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Subject: Motif FAQ (Part 3 of 6) Newsgroups: comp.windows.x.motif,comp.answers,news.answers From: ksall@cen.com (Ken Sall) Date: 11 Oct 1994 07:52:00 GMT Archive-name: motif-faq/part3 Last-modified: OCT 10, 1994 Posting-Frequency: monthly Organization: Century Computing, Inc. Version: 3.8 ----------------------------------------------------------------------------- Subject: 59) How can I replace characters typed with say a `*'? I want to replace input for password entry. [Last modified: April 93] Answer: In Motif 1.1 Use the modifyVerifyCallback to tell when input is received. Set text->ptr in the callback structure to '*'. This does not work under 1.0 because of an oversight in which changes to this are ignored. In Motif 1.0, what you can do is set the doit flag to 'false' so the text is not displayed. Then set a static boolean to True to prevent re-entrance. Next call XmTextReplace() to display your '*'. then reset your re-entrance flag to False. XmTextReplace() will call the XmNmodifyVerify callback. To prevent getting into an infinite loop, you need the re-entrance flag. The following program from Dan Heller illustrates this: -------------- /* Written by Dan Heller. Copyright 1991, O'Reilly && Associates. * This program is freely distributable without licensing fees and * is provided without guarantee or warranty expressed or implied. * This program is -not- in the public domain. This program appears * in the Motif Programming Manual, O'Reilly Volume 6. */ /* passwd.c -- prompt for a passwd. Meaning, all input looks like * a series of *'s. Store the actual data typed by the user in * an internal variable. Don't allow paste operations. Handle * backspacing by deleting all text from insertion point to the * end of text. */ #include <Xm/Text.h> #include <Xm/LabelG.h> #include <Xm/RowColumn.h> #include <ctype.h> void check_passwd(); char *passwd; /* store user-typed passwd here. */ main(argc, argv) int argc; char *argv[]; { Widget toplevel, text_w, rowcol; XtAppContext app; toplevel = XtVaAppInitialize(&app, "Demos", NULL, 0, &argc, argv, NULL, NULL); rowcol = XtVaCreateWidget("rowcol", xmRowColumnWidgetClass, toplevel, XmNorientation, XmHORIZONTAL, NULL); XtVaCreateManagedWidget("Password:", xmLabelGadgetClass, rowcol, NULL); text_w = XtVaCreateManagedWidget("text_w", xmTextWidgetClass, rowcol, NULL); XtAddCallback(text_w, XmNmodifyVerifyCallback, check_passwd, NULL); XtAddCallback(text_w, XmNactivateCallback, check_passwd, NULL); XtManageChild(rowcol); XtRealizeWidget(toplevel); XtAppMainLoop(app); } void check_passwd(text_w, unused, cbs) Widget text_w; XtPointer unused; XmTextVerifyCallbackStruct *cbs; { char *new; int len; if (cbs->reason == XmCR_ACTIVATE) { printf("Password: %s\n", passwd); return; } if (cbs->text->ptr == NULL) { /* backspace */ cbs->endPos = strlen(passwd); /* delete from here to end */ if (cbs->endPos <= 0) return; /* catch null passwd - Mark Scoville */ passwd[cbs->startPos] = 0; /* backspace--terminate */ return; } if (cbs->text->length > 1) { cbs->doit = False; /* don't allow "paste" operations */ return; /* make the user *type* the password! */ } new = XtMalloc(cbs->endPos + 2); /* new char + NULL terminator */ if (passwd) { strcpy(new, passwd); XtFree(passwd); } else new[0] = NULL; passwd = new; strncat(passwd, cbs->text->ptr, cbs->text->length); passwd[cbs->endPos + cbs->text->length] = 0; for (len = 0; len < cbs->text->length; len++) cbs->text->ptr[len] = '*'; } ----------------------------------------------------------------------------- Subject: 60) How can I best add a large piece of text to a scrolled text widget? [Last modified: Sept 94] [NOTE: This problem is probably only relevant for Motif 1.0 which probably no one is using anymore. If you know this to still be a problem, send mail to ksall@cen.com. I'll probably remove this question otherwise.] In some versions of Motif 1.0 even using XmTextSetString, it insists on adding the text one line at a time, adjusting the scroll bar each time. It looks awful and is slow. Answer: If you don't have this problem, use XmTextSetString to set all of the text in the widget. If you do have this slowdown problem even using XmTextSetString, unmanage the widget, add the text and then manage it again. This may cause the window to blink, but you have to put up with that or switch to a different version of Motif. ----------------------------------------------------------------------------- Subject: 61) How can I highlight text in the Text widget? Answer: From: argv@zipcode.com (Dan Heller) If you don't need font or color changes, you can do all this using a Text widget very easily [in Motif 1.1, anyway]. loop() { pos = offset_of_pattern_in_text_widget(pattern, text_w); search_len = strlen(pattern); XmTextSetHighlight(text_w, pos, pos+search_len, XmHIGHLIGHT_SELECTED); } There are two choices for highlighting: reverse video (HIGHLIGHT_SELECTED) and underlined (HIGHLIGHT_SECONDARY_SELECTED). Be careful that your users won't confuse your highlights with actual selections! ----------------------------------------------------------------------------- Subject: 62) How can I select all of the text in a widget programmatically? So that some initial text is displayed, but anything typed replaces it. Answer: XmTextSetSelection(Text1, 0, XmTextGetLastPosition(Text1), event- >xbutton.time); where Text1 is the widget in question (obviously) and event is some event that triggered this call. You can use XtLastTimestampProcessed( display) instead of xbutton.time if you don't happen to have an event pointer handy. ----------------------------------------------------------------------------- Subject: 63) How can I change colours of text in the Text widget? I want some of the text in one colour, some in another. Answer: You can't. Text stores an ordinary string, and points where `highlights' of various types begin and end. These highlights are all the control you have over components of the text. See the previous question. ----------------------------------------------------------------------------- Subject: 64) How can I change the font of text in the Text widget? I want some of the text in one font, some in another. [Last modified: Sept 94] Answer: You can't in Text (see the previous question). If you wanted readonly text, you could do it by using a label instead. Label uses XmStrings, which can contain multiple character sets in the one string. If you are using Motif 2.0, however, XmStrings are now permitted in XmText widgets, which solves this particular problem. ----------------------------------------------------------------------------- Subject: 65) Is there an emacs binding for the text widget? Answer: This set is due to Kee Hinckley (nazgul@utopia.com): *XmText.translations: #override\n\ Ctrl <Key>b: backward-character()\n\ Alt <Key>b: backward-word()\n\ Meta <Key>b: backward-word()\n\ Shift Alt <Key>b: backward-word(extend)\n\ Shift Meta <Key>b: backward-word(extend)\n\ Alt <Key>[: backward-paragraph()\n\ Meta <Key>[: backward-paragraph()\n\ Shift Alt <Key>[: backward-paragraph(extend)\n\ Shift Meta <Key>[: backward-paragraph(extend)\n\ Alt <Key><: beginning-of-file()\n\ Meta <Key><: beginning-of-file()\n\ Ctrl <Key>a: beginning-of-line()\n\ Shift Ctrl <Key>a: beginning-of-line(extend)\n\ Ctrl <Key>osfInsert: copy-clipboard()\n\ Shift <Key>osfDelete: cut-clipboard()\n\ Shift <Key>osfInsert: paste-clipboard()\n\ Alt <Key>>: end-of-file()\n\ Meta <Key>>: end-of-file()\n\ Ctrl <Key>e: end-of-line()\n\ Shift Ctrl <Key>e: end-of-line(extend)\n\ Ctrl <Key>f: forward-character()\n\ Alt <Key>]: forward-paragraph()\n\ Meta <Key>]: forward-paragraph()\n\ Shift Alt <Key>]: forward-paragraph(extend)\n\ Shift Meta <Key>]: forward-paragraph(extend)\n\ Ctrl Alt <Key>f: forward-word()\n\ Ctrl Meta <Key>f: forward-word()\n\ Ctrl <Key>d: kill-next-character()\n\ Alt <Key>BackSpace: kill-previous-word()\n\ Meta <Key>BackSpace: kill-previous-word()\n\ Ctrl <Key>w: key-select() kill-selection()\n\ Ctrl <Key>y: unkill()\n\ Ctrl <Key>k: kill-to-end-of-line()\n\ Alt <Key>Delete: kill-to-start-of-line()\n\ Meta <Key>Delete: kill-to-start-of-line()\n\ Ctrl <Key>o: newline-and-backup()\n\ Ctrl <Key>j: newline-and-indent()\n\ Ctrl <Key>n: next-line()\n\ Ctrl <Key>osfLeft: page-left()\n\ Ctrl <Key>osfRight: page-right()\n\ Ctrl <Key>p: previous-line()\n\ Ctrl <Key>g: process-cancel()\n\ Ctrl <Key>l: redraw-display()\n\ Ctrl <Key>osfDown: next-page()\n\ Ctrl <Key>osfUp: previous-page()\n\ Ctrl <Key>space: set-anchor()\n ! If you'd like the Delete key to work like backspace instead of deleting ! backwards, add the following definition to the lines above. ! <Key>osfDelete: delete-previous-character()\n\ ! These aren't included because they could intefere with | menu accelerators (or vice versa) ! Alt <Key>p: backward-paragraph()\n\ ! Meta <Key>p: backward-paragraph()\n\ ! Shift Alt<Key>p: backward-paragraph(extend)\n\ ! Shift Meta<Key>p: backward-paragraph(extend)\n\ ! Alt <Key>w: copy-clipboard()\n\ ! Meta <Key>w: copy-clipboard()\n\ ! Ctrl Alt <Key>w: cut-clipboard()\n\ ! Ctrl Meta <Key>w: cut-clipboard()\n\ ! Alt <Key>y: paste-clipboard()\n\ ! Meta <Key>y: paste-clipboard()\n\ ! Alt <Key>f: forward-word()\n\ ! Meta <Key>f: forward-word()\n\ ! Alt <Key>n: forward-paragraph()\n\ ! Meta <Key>n: forward-paragraph()\n\ ! Shift Alt <Key>n: forward-paragraph(extend)\n\ ! Shift Meta <Key>n: forward-paragraph(extend)\n\ ! Shift Alt <Key>f: forward-word(extend)\n\ ! Shift Meta <Key>f: forward-word(extend)\n\ ! Alt <Key>d: kill-next-word()\n\ ! Meta <Key>d: kill-next-word()\n\ ! Alt <Key>h: select-all()\n\ ! Meta <Key>h: select-all()\n\ Similar sets of translations have been suggested by others. ----------------------------------------------------------------------------- Subject: 66) How can I use a file as the text source for a Text widget? Answer: You can't do it directly like you can with the Athena Text widget. Instead, read the text from the file into a string (all of it!) and then use XmTextSetString. Alternatively, read blocks of characters and add them at the end of the text using XmTextInsertString. The following is an excerpt from Dan Heller's "file_browser.c": /* file_browser.c -- use a ScrolledText object to view the * contents of arbitrary files chosen by the user from a * FileSelectionDialog or from a single-line text widget. */ ... struct stat statb; /* make sure the file is a regular text file and open it */ if (stat(filename, &statb) == -1 || (statb.st_mode & S_IFMT) != S_IFREG || !(fp = fopen(filename, "r"))) { if ((statb.st_mode & S_IFMT) == S_IFREG) perror(filename); /* send to stderr why we can't read it */ else fprintf(stderr, "%s: not a regular file0, filename); XtFree(filename); return; } /* put the contents of the file in the Text widget by allocating * enough space for the entire file, reading the file into the * allocated space, and using XmTextFieldSetString() to show the file. */ if (!(text = XtMalloc((unsigned)(statb.st_size+1)))) { fprintf(stderr, "Can't alloc enough space for %s", filename); XtFree(filename); fclose(fp); return; } if (!fread(text, sizeof(char), statb.st_size+1, fp)) fprintf(stderr, "Warning: may not have read entire file!0); text[statb.st_size] = 0; /* be sure to NULL-terminate */ /* insert file contents in Text widget */ XmTextSetString(text_w, text); ----------------------------------------------------------------------------- Subject: 67) How can put Text in overstrike mode instead of insert? [Last modified: Sept 94] Answer: There is no direct way. This was posted by Edmond Pitt (ejp@bohra.cpg.oz) The correct answer to the question is to put the following in a modifyVerify callback, where 'mvcb' is the XmTextVerifyCallbackStruct, and 'overstriking' is defined by you: if (overstriking && mvcb->text->length == 1) { _XmTextDisableRedisplay(w,FALSE); XtCallActionProc(w,"delete-next-character",mvcb->event,0); _XmTextEnableRedisplay(w); } _XmText{Dis,En}ableRedisplay() are XmText{Dis,En}ableRedisplay() in 1.0, but X11R3 has no XtCallActionProc() anyway. For this environment you need my 1.0.3 Text widget patches posted last year & available on request. An update was provided by Ingeborg (inca@osf.org): In 1.2 and later releases, there is an action function toggle-overstrike() which will toggle between overstrike and insert mode. Before 1.2.3, there is no visual difference, and at most one character will get overstruck. In 1.2.3, a block cursor was added as a visual cue to that the widget is in overstrike mode, and the code was fixed to overstrike the actual number of characters input (this makes a difference if you have preediting - for example in japanese). There is no default binding in 1.2, but the recommended key is osfInsert without modifiers. No resource exists. ----------------------------------------------------------------------------- Subject: 68)* How can I make the Delete key do a Backspace? Related question: How can I swap Delete and Backspace? [Last modified: Oct 94] Answer: Put this in your .Xdefaults *XmText.translations: #override <Key>osfDelete: delete-previous-character() Additional information from David Kaelbling <drk@x.org>: You can also supply an arbitrary file name to xmbind (so you can conditionally run xmbind from your .xinitrc file based on the hostname, architecture, xdpyinfo output, or whatever). Some people prefer to use xmodmap to swap the keysyms for all applications, but what you're doing will work fine if you specify all of the virtual key bindings. The current bindings are stored on the root window -- use "xprop -root" and look for a _MOTIF_BINDINGS or _MOTIF_DEFAULT_BINDINGS property. OSF/Motif is also distributed with a "bindings" directory containing all the fallback virtkey binding files. There are several ways to do display-specific customization: make ----------------------------------------------------------------------------- Subject: 69) TOPIC: LIST WIDGET ----------------------------------------------------------------------------- Subject: 70) Should I create an XmList widget as a child of automatic XmScrolledWindow or use the XmCreateScrolledList() convenience function? Answer: With most implementations, the convenience function use internal hooks to give somewhat better scrolling performance. Thanks to Ken Lee, kenton@allegro.esd.sgi.com ----------------------------------------------------------------------------- Subject: 71) How do I best put a new set of items into a list? Answer: Set the new list count and list by XtSetArgs and install them by XtSetValues. XmString list[SIZE]; int list_size; XtSetArg (args[n], XmNitemCount, list_size); n++; XtSetArg (args[n], XmNitems, list); n++; XtSetValues (w, args, n); or similarly with XtVaSetValues: XtVaSetValues (w, XmNitemCount, list_size, XmNitems, list, NULL); Each time the list is reset by this the old contents are freed by the widget and the new supplied list is copied. Do *not* free the old list of items yourself as this would result in the space being freed twice. It is not necessary to remove the items one at a time, nor to "zero" out the list first. ----------------------------------------------------------------------------- Subject: 72) Can I have strings with different fonts in a list? Answer: Yes. The strings are XmStrings. Each one can be created using a different character set using a different font. ----------------------------------------------------------------------------- Subject: 73) Can I get a bitmap to show in a list item like I can in a Label? I want to place a bitmap along with some normal text in my list items. Answer: No. The list contains XmStrings, and these only allow text in various character sets. The workaround is to define your font containing the icons you want. Then you can create a fontlist containing your icon font and the font you want the text in, and then make your items multi-segment XmStrings where the first segment contains the code of the icon you want with a charset that matches the icon font in your fontlist and the second segment with a charset matching the text font. ----------------------------------------------------------------------------- Subject: 74) Can I have items with different colours in a list? Answer: No. The list contains XmStrings, and these only allow text in various character sets. Since the items are XmStrings, you can already change the font of an item by replacing it with an item with the same text and a different charset tag. Adding support for color would require modification of the internal data structure in XmList as well as modification to the drawing routines. A possible workaround is to use a rowcolumn of buttons which can be individually set. However, you would have to do all list functionality yourself. ----------------------------------------------------------------------------- Subject: 75) Can I grey out an item in a list? I want to make insensitive items in a list so that they cannot be selected. Answer: From W. Scott Meeks of OSF: Unfortunately, you can't do it directly since the list items aren't individual widgets. We've had other requests for this technology, but it didn't make the cut for 1.2; it should be in some future release. However, you can probably fake it in your application with some difficulty. First, a list item is an XmString, so you can specify a different charset for the item than for other items in the list and then specify a font in the list's fontlist that matches the charset and gives you the visual you want. The next problem is making the item unselectable. One idea would be to have the application keep track of the insensitive items and the items currently selected. Then you would set up a selection callback that when called would check the item selected against the list of insensitive items and if the selected item matched would deselect that item and reselect the previously selected items. Otherwise it would just update the application's list of selected items. The major drawback with this approach is that you'll get flashing whenever the list selects an item and your application immediately de-selects. Unfortunately I can't think of a way around this without mucking with the list internals. Another alternative suggested is to use instead a column of say read only text widgets which you can make insensitive. ----------------------------------------------------------------------------- Subject: 76) Can I have multi-line items in a list? [Last modified: August 92] Answer: Motif 1.0 and 1.1 both have problems with multi-line items in a list. They should work okay in Motif 1.2. ----------------------------------------------------------------------------- Subject: 77) How can I tell the position of selected items in a list? [Last modified: Oct 92] Answer: From W. Scott Meeks: 1) All XmList selection callbacks get an XmListCallbackStruct which includes the item selected and its position. In addition, the multiple and extended selection callbacks also get a list of the selected items. This approach requires that your application saves this information if you need it outside of the immediate callback. 2) At any time you can XtGetValues the XmNselectedItems and XmNselectedItemCount resources. The problem with this approach is that identical items may or may not show up in multiple times in this list and the position in the selectedItems list may not relate directly to the position in the items list. 3) You can call XmListGetSelectedPos on the list widget. This will return a list of the positions of all selected items. ----------------------------------------------------------------------------- Subject: 78) TOPIC: FILE SELECTION BOX WIDGET ----------------------------------------------------------------------------- Subject: 79) What is libPW.a and do I need it? My manual says I need to link in libPW.a to use the File Selection Box. I can't find it on my system. [Last modified: Sept 94] Answer: The libPW.a is the Programmers Workbench library which is an ATT product not included in Berkeley based systems, hence it is not found in SunOS or Ultrix, but is found on HP-UX (a Berkeley/ATT hybrid which chose ATT in this case). It contains the regex(3) routines (regcmp, regex). Some systems which don't have these in the libc.a need to link with -lPW. Some systems which have the regex(3) routines in there also have the libPW.a. If you have regex(3) in libc, and it works, don't link with libPW. If you don't have regex(3) in libc, and you don't have a libPW, then check some sites on the net for public domain replacements (several exist), or call your vendor. In most versions of Motif (see the doco), you can compile FileSB.c with -DNO_REGEX if you don't have it. Casper H.S. Dik (asper@fwi.uva.nl), Faculty of Mathematics & Computer Science, University of Amsterdam, sent this update for Solaris 2.x users: The regex and regcmp function are part of libgen in SVR4. Motif applications should be linked with -lgen. (However, some SVR4 implementations, especially those of vendors that once shipped SVR3 still contain libPW.) On Solaris 2.x system, you'll need libgen which is located in /usr/ccs/lib. ----------------------------------------------------------------------------- Subject: 80) What are these compile errors: Undefined symbol _regcmp and _regex? [Last modified: Sept 94] Answer: You need to link in the libPW or libgen library - see previous question. ----------------------------------------------------------------------------- Subject: 81) What's wrong with the Motif 1.0 File Selection Box? I can't set the directory, change the directory or get the file mask to work. Answer: The 1.0 File Selection Box is broken, and these don't work. They weren't fixed until Motif 1.04. Use these later versions of 1.0 or switch to Motif 1.1 where it changed a lot. Joe Hildebrand has a work-around for some of this: Before popping up an XmFileSelectionDialog, change to the directory you want. When a file is selected, check if it is a directory, so that we can change to it. i.e. static void show_file_box_CB(w, client_data, call_data) Widget w; Widget client_data; XmAnyCallbackStruct *call_data; { chdir("/users/hildjj/files"); XtManageChild(client_data); } static void val_save(w, client_data, call_data) Widget w; Widget client_data; XmSelectionBoxCallbackStruct *call_data; { struct stat buf; /* struct stat is defined in stat.h */ char *filename; /* get the file name from the FileSelectionBox */ filename = SmX(call_data->value); /* get the status of the file named filename, and put it into buf */ if (!stat(filename, &buf)) { /* if it's a directory */ /* if it's a directory */ if(S_ISDIR(buf.st_mode)) { /* change to that directory, and update the FileSelectionBox */ chdir(filename); XmFileSelectionDoSearch(w, NULL); } else /* if it's a regular file */ if(S_ISREG(buf.st_mode)) /* ask if it should be overwritten */ XtManageChild(valbox); else /* it's another kind of file. What type, i can't think of, but it might happen */ pop_up_error_box(client_data, "Error saving file"); } else /* we couldn't get the file status */ { /* if it's because the file doesn't exist, we're golden */ if (errno == ENOENT) save_file(); else /* there is some other problem getting the status. e.g. bad path */ pop_up_error_box(client_data, "Error saving file"); } } this still doesn't implement the file masking stuff. ----------------------------------------------------------------------------- Subject: 82) TOPIC: FORM WIDGET ----------------------------------------------------------------------------- Subject: 83) Why don't labels in a Form resize when the label is changed? I've got some labels in a form. The labels don't resize whenever the label string resource is changed. As a result, the operator has to resize the window to see the new label contents. I am using Motif 1.1. Answer: This problem may happen to any widget inside a Form widget. The problem was that the Form will resize itself when it gets geometry requests from its children. If its preferred size is not allowed, the Form will disallow all geometry requests from its children. The workaround is that you should set any ancestor of the Form to be resizable. For the shell which contains the Form you should set the shell resource XmNallowShellResize to be True (by default, it is set to FALSE). There is currently an inconsistency on how resizing is being done, and it may get fixed in Motif 1.2. From db@sunbim.be (Danny Backx) Basically what you have to do is set the XmNresizePolicy on the Form to XmRESIZE_NONE. The facts seem to be that XmRESIZE_NONE does NOT mean "do not allow resizes". You may also have to set XmNresizable on the form to True. ----------------------------------------------------------------------------- Subject: 84) How can I center a widget in a form? Answer: One of Motif's trickier questions. The problems are that: Form gives no support for centering, only for edge attachments, and the widget must stay in the center if the form or the widget is resized. Just looking at horizontal centering (vertical is similar) some solutions are: a. Use the table widget instead of Form. b. A hack free solution is from Dan Heller: /* Written by Dan Heller. Copyright 1991, O'Reilly && Associates. * This program is freely distributable without licensing fees and * is provided without guarantee or warranty expressed or implied. * This program is -not- in the public domain. This program is * taken from the Motif Programming Manual, O'Reilly Volume 6. */ /* corners.c -- demonstrate widget layout management for a * BulletinBoard widget. There are four widgets each labeled * top-left, top-right, bottom-left and bottom-right. Their * positions in the bulletin board correspond to their names. * Only when the widget is resized does the geometry management * kick in and position the children in their correct locations. */ #include <Xm/BulletinB.h> #include <Xm/PushBG.h> char *corners[] = { "Top-Left", "Top-Right", "Bottom-Left", "Bottom-Right", }; static void resize(); main(argc, argv) int argc; char *argv[]; { Widget toplevel, bboard; XtAppContext app; XtActionsRec rec; int i; /* Initialize toolkit and create toplevel shell */ toplevel = XtVaAppInitialize(&app, "Demos", NULL, 0, &argc, argv, NULL, NULL); /* Create your standard BulletinBoard widget */ bboard = XtVaCreateManagedWidget("bboard", xmBulletinBoardWidgetClass, toplevel, NULL); /* Set up a translation table that captures "Resize" events * (also called ConfigureNotify or Configure events). If the * event is generated, call the function resize(). */ rec.string = "resize"; rec.proc = resize; XtAppAddActions(app, &rec, 1); XtOverrideTranslations(bboard, XtParseTranslationTable("<Configure>: resize()")); /* Create children of the dialog -- a PushButton in each corner. */ for (i = 0; i < XtNumber(corners); i++) XtVaCreateManagedWidget(corners[i], xmPushButtonGadgetClass, bboard, NULL); XtRealizeWidget(toplevel); XtAppMainLoop(app); } /* resize(), the routine that is automatically called by Xt upon the * delivery of a Configure event. This happens whenever the widget * gets resized. */ static void resize(w, event, args, num_args) CompositeWidget w; /* The widget (BulletinBoard) that got resized */ XConfigureEvent *event; /* The event struct associated with the event */ String args[]; /* unused */ int *num_args; /* unused */ { WidgetList children; int width = event->width; int height = event->height; Dimension w_width, w_height; short margin_w, margin_h; /* get handle to BulletinBoard's children and marginal spacing */ XtVaGetValues(w, XmNchildren, &children, XmNmarginWidth, &margin_w, XmNmarginHeight, &margin_h, NULL); /* place the top left widget */ XtVaSetValues(children[0], XmNx, margin_w, XmNy, margin_h, NULL); /* top right */ XtVaGetValues(children[1], XmNwidth, &w_width, NULL); /* To Center a widget in the middle of the BulletinBoard (or Form), * simply call: * XtVaSetValues(widget, XmNx, (width - w_width)/2, XmNy, (height - w_height)/2, NULL); * and return. */ XtVaSetValues(children[1], XmNx, width - margin_w - w_width, XmNy, margin_h, NULL); /* bottom left */ XtVaGetValues(children[2], XmNheight, &w_height, NULL); XtVaSetValues(children[2], XmNx, margin_w, XmNy, height - margin_h - w_height, NULL); /* bottom right */ XtVaGetValues(children[3], XmNheight, &w_height, XmNwidth, &w_width, NULL); XtVaSetValues(children[3], XmNx, width - margin_w - w_width, XmNy, height - margin_h - w_height, NULL); } c. No uil solution has been suggested, because of the widget size problem ----------------------------------------------------------------------------- Subject: 85) How do I line up two columns of widgets of different types? I have a column of say label widgets, and a column of text widgets and I want to have them lined up horizontally. The problem is that they are of different heights. Just putting them in a form or rowcolumn doesn't line them up properly because the label and text widgets are of different height. If you want the geometry to look like this ------------------------------------- | -------------------------- | |a label |Some text || | -------------------------- | ------------------- | |a longer label |Some more text || | ------------------- | | ---------------- | |a very long label |Even more text || | ---------------- | ------------------------------------- try /* Written by Dan Heller. Copyright 1991, O'Reilly && Associates. * This program is freely distributable without licensing fees and * is provided without guarantee or warranty expressed or implied. * This program is -not- in the public domain. This program is * taken from the Motif Programming Manual, O'Reilly Volume 6. */ /* text_form.c -- demonstrate how attachments work in Form widgets. * by creating a text-entry form type application. */ #include <Xm/PushB.h> #include <Xm/PushBG.h> #include <Xm/LabelG.h> #include <Xm/Text.h> #include <Xm/Form.h> char *prompts[] = { "Name:", "Phone:", "Address:", "City:", "State:", "Zip:", }; main(argc, argv) int argc; char *argv[]; { Widget toplevel, mainform, subform, label, text; XtAppContext app; char buf[32]; int i; toplevel = XtVaAppInitialize(&app, "Demos", NULL, 0, &argc, argv, NULL, NULL); mainform = XtVaCreateWidget("mainform", xmFormWidgetClass, toplevel, NULL); for (i = 0; i < XtNumber(prompts); i++) { subform = XtVaCreateWidget("subform", xmFormWidgetClass, mainform, /* first one should be attached for form */ XmNtopAttachment, i? XmATTACH_WIDGET : XmATTACH_FORM, /* others are attached to the previous subform */ XmNtopWidget, subform, XmNleftAttachment, XmATTACH_FORM, XmNrightAttachment, XmATTACH_FORM, NULL); label = XtVaCreateManagedWidget(prompts[i], xmLabelGadgetClass, subform, XmNtopAttachment, XmATTACH_FORM, XmNbottomAttachment, XmATTACH_FORM, XmNleftAttachment, XmATTACH_FORM, XmNalignment, XmALIGNMENT_BEGINNING, NULL); sprintf(buf, "text_%d", i); text = XtVaCreateManagedWidget(buf, xmTextWidgetClass, subform, XmNtopAttachment, XmATTACH_FORM, XmNbottomAttachment, XmATTACH_FORM, XmNrightAttachment, XmATTACH_FORM, XmNleftAttachment, XmATTACH_WIDGET, XmNleftWidget, label, NULL); XtManageChild(subform); } /* Now that all the forms are added, manage the main form */ XtManageChild(mainform); XtRealizeWidget(toplevel); XtAppMainLoop(app); } If you resize horizontally it stretches the text widgets. If you resize vertically it leaves space under the bottom (if you don't resize, this is not problem). If you want the text widgets to be lined up on the left, as in ---------------------------------------- | ------------------- | | a label |Some text || | ------------------- | ------------------- | | a longer label |Some more text || | ------------------- | | ------------------- | |a very long label |Even more text || | ------------------- | ---------------------------------------- try this /* Written by Dan Heller. Copyright 1991, O'Reilly && Associates. * This program is freely distributable without licensing fees and * is provided without guarantee or warranty expressed or implied. * This program is -not- in the public domain. This program is * taken from the Motif Programming Manual, O'Reilly Volume 6. */ /* text_entry.c -- This demo shows how the RowColumn widget can be * configured to build a text entry form. It displays a table of * right-justified Labels and Text widgets that extend to the right * edge of the Form. */ #include <Xm/LabelG.h> #include <Xm/RowColumn.h> #include <Xm/Text.h> char *text_labels[] = { "Name:", "Phone:", "Address:", "City:", "State:", "Zip:", }; main(argc, argv) int argc; char *argv[]; { Widget toplevel, rowcol; XtAppContext app; char buf[8]; int i; toplevel = XtVaAppInitialize(&app, "Demos", NULL, 0, &argc, argv, NULL, NULL); rowcol = XtVaCreateWidget("rowcolumn", xmRowColumnWidgetClass, toplevel, XmNpacking, XmPACK_COLUMN, XmNnumColumns, XtNumber(text_labels), XmNorientation, XmHORIZONTAL, XmNisAligned, True, XmNentryAlignment, XmALIGNMENT_END, NULL); /* simply loop thru the strings creating a widget for each one */ for (i = 0; i < XtNumber(text_labels); i++) { XtVaCreateManagedWidget(text_labels[i], xmLabelGadgetClass, rowcol, NULL); sprintf(buf, "text_%d", i); XtVaCreateManagedWidget(buf, xmTextWidgetClass, rowcol, NULL); } XtManageChild(rowcol); XtRealizeWidget(toplevel); XtAppMainLoop(app); } This makes all objects exactly the same size. It does not resize in nice ways. If you want the text widgets lined up on the left, and the labels to be the size of the longest string, resizing nicely both horizontally and vertically, as in ------------------------------------- | ---------------- | | a label |Some text || | ---------------- | ---------------- | | a longer label |Some more text || | ---------------- | | ---------------- | |a very long label |Even more text || | ---------------- | ------------------------------------- Answer: Do this: to get the widgets lined up horizontally, use a form but place the widgets using XmATTACH_POSITION. In the example, attach the top of the first label to the form, the bottomPosition to 33 (33% of the height). Attach the topPosition of the second label to 33 and the bottomPosition to 66. Attach the topPosition of the third label to 66 and the bottom of the label to the form. Do the same with the text widgets. To get the label widgets lined up vertically, use the right attachment of XmATTACH_OPPOSITE_WIDGET: starting from the one with the longest label, attach widgets on the right to each other. In the example, attach the 2nd label to the third, and the first to the second. To get the text widgets lined up, just attach them on the left to the labels. To get the text in the labels aligned correctly, use XmALIGNMENT_END for the XmNalignment resource. /* geometry for label 2 */ n = 0; XtSetArg (args[n], XmNalignment, XmALIGNMENT_END); n++; XtSetArg (args[n], XmNleftAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNbottomAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNtopAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNtopPosition, 66); n++; XtSetValues (label[2], args, n); /* geometry for label 1 */ n = 0; XtSetArg (args[n], XmNalignment, XmALIGNMENT_END); n++; XtSetArg (args[n], XmNbottomAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNbottomPosition, 66); n++; XtSetArg (args[n], XmNtopAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNtopPosition, 33); n++; XtSetArg (args[n], XmNleftAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNrightAttachment, XmATTACH_OPPOSITE_WIDGET); n++; XtSetArg (args[n], XmNrightWidget, label[2]); n++; XtSetValues (label[1], args, n); /* geometry for label 0 */ n = 0; XtSetArg (args[n], XmNalignment, XmALIGNMENT_END); n++; XtSetArg (args[n], XmNbottomAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNbottomPosition, 33); n++; XtSetArg (args[n], XmNtopAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNleftAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNrightAttachment, XmATTACH_OPPOSITE_WIDGET); n++; XtSetArg (args[n], XmNrightWidget, label[1]); n++; XtSetValues (label[0], args, n); /* geometry for text 0 */ n = 0; XtSetArg (args[n], XmNtopAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNbottomAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNbottomPosition, 33); n++; XtSetArg (args[n], XmNrightAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNleftAttachment, XmATTACH_WIDGET); n++; XtSetArg (args[n], XmNleftWidget, label[0]); n++; XtSetValues (text[0], args, n); /* geometry for text 1 */ XtSetArg (args[n], XmNtopAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNtopPosition, 33); n++; XtSetArg (args[n], XmNbottomAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNbottomPosition, 66); n++; XtSetArg (args[n], XmNrightAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNleftAttachment, XmATTACH_WIDGET); n++; XtSetArg (args[n], XmNleftWidget, label[1]); n++; XtSetValues (text[1], args, n); /* geometry for text 2 */ XtSetArg (args[n], XmNtopAttachment, XmATTACH_POSITION); n++; XtSetArg (args[n], XmNtopPosition, 66); n++; XtSetArg (args[n], XmNrightAttachment, XmATTACH_FORM); n++; XtSetArg (args[n], XmNleftAttachment, XmATTACH_WIDGET); n++; XtSetArg (args[n], XmNleftWidget, label[2]); n++; XtSetArg (args[n], XmNbottomAttachment, XmATTACH_FORM); n++; XtSetValues (text[2], args, n); ----------------------------------------------------------------------------- Subject: 86) TOPIC: PUSHBUTTON WIDGET ----------------------------------------------------------------------------- Subject: 87) Why can't I use accelerators on buttons not in a menu? [Last modified: Sept 94] Answer: It is apparently a difficult feature to implement, but OSF are considering this for the future. It is problematic trying to use the Xt accelerators since the Motif method interferes with this. one workaround suggested is to duplicate your non-menu button by a button in a menu somewhere, which does have a menu-accelerator installed. When the user invokes what they think is the accelerator for the button they can see Motif actually invokes the button on the menu that they can't see at the time. Another method is described below and was contributed by Harald Albrecht of Institute of Geometry and Practical Mathematics Rhine Westphalia Technical University Aachen (RWTH Aachen), Germany From albrecht@igpm.rwth-aachen.de Thu Jul 8 11:44:21 1993 NOTE: Pointers to a more recent solution by the same author follow this code sample. My work-around of this problem looks like this: (I've written that code for a Motif Object Library in C++ so please forgive me for being object orientated!) The hack consists of a rewritten message loop which checks for keypresses <MAlt>+<key>. If MessageLoop() finds such a keypress HandleAcc() ist called and the widget tree is searched for a suitable widget with the right mnemonic. // -------------------------------------------------------------------------- // traverse the widget tree starting with the given widget. // BOOL TraverseWidgetTree(Widget w, char *pMnemonic, XKeyEvent *KeyEvent) { Widget wChild; WidgetList ChildList; int NumChilds, Child; KeySym LabelMnemonic; char *pMnemonicString; // Check if the widget is a subclass of label -- then it may have an // accelerator attached... if ( XtIsSubclass(w, xmLabelWidgetClass) ) { // ok. Now: get the widget's mnemonic, convert it to ASCII and compare // it with the Key we're looking for. XtVaGetValues(w, XmNmnemonic, &LabelMnemonic, NULL); pMnemonicString = XKeysymToString(LabelMnemonic); if ( pMnemonicString && (strcasecmp(pMnemonicString, pMnemonic) == 0) ) { // stimulate the keypress XmProcessTraversal((Widget)w, XmTRAVERSE_CURRENT); KeyEvent->type = KeyPress; KeyEvent->window = XtWindow(w); KeyEvent->subwindow = XtWindow(w); KeyEvent->state = 0; KeyEvent->keycode = XKeysymToKeycode(XtDisplay(w), XK_space); XSendEvent(XtDisplay(w), XtWindow(w), True, ButtonPressMask, (XEvent*) KeyEvent); KeyEvent->type = KeyRelease; XSendEvent(XtDisplay(w), XtWindow(w), True, ButtonReleaseMask, (XEvent*) KeyEvent); return True; } } // if this widget is a subclass of Composite check all the widget's // childs. if ( XtIsSubclass(w, compositeWidgetClass) ) { // if we're in a menu (or something like that) forget this leaf of the // widget tree! if ( XtIsSubclass(w, xmRowColumnWidgetClass) ) { unsigned char RowColumnType; XtVaGetValues(w, XmNrowColumnType, &RowColumnType, NULL); if ( RowColumnType != XmWORK_AREA ) return False; } XtVaGetValues(w, XmNchildren, &ChildList, XmNnumChildren, &NumChilds, NULL); for ( Child = 0; Child < NumChilds; ++Child ) { wChild = ChildList[Child]; if ( TraverseWidgetTree(wChild, pMnemonic, KeyEvent) ) return True; } } return False; } // TraverseWidgetTree // -------------------------------------------------------------------------- // handle accelerators (keypress MAlt + key) // #define MAX_MAPPING 10 BOOL HandleAcc(Widget w, XEvent *event) { Widget widget, OldWidget; static char keybuffer[MAX_MAPPING]; int CharCount; static XComposeStatus composeStatus; // convert KeyPress to ASCII CharCount = XLookupString((XKeyEvent*) event, keybuffer, sizeof(keybuffer), NULL, &composeStatus); keybuffer[CharCount] = 0; // Only one char is alright -- then search the widget tree for a widget // with the right mnemonic if ( CharCount == 1 ) { keybuffer[0] = tolower(keybuffer[0]); widget = w; while ( (widget != NULL) && !XtIsSubclass(widget, shellWidgetClass) ) { OldWidget = widget; widget = XtParent(widget); } if ( !widget ) widget = OldWidget; return TraverseWidgetTree(widget, keybuffer, (XKeyEvent*) event); } return False; // no-one found. } // HandleAcc // -------------------------------------------------------------------------- // modified message loop // loops until the Boolean pFlag points to is set to False void MessageLoop(Boolean *pFlag) { XEvent nextEvent; while ( *pFlag ) { if ( XtAppPending(AppContext) ) { XtAppNextEvent(AppContext, &nextEvent); if ( nextEvent.type == KeyPress ) { // Falls es ein Tastendruck ist, bei dem auch noch die ALT-Taste // (=Modifier 1) gedrueckt ist, koennte es ein Accelerator sein! if ( nextEvent.xkey.state & Mod1Mask ) if ( HandleAcc(XtWindowToWidget(nextEvent.xkey.display, nextEvent.xkey.window), &nextEvent) ) continue; // Mitteilung konnte ausgeliefert werden // und darf daher nicht den ueblichen // Weg gehen! } XtDispatchEvent(&nextEvent); } } } // TApplication::MessageLoop Harald Albrecht albrecht@igpm.rwth-aachen.de Institute of Geometry and Practical Mathematics Rhine Westphalia Technical University Aachen (RWTH Aachen), Germany NOTE: Harald Albrecht has re-designed his solution so that you can assign hotkeys to *every* widget by placing a label near that widget. Get the code from: ftp.informatik.rwth-aachen.de (137.226.112.172) in: /pub/packages/Mnemonic/Mnemonic.tar.gz or from the WWW: file://134.130.161.30/arc/pub/unix/html/motifcorner.html ----------------------------------------------------------------------------- Subject: 88) TOPIC: ICON WIDGET ----------------------------------------------------------------------------- Subject: 89) How can I add multi-colored icons to my application? [Last modified: Sept 94] Answer: Get the Xpm (X PixMap file format) widgets. There is a tutorial in the directory ftp.x.org:/contrib/docs/xpm_tut and source code in the directory ftp.x.org:/contrib/libraries. Documentation is part of the tar file found in /contrib/libraries. The /contrib/libraries directory also contains xpm.FAQ. There is also a mailing list: xpm-talk@sophia.inria.fr. ----------------------------------------------------------------------------- Subject: 90)+ How can I convert a Sun/GIF/TIFF image to a pixmap? [Last modified: Oct 94] Answer: An application called "xv" (interactive image display for the X Window System) is useful for displaying and converting many image formats. From the man page: xv is an X11 program that displays images in the GIF, JPEG, TIFF, PBM, PGM, PPM, X11 bitmap, PDS/VICAR, Sun Rasterfile, and PM formats on 1-, 2-, 4-, 6-, 8-, 16-, 24-, and 32-bit X displays. xv will also read compress-ed versions of these files. You can get "xv" (shareware by John Bradley et al) from: ftp://ftp.cis.upenn.edu/pub/xv or: ftp://ftp.x.org/R5contrib/xv-3.01.tar.gz Another useful conversion package is "pbm" (portable bitmap file format) by Jef Poskanzer et al, available from: ftp://ftp.x.org/R5contrib/netpbm-1mar1994.tar.gz or: ftp://ftp.x.org/R5contrib/pbmplus10dec91.tar.Z (much older :-) You might also want to check the X11 FAQ for additional conversion options: ftp://ftp.x.org/contrib/faqs/FAQ ----------------------------------------------------------------------------- Subject: 91) TOPIC: LABEL WIDGET ----------------------------------------------------------------------------- Subject: 92) How can I align the text in a label (button, etc) widget? Answer: The alignment for the label widget is controlled by the resource XmNalignment, and the default centers the text. Use this resource to change it to left or right alignment. However, when the label (or any descendant) is in a row column, and XmNisAligned is True (the default), the row column aligns text using its resource XmNentryAlignment. If you want simultaneous control over all widgets use this, but otherwise turn XmNisAligned off and do it individually. ----------------------------------------------------------------------------- Subject: 93) Why doesn't label alignment work in a RowColumn? Answer: RowColumn has a resource XmNisAligned (default True) and and XmNentryAlignment (default XmALIGNMENT_BEGINNING). These control alignment of the labelString in Labels and descendants. Set XmNisAligned to False to turn this off. ----------------------------------------------------------------------------- Subject: 94) How can I set a multiline label? [Last modified: September 92] Answer: In .Xdefaults *XmLabel*labelString: Here\nis\nthe\nLabel This method does not seem to work in some of the older Motif 1.0 versions. In code, char buf[128]; XmString msg; sprintf(buf, "Here\nis\nthe\nLabel"); msg = XmStringCreateLtoR(buf, XmSTRING_DEFAULT_CHARSET); XtSetArg (args[n], XmNlabelString, msg); Gives a four line label, using the escape sequence \n for a newline. However, XmStringCreateLtoR() is obsoleted from version 1.1 on, and may disappear. This is because it it is only in the AES as "trial-use" and has been proposed for removal from the AES. Realistically, it will probably not be removed from any backward compatible versions of Motif, but the potential is there. If it does disappear (or if you want to avoid using the non-AES compliant XmSTRING_DEFAULT_CHARSET), try this from Jean-Philippe Martin-Flatin <syj@ecmwf.co.uk> #include <Xm/Xm.h> #include <string.h> /*----------------------------------------------------- Create a new XmString from a char* This function can deal with embedded 'newline' and is equivalent to the obsolete XmStringCreateLtoR, except it does not use non AES compliant charset XmSTRING_DEFAULT_CHARSET ----------------------------------------------------*/ XmString xec_NewString(char *s) { XmString xms1; XmString xms2; XmString line; XmString separator; char *p; char *t = XtNewString(s); /* Make a copy for strtok not to */ /* damage the original string */ separator = XmStringSeparatorCreate(); p = strtok(t,"\n"); xms1 = XmStringCreateSimple(p); while (p = strtok(NULL,"\n")) { line = XmStringCreateSimple(p); xms2 = XmStringConcat(xms1,separator); XmStringFree(xms1); xms1 = XmStringConcat(xms2,line); XmStringFree(xms2); XmStringFree(line); } XmStringFree(separator); XtFree(t); return xms1; } Do not use XmStringCreateSimple() - it does not process the newline character in the way you want. ----------------------------------------------------------------------------- Subject: 95) How can I have a vertical label? Answer: Make a multiline label with one character per line, as in the last question. There is no way to make the text rotated by 90 degrees though. ----------------------------------------------------------------------------- Subject: 96) How can I have a Pixmap in a Label? Answer: From Bob Hays (bobhays@spss.com) Pixmap px_disarm, px_disarm_insens; Widget Label1; Pixel foreground, background; Arg args[4]; Arg arg[] = { { XmNforeground, &foreground }, { XmNbackground, &background } }; Label1 = XmCreateLabel ( Shell1, "Label1", (Arg *) NULL, (Cardinal) 0 ); XtGetValues ( Label1, arg, XtNumber ( arg ) ); px_disarm = XCreatePixmapFromBitmapData(display, DefaultRootWindow(display), mtn_bits, mtn_width, mtn_height, foreground, background, DefaultDepth(display,DefaultScreen(display))); px_disarm_insens = XCreatePixmapFromBitmapData(display, DefaultRootWindow(display), mtn_ins_bits, mtn_ins_width, mtn_ins_height, foreground, background, DefaultDepth(display,DefaultScreen(display))); n = 0; XtSetArg(args[n], XmNlabelType, XmPIXMAP); n++; XtSetArg(args[n], XmNlabelPixmap, px_disarm); n++; XtSetArg(args[n], XmNlabelInsensitivePixmap, px_disarm_insens ); n++; XtSetValues ( Label1, args, n ); XtManageChild(Label1); That will cause the foreground and background of your pixmap to be inherited from the one that would be used by OSF/Motif when the label is displayed. The advantage is that this will utilize any resource values the user may have requested without looking explicitly into the resource database. And, you will have a pixmap handy if the application insensitizes the label (without an XmNlabelInsensitivePixmap your label will go empty if made insensitive). [Bob's original code was for a PushButton. Just change all Label to PushButton for them.] ----------------------------------------------------------------------------- Subject: 97) TOPIC: DRAWING AREA WIDGET ----------------------------------------------------------------------------- Subject: 98) How can I send an expose event to a Drawing Area widget? (or any other, come to that). I want to send an expose event so that it will redraw itself. Answer: Use the Xlib call XClearArea(XtDisplay(w), XtWindow(w), 0, 0, 0, 0, True) This clears the widget's window and generates an expose event in doing so. The widgets expose action will then redraw it. This uses a round trip request. An alternative, without the round trip is from orca!mesa!rthomson@uunet.uu.net (Rich Thomson): Widget da; XmDrawingAreaCallbackStruct da_struct; da_struct.reason = XmCR_EXPOSE; da_struct.event = (XEvent *) NULL; da_struct.window = XtWindow(da); XtCallCallbacks(da, XmNexposeCallback, (XtPointer) da_struct); ----------------------------------------------------------------------------- Subject: 99) How can I know when a DrawingArea has been resized? It generates an expose event whn it is enlarged, but not when it is shrunk. Answer: Use the resize callback. ----------------------------------------------------------------------------- Subject: 100) TOPIC: MENUS ----------------------------------------------------------------------------- Subject: 101) How do I set the current choice in a radio box or an option menu? [Last modified: Sept 94] Answer: Set the XmNmenuHistory resource on its RowColumn parent. Thanks to Ken Lee, kenton@esd.sgi.com ----------------------------------------------------------------------------- Subject: 102) How do I make a menu choice insensitive if it was created with XmVaCreateSimplePulldownMenu? [Last modified: Sept 94] Answer: According to the Motif manual, the buttons are named "button_n", where "n" is an integer starting from 0. You can use XtNameToWidget() to convert these names to widget ID's. Thanks to Ken Lee, kenton@esd.sgi.com ----------------------------------------------------------------------------- Subject: 103) What can I put inside a menu bar? Answer: You can only put cascade buttons in menu bars. No pushbuttons, toggle buttons or gadgets are allowed. When you create a pulldown menu with parent a menu bar, its real parent is a shell widget. ----------------------------------------------------------------------------- Subject: 104) Can I have a cascade button without a submenu in a pulldown menu? Answer: Yes you can. A cascade button has an activate callback which is called when you click on it and it doesn't have a submenu. It can have a mnemonic, but keyboard traversal using the arrow keys in the menu will skip over it. ----------------------------------------------------------------------------- Subject: 105) Should I have a cascade button without a submenu in a pulldown menu? Answer: No. This is forbidden by the style guide. Technically you can do it (see previous question) but if you do it will not be Motif style compliant. This is unlikely to change - if a "button" is important enough to be in a pulldown menu bar with no pulldown, it should be a button elsewhere. (Mind you, you won't be able to put accelerators on it elsewhere though.) ----------------------------------------------------------------------------- Subject: 106) What is the best way to create popup menus? [Last modified: August 92] Susan Murdock Thompson (from OSF): In general, create a popupMenu as the child from which you will be posting it from (ie: if you have a bulletinBoard with a PushButton in it and want MB2 on the pushButton to post the popupMenu, create the popupMenu as a child of the pushButton). [This parent-child relationship seems to make a big difference in the behavior of the popups.] Add an event handler to handle buttonPress events. You'll need to check for the correct button (what you've specified menuPost to be) before posting the menu. To create a popup that can be accessible from within an entire client window, create it as the child of the top-most widget (but not the shell) and add event handlers for the top-most widget and children widgets. ie: { .... XtManageChild(rc=XmCreateRowColumn(Shell1, "rc", NULL, 0)); XtManageChild(label = XmCreateLabel(rc, "label", NULL, 0)); XtManageChild(text = XmCreateText(rc, "text", NULL, 0)); XtManageChild(pushbutton = XmCreatePushButton(rc, "pushbutton", NULL, 0)); n = 0; XtSetArg(args[n], XmNmenuPost, "<Btn3Down>"); n++; popup = XmCreatePopupMenu(rc, "popup", args, n); XtAddEventHandler(rc, ButtonPressMask, False, PostMenu3, popup); XtAddEventHandler(text, ButtonPressMask, False, PostMenu3, popup); XtAddEventHandler(label, ButtonPressMask, False, PostMenu3, popup); XtAddEventHandler(pushbutton, ButtonPressMask, False, PostMenu3, popup); XtManageChild(m1 = XmCreatePushButton(popup, "m1", NULL, 0)); XtManageChild(m2 = XmCreatePushButton(popup, "m2", NULL, 0)); XtManageChild(m3 = XmCreatePushButton(popup, "m3", NULL, 0)); XtAddCallback(m1, XmNactivateCallback, SayCB, "button M1"); XtAddCallback(m2, XmNactivateCallback, SayCB, "button M2"); XtAddCallback(m3, XmNactivateCallback, SayCB, "button M3"); ... } /* where PostMenu3 is ... */ PostMenu3 (w, popup, event) Widget w; Widget popup; XButtonEvent * event; { printf("menuPost = 3, button %d0, event->button); if (event->button != Button3) return; XmMenuPosition(popup, event); XtManageChild(popup); } ----------------------------------------------------------------------------- END OF PART THREE