERT_DONE
This value means that the callback procedure has successfully finished the conversion. The widget class conversion
procedure, if any, is not called after the callback procedures return.
XmCONVERT_REFUSE
This value means that the callback procedure has terminated the conversion process without completing the requested
conversion. The widget class conversion procedure, if any, is not called after the callback procedures return.
value An IN/OUT parameter that contains any data that the callback procedure produces as a result of the conversion. The initial value
is NULL. If the callback procedure sets this member, it must ensure that the type, format, and length members correspond to the
data in value. The callback procedure is responsible for allocating, but not for freeing, memory when it sets this member.
type An IN/OUT parameter that indicates the type of the data in the value member. The initial value is INTEGER.
format An IN/OUT parameter that specifies whether the data in value should be viewed as a list of char, short, or long quantities. The
initial value is 8. The callback procedure can set this member to 8 (for a list of char), 16 (for a list of short), or 32 (for a
list of long).
length An IN/OUT member that specifies the number of elements of data in value, where each element has the size symbolized by format.
The initial value is 0.
Behavior
XmScale has the following behavior:
<Btn1Down> or <Btn2Down>:
In the region between an end of the Scale and the slider: Moves the slider by one multiple increment in the direction of the end
of the Scale and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirection is XmMAX_ON_RIGHT or XmMAX_ON_BOTTOM,
movement toward the right or bottom increments the Scale value, and movement toward the left or top decrements the Scale value.
If XmNprocessingDirection is XmMAX_ON_LEFT or XmMAX_ON_TOP, movement toward the right or bottom decrements the Scale value, and
movement toward the left or top increments the Scale value. If the button is held down longer than a delay period, the slider is
moved again by the same increment and the same callbacks are called.
In slider: Activates the interactive dragging of the slider.
<Btn2Down> in value label:
Drags the contents of the label showing the current slider value. This action sets the XmNconvertProc of the DragContext to a
function that calls the XmNconvertCallback procedures, possibly multiple times, for the _MOTIF_DROP selection.
<Btn1Motion> or <Btn2Motion>:
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.
<Btn1Up> or <Btn2Up>:
If the button press occurs within the slider and the slider position is changed, the callbacks for XmNvalueChangedCallback are
called.
<Ctrl><Btn1Down>:
In the region between an end of the Scale and the slider: Moves the slider to that end of the Scale and calls the XmNval-
ueChangedCallback callbacks. If XmNprocessingDirection is XmMAX_ON_RIGHT or XmMAX_ON_BOTTOM, movement toward the right or bottom
increments the Scale value, and movement toward the left or top decrements the Scale value. If XmNprocessingDirection is
XmMAX_ON_LEFT or XmMAX_ON_TOP, movement toward the right or bottom decrements the Scale value, and movement toward the left or
top increments the Scale value.
<Key><osfUp>:
For vertical Scales, moves the slider up one increment and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirec-
tion is XmMAX_ON_TOP, movement toward the top increments the Scale value. If XmNprocessingDirection is XmMAX_ON_BOTTOM, movement
toward the top decrements the Scale value.
<Key><osfDown>:
For vertical Scales, moves the slider down one increment and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirec-
tion is XmMAX_ON_BOTTOM, movement toward the bottom increments the Scale value. If XmNprocessingDirection is XmMAX_ON_TOP, move-
ment toward the bottom decrements the Scale value.
<Key><osfLeft>:
For horizontal Scales, moves the slider one increment to the left and calls the XmNvalueChangedCallback callbacks. If XmNpro-
cessingDirection is XmMAX_ON_LEFT, movement toward the left increments the Scale value. If XmNprocessingDirection is
XmMAX_ON_RIGHT, movement toward the left decrements the Scale value.
<Key><osfRight>:
For horizontal Scales, moves the slider one increment to the right and calls the XmNvalueChangedCallback callbacks. If XmNpro-
cessingDirection is XmMAX_ON_RIGHT, movement toward the right increments the Scale value. If XmNprocessingDirection is
XmMAX_ON_LEFT, movement toward the right decrements the Scale value.
<Ctrl><Key><osfUp> or <Key><osfPageUp>:
For vertical Scales, moves the slider up one multiple increment and calls the XmNvalueChangedCallback callbacks. If XmNprocess-
ingDirection is XmMAX_ON_TOP, movement toward the top increments the Scale value. If XmNprocessingDirection is XmMAX_ON_BOTTOM,
movement toward the top decrements the Scale value.
<Ctrl><Key><osfDown> or <Key><osfPageDown>:
For vertical Scales, moves the slider down one multiple increment and calls the XmNvalueChangedCallback callbacks. If XmNpro-
cessingDirection is XmMAX_ON_BOTTOM, movement toward the bottom increments the Scale value. If XmNprocessingDirection is
XmMAX_ON_TOP, movement toward the bottom decrements the Scale value.
<Ctrl><Key><osfLeft> or <Key><osfPageLeft>:
For horizontal Scales, moves the slider one multiple increment to the left and calls the XmNvalueChangedCallback callbacks. If
XmNprocessingDirection is XmMAX_ON_LEFT, movement toward the left increments the Scale value. If XmNprocessingDirection is
XmMAX_ON_RIGHT, movement toward the left decrements the Scale value.
<Ctrl><Key><osfRight> or <Key><osfPageRight>:
For horizontal Scales, moves the slider one multiple increment to the right and calls the XmNvalueChangedCallback callbacks. If
XmNprocessingDirection is XmMAX_ON_RIGHT, movement toward the right increments the Scale value. If XmNprocessingDirection is
XmMAX_ON_LEFT, movement toward the right decrements the Scale value.
<Key><osfBeginLine> or <Key><osfBeginData>:
Moves the slider to the minimum value and calls the XmNvalueChangedCallback callbacks.
<Key><osfEndLine> or <Key><osfEndData>:
Moves the slider to the maximum value and calls the XmNvalueChangedCallback callbacks.
<Key><osfNextField>:
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.
<Key><osfPrevField>:
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.
<Key><osfHelp>:
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.
Virtual Bindings
The bindings for virtual keys are vendor specific. For information about bindings for virtual buttons and keys, see VirtualBindings(3).
RELATED
Composite(3), Constraint(3), Core(3), XmCreateScale(3), XmManager(3), XmScaleGetValue(3), and XmScaleSetValue(3).
XmScale(library call)