Volume 6A: Motif Programming Manual

callback routines. This interactivity is the principal difference between PushButtons and Labels. There are other visual

differences, but these are adjusted automatically by the PushButton widget using Label resources.

<Xm/PushB.h> and <Xm/PushBG.h> are the header files for PushButton widgets and gadgets, respectively. These

objects can be created using XtVaCreateManagedWidget(), as in the following code fragment:

Widget pushb_w, pushb_g;

pushb_w = XtVaCreateManagedWidget ("name",

xmPushButtonWidgetClass, parent,

resource−value−list,

NULL);

pushb_g = XtVaCreateManagedWidget ("name",

xmPushButtonGadgetClass, parent,

resource−value−list,

NULL);

12.2.1 PushButton Callbacks

The major callback routine associated with the PushButton widget is the XmNactivateCallback. The functions

associated with this resource are called whenever the user activates the PushButton by pressing the left mouse button

over it or by pressing the SPACEBAR when the widget has the keyboard focus.

The other callback routines associated with the PushButton are the XmNarmCallback and the

XmNdisarmCallback. Each function in an arm callback list is called whenever the user presses the left mouse

button when the pointer is over the PushButton. When the PushButton is armed, the top and bottom shadows are

inverted and the background of the button changes to the arm color. The arm callback does not indicate that the button

has been released. If the user releases the mouse button within the widget, then the activate callback list ...