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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
//! [quoting modelview_a]
#include "mainwindow.h"
#include <QTreeView>
#include <QStandardItemModel>
#include <QItemSelectionModel>
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, treeView(new QTreeView(this))
, standardModel(new QStandardItemModel(this))
{
setCentralWidget(treeView);
auto *rootNode = standardModel->invisibleRootItem();
// defining a couple of items
auto *americaItem = new QStandardItem("America");
auto *mexicoItem = new QStandardItem("Canada");
auto *usaItem = new QStandardItem("USA");
auto *bostonItem = new QStandardItem("Boston");
auto *europeItem = new QStandardItem("Europe");
auto *italyItem = new QStandardItem("Italy");
auto *romeItem = new QStandardItem("Rome");
auto *veronaItem = new QStandardItem("Verona");
// building up the hierarchy
rootNode-> appendRow(americaItem);
rootNode-> appendRow(europeItem);
americaItem-> appendRow(mexicoItem);
americaItem-> appendRow(usaItem);
usaItem-> appendRow(bostonItem);
europeItem-> appendRow(italyItem);
italyItem-> appendRow(romeItem);
italyItem-> appendRow(veronaItem);
// register the model
treeView->setModel(standardModel);
treeView->expandAll();
// selection changes shall trigger a slot
QItemSelectionModel *selectionModel = treeView->selectionModel();
connect(selectionModel, &QItemSelectionModel::selectionChanged,
this, &MainWindow::selectionChangedSlot);
}
//! [quoting modelview_a]
//------------------------------------------------------------------------------------
//! [quoting modelview_b]
void MainWindow::selectionChangedSlot(const QItemSelection & /*newSelection*/, const QItemSelection & /*oldSelection*/)
{
// get the text of the selected item
const QModelIndex index = treeView->selectionModel()->currentIndex();
QString selectedText = index.data(Qt::DisplayRole).toString();
// find out the hierarchy level of the selected item
int hierarchyLevel = 1;
QModelIndex seekRoot = index;
while (seekRoot.parent().isValid()) {
seekRoot = seekRoot.parent();
hierarchyLevel++;
}
QString showString = QString("%1, Level %2").arg(selectedText)
.arg(hierarchyLevel);
setWindowTitle(showString);
}
//! [quoting modelview_b]
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