Classes

The DtComboBox widget inherits behavior and resources from the Core, Composite and XmManager classes.

The class pointer is dtComboBoxWidgetClass.

The class name is DtComboBoxWidget.

New Resources

The following table defines a set of widget resources used by the application to specify data. The application 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, the application must remove the DtN or DtC prefix and use the remaining letters. To specify one of the defined values for a resource in a .Xdefaults file, the application must remove the Dt prefix and use the remaining letters (in either lower case or upper case, but including 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).

DtNmarginHeight

Specifies the number of pixels added between the top and bottom of the text widget and the start of the shadow.

DtNmarginWidth

Specifies the number of pixels added between the right and left sides of the text widget and the start of the shadow.

DtNselectedItem

This resource is passed through to the XmList to set the XmNselectedItemCount and XmNselectedItems as the single item in the XmNitems that matches this specified XmString in the List. Setting both DtNselectedItem and DtNselectedPosition in the same argument list produces undefined behavior.

DtNselectedPosition

This resource is passed through to the XmList to set the XmNselectedItemCount and XmNselectedItems as the single item at this specified position in the List. Setting both DtNselectedItem and DtNselectedPosition in the same argument list produces undefined behavior.

DtNselectionCallback

This callback list is issued when an item is selected from the DtComboBox widget's List. The call_data structure contains a DtComboBoxCallbackStruct with the reason DtCR_SELECT.

DtNcomboBoxType

This resource determines the style of the DtComboBox. There are two choices:

Inherited Resources

The DtComboBox widget inherits behavior and resources from the following named superclasses. For a complete description of each resource, see the man page for that superclass.

Callback Information

A pointer to the following structure is passed to each DtComboBox callback:

typedef struct {


        int             reason;


        XEvent          *event;


        XmString        item_or_text;


        int             item_position;
} DtComboBoxCallbackStruct;

The reason argument indicates why the callback was invoked; it is always DtCR_SELECT.

The event argument points to the XEvent that triggered the callback, or NULL if the callback was not triggered by an XEvent.

The item_or_text argument is the contents of the Text widget at the time the event caused the callback to be invoked. This data is only valid within the scope of the call_data structure, so the application must copy it when it is used outside of this scope.

The item_position argument is the new value of the DtNselectedPosition resource in the DtComboBox's List. If this is zero, it means the user entered a value in the XmTextField widget.