3392l1.orig100664 1061 330 22524 6725006372 11147 0ustar mlrljedit/* xtxtvw.c X11/Motif based text file viewer - example program meant to accompany Linux Journal article on Motif development the following command should build the application on most linux systems gcc -o xtxtvw xtxtvw.c -I/usr/X11R6/include -L/usr/X11R6/lib -lXm -lXt -lX11 the following command should build the application on many Solaris systems gcc -o xtxtvw xtxtvw.c -I/usr/dt/include -L/usr/openwin/lib -lXm -lXt -lX11 */ #include #include #include #include #include #include #include #include /* for the menu widget */ #include #include #include /* the class is used to identify application resources */ const char *X_APP_CLASS = "XTxtVw"; /* reasonable default values for some essential resources */ const String FALLBACKRES[] = { "*background: grey" , "*forground: black" /* don't use * here otherwise all widgets will have these dimensions */ , "XTxtVw.width: 400" , "XTxtVw.height: 400" , NULL }; /* most applications have only 1 top level shell */ Widget g_topshell; /* the file selection dialog is invoked from multiple routines so it is easiest to make the widget global */ Widget g_filedlg; /* we use the widget to keep the file name */ Widget g_filenamew; /* we would like to alter the text display from many routines so... */ Widget g_filetextw; /* callback routine names are suffixed with CB by convention */ void fileCB(Widget widget, XtPointer client_data, XtPointer call_data); void readfileCB(Widget widget, XtPointer client_data, XtPointer call_data); void fileselCB(Widget widget, XtPointer client_data, XtPointer call_data); void file_okCB(Widget widget, XtPointer client_data, XtPointer call_data); void setMainTitle(char *fn); /*---------------------------------------- main */ int main(int argc, char *argv[]) { XtAppContext app; Widget menubar; Widget form; Widget label; Widget browseb; Widget w; XmString xms_file; XmString xms_open; XmString xms_exit; XmString xms_openacc; XmString xms_exitacc; char *fn; Arg args[10]; int nargs; /* initialize toolkit and create top level shell */ XtSetLanguageProc(NULL, NULL, NULL); g_topshell = XtAppInitialize(&app, X_APP_CLASS, NULL, 0, &argc, argv , (String *) FALLBACKRES, NULL, 0); /* enable editres support */ XtAddEventHandler(g_topshell, (EventMask) 0, True , (XtEventHandler) _XEditResCheckMessages, 0); setMainTitle(NULL); /* handle command line arguments that remain - Xt has already taken care of any arguments intended for it, what remains is yours */ if(argc > 1) fn = argv[1]; /* build GUI components */ form = XmCreateForm(g_topshell, "form", NULL, 0); /* build the menu bar */ /* most of the strings that get displayed by Motif are handled as the XmString type in order to support localization */ xms_file = XmStringCreateLocalized("File"); /* XmVa* functions require a trailing 'NULL' argument */ menubar = XmVaCreateSimpleMenuBar(form, "menubar" , XmVaCASCADEBUTTON, xms_file, 'F' , XmNtopAttachment, XmATTACH_FORM , XmNleftAttachment, XmATTACH_FORM , XmNrightAttachment, XmATTACH_FORM , NULL); /* if Motif Creates or Gets an XmString then you must normally explicitly release the associated storage */ XmStringFree(xms_file); /* build the File pulldown menu */ xms_open = XmStringCreateLocalized("Open"); xms_openacc = XmStringCreateLocalized("Ctrl+O"); xms_exit = XmStringCreateLocalized("Exit"); xms_exitacc = XmStringCreateLocalized("Ctrl+X"); XmVaCreateSimplePulldownMenu(menubar, "filemenu", 0, fileCB , XmVaPUSHBUTTON, xms_open, 'O', "CtrlO", xms_openacc , XmVaSEPARATOR , XmVaPUSHBUTTON, xms_exit, 'x', "CtrlX", xms_exitacc , NULL); XmStringFree(xms_open); XmStringFree(xms_exit); XtManageChild(menubar); /* build file selection dialog that will be used by the Browse button */ g_filedlg = XmCreateFileSelectionDialog(g_topshell, "filesb", NULL, 0); XtAddCallback(g_filedlg, XmNokCallback, fileselCB, NULL); XtAddCallback(g_filedlg, XmNcancelCallback, fileselCB, NULL); w = XmSelectionBoxGetChild(g_filedlg, XmDIALOG_HELP_BUTTON); XtUnmanageChild(w); w = XmSelectionBoxGetChild(g_filedlg, XmDIALOG_APPLY_BUTTON); XtUnmanageChild(w); /* build the filename entry/display area */ label = XtVaCreateManagedWidget("Filename: ", xmLabelGadgetClass, form , XmNtopAttachment, XmATTACH_WIDGET , XmNtopWidget, menubar , XmNtopOffset, 10 , XmNleftAttachment, XmATTACH_FORM , NULL); g_filenamew = XtVaCreateManagedWidget("filename", xmTextFieldWidgetClass, form , XmNtopAttachment, XmATTACH_WIDGET , XmNtopWidget, menubar , XmNtopOffset, 5 , XmNleftAttachment, XmATTACH_WIDGET , XmNleftWidget, label , XmNleftOffset, 2 , NULL); browseb = XtVaCreateManagedWidget("Browse", xmPushButtonWidgetClass, form , XmNtopAttachment, XmATTACH_WIDGET , XmNtopWidget, menubar , XmNtopOffset, 6 , XmNrightAttachment, XmATTACH_FORM , XmNrightOffset, 10 , NULL); XtVaSetValues(g_filenamew , XmNrightAttachment, XmATTACH_WIDGET , XmNrightWidget, browseb , XmNrightOffset, 10 , NULL); /* build the file contents area */ /* an alternative to using the XmVa*() is to build an argument list and passing it to the function. I have noticed that sometimes Lesstif/gcc and the XmVa*() functions can choke the compiler */ nargs = 0; XtSetArg(args[nargs], XmNtopAttachment, XmATTACH_WIDGET); nargs++; XtSetArg(args[nargs], XmNtopWidget, g_filenamew); nargs++; XtSetArg(args[nargs], XmNleftAttachment, XmATTACH_FORM); nargs++; XtSetArg(args[nargs], XmNrightAttachment, XmATTACH_FORM); nargs++; XtSetArg(args[nargs], XmNbottomAttachment, XmATTACH_FORM); nargs++; XtSetArg(args[nargs], XmNeditable, False); nargs++; XtSetArg(args[nargs], XmNeditMode, XmMULTI_LINE_EDIT); nargs++; g_filetextw = XmCreateScrolledText(form, "filetext", args, nargs); XtManageChild(g_filetextw); /* tie in some callbacks to make this thing live */ XtAddCallback(g_filenamew, XmNactivateCallback, readfileCB, NULL); XtAddCallback(browseb, XmNactivateCallback, fileCB, NULL); /* start up the X event loop and expose the GUI */ XtManageChild(form); XtRealizeWidget(g_topshell); XtAppMainLoop(app); return 0; } /* main */ /*---------------------------------------- fileCB file menu callback client_data is a reserved for your use normally, call_data is typically valued by Motif - see fileselCB */ void fileCB(Widget widget, XtPointer client_data, XtPointer call_data) { static Widget filename; int menuitem; if(call_data == NULL) { filename = (Widget) client_data; return; } menuitem = (int) client_data; switch(menuitem) { case 0: /* open */ XtManageChild(g_filedlg); break; case 1: /* exit */ exit(0); break; default: break; } /* switch */ return; } /* fileCB */ /*---------------------------------------- fileselCB callback used by the action buttons in the file selection dialog Motif callbacks usually populate the call_data parameter with a widget specific Callback structure, in this case it is a superset of XmSelectionBoxCallbackStruct (the first few members are identical) */ void fileselCB(Widget widget, XtPointer client_data, XtPointer call_data) { char *fn; int allswell = 0; XmFileSelectionBoxCallbackStruct *cbs; cbs = (XmFileSelectionBoxCallbackStruct *) call_data; if(cbs->reason == XmCR_OK) { if(!XmStringGetLtoR(cbs->value, XmFONTLIST_DEFAULT_TAG, &fn)) return; if(strlen(fn) > 0 && access(fn, R_OK) == 0) { XmTextFieldSetString(g_filenamew, fn); allswell = 1; } XtFree(fn); } /* dialog will disappear but it is not deallocated - may need it later */ XtUnmanageChild(g_filedlg); if(allswell) { XmUpdateDisplay(g_topshell); readfileCB(NULL, NULL, NULL); } return; } /* fileselCB */ /*---------------------------------------- readfileCB callback used to trigger file-read invoked by user pressing Enter on the filename text field or by selecting OK from the file selection box */ void readfileCB(Widget widget, XtPointer client_data, XtPointer call_data) { const int bufsz = 1024; FILE *fh; char *fn; char buf[bufsz]; char *txt; char *msg; int pos = 0; /* clear the text display */ XmTextSetString(g_filetextw, ""); fn = XmTextFieldGetString(g_filenamew); fh = fopen(fn, "r"); if(fh) { setMainTitle(fn); while(fgets(buf, bufsz, fh)) { XmTextInsert(g_filetextw, pos, buf); pos += strlen(buf); } fclose(fh); } else { msg = (char *) malloc(strlen(fn) + 9); sprintf(msg, "fopen (%s)", fn); perror(msg); free(msg); } XtFree(fn); return; } /* readfileCB */ /*---------------------------------------- setMainTitle set the application title - icon titles should also be assigned here */ void setMainTitle(char *fn) { Arg args[3]; int nargs = 0; char title[256]; char *p = NULL; /* strip any path info from the filename */ if(fn) { p = strrchr(fn, '/'); if(p) p++; else p = fn; } sprintf(title, "xTxtVw%s%s", (p ? ": " : ""), (p ? p : "")); XtSetArg(args[nargs], XmNtitle, title); nargs++; XtSetArg(args[nargs], XmNiconName, title); nargs++; XtSetValues(g_topshell, args, nargs); return; } /* setMainTitle */ /* xtxtvw.c */