C++/Qt/QList
Содержание
Add int to QList
#include <QtCore>
#include <QDebug>
int main() {
QList<int> intlist;
intlist << 2 << 5 << 2 << 4 << 2;
int findings = 0;
QListIterator<int> it(intlist);
while (it.findNext(2))
findings++;
qDebug() << findings; // output: 3
while (it.findPrevious(2))
findings--;
qDebug() << findings; // : 0
return 0;
}
Append and insert into QList
/*
* 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 <QList>
#include <QString>
#include <QtDebug>
void fillAndPrint()
{
QList<QString> list;
list << "foo" << "bar" << "baz";
QString s;
foreach( s, list )
qDebug() << s;
}
void constIterators()
{
QList<int> list;
list << 23 << 27 << 52 << 52;
QListIterator<int> javaIter( list );
while( javaIter.hasNext() )
qDebug() << javaIter.next();
QList<int>::const_iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
qDebug() << (*stlIter);
}
void mutableIterators()
{
QList<int> list;
list << 27 << 33 << 61 << 62;
QMutableListIterator<int> javaIter( list );
while( javaIter.hasNext() )
{
int value = javaIter.next() + 1;
javaIter.setValue( value );
qDebug() << value;
}
QList<int>::Iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
{
(*stlIter) = (*stlIter)*2;
qDebug() << (*stlIter);
}
}
void insertAndPrint()
{
QList<QString> list;
list << "first";
list.append( "second" );
list.prepend( "third" );
list.insert( 1, "fourth" );
list.insert( 4, "fifth" );
QString s;
foreach( s, list )
qDebug() << s;
}
void miscExamples()
{
QList<int> list;
for( int i=0; i<10; i++ )
list << i;
int sum = list[5] + list.at(7);
}
int main( void )
{
qDebug() << "Fill and print";
fillAndPrint();
qDebug() << "Const iterators";
constIterators();
qDebug() << "Mutable iterators";
mutableIterators();
qDebug() << "Insert and print";
insertAndPrint();
return 0;
}
Delete all elements in a QList
#include <QtGui>
#include <QDebug>
int main(int argc, char * argv[]) {
QApplication app(argc, argv);
QList<QWidget* > widgetList;
for (int i = 1; i < 10; i++)
{
widgetList.append(new QWidget);
}
qDeleteAll(widgetList.begin(), widgetList.end());
widgetList.clear();
widgetList.append(new QWidget);
return 0;
}
Filling Data Structures
#include <QList>
#include <QDebug>
int main()
{
QList<int> values;
values << 1 << 4 << 7 << 9;
qFill(values.begin(), values.end(), 0);
qDebug() << values; // output: ( 0, 0, 0, 0 )
return 0;
}
Find next element in a QList with QMutableListIterator
#include <QtCore>
#include <QDebug>
int main() {
QList<int> intlist;
intlist << 2 << 5 << 2 << 4 << 2;
QMutableListIterator<int> mit(intlist);
while (mit.findNext(2))
mit.remove();
qDebug() << intlist; // output: (5, 4)
return 0;
}
Foreach loop with QList
/*
* 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 <QList>
#include <QString>
#include <QtDebug>
void fillAndPrint()
{
QList<QString> list;
list << "foo" << "bar" << "baz";
QString s;
foreach( s, list )
qDebug() << s;
}
void constIterators()
{
QList<int> list;
list << 23 << 27 << 52 << 52;
QListIterator<int> javaIter( list );
while( javaIter.hasNext() )
qDebug() << javaIter.next();
QList<int>::const_iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
qDebug() << (*stlIter);
}
void mutableIterators()
{
QList<int> list;
list << 27 << 33 << 61 << 62;
QMutableListIterator<int> javaIter( list );
while( javaIter.hasNext() )
{
int value = javaIter.next() + 1;
javaIter.setValue( value );
qDebug() << value;
}
QList<int>::Iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
{
(*stlIter) = (*stlIter)*2;
qDebug() << (*stlIter);
}
}
void insertAndPrint()
{
QList<QString> list;
list << "first";
list.append( "second" );
list.prepend( "third" );
list.insert( 1, "fourth" );
list.insert( 4, "fifth" );
QString s;
foreach( s, list )
qDebug() << s;
}
void miscExamples()
{
QList<int> list;
for( int i=0; i<10; i++ )
list << i;
int sum = list[5] + list.at(7);
}
int main( void )
{
qDebug() << "Fill and print";
fillAndPrint();
qDebug() << "Const iterators";
constIterators();
qDebug() << "Mutable iterators";
mutableIterators();
qDebug() << "Insert and print";
insertAndPrint();
return 0;
}
QList of int
/*
* 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 <QList>
#include <QString>
#include <QtDebug>
void fillAndPrint()
{
QList<QString> list;
list << "foo" << "bar" << "baz";
QString s;
foreach( s, list )
qDebug() << s;
}
void constIterators()
{
QList<int> list;
list << 23 << 27 << 52 << 52;
QListIterator<int> javaIter( list );
while( javaIter.hasNext() )
qDebug() << javaIter.next();
QList<int>::const_iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
qDebug() << (*stlIter);
}
void mutableIterators()
{
QList<int> list;
list << 27 << 33 << 61 << 62;
QMutableListIterator<int> javaIter( list );
while( javaIter.hasNext() )
{
int value = javaIter.next() + 1;
javaIter.setValue( value );
qDebug() << value;
}
QList<int>::Iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
{
(*stlIter) = (*stlIter)*2;
qDebug() << (*stlIter);
}
}
void insertAndPrint()
{
QList<QString> list;
list << "first";
list.append( "second" );
list.prepend( "third" );
list.insert( 1, "fourth" );
list.insert( 4, "fifth" );
QString s;
foreach( s, list )
qDebug() << s;
}
void miscExamples()
{
QList<int> list;
for( int i=0; i<10; i++ )
list << i;
int sum = list[5] + list.at(7);
}
int main( void )
{
qDebug() << "Fill and print";
fillAndPrint();
qDebug() << "Const iterators";
constIterators();
qDebug() << "Mutable iterators";
mutableIterators();
qDebug() << "Insert and print";
insertAndPrint();
return 0;
}
QList of QString
/*
* 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 <QList>
#include <QString>
#include <QtDebug>
void fillAndPrint()
{
QList<QString> list;
list << "foo" << "bar" << "baz";
QString s;
foreach( s, list )
qDebug() << s;
}
void constIterators()
{
QList<int> list;
list << 23 << 27 << 52 << 52;
QListIterator<int> javaIter( list );
while( javaIter.hasNext() )
qDebug() << javaIter.next();
QList<int>::const_iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
qDebug() << (*stlIter);
}
void mutableIterators()
{
QList<int> list;
list << 27 << 33 << 61 << 62;
QMutableListIterator<int> javaIter( list );
while( javaIter.hasNext() )
{
int value = javaIter.next() + 1;
javaIter.setValue( value );
qDebug() << value;
}
QList<int>::Iterator stlIter;
for( stlIter = list.begin(); stlIter != list.end(); ++stlIter )
{
(*stlIter) = (*stlIter)*2;
qDebug() << (*stlIter);
}
}
void insertAndPrint()
{
QList<QString> list;
list << "first";
list.append( "second" );
list.prepend( "third" );
list.insert( 1, "fourth" );
list.insert( 4, "fifth" );
QString s;
foreach( s, list )
qDebug() << s;
}
void miscExamples()
{
QList<int> list;
for( int i=0; i<10; i++ )
list << i;
int sum = list[5] + list.at(7);
}
int main( void )
{
qDebug() << "Fill and print";
fillAndPrint();
qDebug() << "Const iterators";
constIterators();
qDebug() << "Mutable iterators";
mutableIterators();
qDebug() << "Insert and print";
insertAndPrint();
return 0;
}
Quick sort QList
#include <QList>
#include <QtAlgorithms> // for qSort()
#include <QStringList>
#include <QDebug>
class CaseIgnoreString : public QString {
public:
CaseIgnoreString(const QString& other = QString()) : QString(other) {}
bool operator<(const QString & other) const {
return toLower() < other.toLower();
}
bool operator==(const QString& other) const {
return toLower() == other.toLower();
}
};
int main() {
CaseIgnoreString s1("A"), s2("b"), s3 ("C"), s4("d"), s5 ("D");
QList<CaseIgnoreString> namelist;
namelist << s5 << s1 << s3 << s4 << s2;
qSort(namelist.begin(), namelist.end());
int i=0;
foreach (QString stritr, namelist) {
qDebug() << QString("namelist[%1] = %2").arg(i++).arg(stritr) ;
}
QStringList strlist;
strlist << s5 << s1 << s3 << s4 << s2;
qSort(strlist.begin(), strlist.end());
qDebug() << "StringList sorted: " + strlist.join(", ") << endl;
return 0;
}
Sorting QList
#include <QList>
#include <QDebug>
int main()
{
QList<int> values;
values << 1 << 10 << 5 << 6 << 7 << 3;
qSort(values);
qDebug() << values; // output: ( 1, 3, 5, 6, 7, 10 )
return 0;
}