git.maemo.org Git - modest/blob - src/widgets/modest-validating-entry.c

   1 /* Copyright (c) 2007, Nokia Corporation
   2  * All rights reserved.
   3  *
   4  */
   5
   6 #include "modest-validating-entry.h"
   7 #include <gtk/gtksignal.h> /* For the gtk_signal_stop_emit_by_name() convenience function. */
   8 #include <string.h> /* For strlen(). */
   9
  10 /* Include config.h so that _() works: */
  11 #ifdef HAVE_CONFIG_H
  12 #include <config.h>
  13 #endif
  14
  15 G_DEFINE_TYPE (ModestValidatingEntry, modest_validating_entry, GTK_TYPE_ENTRY);
  16
  17 #define VALIDATING_ENTRY_GET_PRIVATE(o) \
  18         (G_TYPE_INSTANCE_GET_PRIVATE ((o), MODEST_TYPE_VALIDATING_ENTRY, ModestValidatingEntryPrivate))
  19
  20 typedef struct _ModestValidatingEntryPrivate ModestValidatingEntryPrivate;
  21
  22 struct _ModestValidatingEntryPrivate
  23 {
  24         /* A list of gunichar, rather than char*,
  25          * because gunichar is easier to deal with internally,
  26          * but gchar* is easier to supply from the external interface.
  27          */
  28         GList *list_prevent;
  29
  30         gboolean prevent_whitespace;
  31
  32         EasySetupValidatingEntryMaxFunc max_func;
  33         gpointer max_func_user_data;
  34 };
  35
  36 static void
  37 modest_validating_entry_get_property (GObject *object, guint property_id,
  38                                                                                                                         GValue *value, GParamSpec *pspec)
  39 {
  40         switch (property_id) {
  41         default:
  42                 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
  43         }
  44 }
  45
  46 static void
  47 modest_validating_entry_set_property (GObject *object, guint property_id,
  48                                                                                                                         const GValue *value, GParamSpec *pspec)
  49 {
  50         switch (property_id) {
  51         default:
  52                 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
  53         }
  54 }
  55
  56 static void
  57 modest_validating_entry_dispose (GObject *object)
  58 {
  59         if (G_OBJECT_CLASS (modest_validating_entry_parent_class)->dispose)
  60                 G_OBJECT_CLASS (modest_validating_entry_parent_class)->dispose (object);
  61 }
  62
  63 static void
  64 modest_validating_entry_finalize (GObject *object)
  65 {
  66         ModestValidatingEntryPrivate *priv = VALIDATING_ENTRY_GET_PRIVATE (object);
  67
  68         /* Free the list and its items: */
  69         if (priv->list_prevent) {
  70                 g_list_foreach (priv->list_prevent, (GFunc)&g_free, NULL);
  71                 g_list_free (priv->list_prevent);
  72         }
  73
  74         G_OBJECT_CLASS (modest_validating_entry_parent_class)->finalize (object);
  75 }
  76
  77 static void
  78 modest_validating_entry_class_init (ModestValidatingEntryClass *klass)
  79 {
  80         GObjectClass *object_class = G_OBJECT_CLASS (klass);
  81
  82         g_type_class_add_private (klass, sizeof (ModestValidatingEntryPrivate));
  83
  84         object_class->get_property = modest_validating_entry_get_property;
  85         object_class->set_property = modest_validating_entry_set_property;
  86         object_class->dispose = modest_validating_entry_dispose;
  87         object_class->finalize = modest_validating_entry_finalize;
  88 }
  89
  90 static gint
  91 on_list_compare(gconstpointer a, gconstpointer b)
  92 {
  93         gunichar* unichar_a = (gunichar*)(a);
  94         gunichar* unichar_b = (gunichar*)(b);
  95         if(*unichar_a == *unichar_b)
  96                 return 0;
  97         else
  98                 return -1; /* Really, we should return > and <, but we don't use this for sorting. */
  99 }
 100
 101 static void
 102 on_insert_text(GtkEditable *editable,
 103         gchar *new_text, gint new_text_length,
 104         gint *position,
 105     gpointer user_data)
 106 {
 107         ModestValidatingEntry *self = MODEST_VALIDATING_ENTRY (user_data);
 108         ModestValidatingEntryPrivate *priv = VALIDATING_ENTRY_GET_PRIVATE (self);
 109
 110         if(!new_text_length)
 111                 return;
 112
 113         /* Note: new_text_length is documented as the number of bytes, not characters. */
 114         if(!g_utf8_validate (new_text, new_text_length, NULL))
 115                 return;
 116
 117         /* Look at each UTF-8 character in the text (it could be several via a drop or a paste),
 118          * and check them */
 119         gboolean allow = TRUE;
 120         gchar *iter = new_text; /* new_text seems to be NULL-terminated, though that is not documented. */
 121         while (iter)
 122         {
 123                 if(priv->list_prevent) {
 124                         /* If the character is in our prevent list,
 125                          * then do not allow this text to be entered.
 126                          *
 127                          * This prevents entry of all text, without removing the unwanted characters.
 128                          * It is debatable whether that is the best thing to do.
 129                          */
 130                         gunichar one_char = g_utf8_get_char (iter);
 131                         GList *found = g_list_find_custom(priv->list_prevent, &one_char, &on_list_compare);
 132                         if(found) {
 133                                 allow = FALSE;
 134                                 break;
 135                         }
 136                 }
 137
 138                 if(priv->prevent_whitespace) {
 139                         /* Check for whitespace characters: */
 140                         gunichar one_char = g_utf8_get_char (iter);
 141                         if (g_unichar_isspace (one_char)) {
 142                                 allow = FALSE;
 143                                 break;
 144                         }
 145                 }
 146
 147                 /* Crashes. Don't know why: iter = g_utf8_next_char (iter);
 148                  * Maybe it doesn't check for null-termination. */
 149                 iter = g_utf8_find_next_char (iter, new_text + new_text_length);
 150         }
 151
 152         /* Prevent more than the max characters.
 153          * The regular GtkEntry does this already, but we also want to call a specified callback,
 154          * so that the application can show a warning dialog. */
 155         if(priv->max_func) {
 156                 const gint max_num = gtk_entry_get_max_length (GTK_ENTRY (self));
 157                 if (max_num > 0) {
 158                         const gchar *existing_text = gtk_entry_get_text (GTK_ENTRY(self));
 159                         const gint existing_length = existing_text ? g_utf8_strlen (existing_text, -1) : 0;
 160                         const gint new_length_chars = g_utf8_strlen (new_text, new_text_length);
 161
 162                         if ((existing_length + new_length_chars) > max_num) {
 163                                 priv->max_func (self, priv->max_func_user_data);
 164                                 /* We shouldn't need to stop the signal because the underlying code will check too.
 165                                 * Well, that would maybe be a performance optimization,
 166                                  * but it's generally safer not to interfere too much. */
 167                         }
 168                 }
 169         }
 170
 171         if(!allow) {
 172                 /* The signal documentation says
 173                  * "by connecting to this signal and then stopping the signal with
 174                  * gtk_signal_emit_stop(), it is possible to modify the inserted text,
 175                  * or prevent it from being inserted entirely."
 176                  */
 177                  gtk_signal_emit_stop_by_name (GTK_OBJECT (self), "insert-text");
 178         }
 179
 180 }
 181
 182 static void
 183 modest_validating_entry_init (ModestValidatingEntry *self)
 184 {
 185         /* Connect to the GtkEditable::insert-text signal
 186          * so we can filter out some characters:
 187          * We connect _before_ so we can stop the default signal handler from running.
 188          */
 189         g_signal_connect (G_OBJECT (self), "insert-text", (GCallback)&on_insert_text, self);
 190 }
 191
 192 ModestValidatingEntry*
 193 modest_validating_entry_new (void)
 194 {
 195         return g_object_new (MODEST_TYPE_VALIDATING_ENTRY, NULL);
 196 }
 197
 198 /** Specify characters that may not be entered into this GtkEntry.
 199  *
 200  * list: A list of gchar* strings. Each one identifies a UTF-8 character.
 201  */
 202 void modest_validating_entry_set_unallowed_characters (ModestValidatingEntry *self, GList *list)
 203 {
 204         ModestValidatingEntryPrivate *priv = VALIDATING_ENTRY_GET_PRIVATE (self);
 205
 206         /* Free the list and its items: */
 207         if (priv->list_prevent) {
 208                 g_list_foreach (priv->list_prevent, (GFunc)&g_free, NULL);
 209                 g_list_free (priv->list_prevent);
 210         }
 211
 212     /* Do a deep copy of the list, converting gchar* to gunichar: */
 213     priv->list_prevent = NULL;
 214     GList *iter = NULL;
 215     for (iter = list; iter != NULL; iter = iter->next) {
 216         gunichar *one_char = g_new0 (gunichar, 1);
 217         if(iter->data)
 218                 *one_char = g_utf8_get_char ((gchar*)iter->data);
 219         else
 220                 *one_char = 0;
 221
 222         priv->list_prevent = g_list_append (priv->list_prevent, one_char);
 223     }
 224 }
 225
 226 /** Specify that no whitespace characters may be entered into this GtkEntry.
 227  *
 228  */
 229 void modest_validating_entry_set_unallowed_characters_whitespace (ModestValidatingEntry *self)
 230 {
 231         ModestValidatingEntryPrivate *priv = VALIDATING_ENTRY_GET_PRIVATE (self);
 232         priv->prevent_whitespace = TRUE;
 233 }
 234
 235 /** Set a callback to be called when the maximum number of characters have been entered.
 236  * This may be used to show an informative dialog.
 237  */
 238 void modest_validating_entry_set_max_func (ModestValidatingEntry *self, EasySetupValidatingEntryMaxFunc func, gpointer user_data)
 239 {
 240         ModestValidatingEntryPrivate *priv = VALIDATING_ENTRY_GET_PRIVATE (self);
 241         priv->max_func = func;
 242         priv->max_func_user_data = user_data;
 243 }
 244