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         (void)scr;
  68         /* register our widget with WINGs and get our widget class ID */
  69         if (!myWidgetClass) {
  70                 myWidgetClass = W_RegisterUserWidget();
  71         }
  72
  73         return myWidgetClass;
  74 }
  75
  76 /*
  77  * Our widget fabrication plant.
  78  */
  79 MyWidget *CreateMyWidget(WMWidget * parent)
  80 {
  81         MyWidget *mPtr;
  82
  83         /* allocate some storage for our new widget instance */
  84         mPtr = wmalloc(sizeof(MyWidget));
  85         /* initialize it */
  86         memset(mPtr, 0, sizeof(MyWidget));
  87
  88         /* set the class ID */
  89         mPtr->widgetClass = myWidgetClass;
  90
  91         /*
  92          * Create the view for our widget.
  93          * Note: the Window for the view is only created after the view is
  94          * realized with W_RealizeView()
  95          *
  96          * Consider the returned view as read-only.
  97          */
  98         mPtr->view = W_CreateView(W_VIEW(parent));
  99         if (!mPtr->view) {
 100                 wfree(mPtr);
 101                 return NULL;
 102         }
 103         /* always do this */
 104         mPtr->view->self = mPtr;
 105
 106         /* setup the delegates for the view */
 107         mPtr->view->delegate = &_MyWidgetDelegate;
 108
 109         /*
 110          * Intercept some events for our widget, so that we can handle them.
 111          */
 112         WMCreateEventHandler(mPtr->view, ExposureMask   /* this allows us to know when we should paint */
 113                              | StructureNotifyMask,     /* this allows us to know things like when we are destroyed */
 114                              handleEvents, mPtr);
 115
 116         /*
 117          * Intercept some other events. This could be merged with the above
 118          * call, but we separate for more organization.
 119          */
 120         WMCreateEventHandler(mPtr->view, ButtonPressMask, handleActionEvents, mPtr);
 121
 122         return mPtr;
 123 }
 124
 125 /*
 126  * Paint our widget contents.
 127  */
 128 static void paintMyWidget(_MyWidget * mPtr)
 129 {
 130         W_Screen *scr = mPtr->view->screen;
 131         WMColor *color;
 132
 133         if (mPtr->text) {
 134
 135                 color = WMWhiteColor(scr);
 136
 137                 W_PaintText(mPtr->view, mPtr->view->window, scr->normalFont, 0, 0,
 138                             mPtr->view->size.width, WACenter, color, False, mPtr->text, strlen(mPtr->text));
 139
 140                 WMReleaseColor(color);
 141         }
 142 }
 143
 144 static void handleEvents(XEvent * event, void *data)
 145 {
 146         _MyWidget *mPtr = (_MyWidget *) data;
 147
 148         switch (event->type) {
 149         case Expose:
 150                 if (event->xexpose.count != 0)
 151                         break;
 152                 paintMyWidget(mPtr);
 153                 break;
 154
 155         case DestroyNotify:
 156                 destroyMyWidget(mPtr);
 157                 break;
 158
 159         }
 160 }
 161
 162 static void handleActionEvents(XEvent * event, void *data)
 163 {
 164         _MyWidget *mPtr = (_MyWidget *) data;
 165
 166         switch (event->type) {
 167         case ButtonPress:
 168                 XBell(mPtr->view->screen->display, 100);
 169                 XBell(mPtr->view->screen->display, 100);
 170                 break;
 171         }
 172 }
 173
 174 void SetMyWidgetText(MyWidget * mPtr, char *text)
 175 {
 176         CHECK_CLASS(mPtr, myWidgetClass);
 177
 178         if (mPtr->text)
 179                 wfree(mPtr->text);
 180
 181         mPtr->text = wstrdup(text);
 182
 183         if (W_VIEW_MAPPED(mPtr->view)) {
 184                 paintMyWidget(mPtr);
 185         }
 186 }
 187
 188 static void destroyMyWidget(_MyWidget * mPtr)
 189 {
 190         /*
 191          * Free all data we allocated for our widget.
 192          */
 193
 194         if (mPtr->text)
 195                 wfree(mPtr->text);
 196
 197         wfree(mPtr);
 198 }