GraphModel Class Reference

#include <graph_model.h>

Inheritance diagram for GraphModel:

Collaboration diagram for GraphModel:

Public Member Functions
	GraphModel (QObject *parent=0)
QVariant	data (const QModelIndex &index, int role) const
	Overloads of functions required for QAbstractItemModel interface.
QModelIndex	index (int row, int column, const QModelIndex &parent=QModelIndex()) const
	Provides the index for a specific position in the model.
QModelIndex	parent (const QModelIndex &index) const
	Provides the parent for a given index.
int	rowCount (const QModelIndex &parent=QModelIndex()) const
	Number of rows.
int	columnCount (const QModelIndex &parent=QModelIndex()) const
	Number of columns.
QVariant	headerData (int section, Qt::Orientation orientation, int role=Qt::DisplayRole) const
	Provides header to use.

Public Attributes
std::map< std::string, GraphModelItem * >	items
	List of nodes that are in this tree, indexed by name in this case that might change later (?)

Protected Attributes
GraphModelItem *	root_item_
	Root Item for the data model. This is a no-use item.

Detailed Description

This is an implementation of the QAbstractItemModel interface for usage with various types of Graphs provided by Grapher. We use it in order to expose Grapher to the GUI elements such as NodeWidgets/EdgeWidgets as well as other types of Widgets like the built-in QT Tree Widget. By exposing an QAbstractItemModel like this we can fully utilize all the functionality of the QT library without having to build our own custom widgets to handle our Graph Data Type.

It is subclassed by specific implementations to generate actual models from actual graphs.

To read more about the QT Model-View architecture these are useful links: Model/View Tutorial Model/View Programming Simple Tree Model Example QAbstractItemModel reference documentation

The way that this model exposes the graph is essentially through an adjacency list. Each node is a child item from the root and then in turn has one child item per other node which it has an edge too.

In some implementations it is also possible to build a tree. The tree would then have a number of levels based on the edges emanating from the root of the tree. Each level would represent one further degree away from root.

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The documentation for this class was generated from the following files:

• src/gui/graph_model.h
• src/gui/graph_model.cc