gtkviewport.c

gtk是linux一款强大的夸平台的图形化开发工具

  bin = GTK_BIN (widget);
  viewport = GTK_VIEWPORT (widget);
  GTK_WIDGET_SET_FLAGS (widget, GTK_REALIZED);

  attributes.x = widget->allocation.x + border_width;
  attributes.y = widget->allocation.y + border_width;
  attributes.width = widget->allocation.width - border_width * 2;
  attributes.height = widget->allocation.height - border_width * 2;
  attributes.window_type = GDK_WINDOW_CHILD;
  attributes.wclass = GDK_INPUT_OUTPUT;
  attributes.visual = gtk_widget_get_visual (widget);
  attributes.colormap = gtk_widget_get_colormap (widget);

  event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
  /* We select on button_press_mask so that button 4-5 scrolls are trapped.
   */
  attributes.event_mask = event_mask | GDK_BUTTON_PRESS_MASK;

  attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;

  widget->window = gdk_window_new (gtk_widget_get_parent_window (widget),
				   &attributes, attributes_mask);
  gdk_window_set_user_data (widget->window, viewport);

  if (viewport->shadow_type != GTK_SHADOW_NONE)
    {
      attributes.x = widget->style->klass->xthickness;
      attributes.y = widget->style->klass->ythickness;
    }
  else
    {
      attributes.x = 0;
      attributes.y = 0;
    }

  attributes.width = MAX (1, (gint)widget->allocation.width - attributes.x * 2 - border_width * 2);
  attributes.height = MAX (1, (gint)widget->allocation.height - attributes.y * 2 - border_width * 2);
  attributes.event_mask = 0;

  viewport->view_window = gdk_window_new (widget->window, &attributes, attributes_mask);
  gdk_window_set_user_data (viewport->view_window, viewport);

  attributes.x = 0;
  attributes.y = 0;

  if (bin->child)
    {
      attributes.width = viewport->hadjustment->upper;
      attributes.height = viewport->vadjustment->upper;
    }
  
  attributes.event_mask = event_mask;

  viewport->bin_window = gdk_window_new (viewport->view_window, &attributes, attributes_mask);
  gdk_window_set_user_data (viewport->bin_window, viewport);

  if (bin->child)
    gtk_widget_set_parent_window (bin->child, viewport->bin_window);

  widget->style = gtk_style_attach (widget->style, widget->window);
  gtk_style_set_background (widget->style, widget->window, GTK_STATE_NORMAL);
  gtk_style_set_background (widget->style, viewport->bin_window, GTK_STATE_NORMAL);

   gtk_paint_flat_box(widget->style, viewport->bin_window, GTK_STATE_NORMAL,
		      GTK_SHADOW_NONE,
		      NULL, widget, "viewportbin",
		      0, 0, -1, -1);
   
  gdk_window_show (viewport->bin_window);
  gdk_window_show (viewport->view_window);
}

static void
gtk_viewport_unrealize (GtkWidget *widget)
{
  GtkViewport *viewport;

  g_return_if_fail (widget != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (widget));

  viewport = GTK_VIEWPORT (widget);

  gdk_window_set_user_data (viewport->view_window, NULL);
  gdk_window_destroy (viewport->view_window);
  viewport->view_window = NULL;

  gdk_window_set_user_data (viewport->bin_window, NULL);
  gdk_window_destroy (viewport->bin_window);
  viewport->bin_window = NULL;

  if (GTK_WIDGET_CLASS (parent_class)->unrealize)
    (* GTK_WIDGET_CLASS (parent_class)->unrealize) (widget);
}

static void
gtk_viewport_paint (GtkWidget    *widget,
		    GdkRectangle *area)
{
  GtkViewport *viewport;

  g_return_if_fail (widget != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (widget));
  g_return_if_fail (area != NULL);

  if (GTK_WIDGET_DRAWABLE (widget))
    {
      viewport = GTK_VIEWPORT (widget);

      gtk_draw_shadow (widget->style, widget->window,
		       GTK_STATE_NORMAL, viewport->shadow_type,
		       0, 0, -1, -1);
    }
}

static void
gtk_viewport_draw (GtkWidget    *widget,
		   GdkRectangle *area)
{
  GtkViewport *viewport;
  GtkBin *bin;
  GdkRectangle tmp_area;
  GdkRectangle child_area;
  gint border_width;

  g_return_if_fail (widget != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (widget));
  g_return_if_fail (area != NULL);

  if (GTK_WIDGET_DRAWABLE (widget))
    {
      viewport = GTK_VIEWPORT (widget);
      bin = GTK_BIN (widget);

      border_width = GTK_CONTAINER (widget)->border_width;
      
      tmp_area = *area;
      tmp_area.x -= border_width;
      tmp_area.y -= border_width;
      
      gtk_viewport_paint (widget, &tmp_area);

      tmp_area.x += viewport->hadjustment->value - widget->style->klass->xthickness;
      tmp_area.y += viewport->vadjustment->value - widget->style->klass->ythickness;
      
      gtk_paint_flat_box(widget->style, viewport->bin_window, 
			 GTK_STATE_NORMAL, GTK_SHADOW_NONE,
			 &tmp_area, widget, "viewportbin",
			 0, 0, -1, -1);

      if (bin->child)
	{
	  if (gtk_widget_intersect (bin->child, &tmp_area, &child_area))
	    gtk_widget_draw (bin->child, &child_area);
	}
    }
}

static gint
gtk_viewport_expose (GtkWidget      *widget,
		     GdkEventExpose *event)
{
  GtkViewport *viewport;
  GtkBin *bin;
  GdkEventExpose child_event;

  g_return_val_if_fail (widget != NULL, FALSE);
  g_return_val_if_fail (GTK_IS_VIEWPORT (widget), FALSE);
  g_return_val_if_fail (event != NULL, FALSE);

  if (GTK_WIDGET_DRAWABLE (widget))
    {
      viewport = GTK_VIEWPORT (widget);
      bin = GTK_BIN (widget);

      if (event->window == widget->window)
	gtk_viewport_paint (widget, &event->area);
      else if (event->window == viewport->bin_window)
	{
	  child_event = *event;

	  gtk_paint_flat_box(widget->style, viewport->bin_window, 
			     GTK_STATE_NORMAL, GTK_SHADOW_NONE,
			     &event->area, widget, "viewportbin",
			     0, 0, -1, -1);
	  
	  if ((bin->child != NULL) &&
	      GTK_WIDGET_NO_WINDOW (bin->child) &&
	      gtk_widget_intersect (bin->child, &event->area, &child_event.area))
	    gtk_widget_event (bin->child, (GdkEvent*) &child_event);
	}
	

    }

  return FALSE;
}

static void
gtk_viewport_add (GtkContainer *container,
		  GtkWidget    *child)
{
  GtkBin *bin;

  g_return_if_fail (container != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (container));
  g_return_if_fail (child != NULL);

  bin = GTK_BIN (container);
  g_return_if_fail (bin->child == NULL);

  gtk_widget_set_parent_window (child, GTK_VIEWPORT (bin)->bin_window);

  GTK_CONTAINER_CLASS (parent_class)->add (container, child);
}

static void
gtk_viewport_size_request (GtkWidget      *widget,
			   GtkRequisition *requisition)
{
  GtkViewport *viewport;
  GtkBin *bin;
  GtkRequisition child_requisition;

  g_return_if_fail (widget != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (widget));
  g_return_if_fail (requisition != NULL);

  viewport = GTK_VIEWPORT (widget);
  bin = GTK_BIN (widget);

  requisition->width = (GTK_CONTAINER (widget)->border_width +
			GTK_WIDGET (widget)->style->klass->xthickness) * 2 + 5;

  requisition->height = (GTK_CONTAINER (widget)->border_width * 2 +
			 GTK_WIDGET (widget)->style->klass->ythickness) * 2 + 5;

  if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
    {
      gtk_widget_size_request (bin->child, &child_requisition);
      requisition->width += child_requisition.width;
      requisition->height += child_requisition.height;
    }
}

static void
gtk_viewport_size_allocate (GtkWidget     *widget,
			    GtkAllocation *allocation)
{
  GtkViewport *viewport;
  GtkBin *bin;
  GtkAllocation child_allocation;
  gint hval, vval;
  gint border_width;

  g_return_if_fail (widget != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (widget));
  g_return_if_fail (allocation != NULL);

  widget->allocation = *allocation;
  viewport = GTK_VIEWPORT (widget);
  bin = GTK_BIN (widget);

  border_width = GTK_CONTAINER (widget)->border_width;

  child_allocation.x = 0;
  child_allocation.y = 0;

  if (viewport->shadow_type != GTK_SHADOW_NONE)
    {
      child_allocation.x = GTK_WIDGET (viewport)->style->klass->xthickness;
      child_allocation.y = GTK_WIDGET (viewport)->style->klass->ythickness;
    }

  child_allocation.width = MAX (1, allocation->width - child_allocation.x * 2 - border_width * 2);
  child_allocation.height = MAX (1, allocation->height - child_allocation.y * 2 - border_width * 2);

  if (GTK_WIDGET_REALIZED (widget))
    {
      gdk_window_move_resize (widget->window,
			      allocation->x + border_width,
			      allocation->y + border_width,
			      allocation->width - border_width * 2,
			      allocation->height - border_width * 2);

      gdk_window_move_resize (viewport->view_window,
			      child_allocation.x,
			      child_allocation.y,
			      child_allocation.width,
			      child_allocation.height);
    }

  viewport->hadjustment->page_size = child_allocation.width;
  viewport->hadjustment->page_increment = viewport->hadjustment->page_size / 2;
  viewport->hadjustment->step_increment = 10;

  viewport->vadjustment->page_size = child_allocation.height;
  viewport->vadjustment->page_increment = viewport->vadjustment->page_size / 2;
  viewport->vadjustment->step_increment = 10;

  hval = viewport->hadjustment->value;
  vval = viewport->vadjustment->value;

  if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
    {
      GtkRequisition child_requisition;
      gtk_widget_get_child_requisition (bin->child, &child_requisition);
      
      viewport->hadjustment->lower = 0;
      viewport->hadjustment->upper = MAX (child_requisition.width,
					  child_allocation.width);

      hval = CLAMP (hval, 0,
		    viewport->hadjustment->upper -
		    viewport->hadjustment->page_size);

      viewport->vadjustment->lower = 0;
      viewport->vadjustment->upper = MAX (child_requisition.height,
					  child_allocation.height);

      vval = CLAMP (vval, 0,
		    viewport->vadjustment->upper -
		    viewport->vadjustment->page_size);
    }

  if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
    {
      child_allocation.x = 0;
      child_allocation.y = 0;

      child_allocation.width = viewport->hadjustment->upper;
      child_allocation.height = viewport->vadjustment->upper;

      if (!GTK_WIDGET_REALIZED (widget))
        gtk_widget_realize (widget);

      gdk_window_resize (viewport->bin_window,
			 child_allocation.width,
			 child_allocation.height);

      child_allocation.x = 0;
      child_allocation.y = 0;
      gtk_widget_size_allocate (bin->child, &child_allocation);
    }

  gtk_signal_emit_by_name (GTK_OBJECT (viewport->hadjustment), "changed");
  gtk_signal_emit_by_name (GTK_OBJECT (viewport->vadjustment), "changed");
  if (viewport->hadjustment->value != hval)
    {
      viewport->hadjustment->value = hval;
      gtk_signal_emit_by_name (GTK_OBJECT (viewport->hadjustment), "value_changed");
    }
  if (viewport->vadjustment->value != vval)
    {
      viewport->vadjustment->value = vval;
      gtk_signal_emit_by_name (GTK_OBJECT (viewport->vadjustment), "value_changed");
    }
}

static void
gtk_viewport_adjustment_changed (GtkAdjustment *adjustment,
				 gpointer       data)
{
  GtkViewport *viewport;

  g_return_if_fail (adjustment != NULL);
  g_return_if_fail (data != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (data));

  viewport = GTK_VIEWPORT (data);
}

static void
gtk_viewport_adjustment_value_changed (GtkAdjustment *adjustment,
				       gpointer       data)
{
  GtkViewport *viewport;
  GtkBin *bin;
  GtkAllocation child_allocation;
  gint width, height;

  g_return_if_fail (adjustment != NULL);
  g_return_if_fail (data != NULL);
  g_return_if_fail (GTK_IS_VIEWPORT (data));

  viewport = GTK_VIEWPORT (data);
  bin = GTK_BIN (data);

  if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
    {
      gdk_window_get_size (viewport->view_window, &width, &height);

      child_allocation.x = 0;
      child_allocation.y = 0;

      if (viewport->hadjustment->lower != (viewport->hadjustment->upper -
					   viewport->hadjustment->page_size))
	child_allocation.x =  viewport->hadjustment->lower - viewport->hadjustment->value;

      if (viewport->vadjustment->lower != (viewport->vadjustment->upper -
					   viewport->vadjustment->page_size))
	child_allocation.y = viewport->vadjustment->lower - viewport->vadjustment->value;

      if (GTK_WIDGET_REALIZED (viewport))
	gdk_window_move (viewport->bin_window,
			 child_allocation.x,
			 child_allocation.y);
    }
}

static void
gtk_viewport_style_set (GtkWidget *widget,
			GtkStyle  *previous_style)
{
   GtkViewport *viewport;
   
   if (GTK_WIDGET_REALIZED (widget) &&
       !GTK_WIDGET_NO_WINDOW (widget))
     {
	viewport = GTK_VIEWPORT (widget);
	
	gtk_style_set_background (widget->style, viewport->bin_window, GTK_STATE_NORMAL);
	gtk_style_set_background (widget->style, widget->window, widget->state);
     }
}