.DT

.TH "XmDropDown" "library call"

.SH NAME

\fBXmDropDown\fP \(em The DropDown widget class

.SH "SYNOPSIS"

.PP

.nf

#include <Xm/DropDown\&.h>

.fi

.SH DESCRIPTION

.PP

The DropDown widget allows the user to select elements from a list of choices, 

and enter their own values in a text widget. To conserve screen space, the list of choices 

is shown only when the user selects the down arrow button. The choices may then be 

selected from this list. If the list widget is in Browse Select mode (the default) or Single 

Select mode, then the list will automatically be removed when the user selects an item 

in the list. When the list is in other modes, multiple items may be selected and the list 

may be popped down by either another click on the arrow button, a click outside the 

list or double-clicking an item. When using keyboard traversal, the list may be popped 

down by selecting the arrow button or Alt - down arrow, and popped back up by typing either 

the osfActivate key, a carriage return, or Alt - up arrow. In any case, when 

the list is removed the item or items that were selected will be placed in the text widget 

separated by commas. Typing the escape key when the list is up, cancels the list popup, 

restoring the DropDown widget to the state it was in before the list was popped up. If

the text field area is non-editable, clicking anywhere in the text field the list will

also pop down.

.PP

Resources are available to change the margin sizes, the location of the left edge of the 

popup list, whether or not the label is shown, whether the text field widget may be 

edited, and whether or not the text in the list is verified against the choices available in 

the list. By setting resources that occur in the children of the DropDown widget, the 

contents of the list, the number of items visible in the list, the initial value of the text 

field, and the value of the label may be set or changed dynamically.

.PP

If a developer wishes the popup list's shell to be resizable, they should set the

allowShellResize to True at creation time.

.SS "Classes"

.PP

\fBXmDropDown\fP inherits behavior, resources, and traits from \fBCore\fP,

\fBComposite\fP, and \fBXmManager\fP classes\&.

.PP

The class pointer is \fBxmDropDownWidgetClass\fP\&.

.PP

The class name is \fBXmDropDown\fP\&.

.PP

.SS "New Resources"

.PP

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 \fB\&.Xdefaults\fP file, remove the \fBXmN\fP or \fBXmC\fP prefix and

use the

remaining letters\&. To specify one of the defined values for a

resource in a \fB\&.Xdefaults\fP file, remove the \fBXm\fP 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 at

creation time (C), set by using \fBXtSetValues\fP (S), retrieved by

using \fBXtGetValues\fP (G), or is not applicable (N/A)\&.

.TS

tab(?) box;

c s s s s

l| l| l| l| l.

\fBXmDropDown Resource Set\fP

\fBName\fP?\fBClass\fP?\fBType\fP?\fBDefault\fP?\fBAccess\fP

_?_?_?_?_?

XmNcustomizedCombinationBox?XmCBoolean?Boolean?False?CSG

_?_?_?_?_?

XmNeditable?XmCBoolean?Boolean?True?CSG

_?_?_?_?_?

XmNhorizontalMargin?XmCMargin?Dimension?2?CSG

_?_?_?_?_?

XmNitemCount?list?int?0?CSG

_?_?_?_?_?

XmNitems?list?XmStringTable?NULL?CSG

_?_?_?_?_?

XmNlabelString?label?XmString?"label"?CSG

_?_?_?_?_?

XmNpopupCursor?XmCCursor?Cursor?left_ptr?CSG

_?_?_?_?_?

XmNpopupOffset?MxCPopupOffset?int?15?CSG

_?_?_?_?_?

XmNpopupShellWidget?XmCWidget?Widget?NULL?CSG

_?_?_?_?_?

XmNshowLabel?XmCBoolean?Boolean?True?CSG

_?_?_?_?_?

XmNupdateShellCallback?XmCCallback?XtCallbackList?NULL?CSG

_?_?_?_?_?

XmNupdateTextCallback?XmCCallback?XtCallbackList?NULL?CSG

_?_?_?_?_?

XmNuseTextField?XmCUseTextField?Boolean?True?CSG

_?_?_?_?_?

XmNvalue?text?String?""?CSG

_?_?_?_?_?

XmNverify?XmCVerify?Boolean?True?CSG

_?_?_?_?_?

XmNverifyTextCallback?XmCCallback?XtCallbackList?NULL?CSG

_?_?_?_?_?

XmNverticalMargin?XmCMargin?Dimension?2?CSG

_?_?_?_?_?

XmNvisibleItemCount?XmCVisibleItemCount?int?0?CSG

_?_?_?_?_?

.TE

.IP "\fBXmNcustomizedCombinationBox\fP" 10

If this resource is True then the widget will not automatically create a popup shell 

and list widget. This resource can be used, as the name implies, to create a custom 

combination box that has something other than a list in it. If this resource is true 

then a shell must be provided to the DropDown widget via the popupShellWidget 

resource. Just before the shell is popped up the updateShellCallback is called. Just 

after the shell is popped down the updateTextCallback is called. If verify is true 

then the verifyTextCallback is called when the combo box needs to verify the 

contents of the text widget against the allowable values in the custom shell. 

.IP "\fBXmNeditable\fP" 10

This boolean value determines whether the user is allowed to type into 

TextField widget of the DropDown widget. If this value is False, selecting the text

field will popup the combo box list

.IP "\fBXmNhorizontalMargin\fP" 10

Specifies the horizontal spacing between the child widgets and the boundary

of the DropDown widget\&.

.IP "\fBXmNverticalMargin\fP" 10

Specifies the vertical spacing between the child widgets and the boundary

of the DropDown widget\&.

.IP "\fBXmNitemCount\fP" 10

The number of items in the popup list.

.IP "\fBXmNitems\fP" 10

The list of all choice that will be displayed in the popup list.

.IP "\fBXmNlabelString\fP" 10

The string displayed as the label of the DropDown widget.

.IP "\fBXmNpopupCursor\fP" 10

The cursor to display to the user when the DropDown's list is popped up. 

See X Window System, Robert Scheiffler et al., Appendix B, for choices.

.IP "\fBXmNpopupOffset\fP" 10

The amount of space in pixels between the left edge of the Text widget and the left 

edge of the list when the list is displayed. Positive values mean the text's left edge 

is farther to the left, negative values mean the list's edge is farther to the left. If this 

is a non-custom DropDown widget the right edge of the text and the right edge of 

the arrow button will always line up.

.IP "\fBXmNpopupShellWidget\fP" 10

The widget identifier for the shell that is popped up when the arrow is clicked. If 

customizedCombinationBox is False then this widget is automatically created 

by the DropDown widget.

.IP "\fBXmNshowLabel\fP" 10

A boolean value that specifies whether or not to display the DropDown 

Label widget.

.IP "\fBXmNupdateShellCallback\fP" 10

.IP "\fBXmNupdateTextCallback\fP" 10

The callback routine to call when either the shell widget contents or the Text 

widget need to be updated to correspond with the other. The shell is updated just 

before it is popped up. The text is updated just after the shell is popped down. If 

customizedComboBox is False then the updates are done automatically by the 

combo box. These routines are called to inform the application that an action has 

been taken, in case it would like to do any further processing.

.IP "\fBXmNuseTextField\fP" 10

A boolean value that specifies if an XmTextField or an XmText widget

should be used for the text entry portion of the DropDown widget.

.IP "\fBXmNvalue\fP" 10

The string displayed in the Text widget.

.IP "\fBXmNverify\fP" 10

If this resource is true the DropDown widget will verify its value against the list 

whenever it loses focus or the user types <Carriage Return>. If the verification 

fails, an XtWarning is generated with a name of XmNtextVerifyFailed. To trap this 

message register an XtWarningMsgHandler.

.IP "\fBXmNverifyTextCallback\fP" 10

This routine is called whenever the Text widget's contents may need to be verified 

against the popup shell's contents. If the customizedComboBox resource is False 

then the DropDown widget has already performed the verification when this 

routine is called.

.IP "\fBXmNvisibleItemCount\fP" 10

The number of items visible in the popup list at one time.

.RE

.SS Children

.PP

The DropDown is composed of many sub-widgets. Most of the information 

displayed to the user is set through these sub widgets. Most 

values passed to this widget through the argument list at creation time or via set values 

are passed to each of this widget's children. Get values requests must be made on a 

child by child basis. The children of the DropDown are listed below. The 

OSF/Motifdocumentation should be consulted for an exhaustive set of resources for each child.

A partial list of the most common resources are listed here for convenience.

.PP

.ta 18n 35n 40n 50n

.df

XmDropDown	comboBox

	XmLabel	label

	XmTextField	text

	XmArrowButton	arrow

	OverrideShell	popupShell

	XmScrolledWindow	listSW

		XmScrollBar	ListvScrollBar

		XmScrollBar	ListhScrollBar

		XmList	list

.fi

The popup shell and its children are only created when 

customizedCombinationBox is False.

.PP

.SS "Inherited Resources"

.PP

XmDropDown 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\&.

.PP

.TS

tab(?) box;

c s s s s

l| l| l| l| l.

\fBXmManager Resource Set\fP

\fBName\fP?\fBClass\fP?\fBType\fP?\fBDefault\fP?\fBAccess\fP

_?_?_?_?_?

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?0?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

_?_?_?_?_?

.TE

.PP

.TS

tab(?) box;

c s s s s

l| l| l| l| l.

\fBComposite Resource Set\fP

\fBName\fP?\fBClass\fP?\fBType\fP?\fBDefault\fP?\fBAccess\fP

_?_?_?_?_?

XmNchildren?XmCReadOnly?WidgetList?NULL?G

_?_?_?_?_?

XmNinsertPosition?XmCInsertPosition?XtOrderProc?NULL?CSG

_?_?_?_?_?

XmNnumChildren?XmCReadOnly?Cardinal?0?G

_?_?_?_?_?

.TE

.TS

tab(?) box;

c s s s s

l| l| l| l| l.

\fBCore Resource Set\fP

\fBName\fP?\fBClass\fP?\fBType\fP?\fBDefault\fP?\fBAccess\fP

_?_?_?_?_?

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

_?_?_?_?_?

.TE

.SS "Callback Information"

.PP

None of the DropDown's callback procedures have any call data currently 

defined for them. The widget passed to each of these functions is the DropDown

widget.

.HP 20

void (Callback)(Widget cbw, XtPointer client_data, XtPointer unused)

.ta 15

.HP 15

cbw		This is the widget identifier of the DropDown widget.

.PP

.HP 15

client_data		The client data passed to this widget by the application programmer.

.HP 15

unused		This value is undefined.

.PP

.SS "Geometry Management"

.PP

The DropDown widget lays out its children (the label, text and arrow) in a row. 

The amount of space they are each allocated when the DropDown is not allowed 

to be the exact size it desires is determined using the following rules:

.ta 5

.HP 5

1.	The arrow is always given its requested size.

.HP 5

2.	If the combo box is bigger than it wants to be all extra space is given to the text 

widget.

.HP 5

3.	If the combo box is smaller that is wants to be then the text and label widgets 

are each sized smaller than they desire in exactly the same ratio.

For example:

If the amount of space for the label and text is 100 pixels and the label 

wants to be 50 pixels wide and the text would like to be 100 pixels wide 

then the label will get 34 pixels and the text 66.

The popup shell widget is sized such that the width of the scrolled list widget equals 

the width of the text widget minus the value of the "popupOffset" resource. If the 

popup shell resides in a customized combination box, however, it is allowed to be 

whatever size the child of the popup shell would like to be.

.PP

.SH RELATED

.PP

\fBComposite\fP(3),

\fBCore\fP(3),

\fBXmCreateDropDown\fP(3),

\fBXmDropDownGetArrow\fP(3),

\fBXmDropDownGetLabel\fP(3),

\fBXmDropDownGetList\fP(3),

\fBXmDropDownGetText\fP(3),

\fBXmDropDownGetValue\fP(3),

\fBXmList\fP(3),

\fBXmManager\fP(3),

\fBXmTextField\fP(3),

\fBXmVaCreateDropDown\fP(3), and

\fBXmVaCreateManagedDropDown\fP(3)\&.

.PP

.SH COPYRIGHT

.PP

Copyright (c) 1992 by Integrated Computer Solutions, Inc.