XmCommand

library call

`XmCommand`

The Command widget class

    &npzwc;#include <Xm/Command.h>

## DESCRIPTION

Command is a special-purpose composite widget for command entry that provides a built-in command-history mechanism. Command includes a command-line text-input field, a command-line prompt, and a command-history list region.

One additional `WorkArea` child may be added to the Command after creation.

Whenever a command is entered, it is automatically added to the end of the command-history list and made visible. This does not change the selected item in the list, if there is one.

Many of the new resources specified for Command are actually SelectionBox resources that have been renamed for clarity and ease of use.

### Descendants

Command 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`
=
`ItemsList` | `XmList` | command-history list region
`ItemsListSW` | `XmScrolledWindow` | the ScrolledWindow parent of `ItemsList`
`Selection` | `XmLabelGadget` | command-line prompt
`Text` | `XmTextField` | command-line text-input field

### Classes

Command inherits behavior, resources, and traits from `Core`, `Composite`, `Constraint`, `XmManager`, `XmBulletinBoard`, and `XmSelectionBox`.

The class pointer is xmCommandWidgetClass.

The class name is `XmCommand`.

### 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).

`XmCommand Resource Set`
`Name` | `Class` | `Type` | `Default` | `Access`
XmNcommand | XmCTextString | XmString | "" | CSG
XmNcommandChangedCallback | XmCCallback | XtCallbackList | NULL | C
XmNcommandEnteredCallback | XmCCallback | XtCallbackList | NULL | C
XmNhistoryItems | XmCItems | XmStringTable | NULL | CSG
XmNhistoryItemCount | XmCItemCount | int | 0 | CSG
XmNhistoryMaxItems | XmCMaxItems | int | 100 | CSG
XmNhistoryVisibleItemCount | XmCVisibleItemCount | int | dynamic | CSG
XmNpromptString | XmCPromptString | XmString | dynamic | CSG

`XmNcommand`

- Contains the current command-line text. This is the `XmNtextString` resource in SelectionBox, renamed for Command. This resource can also be modified with `XmCommandSetValue` and `XmCommandAppendValue` functions. The command area is a Text widget.

`XmNcommandChangedCallback`

- Specifies the list of callbacks that is called after each time the value of the command changes. The callback reason is `XmCR_COMMAND_CHANGED`. This is equivalent to the `XmNvalueChangedCallback` of the Text widget, except that a pointer to an XmCommandCallbackStructure is passed, and the structure's value member contains the XmString.

`XmNcommandEnteredCallback`

- Specifies the list of callbacks that is called when a command is entered in the Command. The callback reason is `XmCR_COMMAND_ENTERED`. A pointer to an XmCommandCallback structure is passed.

`XmNhistoryItems`

- Lists XmString items that make up the contents of the history list. This is the `XmNlistItems` resource in SelectionBox, renamed for Command. `XtGetValues` for this resource returns the list items themselves, not a copy of the list items. The application must not free the returned items.

`XmNhistoryItemCount`

- Specifies the number of XmStrings in `XmNhistoryItems`. This is the `XmNlistItemCount` resource in SelectionBox, renamed for Command. The value must not be negative.

`XmNhistoryMaxItems`

- Specifies the maximum number of items allowed in the history list. Once this number is reached, an existing list item must be removed before a new item can be added to the list. For each command entered, the first list item is removed from the list, so the new command can be added to the list. The value must be greater than 0 (zero).

`XmNhistoryVisibleItemCount`

- Specifies the number of items in the history list that should be visible at one time. In effect, it sets the height (in lines) of the history list window. This is the `XmNlistVisibleItemCount` resource in SelectionBox, renamed for Command. The value must be greater than 0 (zero). The default is dynamic based on the height of the list.

`XmNpromptString`

- Specifies a prompt for the command line. This is the `XmNselectionLabelString` resource in SelectionBox, renamed for Command. The default may vary depending on the value of the `XmNlayoutDirection` resource and the locale. In the C locale the default is > (right angle bracket).

  Now that some default localized label strings are provided through message catalogs for the children of composite widgets, the `labelString` resources cannot be set on the child through default resource files. Instead, the resource provided at the parent level must be used.

### Inherited Resources

Command 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.

`XmSelectionBox Resource Set`
`Name` | `Class` | `Type` | `Default` | `Access`
XmNapplyCallback | XmCCallback | XtCallbackList | NULL | N/A
XmNapplyLabelString | XmCApplyLabelString | XmString | dynamic | N/A
XmNcancelCallback | XmCCallback | XtCallbackList | NULL | N/A
XmNcancelLabelString | XmCCancelLabelString | XmString | dynamic | N/A
XmNchildPlacement | XmCChildPlacement | unsigned char | XmPLACE_ABOVE_SELECTION | CSG
XmNdialogType | XmCDialogType | unsigned char | XmDIALOG_COMMAND | G
XmNhelpLabelString | XmCHelpLabelString | XmString | dynamic | N/A
XmNlistItemCount | XmCItemCount | int | 0 | CSG
XmNlistItems | XmCItems | XmStringTable | NULL | CSG
XmNlistLabelString | XmCListLabelString | XmString | NULL | N/A
XmNlistVisibleItemCount | XmCVisibleItemCount | int | dynamic | CSG
XmNminimizeButtons | XmCMinimizeButtons | Boolean | False | N/A
XmNmustMatch | XmCMustMatch | Boolean | False | N/A
XmNnoMatchCallback | XmCCallback | XtCallbackList | NULL | N/A
XmNokCallback | XmCCallback | XtCallbackList | NULL | N/A
XmNokLabelString | XmCOkLabelString | XmString | dynamic | N/A
XmNselectionLabelString | XmCSelectionLabelString | XmString | dynamic | CSG
XmNtextAccelerators | XmCTextAccelerators | XtAccelerators | default | C
XmNtextColumns | XmCColumns | short | dynamic | CSG
XmNtextString | XmCTextString | XmString | "" | CSG

`XmBulletinBoard Resource Set`
`Name` | `Class` | `Type` | `Default` | `Access`
XmNallowOverlap | XmCAllowOverlap | Boolean | True | CSG
XmNautoUnmanage | XmCAutoUnmanage | Boolean | False | N/A
XmNbuttonFontList | XmCButtonFontList | XmFontList | dynamic | N/A
XmNbuttonRenderTable | XmCButtonRenderTable | XmRenderTable | dynamic | CSG
XmNcancelButton | XmCWidget | Widget | NULL | N/A
XmNdefaultButton | XmCWidget | Widget | NULL | N/A
XmNdefaultPosition | XmCDefaultPosition | Boolean | False | CSG
XmNdialogStyle | XmCDialogStyle | unsigned char | dynamic | CSG
XmNdialogTitle | XmCDialogTitle | XmString | NULL | CSG
XmNfocusCallback | XmCCallback | XtCallbackList | NULL | C
XmNlabelFontList | XmCLabelFontList | XmFontList | dynamic | CSG
XmNlabelRenderTable | XmCLabelRenderTable | XmRenderTable | dynamic | CSG
XmNmapCallback | XmCCallback | XtCallbackList | NULL | C
XmNmarginHeight | XmCMarginHeight | Dimension | 10 | CSG
XmNmarginWidth | XmCMarginWidth | Dimension | 10 | CSG
XmNnoResize | XmCNoResize | Boolean | False | CSG
XmNresizePolicy | XmCResizePolicy | unsigned char | XmRESIZE_NONE | CSG
XmNshadowType | XmCShadowType | unsigned char | XmSHADOW_OUT | CSG
XmNtextFontList | XmCTextFontList | XmFontList | dynamic | CSG
XmNtextRenderTable | XmCTextRenderTable | XmRenderTable | dynamic | CSG
XmNtextTranslations | XmCTranslations | XtTranslations | NULL | C
XmNunmapCallback | XmCCallback | XtCallbackList | NULL | C

`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 | dynamic | CSG
XmNlayoutDirection | XmCLayoutDirection | XmDirection | dynamic | CG
XmNnavigationType | XmCNavigationType | XmNavigationType | XmTAB_GROUP | CSG
XmNpopupHandlerCallback | XmCCallback | XtCallbackList | NULL | C
XmNshadowThickness | XmCShadowThickness | Dimension | dynamic | 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 | N/A
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;
            XmString value;
            int length;
    } XmCommandCallbackStruct;

reason

- Indicates why the callback was invoked

event

- Points to the XEvent that triggered the callback

value

- Specifies the XmString in the CommandArea

length

- Specifies the size in bytes of the XmString value. This member is obsolete and exists for compatibility with earlier releases.

### Translations

`XmCommand` inherits translations from `XmSelectionBox`.

### Accelerators

The `XmNtextAccelerators` from `XmSelectionBox` are added to the Text descendant of `XmCommand`.

### Action Routines

The `XmCommand` action routines are:

SelectionBoxUpOrDown(Previous|Next|First|Last):

- When called with an argument of `Previous`, or 0 (zero) for compatibility, selects the previous item in the history list and replaces the text with that item.

  When called with an argument of `Next`, or 1 for compatibility, selects the next item in the history list and replaces the text with that item.

  When called with an argument of `First`, or 2 for compatibility, selects the first item in the history list and replaces the text with that item.

  When called with an argument of `Last`, or 3 for compatibility, selects the last item in the history list and replaces the text with that item.

  Calls the callbacks for `XmNcommandChangedCallback`.

### Additional Behavior

The Command widget has the following additional behavior:

Key osfCancel:

- If the parent of the Command is a manager, the event is passed to the parent.

Key osfActivatein Text:

- Calls the Text widget's `XmNactivateCallback` callbacks. If the text is empty, this action then returns. Otherwise, if the history list has `XmNhistoryMaxItems` items, it removes the first item in the list. It adds the text to the history list as the last item, clears the text, and calls the `XmNcommandEnteredCallback` callbacks.

Keyin Text:

- When any change is made to the text edit widget, this action calls the callbacks for `XmNcommandChangedCallback`.

BtnDown`(2+)`orKey osfActivatein List:

- Calls the List widget's `XmNdefaultActionCallback` callbacks. If the history list has `XmNhistoryMaxItems` items, this action removes the first item in the list. It adds the selected List item to the history list as the last item, clears the text, and calls the `XmNcommandEnteredCallback` callbacks.

FocusIn:

- Calls the callbacks for `XmNfocusCallback`.

MapWindow:

- When a Command that is the child of a DialogShell is mapped, this action calls the callbacks for `XmNmapCallback`.

UnmapWindow:

- When a Command that is the child of a DialogShell is unmapped, this action calls the callbacks for `XmNunmapCallback`.

### Virtual Bindings

The bindings for virtual keys are vendor specific. For information about bindings for virtual buttons and keys, see &cdeman.VirtualBindings;.

## RELATED

&cdeman.Composite;, &cdeman.Constraint;, &cdeman.Core;, &cdeman.XmBulletinBoard;, &cdeman.XmCommandAppendValue;, &cdeman.XmCommandError;, &cdeman.XmCommandGetChild;, &cdeman.XmCommandSetValue;, &cdeman.XmCreateCommand;, &cdeman.XmManager;, and &cdeman.XmSelectionBox;.