;/* simplegtgadget.c -- execute me to compile me
lc -b1 -cfistq -v -y simplegtgadget
blink FROM LIB:c.o simplegtgadget.o TO simplegtgadget LIB LIB:lc.lib LIB:amiga.lib
quit
**
** The example listed here shows how to use the NewGadget structure and
** the GadTools library functions discussed above to create a simple
** button gadget.
**
** Simple example of a GadTools gadget.  Compiled with SAS C v5.10a
*/
#define INTUI_V36_NAMES_ONLY

#include <exec/types.h>
#include <intuition/intuition.h>
#include <intuition/gadgetclass.h>
#include <libraries/gadtools.h>

#include <clib/exec_protos.h>
#include <clib/intuition_protos.h>
#include <clib/gadtools_protos.h>

#include <stdio.h>

#ifdef LATTICE
int CXBRK(void)    { return(0); }  /* Disable Lattice CTRL/C handling */
int chkabort(void) { return(0); }  /* really */
#endif

/* Gadget defines of our choosing, to be used as GadgetID's. */
#define MYGAD_BUTTON    (4)

VOID process_window_events(struct Window *);
VOID gadtoolsWindow(VOID);

struct TextAttr Topaz80 = { "topaz.font", 8, 0, 0, };

struct Library *IntuitionBase;
struct Library *GadToolsBase;


/*
** Open all libraries and run.  Clean up when finished or on error..
*/
void main(void)
{
if ( (IntuitionBase = OpenLibrary("intuition.library", 37)) != NULL )
    {
    if ( (GadToolsBase = OpenLibrary("gadtools.library", 37)) != NULL )
        {
        gadtoolsWindow();

        CloseLibrary(GadToolsBase);
        }
    CloseLibrary(IntuitionBase);
    }
}


/*
** Prepare for using GadTools, set up gadgets and open window.
** Clean up and when done or on error.
*/
VOID gadtoolsWindow(VOID)
{
struct Screen    *mysc;
struct Window    *mywin;
struct Gadget    *glist, *gad;
struct NewGadget ng;
void             *vi;

glist = NULL;

if ( (mysc = LockPubScreen(NULL)) != NULL )
    {
    if ( (vi = GetVisualInfo(mysc, TAG_END)) != NULL )
        {
        /* GadTools gadgets require this step to be taken */
        gad = CreateContext(&glist);

        /* create a button gadget centered below the window title */
        ng.ng_TextAttr   = &Topaz80;
        ng.ng_VisualInfo = vi;
        ng.ng_LeftEdge   = 150;
        ng.ng_TopEdge    = 20 + mysc->WBorTop + (mysc->Font->ta_YSize + 1);
        ng.ng_Width      = 100;
        ng.ng_Height     = 12;
        ng.ng_GadgetText = "Click Here";
        ng.ng_GadgetID   = MYGAD_BUTTON;
        ng.ng_Flags      = 0;
        gad = CreateGadget(BUTTON_KIND, gad, &ng, TAG_END);

        if (gad != NULL)
            {
            if ( (mywin = OpenWindowTags(NULL,
                    WA_Title,     "GadTools Gadget Demo",
                    WA_Gadgets,   glist,      WA_AutoAdjust,    TRUE,
                    WA_Width,       400,      WA_InnerHeight,    100,
                    WA_DragBar,    TRUE,      WA_DepthGadget,   TRUE,
                    WA_Activate,   TRUE,      WA_CloseGadget,   TRUE,
                    WA_IDCMP, IDCMP_CLOSEWINDOW |
                              IDCMP_REFRESHWINDOW | BUTTONIDCMP,
                    WA_PubScreen,   mysc,
                    TAG_END)) != NULL )
                {
                GT_RefreshWindow(mywin, NULL);

                process_window_events(mywin);

                CloseWindow(mywin);
                }
            }
        /* FreeGadgets() must be called after the context has been
        ** created.  It does nothing if glist is NULL
        */
        FreeGadgets(glist);
        FreeVisualInfo(vi);
        }
    UnlockPubScreen(NULL, mysc);
    }
}

/*
** Standard message handling loop with GadTools message handling functions
** used (GT_GetIMsg() and GT_ReplyIMsg()).
*/
VOID process_window_events(struct Window *mywin)
{
struct IntuiMessage *imsg;
struct Gadget *gad;
BOOL  terminated = FALSE;

while (!terminated)
    {
    Wait (1 << mywin->UserPort->mp_SigBit);

    /* Use GT_GetIMsg() and GT_ReplyIMsg() for handling */
    /* IntuiMessages with GadTools gadgets.             */
    while ((!terminated) && (imsg = GT_GetIMsg(mywin->UserPort)))
        {
        /* GT_ReplyIMsg() at end of loop */

        switch (imsg->Class)
            {
            case IDCMP_GADGETUP:       /* Buttons only report GADGETUP */
                gad = (struct Gadget *)imsg->IAddress;
                if (gad->GadgetID == MYGAD_BUTTON)
                        printf("Button was pressed.\n");
                break;
            case IDCMP_CLOSEWINDOW:
                terminated = TRUE;
                break;
            case IDCMP_REFRESHWINDOW:
                /* This handling is REQUIRED with GadTools. */
                GT_BeginRefresh(mywin);
                GT_EndRefresh(mywin, TRUE);
                break;
            }
        /* Use the toolkit message-replying function here... */
        GT_ReplyIMsg(imsg);
        }
    }
}

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