src/gtk/win_gtk.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/gtk/win_gtk.cpp
   3 // Purpose:     native GTK+ widget for wxWindow
   4 // Author:      Paul Cornett
   5 // Id:          $Id$
   6 // Copyright:   (c) 2007 Paul Cornett
   7 // Licence:     wxWindows licence
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 #include "wx/defs.h"
  11 #include "wx/gtk/private.h"
  12 #include "wx/gtk/private/win_gtk.h"
  13
  14 /*
  15 wxPizza is a custom GTK+ widget derived from GtkFixed.  A custom widget
  16 is needed to adapt GTK+ to wxWidgets needs in 3 areas: scrolling, window
  17 borders, and RTL.
  18
  19 For scrolling, the "set_scroll_adjustments" signal is implemented
  20 to make wxPizza appear scrollable to GTK+, allowing it to be put in a
  21 GtkScrolledWindow.  Child widget positions are adjusted for the scrolling
  22 position in size_allocate.  A second same-size GdkWindow is placed behind
  23 widget->window, to allow GDK to use a more efficient scrolling technique.
  24
  25 For borders, space is reserved in realize and size_allocate.  The border is
  26 drawn on wxPizza's parent GdkWindow.
  27
  28 For RTL, child widget positions are mirrored in size_allocate.
  29 */
  30
  31 static GtkWidgetClass* parent_class;
  32
  33 extern "C" {
  34
  35 struct wxPizzaClass
  36 {
  37     GtkFixedClass parent;
  38     void (*set_scroll_adjustments)(GtkWidget*, GtkAdjustment*, GtkAdjustment*);
  39 };
  40
  41 static void size_allocate(GtkWidget* widget, GtkAllocation* alloc)
  42 {
  43     const bool is_resize =
  44         widget->allocation.width  != alloc->width ||
  45         widget->allocation.height != alloc->height;
  46     const bool is_move =
  47         widget->allocation.x != alloc->x ||
  48         widget->allocation.y != alloc->y;
  49
  50     widget->allocation = *alloc;
  51
  52     wxPizza* pizza = WX_PIZZA(widget);
  53     int border_x, border_y;
  54     pizza->get_border_widths(border_x, border_y);
  55     int w = alloc->width - 2 * border_x;
  56     if (w < 0) w = 0;
  57
  58     if (GTK_WIDGET_REALIZED(widget) && (is_move || is_resize))
  59     {
  60         int h = alloc->height - 2 * border_y;
  61         if (h < 0) h = 0;
  62
  63         if (pizza->m_is_scrollable)
  64         {
  65             // two windows, both same size
  66             gdk_window_move_resize(pizza->m_backing_window,
  67                 alloc->x + border_x, alloc->y + border_y, w, h);
  68             if (is_resize)
  69                 gdk_window_resize(widget->window, w, h);
  70         }
  71         else
  72         {
  73             // one window
  74             gdk_window_move_resize(widget->window,
  75                 alloc->x + border_x, alloc->y + border_y, w, h);
  76
  77             if ((border_x > 0) || (border_y > 0))
  78             {
  79                 // Otherwise we get can redraw artefacts from
  80                 // the border.
  81                 GtkWidget *parent = gtk_widget_get_parent( widget );
  82                 gtk_widget_queue_draw( parent );
  83             }
  84         }
  85     }
  86     // adjust child positions
  87     for (const GList* list = pizza->m_fixed.children; list; list = list->next)
  88     {
  89         const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
  90         if (GTK_WIDGET_VISIBLE(child->widget))
  91         {
  92             GtkAllocation child_alloc;
  93             // note that child positions do not take border into
  94             // account, they need to be relative to widget->window,
  95             // which has already been adjusted
  96             child_alloc.x = child->x - pizza->m_scroll_x;
  97             child_alloc.y = child->y - pizza->m_scroll_y;
  98             GtkRequisition req;
  99             gtk_widget_get_child_requisition(child->widget, &req);
 100             child_alloc.width  = req.width;
 101             child_alloc.height = req.height;
 102             if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
 103             {
 104                 child_alloc.x = w - child_alloc.x - child_alloc.width;
 105             }
 106             gtk_widget_size_allocate(child->widget, &child_alloc);
 107         }
 108     }
 109 }
 110
 111 static void realize(GtkWidget* widget)
 112 {
 113     parent_class->realize(widget);
 114
 115     wxPizza* pizza = WX_PIZZA(widget);
 116     if (pizza->m_border_style || pizza->m_is_scrollable)
 117     {
 118         int border_x, border_y;
 119         pizza->get_border_widths(border_x, border_y);
 120         int x = widget->allocation.x + border_x;
 121         int y = widget->allocation.y + border_y;
 122         int w = widget->allocation.width  - 2 * border_x;
 123         int h = widget->allocation.height - 2 * border_y;
 124         if (w < 0) w = 0;
 125         if (h < 0) h = 0;
 126         if (pizza->m_is_scrollable)
 127         {
 128             // second window is created if wxWindow is scrollable
 129             GdkWindowAttr attr;
 130             attr.event_mask = 0;
 131             attr.x = x;
 132             attr.y = y;
 133             attr.width  = w;
 134             attr.height = h;
 135             attr.wclass = GDK_INPUT_OUTPUT;
 136             attr.visual = gtk_widget_get_visual(widget);
 137             attr.colormap = gtk_widget_get_colormap(widget);
 138             attr.window_type = GDK_WINDOW_CHILD;
 139
 140             pizza->m_backing_window = gdk_window_new(
 141                 gdk_window_get_parent(widget->window),
 142                 &attr,
 143                 GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP);
 144
 145             gdk_window_set_user_data(pizza->m_backing_window, widget);
 146             gdk_window_reparent(widget->window, pizza->m_backing_window, 0, 0);
 147             gdk_window_resize(widget->window, w, h);
 148
 149             // Parts of m_backing_window may be exposed temporarily while
 150             // resizing. Setting the backing pixmap to None prevents those
 151             // areas from being briefly painted black.
 152             gdk_window_set_back_pixmap(pizza->m_backing_window, NULL, false);
 153         }
 154         else
 155             gdk_window_move_resize(widget->window, x, y, w, h);
 156     }
 157 }
 158
 159 static void unrealize(GtkWidget* widget)
 160 {
 161     parent_class->unrealize(widget);
 162
 163     wxPizza* pizza = WX_PIZZA(widget);
 164     if (pizza->m_backing_window)
 165     {
 166         gdk_window_set_user_data(pizza->m_backing_window, NULL);
 167         gdk_window_destroy(pizza->m_backing_window);
 168         pizza->m_backing_window = NULL;
 169     }
 170 }
 171
 172 static void map(GtkWidget* widget)
 173 {
 174     parent_class->map(widget);
 175
 176     wxPizza* pizza = WX_PIZZA(widget);
 177     if (pizza->m_backing_window)
 178         gdk_window_show(pizza->m_backing_window);
 179 }
 180
 181 static void unmap(GtkWidget* widget)
 182 {
 183     parent_class->unmap(widget);
 184
 185     wxPizza* pizza = WX_PIZZA(widget);
 186     if (pizza->m_backing_window)
 187         gdk_window_hide(pizza->m_backing_window);
 188 }
 189
 190 // not used, but needs to exist so gtk_widget_set_scroll_adjustments will work
 191 static void set_scroll_adjustments(GtkWidget*, GtkAdjustment*, GtkAdjustment*)
 192 {
 193 }
 194
 195 // Marshaller needed for set_scroll_adjustments signal,
 196 // generated with GLib-2.4.6 glib-genmarshal
 197 #define g_marshal_value_peek_object(v)   g_value_get_object (v)
 198 static void
 199 g_cclosure_user_marshal_VOID__OBJECT_OBJECT (GClosure     *closure,
 200                                              GValue       * /*return_value*/,
 201                                              guint         n_param_values,
 202                                              const GValue *param_values,
 203                                              gpointer      /*invocation_hint*/,
 204                                              gpointer      marshal_data)
 205 {
 206   typedef void (*GMarshalFunc_VOID__OBJECT_OBJECT) (gpointer     data1,
 207                                                     gpointer     arg_1,
 208                                                     gpointer     arg_2,
 209                                                     gpointer     data2);
 210   register GMarshalFunc_VOID__OBJECT_OBJECT callback;
 211   register GCClosure *cc = (GCClosure*) closure;
 212   register gpointer data1, data2;
 213
 214   g_return_if_fail (n_param_values == 3);
 215
 216   if (G_CCLOSURE_SWAP_DATA (closure))
 217     {
 218       data1 = closure->data;
 219       data2 = g_value_peek_pointer (param_values + 0);
 220     }
 221   else
 222     {
 223       data1 = g_value_peek_pointer (param_values + 0);
 224       data2 = closure->data;
 225     }
 226   callback = (GMarshalFunc_VOID__OBJECT_OBJECT) (marshal_data ? marshal_data : cc->callback);
 227
 228   callback (data1,
 229             g_marshal_value_peek_object (param_values + 1),
 230             g_marshal_value_peek_object (param_values + 2),
 231             data2);
 232 }
 233
 234 static void class_init(void* g_class, void*)
 235 {
 236     GtkWidgetClass* widget_class = (GtkWidgetClass*)g_class;
 237     widget_class->size_allocate = size_allocate;
 238     widget_class->realize = realize;
 239     widget_class->unrealize = unrealize;
 240     widget_class->map = map;
 241     widget_class->unmap = unmap;
 242     wxPizzaClass* klass = (wxPizzaClass*)g_class;
 243
 244     // needed to make widget appear scrollable to GTK+
 245     klass->set_scroll_adjustments = set_scroll_adjustments;
 246     widget_class->set_scroll_adjustments_signal =
 247         g_signal_new(
 248             "set_scroll_adjustments",
 249             G_TYPE_FROM_CLASS(g_class),
 250             G_SIGNAL_RUN_LAST,
 251             G_STRUCT_OFFSET(wxPizzaClass, set_scroll_adjustments),
 252             NULL, NULL,
 253             g_cclosure_user_marshal_VOID__OBJECT_OBJECT,
 254             G_TYPE_NONE, 2, GTK_TYPE_ADJUSTMENT, GTK_TYPE_ADJUSTMENT);
 255
 256     parent_class = GTK_WIDGET_CLASS(g_type_class_peek_parent(g_class));
 257 }
 258
 259 } // extern "C"
 260
 261 GType wxPizza::type()
 262 {
 263     static GtkType type;
 264     if (type == 0)
 265     {
 266         const GTypeInfo info = {
 267             sizeof(wxPizzaClass),
 268             NULL, NULL,
 269             class_init,
 270             NULL, NULL,
 271             sizeof(wxPizza), 0,
 272             NULL, NULL
 273         };
 274         type = g_type_register_static(
 275             GTK_TYPE_FIXED, "wxPizza", &info, GTypeFlags(0));
 276     }
 277     return type;
 278 }
 279
 280 GtkWidget* wxPizza::New(long windowStyle)
 281 {
 282     GtkWidget* widget = GTK_WIDGET(g_object_new(type(), NULL));
 283     wxPizza* pizza = WX_PIZZA(widget);
 284     pizza->m_backing_window = NULL;
 285     pizza->m_scroll_x = 0;
 286     pizza->m_scroll_y = 0;
 287     pizza->m_is_scrollable = (windowStyle & (wxHSCROLL | wxVSCROLL)) != 0;
 288     // mask off border styles not useable with wxPizza
 289     pizza->m_border_style = int(windowStyle & BORDER_STYLES);
 290     gtk_fixed_set_has_window(GTK_FIXED(widget), true);
 291     gtk_widget_add_events(widget,
 292         GDK_EXPOSURE_MASK |
 293         GDK_SCROLL_MASK |
 294         GDK_POINTER_MOTION_MASK |
 295         GDK_POINTER_MOTION_HINT_MASK |
 296         GDK_BUTTON_MOTION_MASK |
 297         GDK_BUTTON1_MOTION_MASK |
 298         GDK_BUTTON2_MOTION_MASK |
 299         GDK_BUTTON3_MOTION_MASK |
 300         GDK_BUTTON_PRESS_MASK |
 301         GDK_BUTTON_RELEASE_MASK |
 302         GDK_KEY_PRESS_MASK |
 303         GDK_KEY_RELEASE_MASK |
 304         GDK_ENTER_NOTIFY_MASK |
 305         GDK_LEAVE_NOTIFY_MASK |
 306         GDK_FOCUS_CHANGE_MASK);
 307     return widget;
 308 }
 309
 310 // gtk_fixed_move does not check for a change before issuing a queue_resize,
 311 // we need to avoid that to prevent endless sizing loops, so check first
 312 void wxPizza::move(GtkWidget* widget, int x, int y)
 313 {
 314     GtkFixed* fixed = &m_fixed;
 315     for (const GList* list = fixed->children; list; list = list->next)
 316     {
 317         const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
 318         if (child->widget == widget)
 319         {
 320             if (child->x != x || child->y != y)
 321                 gtk_fixed_move(fixed, widget, x, y);
 322             break;
 323         }
 324     }
 325 }
 326
 327 struct AdjustData {
 328     GdkWindow* window;
 329     int dx, dy;
 330 };
 331
 332 // Adjust allocations for all widgets using the GdkWindow which was just scrolled
 333 extern "C" {
 334 static void scroll_adjust(GtkWidget* widget, void* data)
 335 {
 336     const AdjustData* p = static_cast<AdjustData*>(data);
 337     if (widget->window == p->window)
 338     {
 339         widget->allocation.x += p->dx;
 340         widget->allocation.y += p->dy;
 341         // GtkFrame requires a queue_resize, otherwise parts of
 342         // the frame newly exposed by the scroll are not drawn.
 343         // To be safe, do it for all widgets.
 344         gtk_widget_queue_resize_no_redraw(widget);
 345         if (GTK_IS_CONTAINER(widget))
 346             gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, data);
 347     }
 348 }
 349 }
 350
 351 void wxPizza::scroll(int dx, int dy)
 352 {
 353     GtkWidget* widget = GTK_WIDGET(this);
 354     if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
 355         dx = -dx;
 356     m_scroll_x -= dx;
 357     m_scroll_y -= dy;
 358     if (widget->window)
 359     {
 360         gdk_window_scroll(widget->window, dx, dy);
 361         // Adjust child allocations. Doing a queue_resize on the children is not
 362         // enough, sometimes they redraw in the wrong place during fast scrolling.
 363         AdjustData data = { widget->window, dx, dy };
 364         gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, &data);
 365     }
 366 }
 367
 368 void wxPizza::get_border_widths(int& x, int& y)
 369 {
 370     x = y = 0;
 371 #ifndef __WXUNIVERSAL__
 372     if (m_border_style & wxBORDER_SIMPLE)
 373         x = y = 1;
 374     else if (m_border_style)
 375     {
 376         GtkWidget *entry_widget = wxGTKPrivate::GetEntryWidget();
 377         if (entry_widget->style)
 378         {
 379             x = entry_widget->style->xthickness;
 380             y = entry_widget->style->ythickness;
 381         }
 382     }
 383 #endif
 384 }