[ Previous | Next | Contents | Glossary | Home | Search ]
Motif 2.1 Programmer's Reference

XmScreen

The Screen widget class

Format

#include <Xm/Screen.h>

DESCRIPTION

The XmScreen object is used by Motif widgets to store information that is specific to a screen. It also allows the toolkit to store certain information on widget hierarchies that would otherwise be unavailable. Each client has one XmScreen object for each screen that it accesses.

An XmScreen object is automatically created when the application creates the first shell on a screen (usually accomplished by a call to XtAppInitialize or XtAppCreateShell). It is not necessary to create an XmScreen object by any other means. An application can use the function XmGetXmScreen to obtain the widget ID of the XmScreen object for a given screen.

An application cannot supply initial values for XmScreen resources as arguments to a call to any function that creates widgets. The application or user can supply initial values in a resource file. After creating the first shell on the screen, the application can use XmGetXmScreen to obtain the widget ID of the XmScreen object and then call XtSetValues to set the XmScreen resources.

Classes

Screen inherits behavior and resources from Core.

The class pointer is xmScreenClass.

The class name is XmScreen.

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 an .Xdefaults file, remove the XmN or XmC prefix and use the remaining letters. To specify one of the defined values for a resource in an .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).


XmScreen Resource Set
Name Class Type Default Access
XmNbitmapConversionModel XmCBitmapConversionModel XtEnum XmPIXMAP CSG??
XmNcolorAllocationProc XmCColorAllocationProc XtProc NULL CSG??
XmNcolorCalculationProc XmCColorCalculationProc XtProc NULL CSG??
XmNdarkThreshold XmCDarkThreshold int dynamic C
XmNdefaultCopyCursorIcon XmCDefaultCopyCursorIcon Widget NULL CSG
XmNdefaultInvalidCursorIcon XmCDefaultInvalidCursorIcon Widget NULL CSG
XmNdefaultLinkCursorIcon XmCDefaultLinkCursorIcon Widget NULL CSG
XmNdefaultMoveCursorIcon XmCDefaultMoveCursorIcon Widget NULL CSG
XmNdefaultNoneCursorIcon XmCDefaultNoneCursorIcon Widget NULL CSG
XmNdefaultSourceCursorIcon XmCDefaultSourceCursorIcon Widget NULL CSG
XmNdefaultValidCursorIcon XmCDefaultValidCursorIcon Widget NULL CSG
XmNfont XmCFont XFontStruct * NULL CSG
XmNforegroundThreshold XmCForegroundThreshold int dynamic C
XmNhorizontalFontUnit XmCHorizontalFontUnit int dynamic CSG
XmNinsensitiveStippleBitmap XmCinsensitiveStippleBitmap Bitmap "50_foreground" CSG
XmNlightThreshold XmCLightThreshold int dynamic C
XmNmenuCursor XmCCursor Cursor arrow C
XmNmoveOpaque XmCMoveOpaque Boolean False CSG
XmNunpostBehavior XmCUnpostBehavior unsigned char XmUNPOST_AND_REPLAY CSG
XmNuseColorObject XmCUseColorObject Boolean False C
XmNuserData XmCUserData XtPointer NULL CSG
XmNverticalFontUnit XmCVerticalFontUnit int dynamic CSG

XmNbitmapConversionModel
Provides a policy for the conversion of xbm and xpm files to the Pixmap type. This resource takes the following values:

XmMATCH_DEPTH
From a supplied xbm or xpm file, generates a converted pixmap file having the same depth as the widget.

XmDYNAMIC_DEPTH
Converts an input xbm file to a Pixmap of depth 1, or converts an input xpm file to a Pixmap having the same depth as the widget.

XmNcolorAllocationProc
Identifies the procedure to be used for color allocation. Normally, this procedure is an application-defined color allocation procedure. However, if no application-defined color allocation procedure is set, the system uses Motif's predefined color allocation procedure.

XmNcolorCalculationProc
Identifies the procedure to be used for per-widget color calculation. Normally, this procedure is an application-defined color calculation procedure. However, if no application-defined color calculation procedure is set, the system uses Motif's predefined color calculation procedure.

XmNdarkThreshold
An integer between 0 (zero) and 100, inclusive, that specifies a level of perceived brightness for a color. If the perceived brightness of the background color is below this level, Motif treats the background as "dark" when computing default shadow and select colors. If this resource is specified for a particular screen, it applies to widgets created on that screen; otherwise it applies to widgets created on all screens. The default value is implementation specific.

XmNdefaultCopyCursorIcon
Specifies the DragIcon used during a drag operation when the operation is a copy and no other pixmap is specified by the application. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNdefaultInvalidCursorIcon
Specifies the DragIcon used to indicate that the cursor is over an invalid drop site during a drag operation when no other pixmap symbol is specified by the application. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNdefaultLinkCursorIcon
Specifies the DragIcon used during a drag operation when the operation is a link and no other pixmap is specified by the application. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNdefaultMoveCursorIcon
Specifies the DragIcon used during a drag operation when the operation is a move and no other pixmap is specified by the application. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNdefaultNoneCursorIcon
Specifies the DragIcon used to indicate that the cursor is not over a drop site during a drag operation when no other pixmap is specified by the application. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNdefaultSourceCursorIcon
Specifies the depth-1 pixmap used as a cursor when an XmNsourceCursorIcon is not provided by the DragContext, or it is not usable. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNdefaultValidCursorIcon
Specifies the DragIcon used to indicate that the cursor is over a valid drop site during a drag operation when no other pixmap is specified by the application. If this resource is NULL, a system default icon is used. The system default icon is determined by the Display resource XmNenableDragIcon.

XmNfont
Specifies a font for use in computing values for XmNhorizontalFontUnit and XmNverticalFontUnit. When an application is initialized, this resource can be supplied in a resource file or through the standard command line options -fn , -font , and -xrm . Note that this resource is used only for the calculation of the font unit values. To specify a font to be used to display text, use a widget's render table resource (XmNrenderTable).

XmNforegroundThreshold
An integer between 0 (zero) and 100, inclusive, that specifies a level of perceived brightness for a color. If the perceived brightness of the background color is equal to or below this level, Motif treats the background as "dark" when computing the default foreground and highlight colors. If the perceived brightness of the background color is above this level, Motif treats the background as "light" when computing the default foreground and highlight colors. When the background is "dark," the default foreground and highlight is white; when the background is "light," the default foreground and highlight is black. If this resource is specified for a particular screen, it applies to widgets created on that screen; otherwise, it applies to widgets created on all screens. The default value is implementation specific.

XmNhorizontalFontUnit
Specifies the horizontal component of the font units used by XmConvertUnits, and is used to interpret the values of geometry resources when the XmNshellUnitType resource of VendorShell or the XmNunitType resource of Gadget, Manager, or Primitive has the value Xm100TH_FONT_UNITS. If no initial value is supplied for this resource, the default is computed from the font specified in XmNfont. If no initial value is supplied for this resource or for XmNfont, the default is 10.

If a call to XtSetValues specifies a value for XmNhorizontalFontUnit, this resource is set to that value. If a call to XtSetValues specifies a value for XmNfont but not for XmNhorizontalFontUnit, this resource is set to a value computed from the new XmNfont.

A horizontal font unit is derived from a font as follows:

  1. If the font has an AVERAGE_WIDTH property, the horizontal font unit is the AVERAGE_WIDTH property divided by 10.

  2. If the font has no AVERAGE_WIDTH property but has a QUAD_WIDTH property, the horizontal font unit is the QUAD_WIDTH property.

  3. If the font has no AVERAGE_WIDTH or QUAD_WIDTH property, the horizontal font unit is the sum of the font structure's min_bounds.width and max_bounds.width divided by 2.3.

    4. XmNinsensitiveStippleBitmap
    Provides widgets with the bitmap to use when generating the insensitive visual. This bitmap is to be used as the stipple for the rendering of insensitive visuals.

    XmNlightThreshold
    An integer between 0 (zero) and 100, inclusive, that specifies a level of perceived brightness for a color. If the perceived brightness of the background color is above this level, Motif treats the background as "light" when computing default shadow and select colors. If this resource is specified for a particular screen, it applies to widgets created on that screen; otherwise, it applies to widgets created on all screens. The default value is implementation specific.

    XmNmenuCursor
    Sets a variable that controls the cursor used whenever this application posts a menu. This resource can be specified only once at application startup time, either by placing it within a defaults file or by using the -xrm command line argument. For example:



    myProg -xrm "*menuCursor: arrow"

    The menu cursor can also be selected in the program through the function XmSetMenuCursor. The following list shows acceptable cursor names. If the application does not specify a cursor or if an invalid name is supplied, the default cursor (an arrow pointing up and to the right) is used.

    X_cursor
    leftbutton

    arrow
    ll_angle

    based_arrow_down
    lr_angle

    based_arrow_up
    man

    boat
    middlebutton

    bogosity
    mouse

    bottom_left_corner
    pencil

    bottom_right_corner
    pirate

    bottom_side
    plus

    bottom_tee
    question_arrow

    box_spiral
    right_ptr

    center_ptr
    right_side

    circle
    right_tee

    clock
    rightbutton

    coffee_mug
    rtl_logo

    cross
    sailboat

    cross_reverse
    sb_down_arrow

    crosshair
    sb_h_double_arrow

    diamond_cross
    sb_left_arrow

    dot
    sb_right_arrow

    dotbox
    sb_up_arrow

    double_arrow
    sb_v_double_arrow

    draft_large
    shuttle

    draft_small
    sizing

    draped_box
    spider

    exchange
    spraycan

    fleur
    star

    gobbler
    target

    gumby
    tcross

    hand1
    top_left_arrow

    hand2
    top_left_corner

    heart
    top_right_corner

    icon
    top_side

    iron_cross
    left_ptr

    left_side
    top_tee

    left_tee
    trek

    ul_angle
    umbrella

    ur_angle
    watch

    xterm

    XmNmoveOpaque
    Specifies whether an interactive operation that moves a window, such as tearing off and dragging a tear-off menu or moving a window in MWM, displays an outline of the window or a representation of the window itself during the move. If the value is True, the operation displays a representation of the window during the move. If the value is False, the operation displays an outline of the window.

    XmNunpostBehavior
    Specifies the behavior of an active menu posted in traversal mode when a subsequent menu button selection is made outside the posted menu. When the value is XmUNPOST_AND_REPLAY, the resource unposts the menu hierarchy and causes the server to replay the event to the window in which the pointer is located. When the value is XmUNPOST, the resource unposts the hierarchy without replaying the event.

    XmNuseColorObject
    Enables and disables the sharing of colors between widgets, and the dynamic changing of colors. A value of False disables this, and a value of True enables it.

    XmNuserData
    Allows the application to attach any necessary specific data to the widget. This is an internally unused resource.

    XmNverticalFontUnit
    Specifies the vertical component of the font units used by XmConvertUnits and used to interpret the values of geometry resources when the XmNshellUnitType resource of VendorShell or the XmNunitType resource of Gadget, Manager, or Primitive has the value Xm100TH_FONT_UNITS. If no initial value is supplied for this resource, the default is computed from the font specified in XmNfont. If no initial value is supplied for this resource or for XmNfont, the default is 10.

    If a call to XtSetValues specifies a value for XmNverticalFontUnit, this resource is set to that value. If a call to XtSetValues specifies a value for XmNfont but not for XmNverticalFontUnit, this resource is set to a value computed from the new XmNfont.

    A vertical font unit is derived from a font as follows:

    1. If the font has a PIXEL_SIZE property, the vertical font unit is the PIXEL_SIZE property divided by 1.8.

    2. If the font has no PIXEL_SIZE property but has POINT_SIZE and RESOLUTION_Y properties, the vertical font unit is the product of the POINT_SIZE and RESOLUTION_Y properties divided by 1400.

    3. If the font has no PIXEL_SIZE, POINT_SIZE, or RESOLUTION_Y properties, the vertical font unit is the sum of the font structure's max_bounds.ascent and max_bounds.descent divided by 2.2.

      4. Inherited Resources

      All of the superclass resources inherited by XmScreen are designated N/A (not applicable).

      RELATED

      Core (3), XmDisplay (3), XmGetXmScreen (3), and XmSetMenuCursor (3),

      [ Previous | Next | Contents | Glossary | Home | Search ]