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.
  26 For non-scrolling wxWindows, a second GdkWindow is used for the
  27 border; scrolling wxWindows draw their border on wxPizza's parent
  28 (a GtkScrolledWindow) GdkWindow.  Border widths for sunken and raised
  29 styles are taken from widget->style, so they will match the current theme.
  30
  31 For RTL, child widget positions are mirrored in size_allocate.
  32 */
  33
  34 static GtkWidgetClass* parent_class;
  35
  36 extern "C" {
  37
  38 struct wxPizzaClass
  39 {
  40     GtkFixedClass parent;
  41     void (*set_scroll_adjustments)(GtkWidget*, GtkAdjustment*, GtkAdjustment*);
  42 };
  43
  44 static void size_allocate(GtkWidget* widget, GtkAllocation* alloc)
  45 {
  46     const bool is_resize =
  47         widget->allocation.width  != alloc->width ||
  48         widget->allocation.height != alloc->height;
  49     const bool is_move =
  50         widget->allocation.x != alloc->x ||
  51         widget->allocation.y != alloc->y;
  52
  53     widget->allocation = *alloc;
  54
  55     wxPizza* pizza = WX_PIZZA(widget);
  56     int border_x, border_y;
  57     pizza->get_border_widths(border_x, border_y);
  58     int w = alloc->width - 2 * border_x;
  59     if (w < 0) w = 0;
  60
  61     if (GTK_WIDGET_REALIZED(widget) && (is_move || is_resize))
  62     {
  63         int h = alloc->height - 2 * border_y;
  64         if (h < 0) h = 0;
  65
  66         if (pizza->m_is_scrollable)
  67         {
  68             // two windows, both same size
  69             gdk_window_move_resize(pizza->m_backing_window,
  70                 alloc->x + border_x, alloc->y + border_y, w, h);
  71             if (is_resize)
  72                 gdk_window_resize(widget->window, w, h);
  73         }
  74         else if (pizza->m_backing_window)
  75         {
  76             // two windows, widget->window is smaller by border widths (need to
  77             // move widget->window as well as resize because border can change)
  78             gdk_window_move_resize(pizza->m_backing_window,
  79                 alloc->x, alloc->y, alloc->width, alloc->height);
  80             gdk_window_move_resize(widget->window, border_x, border_y, w, h);
  81         }
  82         else
  83         {
  84             // one window
  85             gdk_window_move_resize(widget->window,
  86                 alloc->x, alloc->y, alloc->width, alloc->height);
  87         }
  88         if (is_resize && pizza->m_backing_window)
  89         {
  90             // wxWidgets turns off redraw-on-allocate by default,
  91             // so border area needs to be invalidated
  92             if (border_x > 1 || border_y > 1)
  93             {
  94                 if (pizza->m_is_scrollable)
  95                     ; // invalidate does not seem to be needed in this case
  96                 else
  97                     gdk_window_invalidate_rect(pizza->m_backing_window, NULL, false);
  98             }
  99         }
 100     }
 101     // adjust child positions
 102     for (const GList* list = pizza->m_fixed.children; list; list = list->next)
 103     {
 104         const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
 105         if (GTK_WIDGET_VISIBLE(child->widget))
 106         {
 107             GtkAllocation child_alloc;
 108             // note that child positions do not take border into
 109             // account, they need to be relative to widget->window,
 110             // which has already been adjusted
 111             child_alloc.x = child->x - pizza->m_scroll_x;
 112             child_alloc.y = child->y - pizza->m_scroll_y;
 113             GtkRequisition req;
 114             gtk_widget_get_child_requisition(child->widget, &req);
 115             child_alloc.width  = req.width;
 116             child_alloc.height = req.height;
 117             if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
 118             {
 119                 child_alloc.x = w - child_alloc.x - child_alloc.width;
 120             }
 121             gtk_widget_size_allocate(child->widget, &child_alloc);
 122         }
 123     }
 124 }
 125
 126 static void realize(GtkWidget* widget)
 127 {
 128     parent_class->realize(widget);
 129
 130     wxPizza* pizza = WX_PIZZA(widget);
 131     // second window is created if there is a border, or wxWindow is scrollable
 132     if (pizza->m_border_style || pizza->m_is_scrollable)
 133     {
 134         GdkWindowAttr attr;
 135         attr.event_mask = pizza->m_is_scrollable ? 0 : GDK_EXPOSURE_MASK;
 136         attr.x = widget->allocation.x;
 137         attr.y = widget->allocation.y;
 138         attr.width = widget->allocation.width;
 139         attr.height = widget->allocation.height;
 140         int border_x, border_y;
 141         pizza->get_border_widths(border_x, border_y);
 142         int w = widget->allocation.width  - 2 * border_x;
 143         int h = widget->allocation.height - 2 * border_y;
 144         if (w < 0) w = 0;
 145         if (h < 0) h = 0;
 146         if (pizza->m_is_scrollable)
 147         {
 148             attr.x += border_x;
 149             attr.y += border_y;
 150             attr.width  = w;
 151             attr.height = h;
 152         }
 153         attr.wclass = GDK_INPUT_OUTPUT;
 154         attr.visual = gtk_widget_get_visual(widget);
 155         attr.colormap = gtk_widget_get_colormap(widget);
 156         attr.window_type = GDK_WINDOW_CHILD;
 157
 158         pizza->m_backing_window = gdk_window_new(
 159             gdk_window_get_parent(widget->window),
 160             &attr,
 161             GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP);
 162
 163         gdk_window_set_user_data(pizza->m_backing_window, widget);
 164         if (pizza->m_is_scrollable)
 165             gdk_window_reparent(widget->window, pizza->m_backing_window, 0, 0);
 166         else
 167             gdk_window_reparent(widget->window, pizza->m_backing_window, border_x, border_y);
 168         gdk_window_resize(widget->window, w, h);
 169
 170         // Parts of m_backing_window which are supposed to be obscured may be
 171         // exposed temporarily while resizing. Setting the backing pixmap to
 172         // None prevents those areas from being briefly painted black.
 173         gdk_window_set_back_pixmap(pizza->m_backing_window, NULL, false);
 174     }
 175 }
 176
 177 static void unrealize(GtkWidget* widget)
 178 {
 179     parent_class->unrealize(widget);
 180
 181     wxPizza* pizza = WX_PIZZA(widget);
 182     if (pizza->m_backing_window)
 183     {
 184         gdk_window_set_user_data(pizza->m_backing_window, NULL);
 185         gdk_window_destroy(pizza->m_backing_window);
 186         pizza->m_backing_window = NULL;
 187     }
 188 }
 189
 190 static void map(GtkWidget* widget)
 191 {
 192     parent_class->map(widget);
 193
 194     wxPizza* pizza = WX_PIZZA(widget);
 195     if (pizza->m_backing_window)
 196         gdk_window_show(pizza->m_backing_window);
 197 }
 198
 199 static void unmap(GtkWidget* widget)
 200 {
 201     parent_class->unmap(widget);
 202
 203     wxPizza* pizza = WX_PIZZA(widget);
 204     if (pizza->m_backing_window)
 205         gdk_window_hide(pizza->m_backing_window);
 206 }
 207
 208 // not used, but needs to exist so gtk_widget_set_scroll_adjustments will work
 209 static void set_scroll_adjustments(GtkWidget*, GtkAdjustment*, GtkAdjustment*)
 210 {
 211 }
 212
 213 // Marshaller needed for set_scroll_adjustments signal,
 214 // generated with GLib-2.4.6 glib-genmarshal
 215 #define g_marshal_value_peek_object(v)   g_value_get_object (v)
 216 static void
 217 g_cclosure_user_marshal_VOID__OBJECT_OBJECT (GClosure     *closure,
 218                                              GValue       * /*return_value*/,
 219                                              guint         n_param_values,
 220                                              const GValue *param_values,
 221                                              gpointer      /*invocation_hint*/,
 222                                              gpointer      marshal_data)
 223 {
 224   typedef void (*GMarshalFunc_VOID__OBJECT_OBJECT) (gpointer     data1,
 225                                                     gpointer     arg_1,
 226                                                     gpointer     arg_2,
 227                                                     gpointer     data2);
 228   register GMarshalFunc_VOID__OBJECT_OBJECT callback;
 229   register GCClosure *cc = (GCClosure*) closure;
 230   register gpointer data1, data2;
 231
 232   g_return_if_fail (n_param_values == 3);
 233
 234   if (G_CCLOSURE_SWAP_DATA (closure))
 235     {
 236       data1 = closure->data;
 237       data2 = g_value_peek_pointer (param_values + 0);
 238     }
 239   else
 240     {
 241       data1 = g_value_peek_pointer (param_values + 0);
 242       data2 = closure->data;
 243     }
 244   callback = (GMarshalFunc_VOID__OBJECT_OBJECT) (marshal_data ? marshal_data : cc->callback);
 245
 246   callback (data1,
 247             g_marshal_value_peek_object (param_values + 1),
 248             g_marshal_value_peek_object (param_values + 2),
 249             data2);
 250 }
 251
 252 static void class_init(void* g_class, void*)
 253 {
 254     GtkWidgetClass* widget_class = (GtkWidgetClass*)g_class;
 255     widget_class->size_allocate = size_allocate;
 256     widget_class->realize = realize;
 257     widget_class->unrealize = unrealize;
 258     widget_class->map = map;
 259     widget_class->unmap = unmap;
 260     wxPizzaClass* klass = (wxPizzaClass*)g_class;
 261
 262     // needed to make widget appear scrollable to GTK+
 263     klass->set_scroll_adjustments = set_scroll_adjustments;
 264     widget_class->set_scroll_adjustments_signal =
 265         g_signal_new(
 266             "set_scroll_adjustments",
 267             G_TYPE_FROM_CLASS(g_class),
 268             G_SIGNAL_RUN_LAST,
 269             G_STRUCT_OFFSET(wxPizzaClass, set_scroll_adjustments),
 270             NULL, NULL,
 271             g_cclosure_user_marshal_VOID__OBJECT_OBJECT,
 272             G_TYPE_NONE, 2, GTK_TYPE_ADJUSTMENT, GTK_TYPE_ADJUSTMENT);
 273
 274     parent_class = GTK_WIDGET_CLASS(g_type_class_peek_parent(g_class));
 275 }
 276
 277 } // extern "C"
 278
 279 GType wxPizza::type()
 280 {
 281     static GtkType type;
 282     if (type == 0)
 283     {
 284         const GTypeInfo info = {
 285             sizeof(wxPizzaClass),
 286             NULL, NULL,
 287             class_init,
 288             NULL, NULL,
 289             sizeof(wxPizza), 0,
 290             NULL, NULL
 291         };
 292         type = g_type_register_static(
 293             GTK_TYPE_FIXED, "wxPizza", &info, GTypeFlags(0));
 294     }
 295     return type;
 296 }
 297
 298 GtkWidget* wxPizza::New(long windowStyle)
 299 {
 300     GtkWidget* widget = GTK_WIDGET(g_object_new(type(), NULL));
 301     wxPizza* pizza = WX_PIZZA(widget);
 302     pizza->m_backing_window = NULL;
 303     pizza->m_scroll_x = 0;
 304     pizza->m_scroll_y = 0;
 305     pizza->m_is_scrollable = (windowStyle & (wxHSCROLL | wxVSCROLL)) != 0;
 306     // mask off border styles not useable with wxPizza
 307     pizza->m_border_style = int(windowStyle & BORDER_STYLES);
 308     gtk_fixed_set_has_window(GTK_FIXED(widget), true);
 309     gtk_widget_add_events(widget,
 310         GDK_EXPOSURE_MASK |
 311         GDK_SCROLL_MASK |
 312         GDK_POINTER_MOTION_MASK |
 313         GDK_POINTER_MOTION_HINT_MASK |
 314         GDK_BUTTON_MOTION_MASK |
 315         GDK_BUTTON1_MOTION_MASK |
 316         GDK_BUTTON2_MOTION_MASK |
 317         GDK_BUTTON3_MOTION_MASK |
 318         GDK_BUTTON_PRESS_MASK |
 319         GDK_BUTTON_RELEASE_MASK |
 320         GDK_KEY_PRESS_MASK |
 321         GDK_KEY_RELEASE_MASK |
 322         GDK_ENTER_NOTIFY_MASK |
 323         GDK_LEAVE_NOTIFY_MASK |
 324         GDK_FOCUS_CHANGE_MASK);
 325     return widget;
 326 }
 327
 328 // gtk_fixed_move does not check for a change before issuing a queue_resize,
 329 // we need to avoid that to prevent endless sizing loops, so check first
 330 void wxPizza::move(GtkWidget* widget, int x, int y)
 331 {
 332     GtkFixed* fixed = &m_fixed;
 333     for (const GList* list = fixed->children; list; list = list->next)
 334     {
 335         const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
 336         if (child->widget == widget)
 337         {
 338             if (child->x != x || child->y != y)
 339                 gtk_fixed_move(fixed, widget, x, y);
 340             break;
 341         }
 342     }
 343 }
 344
 345 struct AdjustData {
 346     GdkWindow* window;
 347     int dx, dy;
 348 };
 349
 350 // Adjust allocations for all widgets using the GdkWindow which was just scrolled
 351 extern "C" {
 352 static void scroll_adjust(GtkWidget* widget, void* data)
 353 {
 354     const AdjustData* p = static_cast<AdjustData*>(data);
 355     if (widget->window == p->window)
 356     {
 357         widget->allocation.x += p->dx;
 358         widget->allocation.y += p->dy;
 359         // GtkFrame requires a queue_resize, otherwise parts of
 360         // the frame newly exposed by the scroll are not drawn.
 361         // To be safe, do it for all widgets.
 362         gtk_widget_queue_resize_no_redraw(widget);
 363         if (GTK_IS_CONTAINER(widget))
 364             gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, data);
 365     }
 366 }
 367 }
 368
 369 void wxPizza::scroll(int dx, int dy)
 370 {
 371     GtkWidget* widget = GTK_WIDGET(this);
 372     if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
 373         dx = -dx;
 374     m_scroll_x -= dx;
 375     m_scroll_y -= dy;
 376     if (widget->window)
 377     {
 378         gdk_window_scroll(widget->window, dx, dy);
 379         // Adjust child allocations. Doing a queue_resize on the children is not
 380         // enough, sometimes they redraw in the wrong place during fast scrolling.
 381         AdjustData data = { widget->window, dx, dy };
 382         gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, &data);
 383     }
 384 }
 385
 386 void wxPizza::get_border_widths(int& x, int& y)
 387 {
 388     x = y = 0;
 389     if (m_border_style & wxBORDER_SIMPLE)
 390         x = y = 1;
 391     else if (m_border_style)
 392     {
 393         GtkWidget *entry_widget = wxGTKPrivate::GetEntryWidget();
 394         if (entry_widget->style)
 395         {
 396             x = entry_widget->style->xthickness;
 397             y = entry_widget->style->ythickness;
 398         }
 399     }
 400 }