XmScale(Xm)

XmScale -- the Scale widget class

Syntax

#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.

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 interactively by the user. The Core resource XmNsensitive 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''.

Classes

Scale inherits behavior and resources 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 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).

XmScale resource set

Name Class Type Default Access

XmNdecimalPoints XmCDecimalPoints short 0 CSG

XmNdragCallback XmCCallback XtCallbackList NULL C

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

XmNshowValue XmCShowValue Boolean False CSG

XmNtitleString XmCTitleString XmString NULL CSG

XmNvalue XmCValue int dynamic CSG

XmNvalueChangedCallback XmCCallback XtCallbackList NULL C

Name	Class	Type	Default	Access
XmNdecimalPoints	XmCDecimalPoints	short	0	CSG
XmNdragCallback	XmCCallback	XtCallbackList	NULL	C
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
XmNshowValue	XmCShowValue	Boolean	False	CSG
XmNtitleString	XmCTitleString	XmString	NULL	CSG
XmNvalue	XmCValue	int	dynamic	CSG
XmNvalueChangedCallback	XmCCallback	XtCallbackList	NULL	C

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.
XmNfontList: Specifies the font list to use for the title text string specified by XmNtitleString, and the label displayed when XmNshowValue is True. If this value is NULL at initialization, the font list is initialized by looking up the parent hierarchy of the widget for an ancestor that is a subclass of the XmBulletinBoard, VendorShell, or XmMenuShell widget class. If such an ancestor is found, the font list is initialized to the XmNlabelFontList of the ancestor widget. If no such ancestor is found, the default is implementation dependent. Refer to XmFontList(Xm) for more information on the creation and structure of a font list.
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 XmScale is oriented vertically, the default value is XmMAX_ON_TOP. If the XmScale is oriented horizontally, the default value may depend on the value of the XmNstringDirection resource.
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.
XmNshowValue: Specifies whether a label for the current slider value should be displayed next to the slider. If the value is True, the current slider value is displayed.
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 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 following superclasses. For a complete description of each resource, refer to the man 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

XmNnavigationType XmCNavigationType XmNavigationType XmTAB_GROUP CSG

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

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
XmNnavigationType	XmCNavigationType	XmNavigationType	XmTAB_GROUP	CSG
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

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

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;
   } XmScaleCallbackStruct;

reason: Indicates why the callback was invoked
event: Points to the XEvent that triggered the callback
value: Is the new slider value

Behavior

XmScale behavior is described below:

BSelect Press or BDrag Press:: (in 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.
BSelect Motion or BDrag Motion:: 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.
BSelect Release or BDrag Release:: If the button press occurs within the slider and the slider position is changed, the callbacks for XmNvalueChangedCallback are called.
MCtrl BSelect Press:: (in region between an end of the Scale and the slider): Moves the slider to that 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.
KUp:: For vertical Scales, moves the slider up one increment and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirection 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.
KDown:: For vertical Scales, moves the slider down one increment and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirection 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.
KLeft:: For horizontal Scales, moves the slider one 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.
KRight:: For horizontal Scales, moves the slider one 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.
MCtrl KUp or KPageUp:: For vertical Scales, moves the slider up one multiple increment and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirection 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.
MCtrl KDown or KPageDown:: For vertical Scales, moves the slider down one multiple increment and calls the XmNvalueChangedCallback callbacks. If XmNprocessingDirection 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.
MCtrl KLeft or KPageLeft:: 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.
MCtrl KRight or KPageRight:: 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.
KBeginLine or KBeginData:: Moves the slider to the minimum value and calls the XmNvalueChangedCallback callbacks.
KEndLine or KEndData:: Moves the slider to the maximum value and calls the XmNvalueChangedCallback callbacks.
KNextField:: 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.
KPrevField:: 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.
KHelp:: 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(Xm).