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