wmaker/WINGs/mywidget.c

/*
 * Demo user widget for WINGs
 *
 * Author: Alfredo K. Kojima
 * 
 * This file is in the public domain.
 * 
 */


/*
 *
 * Include the WINGs private data header.
 *
 * 
 */
#include "WINGsP.h"

/*
 * Our public header.
 */
#include "mywidget.h"

/*
 * Define the widget "class"
 */
typedef struct W_MyWidget {
    /* these two fields must be present in all your widgets in this 
     * exact position */
    W_Class widgetClass;
    WMView *view;
    
    /* put your stuff here */
    char *text;
    
} _MyWidget;




/* some forward declarations */

static void destroyMyWidget(_MyWidget *mPtr);
static void paintMyWidget(_MyWidget *mPtr);


static void handleEvents(XEvent *event, void *data);
static void handleActionEvents(XEvent *event, void *data);



/*
 * Delegates 
 * See the source for the other widgets to see how to use.
 * You won't need to use this most of the time.
 */
static W_ViewDelegate _MyWidgetDelegate = {
	NULL,
	NULL,
	NULL,
	NULL,
	NULL
};


/* our widget class ID */
static W_Class myWidgetClass = 0;


/*
 * Initializer for our widget. Must be called before creating any
 * instances of the widget.
 */
W_Class
InitMyWidget(WMScreen *scr)
{
    /* register our widget with WINGs and get our widget class ID */
    if (!myWidgetClass) {
	myWidgetClass = W_RegisterUserWidget();
    }
    
    return myWidgetClass;
}


/*
 * Our widget fabrication plant.
 */
MyWidget*
CreateMyWidget(WMWidget *parent)
{
    MyWidget *mPtr;
    
    /* allocate some storage for our new widget instance */
    mPtr = wmalloc(sizeof(MyWidget));
    /* initialize it */
    memset(mPtr, 0, sizeof(MyWidget));

    /* set the class ID */
    mPtr->widgetClass = myWidgetClass;

    /* 
     * Create the view for our widget.
     * Note: the Window for the view is only created after the view is
     * realized with W_RealizeView()
     * 
     * Consider the returned view as read-only.
     */
    mPtr->view = W_CreateView(W_VIEW(parent));
    if (!mPtr->view) {
	wfree(mPtr);
	return NULL;
    }
    /* always do this */
    mPtr->view->self = mPtr;

    /* setup the delegates for the view */
    mPtr->view->delegate = &_MyWidgetDelegate;

    /*
     * Intercept some events for our widget, so that we can handle them.
     */
    WMCreateEventHandler(mPtr->view, ExposureMask /* this allows us to know when we should paint */
			 |StructureNotifyMask, /* this allows us to know things like when we are destroyed */
			 handleEvents, mPtr);

    /*
     * Intercept some other events. This could be merged with the above
     * call, but we separate for more organization.
     */
    WMCreateEventHandler(mPtr->view, ButtonPressMask,handleActionEvents, mPtr);

    return mPtr;
}



/*
 * Paint our widget contents.
 */
static void
paintMyWidget(_MyWidget *mPtr)
{
    W_Screen *scr = mPtr->view->screen;
    WMColor *color;


    if (mPtr->text) {
	
	color = WMWhiteColor(scr);
	
	W_PaintText(mPtr->view, mPtr->view->window, scr->normalFont,  0, 0,
		    mPtr->view->size.width, WACenter, WMColorGC(color),
		    False, mPtr->text, strlen(mPtr->text));
	
	WMReleaseColor(color);
    }
}



static void
handleEvents(XEvent *event, void *data)
{
    _MyWidget *mPtr = (_MyWidget*)data;


    switch (event->type) {	
     case Expose:
	if (event->xexpose.count!=0)
	    break;
	paintMyWidget(mPtr);
	break;
	
     case DestroyNotify:
	destroyMyWidget(mPtr);
	break;
	
    }
}


static void
handleActionEvents(XEvent *event, void *data)
{
    _MyWidget *mPtr = (_MyWidget*)data;

    switch (event->type) {
     case ButtonPress:
	XBell(mPtr->view->screen->display, 100);
	XBell(mPtr->view->screen->display, 100);
	break;
    }
}


void
SetMyWidgetText(MyWidget *mPtr, char *text)
{
    CHECK_CLASS(mPtr, myWidgetClass);

    if (mPtr->text)
	wfree(mPtr->text);
    
    mPtr->text = wstrdup(text);
    
    if (W_VIEW_MAPPED(mPtr->view)) {
	paintMyWidget(mPtr);
    }
}



static void
destroyMyWidget(_MyWidget *mPtr)
{
    /*
     * Free all data we allocated for our widget. 
     */
        
    if (mPtr->text)
	wfree(mPtr->text);
    
    wfree(mPtr);
}