diff --git a/source/libublsettings-gtk3.c b/source/libublsettings-gtk3.c
index 1c42cac..4f0a552 100644
--- a/source/libublsettings-gtk3.c
+++ b/source/libublsettings-gtk3.c
@@ -1190,6 +1190,27 @@ rmb_menu_window *yon_rmb_menu_setup(GtkWidget *target_widget, int (show_function
     }
 }
 
+void yon_on_text_insert_only_digits(GtkEditable *editable, const gchar *text, gint length, gint *position, gpointer user_data){
+    gchar *new_text = g_new(gchar, length + 1);
+    gint i, j = 0;
+
+    for (i = 0; i < length; i++) {
+        if (g_ascii_isdigit(text[i])) {
+            new_text[j] = text[i];
+            j++;
+        }
+    }
+
+    if (j < length) {
+        g_signal_handlers_block_by_func(editable, G_CALLBACK(yon_on_text_insert_only_digits), user_data);
+        gtk_editable_insert_text(editable, new_text, j, position);
+        g_signal_handlers_unblock_by_func(editable, G_CALLBACK(yon_on_text_insert_only_digits), user_data);
+        g_signal_stop_emission_by_name(editable, "insert-text");
+    }
+
+    g_free(new_text);
+}
+
 // GtkEntry section
 // struct entry_pattern_data {
 //     GtkEntry *entry;
diff --git a/source/libublsettings-gtk3.h b/source/libublsettings-gtk3.h
index 6567988..2382910 100644
--- a/source/libublsettings-gtk3.h
+++ b/source/libublsettings-gtk3.h
@@ -482,6 +482,8 @@ typedef struct {
 rmb_menu_window *yon_rmb_menu_setup(GtkWidget *target_widget, int (*show_function)(void*), void *show_data, const char *button_label, const char *icon_name, GCallback function, gpointer data,...);
 #endif
 
+void yon_on_text_insert_only_digits(GtkEditable *editable, const gchar *text, gint length, gint *position, gpointer user_data);
+
 // GtkTreeStore section
 
 dictionary *yon_gtk_tree_store_get_children(GtkTreeStore *tree, GtkTreeIter *parent,int column);