C++/Qt/QDirModel

Материал из C\C++ эксперт
Перейти к: навигация, поиск

Access items from an existing model

<source lang="cpp"> /****************************************************************************

    • Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
    • All rights reserved.
    • Contact: Nokia Corporation (qt-info@nokia.com)
    • This file is part of the documentation of the Qt Toolkit.
    • $QT_BEGIN_LICENSE:LGPL$
    • Commercial Usage
    • Licensees holding valid Qt Commercial licenses may use this file in
    • accordance with the Qt Commercial License Agreement provided with the
    • Software or, alternatively, in accordance with the terms contained in
    • a written agreement between you and Nokia.
    • GNU Lesser General Public License Usage
    • Alternatively, this file may be used under the terms of the GNU Lesser
    • General Public License version 2.1 as published by the Free Software
    • Foundation and appearing in the file LICENSE.LGPL included in the
    • packaging of this file. Please review the following information to
    • ensure the GNU Lesser General Public License version 2.1 requirements
    • will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
    • In addition, as a special exception, Nokia gives you certain additional
    • rights. These rights are described in the Nokia Qt LGPL Exception
    • version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
    • GNU General Public License Usage
    • Alternatively, this file may be used under the terms of the GNU
    • General Public License version 3.0 as published by the Free Software
    • Foundation and appearing in the file LICENSE.GPL included in the
    • packaging of this file. Please review the following information to
    • ensure the GNU General Public License version 3.0 requirements will be
    • met: http://www.gnu.org/copyleft/gpl.html.
    • If you have questions regarding the use of this file, please contact
    • Nokia at qt-info@nokia.com.
    • $QT_END_LICENSE$
                                                                                                                                                        • /

/*

 main.cpp
 A simple example of how to access items from an existing model.
  • /
  1. include <QtGui>

/*!

   Create a default directory model and, using the index-based interface to
   the model and some QLabel widgets, populate the window"s layout with the
   names of objects in the directory.
   Note that we only want to read the filenames in the highest level of the
   directory, so we supply a default (invalid) QModelIndex to the model in
   order to indicate that we want top-level items.
  • /

int main(int argc, char *argv[]) {

   QApplication app(argc, argv);
   QWidget *window = new QWidget;
   QVBoxLayout *layout = new QVBoxLayout(window);
   QLabel *title = new QLabel("Some items from the directory model", window);
   title->setBackgroundRole(QPalette::Base);
   title->setMargin(8);
   layout->addWidget(title);
   
   QDirModel *model = new QDirModel;
   QModelIndex parentIndex = model->index(QDir::currentPath());
   int numRows = model->rowCount(parentIndex);
   for (int row = 0; row < numRows; ++row) {
       QModelIndex index = model->index(row, 0, parentIndex);
       QString text = model->data(index, Qt::DisplayRole).toString();
       // Display the text in a widget.
       QLabel *label = new QLabel(text, window);
       layout->addWidget(label);
   }
   window->setWindowTitle("A simple model example");
   window->show();
   return app.exec();

}


 </source>