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
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GTK+ Team and others 1997-1999.  See the AUTHORS
  22  * file for a list of people on the GTK+ Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #include "gtkalignment.h"
  28
  29
  30 enum {
  31   ARG_0,
  32   ARG_XALIGN,
  33   ARG_YALIGN,
  34   ARG_XSCALE,
  35   ARG_YSCALE
  36 };
  37
  38
  39 static void gtk_alignment_class_init    (GtkAlignmentClass *klass);
  40 static void gtk_alignment_init          (GtkAlignment      *alignment);
  41 static void gtk_alignment_size_request  (GtkWidget         *widget,
  42                                          GtkRequisition    *requisition);
  43 static void gtk_alignment_size_allocate (GtkWidget         *widget,
  44                                          GtkAllocation     *allocation);
  45 static void gtk_alignment_set_arg       (GtkObject         *object,
  46                                          GtkArg            *arg,
  47                                          guint              arg_id);
  48 static void gtk_alignment_get_arg       (GtkObject         *object,
  49                                          GtkArg            *arg,
  50                                          guint              arg_id);
  51
  52
  53
  54 GtkType
  55 gtk_alignment_get_type (void)
  56 {
  57   static GtkType alignment_type = 0;
  58
  59   if (!alignment_type)
  60     {
  61       static const GtkTypeInfo alignment_info =
  62       {
  63         "GtkAlignment",
  64         sizeof (GtkAlignment),
  65         sizeof (GtkAlignmentClass),
  66         (GtkClassInitFunc) gtk_alignment_class_init,
  67         (GtkObjectInitFunc) gtk_alignment_init,
  68         /* reserved_1 */ NULL,
  69         /* reserved_2 */ NULL,
  70         (GtkClassInitFunc) NULL,
  71       };
  72
  73       alignment_type = gtk_type_unique (GTK_TYPE_BIN, &alignment_info);
  74     }
  75
  76   return alignment_type;
  77 }
  78
  79 static void
  80 gtk_alignment_class_init (GtkAlignmentClass *class)
  81 {
  82   GtkObjectClass *object_class;
  83   GtkWidgetClass *widget_class;
  84
  85   object_class = (GtkObjectClass*) class;
  86   widget_class = (GtkWidgetClass*) class;
  87
  88   gtk_object_add_arg_type ("GtkAlignment::xalign", GTK_TYPE_FLOAT, GTK_ARG_READWRITE, ARG_XALIGN);
  89   gtk_object_add_arg_type ("GtkAlignment::yalign", GTK_TYPE_FLOAT, GTK_ARG_READWRITE, ARG_YALIGN);
  90   gtk_object_add_arg_type ("GtkAlignment::xscale", GTK_TYPE_FLOAT, GTK_ARG_READWRITE, ARG_XSCALE);
  91   gtk_object_add_arg_type ("GtkAlignment::yscale", GTK_TYPE_FLOAT, GTK_ARG_READWRITE, ARG_YSCALE);
  92
  93   object_class->set_arg = gtk_alignment_set_arg;
  94   object_class->get_arg = gtk_alignment_get_arg;
  95
  96   widget_class->size_request = gtk_alignment_size_request;
  97   widget_class->size_allocate = gtk_alignment_size_allocate;
  98 }
  99
 100 static void
 101 gtk_alignment_init (GtkAlignment *alignment)
 102 {
 103   GTK_WIDGET_SET_FLAGS (alignment, GTK_NO_WINDOW);
 104
 105   alignment->xalign = 0.5;
 106   alignment->yalign = 0.5;
 107   alignment->xscale = 1.0;
 108   alignment->yscale = 1.0;
 109 }
 110
 111 GtkWidget*
 112 gtk_alignment_new (gfloat xalign,
 113                    gfloat yalign,
 114                    gfloat xscale,
 115                    gfloat yscale)
 116 {
 117   GtkAlignment *alignment;
 118
 119   alignment = gtk_type_new (gtk_alignment_get_type ());
 120
 121   alignment->xalign = CLAMP (xalign, 0.0, 1.0);
 122   alignment->yalign = CLAMP (yalign, 0.0, 1.0);
 123   alignment->xscale = CLAMP (xscale, 0.0, 1.0);
 124   alignment->yscale = CLAMP (yscale, 0.0, 1.0);
 125
 126   return GTK_WIDGET (alignment);
 127 }
 128
 129 static void
 130 gtk_alignment_set_arg (GtkObject         *object,
 131                        GtkArg            *arg,
 132                        guint              arg_id)
 133 {
 134   GtkAlignment *alignment;
 135
 136   alignment = GTK_ALIGNMENT (object);
 137
 138   switch (arg_id)
 139     {
 140     case ARG_XALIGN:
 141       gtk_alignment_set (alignment,
 142                          GTK_VALUE_FLOAT (*arg),
 143                          alignment->yalign,
 144                          alignment->xscale,
 145                          alignment->yscale);
 146       break;
 147     case ARG_YALIGN:
 148       gtk_alignment_set (alignment,
 149                          alignment->xalign,
 150                          GTK_VALUE_FLOAT (*arg),
 151                          alignment->xscale,
 152                          alignment->yscale);
 153       break;
 154     case ARG_XSCALE:
 155       gtk_alignment_set (alignment,
 156                          alignment->xalign,
 157                          alignment->yalign,
 158                          GTK_VALUE_FLOAT (*arg),
 159                          alignment->yscale);
 160       break;
 161     case ARG_YSCALE:
 162       gtk_alignment_set (alignment,
 163                          alignment->xalign,
 164                          alignment->yalign,
 165                          alignment->xscale,
 166                          GTK_VALUE_FLOAT (*arg));
 167       break;
 168     default:
 169       break;
 170     }
 171 }
 172
 173 static void
 174 gtk_alignment_get_arg (GtkObject         *object,
 175                        GtkArg            *arg,
 176                        guint              arg_id)
 177 {
 178   GtkAlignment *alignment;
 179
 180   alignment = GTK_ALIGNMENT (object);
 181
 182   switch (arg_id)
 183     {
 184     case ARG_XALIGN:
 185       GTK_VALUE_FLOAT (*arg) = alignment->xalign;
 186       break;
 187     case ARG_YALIGN:
 188       GTK_VALUE_FLOAT (*arg) = alignment->yalign;
 189       break;
 190     case ARG_XSCALE:
 191       GTK_VALUE_FLOAT (*arg) = alignment->xscale;
 192       break;
 193     case ARG_YSCALE:
 194       GTK_VALUE_FLOAT (*arg) = alignment->yscale;
 195       break;
 196     default:
 197       arg->type = GTK_TYPE_INVALID;
 198       break;
 199     }
 200 }
 201
 202 void
 203 gtk_alignment_set (GtkAlignment *alignment,
 204                    gfloat        xalign,
 205                    gfloat        yalign,
 206                    gfloat        xscale,
 207                    gfloat        yscale)
 208 {
 209   g_return_if_fail (alignment != NULL);
 210   g_return_if_fail (GTK_IS_ALIGNMENT (alignment));
 211
 212   xalign = CLAMP (xalign, 0.0, 1.0);
 213   yalign = CLAMP (yalign, 0.0, 1.0);
 214   xscale = CLAMP (xscale, 0.0, 1.0);
 215   yscale = CLAMP (yscale, 0.0, 1.0);
 216
 217   if ((alignment->xalign != xalign) ||
 218       (alignment->yalign != yalign) ||
 219       (alignment->xscale != xscale) ||
 220       (alignment->yscale != yscale))
 221     {
 222       alignment->xalign = xalign;
 223       alignment->yalign = yalign;
 224       alignment->xscale = xscale;
 225       alignment->yscale = yscale;
 226
 227       gtk_widget_size_allocate (GTK_WIDGET (alignment), &(GTK_WIDGET (alignment)->allocation));
 228       gtk_widget_queue_draw (GTK_WIDGET (alignment));
 229     }
 230 }
 231
 232
 233 static void
 234 gtk_alignment_size_request (GtkWidget      *widget,
 235                             GtkRequisition *requisition)
 236 {
 237   GtkAlignment *alignment;
 238   GtkBin *bin;
 239
 240   g_return_if_fail (widget != NULL);
 241   g_return_if_fail (GTK_IS_ALIGNMENT (widget));
 242   g_return_if_fail (requisition != NULL);
 243
 244   alignment = GTK_ALIGNMENT (widget);
 245   bin = GTK_BIN (widget);
 246
 247   requisition->width = GTK_CONTAINER (widget)->border_width * 2;
 248   requisition->height = GTK_CONTAINER (widget)->border_width * 2;
 249
 250   if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
 251     {
 252       GtkRequisition child_requisition;
 253
 254       gtk_widget_size_request (bin->child, &child_requisition);
 255
 256       requisition->width += child_requisition.width;
 257       requisition->height += child_requisition.height;
 258     }
 259 }
 260
 261 static void
 262 gtk_alignment_size_allocate (GtkWidget     *widget,
 263                              GtkAllocation *allocation)
 264 {
 265   GtkAlignment *alignment;
 266   GtkBin *bin;
 267   GtkAllocation child_allocation;
 268   GtkRequisition child_requisition;
 269   gint width, height;
 270   gint x, y;
 271
 272   g_return_if_fail (widget != NULL);
 273   g_return_if_fail (GTK_IS_ALIGNMENT (widget));
 274   g_return_if_fail (allocation != NULL);
 275
 276   widget->allocation = *allocation;
 277   alignment = GTK_ALIGNMENT (widget);
 278   bin = GTK_BIN (widget);
 279
 280   if (bin->child && GTK_WIDGET_VISIBLE (bin->child))
 281     {
 282       gtk_widget_get_child_requisition (bin->child, &child_requisition);
 283
 284       x = GTK_CONTAINER (alignment)->border_width;
 285       y = GTK_CONTAINER (alignment)->border_width;
 286       width = MAX (allocation->width - 2 * x, 0);
 287       height = MAX (allocation->height - 2 * y, 0);
 288
 289       if (width > child_requisition.width)
 290         child_allocation.width = (child_requisition.width *
 291                                   (1.0 - alignment->xscale) +
 292                                   width * alignment->xscale);
 293       else
 294         child_allocation.width = width;
 295
 296       if (height > child_requisition.height)
 297         child_allocation.height = (child_requisition.height *
 298                                    (1.0 - alignment->yscale) +
 299                                    height * alignment->yscale);
 300       else
 301         child_allocation.height = height;
 302
 303       child_allocation.x = alignment->xalign * (width - child_allocation.width) + allocation->x + x;
 304       child_allocation.y = alignment->yalign * (height - child_allocation.height) + allocation->y + y;
 305
 306       gtk_widget_size_allocate (bin->child, &child_allocation);
 307     }
 308 }