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/*

    model.cpp

    Provides a table model for use in various examples.

*/

#include <QtGui>

#include "model.h"

/*!

    Constructs a table model with at least one row and one column.

*/

TableModel::TableModel(int rows, int columns, QObject *parent)

    : QAbstractTableModel(parent)

{

    QStringList newList;

    for (int column = 0; column < qMax(1, columns); ++column) {

        newList.append("");

    }

    for (int row = 0; row < qMax(1, rows); ++row) {

        rowList.append(newList);

    }

}

/*!

    Returns the number of items in the row list as the number of rows

    in the model.

*/

int TableModel::rowCount(const QModelIndex &/*parent*/) const

{

    return rowList.size();

}

/*!

    Returns the number of items in the first list item as the number of

    columns in the model. All rows should have the same number of columns.

*/

int TableModel::columnCount(const QModelIndex &/*parent*/) const

{

    return rowList[0].size();

}

/*!

    Returns an appropriate value for the requested data.

    If the view requests an invalid index, an invalid variant is returned.

    Any valid index that corresponds to a string in the list causes that

    string to be returned for the display role; otherwise an invalid variant

    is returned.

*/

QVariant TableModel::data(const QModelIndex &index, int role) const

{

    if (!index.isValid())

        return QVariant();

    if (role == Qt::DisplayRole)

        return rowList[index.row()][index.column()];

    else

        return QVariant();

}

/*!

    Returns the appropriate header string depending on the orientation of

    the header and the section. If anything other than the display role is

    requested, we return an invalid variant.

*/

QVariant TableModel::headerData(int section, Qt::Orientation orientation,

                                int role) const

{

    if (role != Qt::DisplayRole)

        return QVariant();

    if (orientation == Qt::Horizontal)

        return QString("Column %1").arg(section);

    else

        return QString("Row %1").arg(section);

}

/*!

    Returns an appropriate value for the item's flags. Valid items are

    enabled, selectable, and editable.

*/

Qt::ItemFlags TableModel::flags(const QModelIndex &index) const

{

    if (!index.isValid())

        return Qt::ItemIsEnabled;

    return Qt::ItemIsEnabled | Qt::ItemIsSelectable;

}

/*!

    Changes an item in the model, but only if the following conditions

    are met:

    * The index supplied is valid.

    * The role associated with editing text is specified.

    The dataChanged() signal is emitted if the item is changed.

*/

bool TableModel::setData(const QModelIndex &index,

                         const QVariant &value, int role)

{

    if (!index.isValid() || role != Qt::EditRole)

        return false;

    rowList[index.row()][index.column()] = value.toString();

    emit dataChanged(index, index);

    return true;

}

/*!

    Inserts a number of rows into the model at the specified position.

*/

bool TableModel::insertRows(int position, int rows, const QModelIndex &parent)

{

    int columns = columnCount();

    beginInsertRows(parent, position, position + rows - 1);

    for (int row = 0; row < rows; ++row) {

        QStringList items;

        for (int column = 0; column < columns; ++column)

            items.append("");

        rowList.insert(position, items);

    }

    endInsertRows();

    return true;

}

/*!

    Inserts a number of columns into the model at the specified position.

    Each entry in the list is extended in turn with the required number of

    empty strings.

*/

bool TableModel::insertColumns(int position, int columns,

                               const QModelIndex &parent)

{

    int rows = rowCount();

    beginInsertColumns(parent, position, position + columns - 1);

    for (int row = 0; row < rows; ++row) {

        for (int column = position; column < columns; ++column) {

            rowList[row].insert(position, "");

        }

    }

    endInsertColumns();

    return true;

}

/*!

    Removes a number of rows from the model at the specified position.

*/

bool TableModel::removeRows(int position, int rows, const QModelIndex &parent)

{

    beginRemoveRows(parent, position, position + rows - 1);

    for (int row = 0; row < rows; ++row) {

        rowList.removeAt(position);

    }

    endRemoveRows();

    return true;

}

/*!

    Removes a number of columns from the model at the specified position.

    Each row is shortened by the number of columns specified.

*/

bool TableModel::removeColumns(int position, int columns,

                               const QModelIndex &parent)

{

    int rows = rowCount();

    beginRemoveColumns(parent, position, position + columns - 1);

    for (int row = 0; row < rows; ++row) {

        for (int column = 0; column < columns; ++column) {

            rowList[row].removeAt(position);

        }

    }

    endRemoveColumns();

    return true;

}