WwCallback Function (Motif Only)

Reference Guide > W Routines > WwCallback Function (Motif Only)

Adds or removes a PV‑WAVE Widgets callback.

Usage

status = WwCallback(wid, callback, reason, client_data)

Input Parameters

wid — The ID of the widget for which to add or remove the callback.

callback — A string containing the name of the PV‑WAVE callback routine.

reason — A string containing the callback reason. (See the Discussion section for more information.)

client_data — A variable. The value of this variable is passed to the callback routine.

Returned Value

status — A value indicating success or failure of the addition or removal of the PV‑WAVE Widgets callback.

1 — Indicates success.

0 — Indicates failure.

Keywords

Add — If nonzero, the specified callback is added.

Params — If nonzero, the callback is called with all parameters. (Default: called with only the wid and data parameters; see the Callback Parameters section)

Remove — If nonzero, the specified callback is removed.

Callback Parameters

Any added callback procedure must have the following two parameters:

wid — The widget ID.

data — User-defined data.

Discussion

Callback reasons are listed throughout the OSF/Motif Programmer’s Reference.

note

Rogue Wave has ported a subset of the Motif widget functionality to Microsoft Windows. To use WwCallback, you must refer to the OSF/Motif Programmer’s Reference to obtain callback reasons. Because Motif widgets are only partly implemented for Windows, some callback reasons are not available for use in Windows applications.

To use a Motif callback reason in PV‑WAVE, remove the XmN or XtN prefix. For example, the Motif name, XmNactivateclllpockd, becomes the PV‑WAVE widgets name, activateCallback.

Use of the client_data parameter is optional in the application. It can specify some application-defined data to be passed to the callback procedure when the callback is invoked. If client_data is a local variable (defined only in the current procedure), a copy of that variable is created and passed by value. If client_data is a global variable (defined in a Common Block), it is passed by reference.