src/gtk/gtkvscrollbutton.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 3 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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * Modified by the GTK+ Team and others 1997-1999.  See the AUTHORS
  20  * file for a list of people on the GTK+ Team.  See the ChangeLog
  21  * files for a list of changes.  These files are distributed with
  22  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  23  */
  24
  25  /*
  26   * Simple composite widget to provide vertical scrolling, based
  27   * on GtkRange widget code.
  28   * Modified by the Sylpheed Team and others 2003
  29   */
  30
  31 #ifdef HAVE_CONFIG_H
  32 #  include "config.h"
  33 #include "claws-features.h"
  34 #endif
  35
  36 #include <glib.h>
  37 #include <gtk/gtk.h>
  38 #include "utils.h"
  39 #include "gtkvscrollbutton.h"
  40 #include "gtkutils.h"
  41
  42 #define SCROLL_TIMER_LENGTH  20
  43 #define SCROLL_INITIAL_DELAY 100        /* must hold button this long before ... */
  44 #define SCROLL_LATER_DELAY   20 /* ... it starts repeating at this rate  */
  45 #define SCROLL_DELAY_LENGTH  300
  46
  47
  48 enum {
  49     ARG_0,
  50     ARG_ADJUSTMENT
  51 };
  52
  53 static void gtk_vscrollbutton_class_init(GtkVScrollbuttonClass * klass);
  54 static void gtk_vscrollbutton_init(GtkVScrollbutton * vscrollbutton);
  55
  56 GType gtk_vscrollbutton_get_type                (void);
  57 GtkWidget *gtk_vscrollbutton_new                (GtkAdjustment    *adjustment);
  58
  59 static gint gtk_vscrollbutton_button_release    (GtkWidget        *widget,
  60                                                  GdkEventButton   *event,
  61                                                  GtkVScrollbutton *scrollbutton);
  62
  63 static void gtk_vscrollbutton_set_adjustment    (GtkVScrollbutton *scrollbutton,
  64                                                  GtkAdjustment    *adjustment);
  65
  66 static gint gtk_vscrollbutton_button_press      (GtkWidget        *widget,
  67                                                  GdkEventButton   *event,
  68                                                  GtkVScrollbutton *scrollbutton);
  69
  70 static gint gtk_vscrollbutton_button_release    (GtkWidget        *widget,
  71                                                  GdkEventButton   *event,
  72                                                  GtkVScrollbutton *scrollbutton);
  73
  74 gint gtk_vscrollbutton_scroll           (GtkVScrollbutton *scrollbutton);
  75
  76 static gboolean gtk_vscrollbutton_timer_1st_time(GtkVScrollbutton *scrollbutton);
  77
  78 static void gtk_vscrollbutton_add_timer         (GtkVScrollbutton *scrollbutton);
  79
  80 static void gtk_vscrollbutton_remove_timer      (GtkVScrollbutton *scrollbutton);
  81
  82 static gboolean gtk_real_vscrollbutton_timer    (GtkVScrollbutton *scrollbutton);
  83
  84 static void gtk_vscrollbutton_set_sensitivity   (GtkAdjustment    *adjustment,
  85                                                  GtkVScrollbutton *scrollbutton);
  86
  87 GType gtk_vscrollbutton_get_type(void)
  88 {
  89     static GType vscrollbutton_type = 0;
  90
  91     if (!vscrollbutton_type) {
  92         static const GTypeInfo vscrollbutton_info = {
  93                         sizeof (GtkVScrollbuttonClass),
  94
  95                         (GBaseInitFunc) NULL,
  96                         (GBaseFinalizeFunc) NULL,
  97
  98                         (GClassInitFunc) gtk_vscrollbutton_class_init,
  99                         (GClassFinalizeFunc) NULL,
 100                         NULL,   /* class_data */
 101
 102                         sizeof (GtkVScrollbutton),
 103                         0,      /* n_preallocs */
 104                         (GInstanceInitFunc) gtk_vscrollbutton_init,
 105         };
 106
 107         vscrollbutton_type = g_type_register_static (GTK_TYPE_VBOX, "GtkVScrollbutton", &vscrollbutton_info, (GTypeFlags)0);
 108     }
 109
 110     return vscrollbutton_type;
 111 }
 112
 113 static void gtk_vscrollbutton_class_init(GtkVScrollbuttonClass *class)
 114 {
 115 }
 116
 117 static GdkCursor *hand_cursor = NULL;
 118
 119 static gboolean vscroll_visi_notify(GtkWidget *widget,
 120                                        GdkEventVisibility *event,
 121                                        gpointer data)
 122 {
 123         gdk_window_set_cursor(gtk_widget_get_window(widget), hand_cursor);
 124         return FALSE;
 125 }
 126
 127 static gboolean vscroll_leave_notify(GtkWidget *widget,
 128                                       GdkEventCrossing *event,
 129                                        gpointer data)
 130 {
 131         gdk_window_set_cursor(gtk_widget_get_window(widget), NULL);
 132         return FALSE;
 133 }
 134
 135 static gboolean vscroll_enter_notify(GtkWidget *widget,
 136                                       GdkEventCrossing *event,
 137                                        gpointer data)
 138 {
 139         gdk_window_set_cursor(gtk_widget_get_window(widget), hand_cursor);
 140         return FALSE;
 141 }
 142
 143
 144 static void gtk_vscrollbutton_init(GtkVScrollbutton *scrollbutton)
 145 {
 146     GtkWidget *arrow;
 147
 148     if (!hand_cursor)
 149             hand_cursor = gdk_cursor_new(GDK_HAND2);
 150
 151     scrollbutton->upbutton = gtk_event_box_new();
 152     scrollbutton->downbutton = gtk_event_box_new();
 153     arrow = gtk_arrow_new(GTK_ARROW_UP, GTK_SHADOW_NONE);
 154     gtk_widget_show(arrow);
 155     gtk_container_add(GTK_CONTAINER(scrollbutton->upbutton), arrow);
 156     gtk_widget_set_size_request(scrollbutton->upbutton, -1, 16);
 157     arrow = gtk_arrow_new(GTK_ARROW_DOWN, GTK_SHADOW_NONE);
 158     gtk_widget_show(arrow);
 159     gtk_container_add(GTK_CONTAINER(scrollbutton->downbutton), arrow);
 160     gtk_widget_set_size_request(scrollbutton->downbutton, -1, 16);
 161     gtkut_widget_set_can_focus(scrollbutton->upbutton, FALSE);
 162     gtkut_widget_set_can_focus(scrollbutton->downbutton, FALSE);
 163     gtk_widget_show(scrollbutton->downbutton);
 164     gtk_widget_show(scrollbutton->upbutton);
 165
 166     g_signal_connect(G_OBJECT(scrollbutton->upbutton), "motion-notify-event",
 167                      G_CALLBACK(vscroll_visi_notify), NULL);
 168     g_signal_connect(G_OBJECT(scrollbutton->upbutton), "leave-notify-event",
 169                      G_CALLBACK(vscroll_leave_notify), NULL);
 170     g_signal_connect(G_OBJECT(scrollbutton->upbutton), "enter-notify-event",
 171                      G_CALLBACK(vscroll_enter_notify), NULL);
 172     g_signal_connect(G_OBJECT(scrollbutton->downbutton), "motion-notify-event",
 173                      G_CALLBACK(vscroll_visi_notify), NULL);
 174     g_signal_connect(G_OBJECT(scrollbutton->downbutton), "leave-notify-event",
 175                      G_CALLBACK(vscroll_leave_notify), NULL);
 176     g_signal_connect(G_OBJECT(scrollbutton->downbutton), "enter-notify-event",
 177                      G_CALLBACK(vscroll_enter_notify), NULL);
 178
 179     g_signal_connect(G_OBJECT(scrollbutton->upbutton),
 180                        "button_press_event",
 181                        G_CALLBACK(gtk_vscrollbutton_button_press),
 182                        scrollbutton);
 183     g_signal_connect(G_OBJECT(scrollbutton->downbutton),
 184                        "button_press_event",
 185                        G_CALLBACK(gtk_vscrollbutton_button_press),
 186                        scrollbutton);
 187     g_signal_connect(G_OBJECT(scrollbutton->upbutton),
 188                      "button_release_event",
 189                      G_CALLBACK
 190                      (gtk_vscrollbutton_button_release), scrollbutton);
 191     g_signal_connect(G_OBJECT(scrollbutton->downbutton),
 192                      "button_release_event",
 193                      G_CALLBACK
 194                      (gtk_vscrollbutton_button_release), scrollbutton);
 195     gtk_box_pack_start(GTK_BOX(&scrollbutton->vbox),
 196                        scrollbutton->upbutton, TRUE, TRUE, 0);
 197     gtk_box_pack_end(GTK_BOX(&scrollbutton->vbox),
 198                      scrollbutton->downbutton, TRUE, TRUE, 0);
 199     scrollbutton->timer = 0;
 200 }
 201
 202 GtkWidget *gtk_vscrollbutton_new(GtkAdjustment *adjustment)
 203 {
 204     GtkWidget *vscrollbutton;
 205     vscrollbutton = g_object_new (gtk_vscrollbutton_get_type(),
 206                         NULL);
 207     gtk_vscrollbutton_set_adjustment(GTK_VSCROLLBUTTON(vscrollbutton),
 208                                      adjustment);
 209     g_signal_connect(G_OBJECT(GTK_VSCROLLBUTTON(vscrollbutton)->adjustment),
 210                        "value_changed",
 211                        G_CALLBACK
 212                        (gtk_vscrollbutton_set_sensitivity), vscrollbutton);
 213     g_signal_connect(G_OBJECT(GTK_VSCROLLBUTTON(vscrollbutton)->adjustment),
 214                        "changed",
 215                        G_CALLBACK
 216                        (gtk_vscrollbutton_set_sensitivity), vscrollbutton);
 217     return vscrollbutton;
 218 }
 219
 220
 221 void gtk_vscrollbutton_set_adjustment(GtkVScrollbutton *scrollbutton,
 222                                       GtkAdjustment *adjustment)
 223 {
 224     cm_return_if_fail(scrollbutton != NULL);
 225     cm_return_if_fail(GTK_IS_VSCROLLBUTTON(scrollbutton));
 226
 227     if (!adjustment)
 228             adjustment =
 229             GTK_ADJUSTMENT(gtk_adjustment_new(0.0, 0.0, 0.0, 0.0, 0.0, 0.0));
 230     else
 231         cm_return_if_fail(GTK_IS_ADJUSTMENT(adjustment));
 232
 233     if (scrollbutton->adjustment != adjustment) {
 234         if (scrollbutton->adjustment) {
 235             g_signal_handlers_disconnect_matched(scrollbutton->adjustment,
 236                                                  G_SIGNAL_MATCH_DATA,
 237                                                  0, 0, NULL, NULL,
 238                                                  (gpointer) scrollbutton);
 239             g_object_unref(G_OBJECT(scrollbutton->adjustment));
 240         }
 241
 242         scrollbutton->adjustment = adjustment;
 243         g_object_ref(G_OBJECT(adjustment));
 244 #if GLIB_CHECK_VERSION(2,10,0)
 245         g_object_ref_sink (G_OBJECT(adjustment));
 246 #else
 247         gtk_object_ref (G_OBJECT (adjustment));
 248         gtk_object_sink (G_OBJECT (adjustment));
 249 #endif
 250     }
 251 }
 252
 253 static gint gtk_vscrollbutton_button_press(GtkWidget *widget,
 254                                            GdkEventButton *event,
 255                                            GtkVScrollbutton *scrollbutton)
 256 {
 257     if (!gtk_widget_has_focus(widget))
 258         gtk_widget_grab_focus(widget);
 259
 260     if (scrollbutton->button == 0) {
 261         gtk_grab_add(widget);
 262         scrollbutton->button = event->button;
 263
 264         if (widget == scrollbutton->downbutton)
 265             scrollbutton->scroll_type = GTK_SCROLL_STEP_FORWARD;
 266         else
 267             scrollbutton->scroll_type = GTK_SCROLL_STEP_BACKWARD;
 268         gtk_vscrollbutton_scroll(scrollbutton);
 269         gtk_vscrollbutton_add_timer(scrollbutton);
 270     }
 271     return TRUE;
 272 }
 273
 274
 275 static gint gtk_vscrollbutton_button_release(GtkWidget *widget,
 276                                              GdkEventButton *event,
 277                                              GtkVScrollbutton *scrollbutton)
 278 {
 279     if (!gtk_widget_has_focus(widget))
 280         gtk_widget_grab_focus(widget);
 281
 282     if (scrollbutton->button == event->button) {
 283         gtk_grab_remove(widget);
 284
 285         scrollbutton->button = 0;
 286         gtk_vscrollbutton_remove_timer(scrollbutton);
 287         gtk_vscrollbutton_set_sensitivity(scrollbutton->adjustment, scrollbutton);
 288     }
 289     return TRUE;
 290 }
 291
 292 gboolean gtk_vscrollbutton_scroll(GtkVScrollbutton *scrollbutton)
 293 {
 294     gfloat bound;
 295     gfloat new_value;
 296     gfloat page_size;
 297     gfloat value;
 298     gboolean return_val;
 299
 300     cm_return_val_if_fail(scrollbutton != NULL, FALSE);
 301     cm_return_val_if_fail(GTK_IS_VSCROLLBUTTON(scrollbutton), FALSE);
 302
 303     new_value = value = gtk_adjustment_get_value(scrollbutton->adjustment);
 304     return_val = TRUE;
 305
 306     switch (scrollbutton->scroll_type) {
 307
 308     case GTK_SCROLL_STEP_BACKWARD:
 309         new_value = value - gtk_adjustment_get_step_increment(scrollbutton->adjustment);
 310         bound = gtk_adjustment_get_lower(scrollbutton->adjustment);
 311         if (new_value <= bound) {
 312             new_value = bound;
 313             return_val = FALSE;
 314             scrollbutton->timer = 0;
 315         }
 316         break;
 317
 318     case GTK_SCROLL_STEP_FORWARD:
 319         new_value = value + gtk_adjustment_get_step_increment(scrollbutton->adjustment);
 320         bound = gtk_adjustment_get_upper(scrollbutton->adjustment);
 321         page_size = gtk_adjustment_get_page_size(scrollbutton->adjustment);
 322         if (new_value >= (bound - page_size)) {
 323             new_value = bound - page_size;
 324             return_val = FALSE;
 325             scrollbutton->timer = 0;
 326         }
 327         break;
 328
 329     default:
 330         break;
 331
 332     }
 333
 334         if (new_value != value) {
 335         gtk_adjustment_set_value(scrollbutton->adjustment, new_value);
 336         g_signal_emit_by_name(G_OBJECT
 337                                 (scrollbutton->adjustment),
 338                                 "value_changed");
 339         gtk_widget_queue_resize(GTK_WIDGET(scrollbutton)); /* ensure resize */
 340     }
 341
 342     return return_val;
 343 }
 344
 345 static gboolean
 346 gtk_vscrollbutton_timer_1st_time(GtkVScrollbutton *scrollbutton)
 347 {
 348     /*
 349      * If the real timeout function succeeds and the timeout is still set,
 350      * replace it with a quicker one so successive scrolling goes faster.
 351      */
 352     g_object_ref(G_OBJECT(scrollbutton));
 353     if (scrollbutton->timer) {
 354         /* We explicitely remove ourselves here in the paranoia
 355          * that due to things happening above in the callback
 356          * above, we might have been removed, and another added.
 357          */
 358         g_source_remove(scrollbutton->timer);
 359         scrollbutton->timer = g_timeout_add(SCROLL_LATER_DELAY,
 360                                             (GSourceFunc)
 361                                             gtk_real_vscrollbutton_timer,
 362                                             scrollbutton);
 363     }
 364     g_object_unref(G_OBJECT(scrollbutton));
 365     return FALSE;               /* don't keep calling this function */
 366 }
 367
 368
 369 static void gtk_vscrollbutton_add_timer(GtkVScrollbutton *scrollbutton)
 370 {
 371     cm_return_if_fail(scrollbutton != NULL);
 372     cm_return_if_fail(GTK_IS_VSCROLLBUTTON(scrollbutton));
 373
 374     if (!scrollbutton->timer) {
 375         scrollbutton->need_timer = TRUE;
 376         scrollbutton->timer = g_timeout_add(SCROLL_INITIAL_DELAY,
 377                                             (GSourceFunc)
 378                                             gtk_vscrollbutton_timer_1st_time,
 379                                             scrollbutton);
 380     }
 381 }
 382
 383 static void gtk_vscrollbutton_remove_timer(GtkVScrollbutton *scrollbutton)
 384 {
 385     cm_return_if_fail(scrollbutton != NULL);
 386     cm_return_if_fail(GTK_IS_VSCROLLBUTTON(scrollbutton));
 387
 388     if (scrollbutton->timer) {
 389         g_source_remove(scrollbutton->timer);
 390         scrollbutton->timer = 0;
 391     }
 392     scrollbutton->need_timer = FALSE;
 393 }
 394
 395 static gboolean gtk_real_vscrollbutton_timer(GtkVScrollbutton *scrollbutton)
 396 {
 397     gboolean return_val;
 398
 399     GDK_THREADS_ENTER();
 400
 401     return_val = TRUE;
 402     if (!scrollbutton->timer) {
 403         return_val = FALSE;
 404         if (scrollbutton->need_timer)
 405             scrollbutton->timer =
 406                 g_timeout_add(SCROLL_TIMER_LENGTH,
 407                               (GSourceFunc) gtk_real_vscrollbutton_timer,
 408                               (gpointer) scrollbutton);
 409         else {
 410             GDK_THREADS_LEAVE();
 411             return FALSE;
 412         }
 413         scrollbutton->need_timer = FALSE;
 414     }
 415     GDK_THREADS_LEAVE();
 416     return_val = gtk_vscrollbutton_scroll(scrollbutton);
 417     return return_val;
 418 }
 419
 420 static void gtk_vscrollbutton_set_sensitivity   (GtkAdjustment    *adjustment,
 421                                                  GtkVScrollbutton *scrollbutton)
 422 {
 423         gfloat value;
 424         if (!gtk_widget_get_realized(GTK_WIDGET(scrollbutton))) return;
 425         if (scrollbutton->button != 0) return; /* not while something is pressed */
 426
 427         value = gtk_adjustment_get_value(adjustment);
 428         gtk_widget_set_sensitive(scrollbutton->upbutton,
 429                                  (value > gtk_adjustment_get_lower(adjustment)));
 430         gtk_widget_set_sensitive(scrollbutton->downbutton,
 431                                  (value < (gtk_adjustment_get_upper(adjustment) -
 432                            gtk_adjustment_get_page_size(adjustment))));
 433 }