GtkTreeModelFilter

GtkTreeModelFilter — A GtkTreeModel which hides parts of an underlying tree model

Synopsis

#include <gtk/gtk.h>

                    GtkTreeModelFilter;
gboolean            (*GtkTreeModelFilterVisibleFunc)    (GtkTreeModel *model,
                                                         GtkTreeIter *iter,
                                                         gpointer data);
void                (*GtkTreeModelFilterModifyFunc)     (GtkTreeModel *model,
                                                         GtkTreeIter *iter,
                                                         GValue *value,
                                                         gint column,
                                                         gpointer data);
GtkTreeModel *      gtk_tree_model_filter_new           (GtkTreeModel *child_model,
                                                         GtkTreePath *root);
void                gtk_tree_model_filter_set_visible_func
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreeModelFilterVisibleFunc func,
                                                         gpointer data,
                                                         GDestroyNotify destroy);
void                gtk_tree_model_filter_set_modify_func
                                                        (GtkTreeModelFilter *filter,
                                                         gint n_columns,
                                                         GType *types,
                                                         GtkTreeModelFilterModifyFunc func,
                                                         gpointer data,
                                                         GDestroyNotify destroy);
void                gtk_tree_model_filter_set_visible_column
                                                        (GtkTreeModelFilter *filter,
                                                         gint column);
GtkTreeModel *      gtk_tree_model_filter_get_model     (GtkTreeModelFilter *filter);
gboolean            gtk_tree_model_filter_convert_child_iter_to_iter
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreeIter *filter_iter,
                                                         GtkTreeIter *child_iter);
void                gtk_tree_model_filter_convert_iter_to_child_iter
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreeIter *child_iter,
                                                         GtkTreeIter *filter_iter);
GtkTreePath *       gtk_tree_model_filter_convert_child_path_to_path
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreePath *child_path);
GtkTreePath *       gtk_tree_model_filter_convert_path_to_child_path
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreePath *filter_path);
void                gtk_tree_model_filter_refilter      (GtkTreeModelFilter *filter);
void                gtk_tree_model_filter_clear_cache   (GtkTreeModelFilter *filter);

Object Hierarchy

  GObject
   +----GtkTreeModelFilter

Implemented Interfaces

GtkTreeModelFilter implements GtkTreeModel and GtkTreeDragSource.

Properties

  "child-model"              GtkTreeModel*         : Read / Write / Construct Only
  "virtual-root"             GtkTreePath*          : Read / Write / Construct Only

Description

A GtkTreeModelFilter is a tree model which wraps another tree model, and can do the following things:

  • Filter specific rows, based on data from a "visible column", a column storing booleans indicating whether the row should be filtered or not, or based on the return value of a "visible function", which gets a model, iter and user_data and returns a boolean indicating whether the row should be filtered or not.

  • Modify the "appearance" of the model, using a modify function. This is extremely powerful and allows for just changing some values and also for creating a completely different model based on the given child model.

  • Set a different root node, also known as a "virtual root". You can pass in a GtkTreePath indicating the root node for the filter at construction time.

Details

GtkTreeModelFilter

typedef struct _GtkTreeModelFilter GtkTreeModelFilter;

The GtkTreeModelFilter struct contains only private fields.


GtkTreeModelFilterVisibleFunc ()

gboolean            (*GtkTreeModelFilterVisibleFunc)    (GtkTreeModel *model,
                                                         GtkTreeIter *iter,
                                                         gpointer data);

A function which decides whether the row indicated by iter is visible.

model :

the child model of the GtkTreeModelFilter

iter :

a GtkTreeIter pointing to the row in model whose visibility is determined

data :

user data given to gtk_tree_model_filter_set_visible_func()

Returns :

Whether the row indicated by iter is visible.

GtkTreeModelFilterModifyFunc ()

void                (*GtkTreeModelFilterModifyFunc)     (GtkTreeModel *model,
                                                         GtkTreeIter *iter,
                                                         GValue *value,
                                                         gint column,
                                                         gpointer data);

A function which calculates display values from raw values in the model. It must fill value with the display value for the column column in the row indicated by iter.

Since this function is called for each data access, it's not a particularly efficient operation.

model :

the GtkTreeModelFilter

iter :

a GtkTreeIter pointing to the row whose display values are determined

value :

A GValue which is already initialized for with the correct type for the column column.

column :

the column whose display value is determined

data :

user data given to gtk_tree_model_filter_set_modify_func()

gtk_tree_model_filter_new ()

GtkTreeModel *      gtk_tree_model_filter_new           (GtkTreeModel *child_model,
                                                         GtkTreePath *root);

Creates a new GtkTreeModel, with child_model as the child_model and root as the virtual root.

child_model :

A GtkTreeModel.

root :

A GtkTreePath or NULL.. allow-none.

Returns :

A new GtkTreeModel.

Since 2.4


gtk_tree_model_filter_set_visible_func ()

void                gtk_tree_model_filter_set_visible_func
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreeModelFilterVisibleFunc func,
                                                         gpointer data,
                                                         GDestroyNotify destroy);

Sets the visible function used when filtering the filter to be func. The function should return TRUE if the given row should be visible and FALSE otherwise.

If the condition calculated by the function changes over time (e.g. because it depends on some global parameters), you must call gtk_tree_model_filter_refilter() to keep the visibility information of the model uptodate.

Note that func is called whenever a row is inserted, when it may still be empty. The visible function should therefore take special care of empty rows, like in the example below.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
static gboolean
visible_func (GtkTreeModel *model,
              GtkTreeIter  *iter,
              gpointer      data)
{
  /* Visible if row is non-empty and first column is "HI" */
  gchar *str;
  gboolean visible = FALSE;

  gtk_tree_model_get (model, iter, 0, &str, -1);
  if (str && strcmp (str, "HI") == 0)
    visible = TRUE;
  g_free (str);

  return visible;
}

filter :

A GtkTreeModelFilter.

func :

A GtkTreeModelFilterVisibleFunc, the visible function.

data :

User data to pass to the visible function, or NULL.. allow-none.

destroy :

Destroy notifier of data, or NULL.. allow-none.

Since 2.4


gtk_tree_model_filter_set_modify_func ()

void                gtk_tree_model_filter_set_modify_func
                                                        (GtkTreeModelFilter *filter,
                                                         gint n_columns,
                                                         GType *types,
                                                         GtkTreeModelFilterModifyFunc func,
                                                         gpointer data,
                                                         GDestroyNotify destroy);

With the n_columns and types parameters, you give an array of column types for this model (which will be exposed to the parent model/view). The func, data and destroy parameters are for specifying the modify function. The modify function will get called for each data access, the goal of the modify function is to return the data which should be displayed at the location specified using the parameters of the modify function.

filter :

A GtkTreeModelFilter.

n_columns :

The number of columns in the filter model.

types :

The GTypes of the columns.

func :

A GtkTreeModelFilterModifyFunc

data :

User data to pass to the modify function, or NULL.. allow-none.

destroy :

Destroy notifier of data, or NULL.. allow-none.

Since 2.4


gtk_tree_model_filter_set_visible_column ()

void                gtk_tree_model_filter_set_visible_column
                                                        (GtkTreeModelFilter *filter,
                                                         gint column);

Sets column of the child_model to be the column where filter should look for visibility information. columns should be a column of type G_TYPE_BOOLEAN, where TRUE means that a row is visible, and FALSE if not.

filter :

A GtkTreeModelFilter.

column :

A gint which is the column containing the visible information.

Since 2.4


gtk_tree_model_filter_get_model ()

GtkTreeModel *      gtk_tree_model_filter_get_model     (GtkTreeModelFilter *filter);

Returns a pointer to the child model of filter.

filter :

A GtkTreeModelFilter.

Returns :

A pointer to a GtkTreeModel.

Since 2.4


gtk_tree_model_filter_convert_child_iter_to_iter ()

gboolean            gtk_tree_model_filter_convert_child_iter_to_iter
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreeIter *filter_iter,
                                                         GtkTreeIter *child_iter);

Sets filter_iter to point to the row in filter that corresponds to the row pointed at by child_iter. If filter_iter was not set, FALSE is returned.

filter :

A GtkTreeModelFilter.

filter_iter :

An uninitialized GtkTreeIter.

child_iter :

A valid GtkTreeIter pointing to a row on the child model.

Returns :

TRUE, if filter_iter was set, i.e. if child_iter is a valid iterator pointing to a visible row in child model.

Since 2.4


gtk_tree_model_filter_convert_iter_to_child_iter ()

void                gtk_tree_model_filter_convert_iter_to_child_iter
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreeIter *child_iter,
                                                         GtkTreeIter *filter_iter);

Sets child_iter to point to the row pointed to by filter_iter.

filter :

A GtkTreeModelFilter.

child_iter :

An uninitialized GtkTreeIter.

filter_iter :

A valid GtkTreeIter pointing to a row on filter.

Since 2.4


gtk_tree_model_filter_convert_child_path_to_path ()

GtkTreePath *       gtk_tree_model_filter_convert_child_path_to_path
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreePath *child_path);

Converts child_path to a path relative to filter. That is, child_path points to a path in the child model. The rerturned path will point to the same row in the filtered model. If child_path isn't a valid path on the child model or points to a row which is not visible in filter, then NULL is returned.

filter :

A GtkTreeModelFilter.

child_path :

A GtkTreePath to convert.

Returns :

A newly allocated GtkTreePath, or NULL.

Since 2.4


gtk_tree_model_filter_convert_path_to_child_path ()

GtkTreePath *       gtk_tree_model_filter_convert_path_to_child_path
                                                        (GtkTreeModelFilter *filter,
                                                         GtkTreePath *filter_path);

Converts filter_path to a path on the child model of filter. That is, filter_path points to a location in filter. The returned path will point to the same location in the model not being filtered. If filter_path does not point to a location in the child model, NULL is returned.

filter :

A GtkTreeModelFilter.

filter_path :

A GtkTreePath to convert.

Returns :

A newly allocated GtkTreePath, or NULL.

Since 2.4


gtk_tree_model_filter_refilter ()

void                gtk_tree_model_filter_refilter      (GtkTreeModelFilter *filter);

Emits ::row_changed for each row in the child model, which causes the filter to re-evaluate whether a row is visible or not.

filter :

A GtkTreeModelFilter.

Since 2.4


gtk_tree_model_filter_clear_cache ()

void                gtk_tree_model_filter_clear_cache   (GtkTreeModelFilter *filter);

This function should almost never be called. It clears the filter of any cached iterators that haven't been reffed with gtk_tree_model_ref_node(). This might be useful if the child model being filtered 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.

filter :

A GtkTreeModelFilter.

Since 2.4

Property Details

The "child-model" property

  "child-model"              GtkTreeModel*         : Read / Write / Construct Only

The model for the filtermodel to filter.


The "virtual-root" property

  "virtual-root"             GtkTreePath*          : Read / Write / Construct Only

The virtual root (relative to the child model) for this filtermodel.

See Also

GtkTreeModelSort