src_corelib_tools_qlist.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
#include <QList>
#include <iostream>
#include <QDebug>
 
using namespace std;
 
void examples()
{
    {
        //! [0]
        QList<int> integerList;
        QList<QString> stringList;
        //! [0]
    }
 
    {
        //! [1]
        QList<QString> list(200);
        //! [1]
    }
 
    {
        //! [2]
        QList<QString> list(200, "Pass");
        //! [2]
    }
 
    {
        QList<QString> list;
 
        //! [3]
        if (list[0] == "Liz")
            list[0] = "Elizabeth";
        //! [3]
    }
 
    {
        QList<QString> list;
 
        //! [4]
        for (qsizetype i = 0; i < list.size(); ++i) {
            if (list.at(i) == "Alfonso")
                cout << "Found Alfonso at position " << i << endl;
        }
        //! [4]
    }
 
    {
        QList<QString> list;
 
        //! [5]
        qsizetype i = list.indexOf("Harumi");
        if (i != -1)
            cout << "First occurrence of Harumi is at position " << i << endl;
        //! [5]
    }
 
    {
        //! [6]
        QList<int> list(10);
        int *data = list.data();
        for (qsizetype i = 0; i < 10; ++i)
            data[i] = 2 * i;
        //! [6]
    }
 
    {
        //! [7]
        QList<QString> list;
        list.append("one");
        list.append("two");
        QString three = "three";
        list.append(three);
        // list: ["one", "two", "three"]
        // three: "three"
        //! [7]
    }
 
    {
        //! [move-append]
        QList<QString> list;
        list.append("one");
        list.append("two");
        QString three = "three";
        list.append(std::move(three));
        // list: ["one", "two", "three"]
        // three: ""
        //! [move-append]
    }
 
    {
        //! [emplace]
        QList<QString> list{"a", "ccc"};
        list.emplace(1, 2, 'b');
        // list: ["a", "bb", "ccc"]
        //! [emplace]
    }
 
    {
        //! [emplace-back]
        QList<QString> list{"one", "two"};
        list.emplaceBack(3, 'a');
        qDebug() << list;
        // list: ["one", "two", "aaa"]
        //! [emplace-back]
    }
 
    {
        //! [emplace-back-ref]
        QList<QString> list;
        auto &ref = list.emplaceBack();
        ref = "one";
        // list: ["one"]
        //! [emplace-back-ref]
    }
 
    {
        //! [8]
        QList<QString> list;
        list.prepend("one");
        list.prepend("two");
        list.prepend("three");
        // list: ["three", "two", "one"]
        //! [8]
    }
 
    {
        //! [9]
        QList<QString> list = {"alpha", "beta", "delta"};
        list.insert(2, "gamma");
        // list: ["alpha", "beta", "gamma", "delta"]
        //! [9]
    }
 
    {
        //! [10]
        QList<double> list = {2.718, 1.442, 0.4342};
        list.insert(1, 3, 9.9);
        // list: [2.718, 9.9, 9.9, 9.9, 1.442, 0.4342]
        //! [10]
    }
 
    {
        //! [11]
        QList<QString> list(3);
        list.fill("Yes");
        // list: ["Yes", "Yes", "Yes"]
 
        list.fill("oh", 5);
        // list: ["oh", "oh", "oh", "oh", "oh"]
        //! [11]
    }
 
    {
        //! [12]
        QList<QString> list{"A", "B", "C", "B", "A"};
        list.indexOf("B");            // returns 1
        list.indexOf("B", 1);         // returns 1
        list.indexOf("B", 2);         // returns 3
        list.indexOf("X");            // returns -1
        //! [12]
    }
 
    {
        //! [13]
        QList<QString> list = {"A", "B", "C", "B", "A"};
        list.lastIndexOf("B");        // returns 3
        list.lastIndexOf("B", 3);     // returns 3
        list.lastIndexOf("B", 2);     // returns 1
        list.lastIndexOf("X");        // returns -1
        //! [13]
    }
}