Conference bulova::decw_jan-89_to_nov-90

392.0. "Bunch of toolkit/UIL questions" by 32291::FRANCUS (Mets in '89) Mon Mar 13 1989 11:38

    A bunch of questions, some easy some a bit more difficult.
    
    Starting from the easy:
    
    0) Where can I find documentation/examples for User Defined widgets?
    
    1) The documentation on the clipboard for DwtBeginCopyToClipboard
    talks about the label parameter. In it it mentions something called
    a clipboard viewer, what is a clipboard viewer?? Is it simply a
    user application that sees whats in the clipboard or something else?
    
    2) Is there any way to get a dialog box to do geometry management.
    That is if it has a child, and the child has graphics in it, and
    the dialog box is resized then the child with its graphics are resized
    to be scaled with the new size of the dialog box?
    
    3) Can one size the scroll bar for a main window. The main window
    has a very definite idea what the size of its scroll bar should
    be, can an application override this easily with some use of XtSetArgs,
    XtSetValues, or using UIL? Maybe using DwtMainSetAreas in some way?
    Any ideas??
    
    4) When in a text widget a user highlights part of a line. The user
    now changes the insertion point to another portion of the text. If this
    happens the programmer wants to unhighlight the highlighted text.
    Unhighlighting text is easy. The problem is there doesn't seem to
    be a reason for a Text Widget that is set when the user moves the
    input focus to another part of a dialog box. Am I missing something
    really trivial??
    
    5) When a user logs into a session they type in their login name
    and if they hit CR the cursor is moved to the next Text Widget (the
    password prompt), not to the next line. How can one map the crlf
    to go to the next text widget. I seem to recall using some kind
    of translation event as a possibility.
                                                   
    6) A push button widget has a callback that loads in a UIL hierarchy.
    If the top widget it loads in is a pop-up dialog box, then one sees
    the whole dialog box. However, if the top widget in the UIL file
    is a main_window widget it gets clipped by the main_window of which
    the push_button widget is a child?? Did we make a pop-up dialog
    box a shell widget, similar to pull down menus, so it breaks out
    of its parent window?? Or is there something strange about the
    main_window widget?
               
    7) Using UIL is there any way to specify radio buttons AND toggle
    buttons in the same pulldown menu. A pull down menu has an attribute
    menu_radio which can be set to TRUE for radio buttons, FALSE if
    one wants standard toggle buttons. A pulldown_menu in UIL cannot
    have a radio box widget as a child. There doesn't seem to be any
    way to mix toggle buttons adn radio buttons using UIL. Any ideas??
    
    The next few questions remind me of some FT2 problems, so I'm holding
    off until SDC gets loaded onto the development machine, but anyway:
    
    8) LoadQueryFont seems to be problematic if used in conjunction
    with XUI toolkit.  It gives a typically non-helpful Xlib error message.
    More info on the message is hopefully forthcoming.
     
    9) A main_window widget core dumps when a child of it is a user
    defined widget. All widgets are defined in UIL.
    
    10)A text widget with a menu bar. When a pull_down menu is used,
    overlays text, then the text is reexposed it appears to be off by
    one pixel.    
    
    Thanks for all and any help.
    
    yoseff
    

>    0) Where can I find documentation/examples for User Defined
>    widgets?
    
    There isn't much. The MIT Xtoolkit Intrinsics manual is the best
    source of (mostly reference) information, other than widget sources.
    The DECwindows Application Programmer's Guide has an appendix that
    (inadequately) discusses widget writing, mostly by massaging
    excerpts from the MIT Intrinsics manual. However there are several
    good widget examples in the ELKTRA::DW_EXAMPLES notes file.
    
>   2) Is there any way to get a dialog box to do geometry management.
>   That is if it has a child, and the child has graphics in it, and
>   the dialog box is resized then the child with its graphics are resized
>   to be scaled with the new size of the dialog box?
    
    Using an attached dialog box, you can get the child resized by
    "attaching" its edges to the edges of its parent, but there's no
    automatic scaling of the contents of the child.
        
>   5) When a user logs into a session they type in their login name
>   and if they hit CR the cursor is moved to the next Text Widget (the
>   password prompt), not to the next line. How can one map the crlf
>   to go to the next text widget. I seem to recall using some kind
>   of translation event as a possibility.
   
    The translation:
      
        "<Key>0xFF0D: return_pressed()"

    Then write the action routine to correspond to "return_pressed",
    that calls XtCallAcceptFocus() for the widget that should get
    the focus next, and reference it in an Action table. See XtAddActions.
                                                 

>>   5) When a user logs into a session they type in their login name
>>   and if they hit CR the cursor is moved to the next Text Widget (the
>>   password prompt), not to the next line. How can one map the crlf
>>   to go to the next text widget. I seem to recall using some kind
>>   of translation event as a possibility.
   
>    The translation:
>      
>        "<Key>0xFF0D: return_pressed()"
>
>    Then write the action routine to correspond to "return_pressed",
>    that calls XtCallAcceptFocus() for the widget that should get
>    the focus next, and reference it in an Action table. See XtAddActions.
   
  RE: .1 Could you elaborate on this process.  I would be very interested in
       having a simple text widget, and upon pressing return, instead of another
       line being created in the widget, the focus go to a button.

       For example many applications use this, press return after simple text
       and the OK button will be activated.

Could you elaborate?

		$$$$ ted $$$$

    Extracted from one of my demos:
    
    static XtActionProc TransferFocus();
    char *cr_bindings = "<Key>0xFF0D: transfer-focus()";
    static XtActionsRec cr_actions[] = {
       {"transfer-focus", TransferFocus}
    }
    
    ...
    
    XtAddActions(cr_actions,1);
    XtOverrideTranslations(source_widget,
                           XtParseTranslationTable(cr_bindings));
    
    ...
    
    static XtActionProc TransferFocus(widget,event,params,nparams)
       Widget widget;
       XEvent *event;
       char **params;
       int *nparams;
    {
       Time time = CurrentTime;
    
       XtCallAcceptFocus(target_widget,&time);
    }
    
    Happy programming,
    Dave