class Gtk::ListStore

• Gtk::ListStore
• GObject::Object
• Reference
• Object

Overview

A list-like data structure that can be used with the Gtk::TreeView.

The Gtk::ListStore object is a list model for use with a Gtk::TreeView widget. It implements the Gtk::TreeModel interface, and consequentialy, can use all of the methods available there. It also implements the Gtk::TreeSortable interface so it can be sorted by the view. Finally, it also implements the tree drag and drop interfaces.

The Gtk::ListStore can accept most GTypes as a column type, though it can’t accept all custom types. Internally, it will keep a copy of data passed in (such as a string or a boxed pointer). Columns that accept GObjects are handled a little differently. The Gtk::ListStore will keep a reference to the object instead of copying the value. As a result, if the object is modified, it is up to the application writer to call Gtk::TreeModel#row_changed to emit the Gtk::TreeModel::#row_changed signal. This most commonly affects lists with Gdk::Textures stored.

An example for creating a simple list store:

WARNING ⚠️ The following code is in c ⚠️

enum {
  COLUMN_STRING,
  COLUMN_INT,
  COLUMN_BOOLEAN,
  N_COLUMNS
};

{
  Gtk::ListStore *list_store;
  Gtk::TreePath *path;
  Gtk::TreeIter iter;
  int i;

  list_store = gtk_list_store_new (N_COLUMNS,
                                   G_TYPE_STRING,
                                   G_TYPE_INT,
                                   G_TYPE_BOOLEAN);

  for (i = 0; i < 10; i++)
    {
      char *some_data;

      some_data = get_some_data (i);

      // Add a new row to the model
      gtk_list_store_append (list_store, &iter);
      gtk_list_store_set (list_store, &iter,
                          COLUMN_STRING, some_data,
                          COLUMN_INT, i,
                          COLUMN_BOOLEAN,  FALSE,
                          -1);

      // As the store will keep a copy of the string internally,
      // we free some_data.
      g_free (some_data);
    }

  // Modify a particular row
  path = gtk_tree_path_new_from_string ("4");
  gtk_tree_model_get_iter (GTK_TREE_MODEL (list_store),
                           &iter,
                           path);
  gtk_tree_path_free (path);
  gtk_list_store_set (list_store, &iter,
                      COLUMN_BOOLEAN, TRUE,
                      -1);
}

Performance Considerations

Internally, the Gtk::ListStore was originally implemented with a linked list with a tail pointer. As a result, it was fast at data insertion and deletion, and not fast at random data access. The Gtk::ListStore sets the GTK_TREE_MODEL_ITERS_PERSIST flag, which means that Gtk::TreeIters can be cached while the row exists. Thus, if access to a particular row is needed often and your code is expected to run on older versions of GTK, it is worth keeping the iter around.

Atomic Operations

It is important to note that only the methods gtk_list_store_insert_with_values() and gtk_list_store_insert_with_valuesv() are atomic, in the sense that the row is being appended to the store and the values filled in in a single operation with regard to Gtk::TreeModel signaling. In contrast, using e.g. gtk_list_store_append() and then gtk_list_store_set() will first create a row, which triggers the Gtk::TreeModel::row-inserted signal on Gtk::ListStore. The row, however, is still empty, and any signal handler connecting to Gtk::TreeModel::row-inserted on this particular store should be prepared for the situation that the row might be empty. This is especially important if you are wrapping the Gtk::ListStore inside a Gtk::TreeModelFilter and are using a Gtk::TreeModelFilterVisibleFunc. Using any of the non-atomic operations to append rows to the Gtk::ListStore will cause the Gtk::TreeModelFilterVisibleFunc to be visited with an empty row first; the function must be prepared for that.

Gtk::ListStore as Gtk::Buildable

The Gtk::ListStore implementation of the Gtk::Buildable interface allows to specify the model columns with a <columns> element that may contain multiple <column> elements, each specifying one model column. The “type” attribute specifies the data type for the column.

Additionally, it is possible to specify content for the list store in the UI definition, with the <data> element. It can contain multiple <row> elements, each specifying to content for one row of the list model. Inside a <row>, the <col> elements specify the content for individual cells.

Note that it is probably more common to define your models in the code, and one might consider it a layering violation to specify the content of a list store in a UI definition, data, not presentation, and common wisdom is to separate the two, as far as possible.

An example of a UI Definition fragment for a list store:

WARNING ⚠️ The following code is in xml ⚠️

<object class="Gtk::ListStore">
  <columns>
    <column type="gchararray"/>
    <column type="gchararray"/>
    <column type="gint"/>
  </columns>
  <data>
    <row>
      <col id="0">John</col>
      <col id="1">Doe</col>
      <col id="2">25</col>
    </row>
    <row>
      <col id="0">Johan</col>
      <col id="1">Dahlin</col>
      <col id="2">50</col>
    </row>
  </data>
</object>

Included Modules

• Gtk::Buildable
• Gtk::TreeDragDest
• Gtk::TreeDragSource
• Gtk::TreeModel
• Gtk::TreeSortable

Defined in:

Constructors

• .new(types : Enumerable(UInt64)) : self

  Creates a new list store as with @n_columns columns each of the types passed in.

• .new

  Initialize a new ListStore.

• .new(*types : UInt64)

Class Method Summary

• .g_type : UInt64

  Returns the type id (GType) registered in GLib type system.

Instance Method Summary

• #append : Gtk::TreeIter

  Appends a new row to @list_store.

• #clear : Nil

  Removes all rows from the list store.

• #column_types=(types : Enumerable(UInt64)) : Nil

  This function is meant primarily for GObjects that inherit from Gtk::ListStore, and should only be used when constructing a new Gtk::ListStore.

• #insert(position : Int32) : Gtk::TreeIter

  Creates a new row at @position.

• #insert_after(sibling : Gtk::TreeIter?) : Gtk::TreeIter

  Inserts a new row after @sibling.

• #insert_before(sibling : Gtk::TreeIter?) : Gtk::TreeIter

  Inserts a new row before @sibling.

• #insert_with_values(position : Int32, columns : Enumerable(Int32), values : Enumerable(_)) : Gtk::TreeIter

  Creates a new row at @position.

• #iter_is_valid(iter : Gtk::TreeIter) : Bool

  Checks if the given iter is a valid iter for this Gtk::ListStore.

• #move_after(iter : Gtk::TreeIter, position : Gtk::TreeIter?) : Nil

  Moves @iter in @store to the position after @position.

• #move_before(iter : Gtk::TreeIter, position : Gtk::TreeIter?) : Nil

  Moves @iter in @store to the position before @position.

• #prepend : Gtk::TreeIter

  Prepends a new row to @list_store.

• #remove(iter : Gtk::TreeIter) : Bool

  Removes the given row from the list store.

• #reorder(new_order : Enumerable(Int32)) : Nil

  Reorders @store to follow the order indicated by @new_order.

• #reorder(*new_order : Int32)
• #set(iter : Gtk::TreeIter, columns : Enumerable(Int32), values : Enumerable(_)) : Nil

  Sets the value of one or more cells in the row referenced by @iter.

• #set_value(iter : Gtk::TreeIter, column : Int32, value : _) : Nil

  Sets the data in the cell specified by @iter and @column.

• #swap(a : Gtk::TreeIter, b : Gtk::TreeIter) : Nil

  Swaps @a and @b in @store.

Constructor Detail

Class Method Detail

Instance Method Detail