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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
** of its contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QCoreApplication>
#include <QLoggingCategory>
//![1]
// in a header
Q_DECLARE_LOGGING_CATEGORY(QT_DRIVER_USB)
// in one source file
Q_LOGGING_CATEGORY(QT_DRIVER_USB, "qt.driver.usb")
//![1]
// Completely made up example, inspired by en.wikipedia.org/wiki/USB :)
struct UsbEntry {
int id;
int classtype;
};
QDebug operator<<(QDebug &dbg, const UsbEntry &entry)
{
dbg.nospace() << "" << entry.id << " (" << entry.classtype << ")";
return dbg.space();
}
QList<UsbEntry> usbEntries() {
QList<UsbEntry> entries;
return entries;
}
void main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
//![2]
// don't run the expensive code if the string won't print
if (QT_DRIVER_USB().isDebugEnabled()) {
QStringList items;
foreach (const UsbEntry &entry, usbEntries())
items << QString("%1 (%2)").arg(entry.id, entry.classtype);
qCDebug(QT_DRIVER_USB) << "devices: " << items;
}
//![2]
//![3]
// usbEntries() will only be called if QT_DRIVER_USB category is enabled
qCDebug(QT_DRIVER_USB) << "devices: " << usbEntries();
//![3]
{
//![10]
QLoggingCategory category("qt.driver.usb");
qCDebug(category) << "a debug message";
//![10]
}
{
//![11]
QLoggingCategory category("qt.driver.usb");
qCWarning(category) << "a warning message";
//![11]
}
{
//![12]
QLoggingCategory category("qt.driver.usb");
qCCritical(category) << "a critical message";
//![12]
}
}
//![20]
void myCategoryFilter(QLoggingCategory *);
//![20]
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