ArcGIS Engine Developer Guide

BUILDING APPLICATIONS WITH C++ AND CONTROL WIDGETS
XtResizeWidget(topLevel, 800, 640, 1);
Widget mainWindow = XtVaCreateWidget("mainwindow",
xmMainWindowWidgetClass, topLevel,
NULL);
Widget mainForm = XtVaCreateWidget("mainform",
xmFormWidgetClass, mainWindow,
XmNtopAttachment, XmATTACH_WIDGET,
XmNtopWidget, mainWindow,
XmNbottomAttachment, XmATTACH_WIDGET,
XmNbottomWidget, mainWindow,
XmNleftAttachment, XmATTACH_WIDGET,
XmNleftWidget, mainWindow,
XmNrightAttachment, XmATTACH_WIDGET,
XmNrightWidget, mainWindow,
XmNfractionBase, 100,
NULL);
d. Manage the child widgets.
Widget mainForm = XtVaCreateWidget(…);
// Manage the non-parent widgets
XtManageChild(mainWindow);
XtManageChild(mainForm);
e. Listen for window manager events to exit the application on command. To
set this up, you will use a callback on the entire application that will respond
to window manager protocols. When the window manager’s close
message is received, the CloseAppCallback function is executed. Here just
listen—you will implement the callback function in Step 9.
XtManageChild(mainForm);
GTK deals with closing differently, as shown in
form_setup of GTK’s MapViewer.cpp.
// Handle the "close" window manager message
Atom wm_delete_window = XmInternAtom(XtDisplay(topLevel),
"WM_DELETE_WINDOW", FALSE);
XmAddWMProtocolCallback(topLevel,
wm_delete_window, CloseAppCallback,
NULL);
f. With all the application widgets created and managed and all the callbacks
registered, the application can start running. Realizing the top-level widget
recursively creates the actual windows for all the application widgets. The
call to the function is made at the end of your FormSetup function.
void FormSetup(…)
{
…
XmAddWMProtocolCallback(topLevel,
wm_delete_window, CloseAppCallback,
NULL);
Chapter 6 • Developer scenarios • 363