Boopsi Button and Progress Class 37.3

                           February 6, 1994

                      Written by Douglas Keller


0.  Introduction
----------------

Buttonclass is a boopsi custom gadget which looks like a standard
gadtools button gadget.  The buttonclass supports a couple of things
gadtools does not, the foreground and background color of the gadget
can be changed, and the gadget can be put into the selected state so
the gadget looks depressed.

Starting with 37.3 the button class supports a standard drawer image
to signal it will open a file requester if pressed.

Also starting with 37.3 a progress indicator gadget is included, it is
used to show the progress of an operation from 0 to 100 percent.

ButtonClass is based on the example in the RKM Libraries manual.


1.  Files
---------

buttonclass.h    - public include file for buttonclass and progressclass

buttonclass.c    - Sas/C 6.51 code for the buttonclass

progressclass.c  - Sas/C 6.51 code for the progressclass

ButtonClassNB.lib- scanned library containing the classes

lmkfile          - Sas/C 6.51 makefile

test             - test program that uses the classes

test.c           - source to test program

headers.h        - system headers for buttonclass.c and progressclass.c


2.  Using the ButtonClass
-------------------------

The buttonclass includes a set of functions to initialize and free the
buttonclass.

    Class *initButtonGadgetClass ( struct Library *IntuitionBase,
               struct Library *UtilityBase, struct Library *GfxBase );

    BOOL freeButtonGadgetClass ( Class *cl );

InitButtonGadgetClass() takes IntuitionBase, UtilityBase, and GfxBase
as arguments.  The reason they are passed in rather then global is so
the buttonclass can be used in a reentrant program which has no
writable global data.

To use the progress class, initProgressGadgetClass() and
freeProgressGadgetClass() needs to be used.

The Class returned by initButtonGadgetClass() is then passed to
NewObject() to create the gadget.

    gad = NewObject(buttonClass, NULL,
        GA_ID,          1L,
        GA_Top,         20
        GA_Left,        20,
        GA_Width,       100,
        GA_Height,      11,
        GA_Immediate,   TRUE,
        GA_RelVerify,   TRUE,
        BUT_Text,       "Label",
        TAG_DONE);

SetGadgetAttrs() can be used to change gadget attributes.

    SetGadgetAttrs(gad, window, NULL,  /* make the gadget selected */
        GA_Selected,    TRUE,
        TAG_DONE);

    SetGadgetAttrs(gad, window, NULL,  /* change gadget text */
        BUT_Text,       "new text",
        TAG_DONE);

Buttonclass supports the following gadgets.

    BUT_Text       - STRPTR used for the text of the gadget.
    BUT_Color      - Foreground (text) color of the gadget.
    BUT_Key        - char which should be underlined if found in BUT_Text.
    BUT_BackColor  - Background color of the gadget.
    BUT_TextFont   - TextFont struct to used for BUT_Text.

    New of 37.2

    BUT_Image      - Image to display in the unselected state, (struct Image *)
    BUT_SelectImage- Image to display in the selected state, (struct Image *)
    GA_Disabled    - Disabled TRUE or FALSE.

    New of 37.3

    BUT_Drawer     - BOOL, if TRUE show a standard drawer image in
                     button.
    PRO_Min        - The low value of the progress indicator, defaults to 0.
    PRO_Max        - The high value of the progress indicator, defaults to 100.
    PRO_Current    - The current value of the progress indicator, must
                     between PRO_Min and PRO_Max.
    PRO_ShowPercent- BOOL, if TRUE show percentage in indicator bar.
    PRO_TextFont   - TextFont struct to used for PRO_ShowPercent.


Currently the Images are drawn relative to the top left corner of
the gadget using the TopEdge and LeftEdge of Image.  When I get some
time I am going to add support for different justifications of the
Images and Text.

If only a BUT_Image is given, the image is draw in the selected state
when it is selected.  This allows boopsi images to be drawn in the
selected state.


3.  Legal junk
--------------

Permission is granted to distribute this program and its documentation
for non-commercial purposes.  This program may not be distributed for
a profit without permission from Doug Keller.  Fred Fish has
permission to distribute this program as part of the Fred Fish
library.

This code can be used for any purpose as long as credit is given.


4.  Bugs and Info
-----------------

If you would like to get in touch with me I can be reached on the
following:

            Bix : dkeller
        Internet: dkeller@vnet.ibm.com