gtk.TreeIter.TreeIter Class Reference

List of all members.

Detailed Description

Description The GtkTreeModel interface defines a generic tree interface for use by the GtkTreeView widget.

It is an abstract interface, and is designed to be usable with any appropriate data structure. The programmer just has to implement this interface on their own data type for it to be viewable by a GtkTreeView widget. The model is represented as a hierarchical tree of strongly-typed, columned data. In other words, the model can be seen as a tree where every node has different values depending on which column is being queried. The type of data found in a column is determined by using the GType system (ie. G_TYPE_INT, GTK_TYPE_BUTTON, G_TYPE_POINTER, etc.). The types are homogeneous per column across all nodes. It is important to note that this interface only provides a way of examining a model and observing changes. The implementation of each individual model decides how and if changes are made. In order to make life simpler for programmers who do not need to write their own specialized model, two generic models are provided the GtkTreeStore and the GtkListStore. To use these, the developer simply pushes data into these models as necessary. These models provide the data structure as well as all appropriate tree interfaces. As a result, implementing drag and drop, sorting, and storing data is trivial. For the vast majority of trees and lists, these two models are sufficient. Models are accessed on a node/column level of granularity. One can query for the value of a model at a certain node and a certain column on that node. There are two structures used to reference a particular node in a model. They are the GtkTreePath and the GtkTreeIter [4] Most of the interface consists of operations on a GtkTreeIter. A path is essentially a potential node. It is a location on a model that may or may not actually correspond to a node on a specific model. The GtkTreePath struct can be converted into either an array of unsigned integers or a string. The string form is a list of numbers separated by a colon. Each number refers to the offset at that level. Thus, the path 0 refers to the root node and the path 2:4 refers to the fifth child of the third node. By contrast, a GtkTreeIter is a reference to a specific node on a specific model. It is a generic struct with an integer and three generic pointers. These are filled in by the model in a model-specific way. One can convert a path to an iterator by calling gtk_tree_model_get_iter(). These iterators are the primary way of accessing a model and are similar to the iterators used by GtkTextBuffer. They are generally statically allocated on the stack and only used for a short time. The model interface defines a set of operations using them for navigating the model. It is expected that models fill in the iterator with private data. For example, the GtkListStore model, which is internally a simple linked list, stores a list node in one of the pointers. The GtkTreeModelSort stores an array and an offset in two of the pointers. Additionally, there is an integer field. This field is generally filled with a unique stamp per model. This stamp is for catching errors resulting from using invalid iterators with a model. The lifecycle of an iterator can be a little confusing at first. Iterators are expected to always be valid for as long as the model is unchanged (and doesn't emit a signal). The model is considered to own all outstanding iterators and nothing needs to be done to free them from the user's point of view. Additionally, some models guarantee that an iterator is valid for as long as the node it refers to is valid (most notably the GtkTreeStore and GtkListStore). Although generally uninteresting, as one always has to allow for the case where iterators do not persist beyond a signal, some very important performance enhancements were made in the sort model. As a result, the GTK_TREE_MODEL_ITERS_PERSIST flag was added to indicate this behavior. To help show some common operation of a model, some examples are provided. The first example shows three ways of getting the iter at the location 3:2:5. While the first method shown is easier, the second is much more common, as you often get paths from callbacks. Example1.Acquiring a GtkTreeIter /+* Three ways of getting the iter pointing to the location +/ { GtkTreePath *path; GtkTreeIter iter; GtkTreeIter parent_iter; /+* get the iterator from a string +/ gtk_tree_model_get_iter_from_string (model, iter, "3:2:5"); /+* get the iterator from a path +/ path = gtk_tree_path_new_from_string ("3:2:5"); gtk_tree_model_get_iter (model, iter, path); gtk_tree_path_free (path); /+* walk the tree to find the iterator +/ gtk_tree_model_iter_nth_child (model, iter, NULL, 3); parent_iter = iter; gtk_tree_model_iter_nth_child (model, iter, parent_iter, 2); parent_iter = iter; gtk_tree_model_iter_nth_child (model, iter, parent_iter, 5); } This second example shows a quick way of iterating through a list and getting a string and an integer from each row. The populate_model function used below is not shown, as it is specific to the GtkListStore. For information on how to write such a function, see the GtkListStore documentation. Example2.Reading data from a GtkTreeModel enum { STRING_COLUMN, INT_COLUMN, N_COLUMNS }; { GtkTreeModel *list_store; GtkTreeIter iter; gboolean valid; gint row_count = 0; /+* make a new list_store +/ list_store = gtk_list_store_new (N_COLUMNS, G_TYPE_STRING, G_TYPE_INT); /+* Fill the list store with data +/ populate_model (list_store); /+* Get the first iter in the list +/ valid = gtk_tree_model_get_iter_first (list_store, iter); while (valid) { /+* Walk through the list, reading each row +/ gchar *str_data; gint int_data; /+* Make sure you terminate calls to gtk_tree_model_get() * with a '-1' value +/ gtk_tree_model_get (list_store, iter, STRING_COLUMN, str_data, INT_COLUMN, int_data, -1); /+* Do something with the data +/ g_print ("Row %d: (%s,%d)\n", row_count, str_data, int_data); g_free (str_data); row_count ++; valid = gtk_tree_model_iter_next (list_store, iter); } }


Public Member Functions

GtkTreeItergetTreeIterStruct ()
 this (GtkTreeIter *gtkTreeIter)
 Sets our main struct and passes it to the parent class.
void setModel (GtkTreeModel *gtkTreeModel)
void setModel (TreeModel treeModel)
 this (TreeModel treeModel, TreePath treePath)
 this ()
 creates a new tree iteractor.
void getValue (int column, Value value)
 Get Value.
char[] getValueString (int column)
 Get the value of a column as a string column the column number.
int getValueInt (int column)
 Get the value of a column as an int column the column number.
TreePath getTreePath ()
char[] getVisiblePath (char[] separator)
 This return the path visible to the user.
TreeIter getParent ()
 Gets the parent of this iter.
TreeIter getGrandParent ()
void delegate (GtkTreePath *, TreeIter, TreeIter)[] onRowChangedListeners
void addOnRowChanged (void delegate(GtkTreePath *, TreeIter, TreeIter) dlg)
 extern (C) static void callBackRowChanged(GtkTreeModel *treeModelStruct
void addOnRowDeleted (void delegate(GtkTreePath *, TreeIter) dlg)
 extern (C) static void callBackRowDeleted(GtkTreeModel *treeModelStruct
void addOnRowHasChildToggled (void delegate(GtkTreePath *, TreeIter, TreeIter) dlg)
 extern (C) static void callBackRowHasChildToggled(GtkTreeModel *treeModelStruct
void addOnRowInserted (void delegate(GtkTreePath *, TreeIter, TreeIter) dlg)
 extern (C) static void callBackRowInserted(GtkTreeModel *treeModelStruct
void addOnRowsReordered (void delegate(GtkTreePath *, TreeIter, gpointer, TreeIter) dlg)
 extern (C) static void callBackRowsReordered(GtkTreeModel *treeModelStruct

Public Attributes

GtkTreeModelgtkTreeModel
 this will be set only when the iter is created from the model.
int[char[]] connectedSignals
GtkTreePathpath
GtkTreePath GtkTreeIteriter
GtkTreePathpath
GtkTreePathpath
GtkTreePath GtkTreeIteriter
GtkTreePathpath
GtkTreePath GtkTreeIteriter
GtkTreePathpath
GtkTreePath GtkTreeIteriter
GtkTreePath GtkTreeIter gpointer arg3

Protected Member Functions

void * getStruct ()
 the main Gtk struct as a void*

Protected Attributes

GtkTreeItergtkTreeIter
 the main Gtk struct


Constructor & Destructor Documentation

gtk.TreeIter.TreeIter.this ( GtkTreeIter gtkTreeIter  ) 

Sets our main struct and passes it to the parent class.

gtk.TreeIter.TreeIter.this ( TreeModel  treeModel,
TreePath  treePath 
)

gtk.TreeIter.TreeIter.this (  ) 

creates a new tree iteractor.

used TreeView.createIter and TreeView.append() to create iteractor for a tree or list


Member Function Documentation

void gtk.TreeIter.TreeIter.addOnRowChanged ( void delegate(GtkTreePath *, TreeIter, TreeIter dlg  ) 

void gtk.TreeIter.TreeIter.addOnRowDeleted ( void delegate(GtkTreePath *, TreeIter dlg  ) 

void gtk.TreeIter.TreeIter.addOnRowHasChildToggled ( void delegate(GtkTreePath *, TreeIter, TreeIter dlg  ) 

void gtk.TreeIter.TreeIter.addOnRowInserted ( void delegate(GtkTreePath *, TreeIter, TreeIter dlg  ) 

void gtk.TreeIter.TreeIter.addOnRowsReordered ( void delegate(GtkTreePath *, TreeIter, gpointer, TreeIter dlg  ) 

void gtk.TreeIter.TreeIter.delegate ( GtkTreePath ,
TreeIter  ,
TreeIter   
)

gtk.TreeIter.TreeIter.extern (  ) 

gtk.TreeIter.TreeIter.extern (  ) 

gtk.TreeIter.TreeIter.extern (  ) 

gtk.TreeIter.TreeIter.extern (  ) 

gtk.TreeIter.TreeIter.extern (  ) 

TreeIter gtk.TreeIter.TreeIter.getGrandParent (  ) 

TreeIter gtk.TreeIter.TreeIter.getParent (  ) 

Gets the parent of this iter.

Parameters:
child 
Returns:
the parent iter or null if can't get parent or an error occured

void* gtk.TreeIter.TreeIter.getStruct (  )  [protected]

the main Gtk struct as a void*

GtkTreeIter* gtk.TreeIter.TreeIter.getTreeIterStruct (  ) 

TreePath gtk.TreeIter.TreeIter.getTreePath (  ) 

void gtk.TreeIter.TreeIter.getValue ( int  column,
Value  value 
)

Get Value.

Parameters:
iter 
column 
value 

int gtk.TreeIter.TreeIter.getValueInt ( int  column  ) 

Get the value of a column as an int column the column number.

Returns:
a string representing the value of the column

char [] gtk.TreeIter.TreeIter.getValueString ( int  column  ) 

Get the value of a column as a string column the column number.

Returns:
a string representing the value of the column

char [] gtk.TreeIter.TreeIter.getVisiblePath ( char[]  separator  ) 

This return the path visible to the user.

void gtk.TreeIter.TreeIter.setModel ( TreeModel  treeModel  ) 

void gtk.TreeIter.TreeIter.setModel ( GtkTreeModel gtkTreeModel  ) 


Member Data Documentation

GtkTreePath GtkTreeIter gpointer gtk.TreeIter.TreeIter.arg3

int [char[]] gtk.TreeIter.TreeIter.connectedSignals

GtkTreeIter* gtk.TreeIter.TreeIter.gtkTreeIter [protected]

the main Gtk struct

GtkTreeModel* gtk.TreeIter.TreeIter.gtkTreeModel

this will be set only when the iter is created from the model.

GtkTreePath GtkTreeIter* gtk.TreeIter.TreeIter.iter

GtkTreePath GtkTreeIter* gtk.TreeIter.TreeIter.iter

GtkTreePath GtkTreeIter* gtk.TreeIter.TreeIter.iter

GtkTreePath GtkTreeIter* gtk.TreeIter.TreeIter.iter

GtkTreePath* gtk.TreeIter.TreeIter.path

GtkTreePath* gtk.TreeIter.TreeIter.path

GtkTreePath* gtk.TreeIter.TreeIter.path

GtkTreePath* gtk.TreeIter.TreeIter.path

GtkTreePath* gtk.TreeIter.TreeIter.path


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