WINGs/Tests/mywidget.c

   1 /*
   2  * Demo user widget for WINGs
   3  *
   4  * Author: Alfredo K. Kojima
   5  *
   6  * This file is in the public domain.
   7  *
   8  */
   9
  10 /*
  11  *
  12  * Include the WINGs private data header.
  13  *
  14  *
  15  */
  16 #include <WINGs/WINGsP.h>
  17
  18 /*
  19  * Our public header.
  20  */
  21 #include "mywidget.h"
  22
  23 /*
  24  * Define the widget "class"
  25  */
  26 typedef struct W_MyWidget {
  27         /* these two fields must be present in all your widgets in this
  28          * exact position */
  29         W_Class widgetClass;
  30         WMView *view;
  31
  32         /* put your stuff here */
  33         char *text;
  34
  35 } _MyWidget;
  36
  37 /* some forward declarations */
  38
  39 static void destroyMyWidget(_MyWidget * mPtr);
  40 static void paintMyWidget(_MyWidget * mPtr);
  41
  42 static void handleEvents(XEvent * event, void *data);
  43 static void handleActionEvents(XEvent * event, void *data);
  44
  45 /*
  46  * Delegates
  47  * See the source for the other widgets to see how to use.
  48  * You won't need to use this most of the time.
  49  */
  50 static W_ViewDelegate _MyWidgetDelegate = {
  51         NULL,
  52         NULL,
  53         NULL,
  54         NULL,
  55         NULL
  56 };
  57
  58 /* our widget class ID */
  59 static W_Class myWidgetClass = 0;
  60
  61 /*
  62  * Initializer for our widget. Must be called before creating any
  63  * instances of the widget.
  64  */
  65 W_Class InitMyWidget(WMScreen * scr)
  66 {
  67         /* register our widget with WINGs and get our widget class ID */
  68         if (!myWidgetClass) {
  69                 myWidgetClass = W_RegisterUserWidget();
  70         }
  71
  72         return myWidgetClass;
  73 }
  74
  75 /*
  76  * Our widget fabrication plant.
  77  */
  78 MyWidget *CreateMyWidget(WMWidget * parent)
  79 {
  80         MyWidget *mPtr;
  81
  82         /* allocate some storage for our new widget instance */
  83         mPtr = wmalloc(sizeof(MyWidget));
  84         /* initialize it */
  85         memset(mPtr, 0, sizeof(MyWidget));
  86
  87         /* set the class ID */
  88         mPtr->widgetClass = myWidgetClass;
  89
  90         /*
  91          * Create the view for our widget.
  92          * Note: the Window for the view is only created after the view is
  93          * realized with W_RealizeView()
  94          *
  95          * Consider the returned view as read-only.
  96          */
  97         mPtr->view = W_CreateView(W_VIEW(parent));
  98         if (!mPtr->view) {
  99                 wfree(mPtr);
 100                 return NULL;
 101         }
 102         /* always do this */
 103         mPtr->view->self = mPtr;
 104
 105         /* setup the delegates for the view */
 106         mPtr->view->delegate = &_MyWidgetDelegate;
 107
 108         /*
 109          * Intercept some events for our widget, so that we can handle them.
 110          */
 111         WMCreateEventHandler(mPtr->view, ExposureMask   /* this allows us to know when we should paint */
 112                              | StructureNotifyMask,     /* this allows us to know things like when we are destroyed */
 113                              handleEvents, mPtr);
 114
 115         /*
 116          * Intercept some other events. This could be merged with the above
 117          * call, but we separate for more organization.
 118          */
 119         WMCreateEventHandler(mPtr->view, ButtonPressMask, handleActionEvents, mPtr);
 120
 121         return mPtr;
 122 }
 123
 124 /*
 125  * Paint our widget contents.
 126  */
 127 static void paintMyWidget(_MyWidget * mPtr)
 128 {
 129         W_Screen *scr = mPtr->view->screen;
 130         WMColor *color;
 131
 132         if (mPtr->text) {
 133
 134                 color = WMWhiteColor(scr);
 135
 136                 W_PaintText(mPtr->view, mPtr->view->window, scr->normalFont, 0, 0,
 137                             mPtr->view->size.width, WACenter, color, False, mPtr->text, strlen(mPtr->text));
 138
 139                 WMReleaseColor(color);
 140         }
 141 }
 142
 143 static void handleEvents(XEvent * event, void *data)
 144 {
 145         _MyWidget *mPtr = (_MyWidget *) data;
 146
 147         switch (event->type) {
 148         case Expose:
 149                 if (event->xexpose.count != 0)
 150                         break;
 151                 paintMyWidget(mPtr);
 152                 break;
 153
 154         case DestroyNotify:
 155                 destroyMyWidget(mPtr);
 156                 break;
 157
 158         }
 159 }
 160
 161 static void handleActionEvents(XEvent * event, void *data)
 162 {
 163         _MyWidget *mPtr = (_MyWidget *) data;
 164
 165         switch (event->type) {
 166         case ButtonPress:
 167                 XBell(mPtr->view->screen->display, 100);
 168                 XBell(mPtr->view->screen->display, 100);
 169                 break;
 170         }
 171 }
 172
 173 void SetMyWidgetText(MyWidget * mPtr, char *text)
 174 {
 175         CHECK_CLASS(mPtr, myWidgetClass);
 176
 177         if (mPtr->text)
 178                 wfree(mPtr->text);
 179
 180         mPtr->text = wstrdup(text);
 181
 182         if (W_VIEW_MAPPED(mPtr->view)) {
 183                 paintMyWidget(mPtr);
 184         }
 185 }
 186
 187 static void destroyMyWidget(_MyWidget * mPtr)
 188 {
 189         /*
 190          * Free all data we allocated for our widget.
 191          */
 192
 193         if (mPtr->text)
 194                 wfree(mPtr->text);
 195
 196         wfree(mPtr);
 197 }