gtk-0.14.5: Binding to the Gtk+ graphical user interface library.

Maintainer gtk2hs-users@lists.sourceforge.net provisional portable (depends on GHC) None Haskell98

Graphics.UI.Gtk.ModelView.TreeStore

Description

Standard model to store hierarchical data.

Synopsis

# Types

data TreeStore a Source #

A store for hierarchical data.

Instances

 Source # Methodsdummy :: TreeStore a -> a Source # Methods Source #

# Constructors

treeStoreNew :: Forest a -> IO (TreeStore a) Source #

Create a new list store.

• The given rose tree determines the initial content and may be the empty list. Each Tree in the forest corresponds to one top-level node.
• The TreeStore maintains the initially given Forest and aligns the TreePath bits to fit in 96-bit length TreeIter storage.
• Additionally, a cache is used to achieve higher performance if operating on recently used TreePaths.
• Note: due to the limited amount of bits available in TreeIter storage, only limited depth forests can be used with this implementation, the result of too deep Forests is an undefined behaviour while trying to retrieve the deeply nested nodes. For example: assuming the average requiement is 8 bits per tree level (max number of children at the level is 255), then we can only use 12 levels deep trees (96/8) - any further levels in a TreePath will not be encoded in the corresponding TreeIter storage.

Arguments

 :: Forest a the inital tree stored in this model -> Maybe (DragSourceIface TreeStore a) an optional interface for drags -> Maybe (DragDestIface TreeStore a) an optional interface to handle drops -> IO (TreeStore a)

Create a new list store.

• In addition to treeStoreNew, this function takes an two interfaces to implement user-defined drag-and-drop functionality.

# Implementation of Interfaces

Default drag functions for TreeStore. These functions allow the rows of the model to serve as drag source. Any row is allowed to be dragged and the data set in the SelectionDataM object is set with treeSetRowDragData, i.e. it contains the model and the TreePath to the row.

Default drop functions for TreeStore. These functions accept a row and insert the row into the new location if it is dragged into a tree view that uses the same model.

# Methods

Extract one node from the current model. Fails if the given TreePath refers to a non-existent node.

Extract a subtree from the current model. Fails if the given TreePath refers to a non-existent node.

treeStoreLookup :: TreeStore a -> TreePath -> IO (Maybe (Tree a)) Source #

Extract a subtree from the current model. Like treeStoreGetTree but returns Nothing if the path refers to a non-existant node.

treeStoreSetValue :: TreeStore a -> TreePath -> a -> IO () Source #

Set a node in the store.

Arguments

 :: TreeStore a the store -> TreePath path - the position of the parent -> Int pos - the index of the new tree -> a the value to be inserted -> IO ()

Insert a single node into the store.

• This function inserts a single node without children into the tree. Its arguments are similar to those of treeStoreInsert.

Arguments

 :: TreeStore a the store -> TreePath path - the position of the parent -> Int pos - the index of the new tree -> Tree a the value to be inserted -> IO ()

Insert a node into the store.

Arguments

 :: TreeStore a the store -> TreePath path - the position of the parent -> Int pos - the index of the new tree -> Forest a the list of trees to be inserted -> IO ()

Insert nodes into the store.

• The given list of nodes is inserted into given parent at pos. If the parent existed, the function returns Just path where path is the position of the newly inserted elements. If pos is negative or greater or equal to the number of children of the node at path, the new nodes are appended to the list.

Remove a node from the store.

• The node denoted by the path is removed, along with all its children. The function returns True if the given node was found.

treeStoreChange :: TreeStore a -> TreePath -> (a -> a) -> IO Bool Source #

Change a node in the store.

• Returns True if the node was found. For a monadic version, see treeStoreChangeM.

treeStoreChangeM :: TreeStore a -> TreePath -> (a -> IO a) -> IO Bool Source #

Change a node in the store.

• Returns True if the node was found. For a purely functional version, see treeStoreChange.