Pileus Git - ~andy/gtk/blob - gtk/gtkalignment.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the Free
  16  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18 #include "gtkalignment.h"
  19
  20
  21 static void gtk_alignment_class_init    (GtkAlignmentClass *klass);
  22 static void gtk_alignment_init          (GtkAlignment      *alignment);
  23 static void gtk_alignment_size_request  (GtkWidget         *widget,
  24                                          GtkRequisition    *requisition);
  25 static void gtk_alignment_size_allocate (GtkWidget         *widget,
  26                                          GtkAllocation     *allocation);
  27
  28
  29 guint
  30 gtk_alignment_get_type ()
  31 {
  32   static guint alignment_type = 0;
  33
  34   if (!alignment_type)
  35     {
  36       GtkTypeInfo alignment_info =
  37       {
  38         "GtkAlignment",
  39         sizeof (GtkAlignment),
  40         sizeof (GtkAlignmentClass),
  41         (GtkClassInitFunc) gtk_alignment_class_init,
  42         (GtkObjectInitFunc) gtk_alignment_init,
  43         (GtkArgFunc) NULL,
  44       };
  45
  46       alignment_type = gtk_type_unique (gtk_bin_get_type (), &alignment_info);
  47     }
  48
  49   return alignment_type;
  50 }
  51
  52 static void
  53 gtk_alignment_class_init (GtkAlignmentClass *class)
  54 {
  55   GtkWidgetClass *widget_class;
  56
  57   widget_class = (GtkWidgetClass*) class;
  58
  59   widget_class->size_request = gtk_alignment_size_request;
  60   widget_class->size_allocate = gtk_alignment_size_allocate;
  61 }
  62
  63 static void
  64 gtk_alignment_init (GtkAlignment *alignment)
  65 {
  66   GTK_WIDGET_SET_FLAGS (alignment, GTK_NO_WINDOW | GTK_BASIC);
  67
  68   alignment->xalign = 0.5;
  69   alignment->yalign = 0.5;
  70   alignment->xscale = 1.0;
  71   alignment->yscale = 1.0;
  72 }
  73
  74 GtkWidget*
  75 gtk_alignment_new (gfloat xalign,
  76                    gfloat yalign,
  77                    gfloat xscale,
  78                    gfloat yscale)
  79 {
  80   GtkAlignment *alignment;
  81
  82   alignment = gtk_type_new (gtk_alignment_get_type ());
  83
  84   alignment->xalign = CLAMP (xalign, 0.0, 1.0);
  85   alignment->yalign = CLAMP (yalign, 0.0, 1.0);
  86   alignment->xscale = CLAMP (xscale, 0.0, 1.0);
  87   alignment->yscale = CLAMP (yscale, 0.0, 1.0);
  88
  89   return GTK_WIDGET (alignment);
  90 }
  91
  92 void
  93 gtk_alignment_set (GtkAlignment *alignment,
  94                    gfloat        xalign,
  95                    gfloat        yalign,
  96                    gfloat        xscale,
  97                    gfloat        yscale)
  98 {
  99   g_return_if_fail (alignment != NULL);
 100   g_return_if_fail (GTK_IS_ALIGNMENT (alignment));
 101
 102   xalign = CLAMP (xalign, 0.0, 1.0);
 103   yalign = CLAMP (yalign, 0.0, 1.0);
 104   xscale = CLAMP (xscale, 0.0, 1.0);
 105   yscale = CLAMP (yscale, 0.0, 1.0);
 106
 107   if ((alignment->xalign != xalign) ||
 108       (alignment->yalign != yalign) ||
 109       (alignment->xscale != xscale) ||
 110       (alignment->yscale != yscale))
 111     {
 112       alignment->xalign = xalign;
 113       alignment->yalign = yalign;
 114       alignment->xscale = xscale;
 115       alignment->yscale = yscale;
 116
 117       gtk_widget_size_allocate (GTK_WIDGET (alignment), &(GTK_WIDGET (alignment)->allocation));
 118       gtk_widget_queue_draw (GTK_WIDGET (alignment));
 119     }
 120 }
 121
 122
 123 static void
 124 gtk_alignment_size_request (GtkWidget      *widget,
 125                             GtkRequisition *requisition)
 126 {
 127   GtkAlignment *alignment;
 128   GtkBin *bin;
 129
 130   g_return_if_fail (widget != NULL);
 131   g_return_if_fail (GTK_IS_ALIGNMENT (widget));
 132   g_return_if_fail (requisition != NULL);
 133
 134   alignment = GTK_ALIGNMENT (widget);
 135   bin = GTK_BIN (widget);
 136
 137   requisition->width = GTK_CONTAINER (widget)->border_width * 2;
 138   requisition->height = GTK_CONTAINER (widget)->border_width * 2;
 139
 140   if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
 141     {
 142       gtk_widget_size_request (bin->child, &bin->child->requisition);
 143
 144       requisition->width += bin->child->requisition.width;
 145       requisition->height += bin->child->requisition.height;
 146     }
 147 }
 148
 149 static void
 150 gtk_alignment_size_allocate (GtkWidget     *widget,
 151                              GtkAllocation *allocation)
 152 {
 153   GtkAlignment *alignment;
 154   GtkBin *bin;
 155   GtkAllocation child_allocation;
 156   gint width, height;
 157   gint x, y;
 158
 159   g_return_if_fail (widget != NULL);
 160   g_return_if_fail (GTK_IS_ALIGNMENT (widget));
 161   g_return_if_fail (allocation != NULL);
 162
 163   widget->allocation = *allocation;
 164   alignment = GTK_ALIGNMENT (widget);
 165   bin = GTK_BIN (widget);
 166
 167   if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
 168     {
 169       x = GTK_CONTAINER (alignment)->border_width;
 170       y = GTK_CONTAINER (alignment)->border_width;
 171       width = allocation->width - 2 * x;
 172       height = allocation->height - 2 * y;
 173
 174       if (width > bin->child->requisition.width)
 175         child_allocation.width = (bin->child->requisition.width *
 176                                   (1.0 - alignment->xscale) +
 177                                   width * alignment->xscale);
 178       else
 179         child_allocation.width = width;
 180
 181       if (height > bin->child->requisition.height)
 182         child_allocation.height = (bin->child->requisition.height *
 183                                   (1.0 - alignment->yscale) +
 184                                   height * alignment->yscale);
 185       else
 186         child_allocation.height = height;
 187
 188       child_allocation.x = alignment->xalign * (width - child_allocation.width) + allocation->x + x;
 189       child_allocation.y = alignment->yalign * (height - child_allocation.height) + allocation->y + y;
 190
 191       gtk_widget_size_allocate (bin->child, &child_allocation);
 192     }
 193 }