Class TreeModelSort

All Implemented Interfaces:
PointerInterface

public class TreeModelSort extends Object
A GtkTreeModel which makes an underlying tree model sortable

The `GtkTreeModelSort` is a model which implements the `GtkTreeSortable`
interface. It does not hold any data itself, but rather is created with
a child model and proxies its data. It has identical column types to
this child model, and the changes in the child are propagated. The
primary purpose of this model is to provide a way to sort a different
model without modifying it. Note that the sort function used by
`GtkTreeModelSort` is not guaranteed to be stable.

The use of this is best demonstrated through an example. In the
following sample code we create two `GtkTreeView` widgets each with a
view of the same data. As the model is wrapped here by a
`GtkTreeModelSort`, the two `GtkTreeView`s can each sort their
view of the data without affecting the other. By contrast, if we
simply put the same model in each widget, then sorting the first would
sort the second.

## Using a `GtkTreeModelSort`
<!-- language="C" -->
 {
   GtkTreeView *tree_view1;
   GtkTreeView *tree_view2;
   GtkTreeModel *sort_model1;
   GtkTreeModel *sort_model2;
   GtkTreeModel *child_model;
 
   // get the child model
   child_model = get_my_model ();
 
   // Create the first tree
   sort_model1 = gtk_tree_model_sort_new_with_model (child_model);
   tree_view1 = gtk_tree_view_new_with_model (sort_model1);
 
   // Create the second tree
   sort_model2 = gtk_tree_model_sort_new_with_model (child_model);
   tree_view2 = gtk_tree_view_new_with_model (sort_model2);
 
   // Now we can sort the two models independently
   gtk_tree_sortable_set_sort_column_id (GTK_TREE_SORTABLE (sort_model1),
                                         COLUMN_1, GTK_SORT_ASCENDING);
   gtk_tree_sortable_set_sort_column_id (GTK_TREE_SORTABLE (sort_model2),
                                         COLUMN_1, GTK_SORT_DESCENDING);
 }
 


To demonstrate how to access the underlying child model from the sort
model, the next example will be a callback for the `GtkTreeSelection`
`GtkTreeSelection::changed` signal. In this callback, we get a string
from COLUMN_1 of the model. We then modify the string, find the same
selected row on the child model, and change the row there.

## Accessing the child model of in a selection changed callback
<!-- language="C" -->
 void
 selection_changed (GtkTreeSelection *selection, gpointer data)
 {
   GtkTreeModel *sort_model = NULL;
   GtkTreeModel *child_model;
   GtkTreeIter sort_iter;
   GtkTreeIter child_iter;
   char *some_data = NULL;
   char *modified_data;
 
   // Get the current selected row and the model.
   if (! gtk_tree_selection_get_selected (selection,
                                          &sort_model,
                                          &sort_iter))
     return;
 
   // Look up the current value on the selected row and get
   // a new value to change it to.
   gtk_tree_model_get (GTK_TREE_MODEL (sort_model), &sort_iter,
                       COLUMN_1, &some_data,
                       -1);
 
   modified_data = change_the_data (some_data);
   g_free (some_data);
 
   // Get an iterator on the child model, instead of the sort model.
   gtk_tree_model_sort_convert_iter_to_child_iter (GTK_TREE_MODEL_SORT (sort_model),
                                                   &child_iter,
                                                   &sort_iter);
 
   // Get the child model and change the value of the row. In this
   // example, the child model is a GtkListStore. It could be any other
   // type of model, though.
   child_model = gtk_tree_model_sort_get_model (GTK_TREE_MODEL_SORT (sort_model));
   gtk_list_store_set (GTK_LIST_STORE (child_model), &child_iter,
                       COLUMN_1, &modified_data,
                       -1);
   g_free (modified_data);
 }
 

https://docs.gtk.org/gtk4/class.TreeModelSort.html

  • Constructor Details

  • Method Details

    • getClassHandler

      public static ClassHandler getClassHandler()
    • newWithModelTreeModelSort

      public static TreeModelSort newWithModelTreeModelSort(@Nonnull TreeModel child_model)
      Creates a new `GtkTreeModelSort`, with @child_model as the child model.
      Parameters:
      child_model - A `GtkTreeModel`
      Returns:
      A new `GtkTreeModelSort`.
    • clearCache

      public void clearCache()
      This function should almost never be called. It clears the @tree_model_sort
      of any cached iterators that haven’t been reffed with
      gtk_tree_model_ref_node(). This might be useful if the child model being
      sorted is static (and doesn’t change often) and there has been a lot of
      unreffed access to nodes. As a side effect of this function, all unreffed
      iters will be invalid.
    • convertChildIterToIter

      public boolean convertChildIterToIter(@Nonnull TreeIter sort_iter, @Nonnull TreeIter child_iter)
      Sets @sort_iter to point to the row in @tree_model_sort that corresponds to
      the row pointed at by @child_iter. If @sort_iter was not set, %FALSE
      is returned. Note: a boolean is only returned since 2.14.
      Parameters:
      sort_iter - An uninitialized `GtkTreeIter`
      child_iter - A valid `GtkTreeIter` pointing to a row on the child model
      Returns:
      %TRUE, if @sort_iter was set, i.e. if @sort_iter is a valid iterator pointer to a visible row in the child model.
    • convertChildPathToPath

      public TreePath convertChildPathToPath(@Nonnull TreePath child_path)
      Converts @child_path to a path relative to @tree_model_sort. That is,
      @child_path points to a path in the child model. The returned path will
      point to the same row in the sorted model. If @child_path isn’t a valid
      path on the child model, then %NULL is returned.
      Parameters:
      child_path - A `GtkTreePath` to convert
      Returns:
      A newly allocated `GtkTreePath`
    • convertIterToChildIter

      public void convertIterToChildIter(@Nonnull TreeIter child_iter, @Nonnull TreeIter sorted_iter)
      Sets @child_iter to point to the row pointed to by @sorted_iter.
      Parameters:
      child_iter - An uninitialized `GtkTreeIter`
      sorted_iter - A valid `GtkTreeIter` pointing to a row on @tree_model_sort.
    • convertPathToChildPath

      public TreePath convertPathToChildPath(@Nonnull TreePath sorted_path)
      Converts @sorted_path to a path on the child model of @tree_model_sort.
      That is, @sorted_path points to a location in @tree_model_sort. The
      returned path will point to the same location in the model not being
      sorted. If @sorted_path does not point to a location in the child model,
      %NULL is returned.
      Parameters:
      sorted_path - A `GtkTreePath` to convert
      Returns:
      A newly allocated `GtkTreePath`
    • getModel

      public TreeModel getModel()
      Returns the model the `GtkTreeModelSort` is sorting.
      Returns:
      the "child model" being sorted
    • iterIsValid

      public boolean iterIsValid(@Nonnull TreeIter iter)
      > This function is slow. Only use it for debugging and/or testing
      > purposes.

      Checks if the given iter is a valid iter for this `GtkTreeModelSort`.
      Parameters:
      iter - A `GtkTreeIter`
      Returns:
      %TRUE if the iter is valid, %FALSE if the iter is invalid.
    • resetDefaultSortFunc

      public void resetDefaultSortFunc()
      This resets the default sort function to be in the “unsorted” state. That
      is, it is in the same order as the child model. It will re-sort the model
      to be in the same order as the child model only if the `GtkTreeModelSort`
      is in “unsorted” state.
    • asTreeDragSource

      public TreeDragSource asTreeDragSource()
      Implements interface TreeDragSource. Call this to get access to interface functions.
      Returns:
      TreeDragSource
    • asTreeModel

      public TreeModel asTreeModel()
      Implements interface TreeModel. Call this to get access to interface functions.
      Returns:
      TreeModel
    • asTreeSortable

      public TreeSortable asTreeSortable()
      Implements interface TreeSortable. Call this to get access to interface functions.
      Returns:
      TreeSortable
    • getTypeID

      public static long getTypeID()
    • getParentTypeID

      public static long getParentTypeID()
    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()
    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()
    • getInstanceSize

      public static int getInstanceSize()