28 ClutterModel

A generic model implementation

28.1 Overview

<clutter-model> is a generic list model API which can be used to implement the model-view-controller architectural pattern in Clutter.

The <clutter-model> class is a list model which can accept most GObject types as a column type.

Creating a simple clutter model:

     
     enum
     {
       COLUMN_INT,
       COLUMN_STRING,
     
       N_COLUMNS
     };
     
     {
       ClutterModel *model;
       gint i;
     
       model = clutter_model_default_new (N_COLUMNS,
                                          /* column type, column title */
                                          G_TYPE_INT,     "my integers",
                                          G_TYPE_STRING,  "my strings");
       for (i = 0; i < 10; i++)
         {
           gchar *string = g_strdup_printf ("String %d", i);
           clutter_model_append (model,
                                 COLUMN_INT, i,
                                 COLUMN_STRING, string,
                                 -1);
           g_free (string);
         }
     
     
     }

Iterating through the model consists of retrieving a new <clutter-model-iter> pointing to the starting row, and calling clutter-model-iter-next or clutter-model-iter-prev to move forward or backwards, repectively.

A valid <clutter-model-iter> represents the position between two rows in the model. For example, the "first" iterator represents the gap immediately before the first row, and the "last" iterator represents the gap immediately after the last row. In an empty sequence, the first and last iterators are the same.

Iterating a <"">

     
     enum
     {
       COLUMN_INT,
       COLUMN_STRING.
     
       N_COLUMNS
     };
     
     {
       ClutterModel *model;
       ClutterModelIter *iter = NULL;
     
       /*  Fill the model */
       model = populate_model ();
     
       /* Get the first iter */
       iter = clutter_model_get_first_iter (model);
       while (!clutter_model_iter_is_last (iter))
         {
           print_row (iter);
     
           iter = clutter_model_iter_next (iter);
         }
     
       /* Make sure to unref the iter */
       g_object_unref (iter);
     }

<clutter-model> is an abstract class. Clutter provides a default model implementation called <clutter-model-default> which has been optimised for insertion and look up in sorted lists.

<clutter-model> is available since Clutter 0.6

28.2 Usage