C++/Qt/QVector
Содержание
Copying Container Areas
#include <QStringList>
#include <QVector>
#include <QDebug>
int main()
{
QStringList list;
list << "one" << "two" << "three";
QVector<QString> vect(list.size());
qCopy(list.begin(), list.end(), vect.begin());
qDebug() << vect; // output: ( "one", "two", "three" )
return 0;
}
creates two containers and compares all the elements for equality:
#include <QStringList>
#include <QVector>
#include <QDebug>
int main()
{
QStringList list;
list << "one" << "two" << "three";
QVector<QString> vect(3);
vect[0] = "one";
vect[1] = "two";
vect[2] = "three";
bool ret = qEqual(list.begin(), list.end(), vect.begin());
qDebug() << ret; // output: true
return 0;
}
Store QPoint in QVector
Foundations of Qt Development\Chapter07\drawlines\main.cpp
/*
* Copyright (c) 2006-2007, Johan Thelin
*
* All rights reserved.
*
* 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 APress 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.
*
*/
#include <QApplication>
#include <QPixmap>
#include <QPainter>
int main( int argc, char **argv )
{
QApplication app( argc, argv );
QPixmap pixmap( 200, 100 );
pixmap.fill( Qt::white );
QPainter painter( &pixmap );
painter.setPen( Qt::black );
QVector<QPoint> polyPoints;
polyPoints << QPoint( 60, 10 ) << QPoint( 80, 90 ) << QPoint( 75, 10 ) << QPoint( 110, 90 );
QVector<QPoint> linePoints;
foreach( QPoint point, polyPoints )
linePoints << point + QPoint( 80, 0 );
painter.drawLine( QPoint( 10, 10 ), QPoint( 30, 90 ) );
painter.drawPolyline( polyPoints );
painter.drawLines( linePoints );
pixmap.save( "drawlines.png" );
return 0;
}
Using QVector
#include <QVector>
#include <QDebug>
int main()
{
const int n = 10;
QVector<int> vector(n);
int * data = vector.data();
for (int i = 0; i < n; ++i)
data[i] = i;
for (int i = 0; i < n; ++i) {
data[i] * = 2;
qDebug() << vector.at(i);
}
QVector<QString> strvector;
strvector.append("s");
if (strvector[0] == "s")
strvector[0] = "868686876";
qDebug() << strvector;
return 0;
}