- Qt 5.5
- Qt Widgets
- Custom Completer Example
- mainwindow.cpp Example File
- Qt 5.5.1 Reference Documentation

# mainwindow.cpp Example File

tools/customcompleter/mainwindow.cpp

    /****************************************************************************
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    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
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    **
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    ** modification, are permitted provided that the following conditions are
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    #include <QtWidgets>
    #include "mainwindow.h"
    #include "textedit.h"

    MainWindow::MainWindow(QWidget *parent)
        : QMainWindow(parent), completer(0)
    {
        createMenu();

        completingTextEdit = new TextEdit;
        completer = new QCompleter(this);
        completer->setModel(modelFromFile(":/resources/wordlist.txt"));
        completer->setModelSorting(QCompleter::CaseInsensitivelySortedModel);
        completer->setCaseSensitivity(Qt::CaseInsensitive);
        completer->setWrapAround(false);
        completingTextEdit->setCompleter(completer);

        setCentralWidget(completingTextEdit);
        resize(500, 300);
        setWindowTitle(tr("Completer"));
    }

    void MainWindow::createMenu()
    {
        QAction *exitAction = new QAction(tr("Exit"), this);
        QAction *aboutAct = new QAction(tr("About"), this);
        QAction *aboutQtAct = new QAction(tr("About Qt"), this);

        connect(exitAction, SIGNAL(triggered()), qApp, SLOT(quit()));
        connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
        connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));

        QMenu* fileMenu = menuBar()->addMenu(tr("File"));
        fileMenu->addAction(exitAction);

        QMenu* helpMenu = menuBar()->addMenu(tr("About"));
        helpMenu->addAction(aboutAct);
        helpMenu->addAction(aboutQtAct);
    }

    QAbstractItemModel *MainWindow::modelFromFile(const QString& fileName)
    {
        QFile file(fileName);
        if (!file.open(QFile::ReadOnly))
            return new QStringListModel(completer);

    #ifndef QT_NO_CURSOR
        QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
    #endif
        QStringList words;

        while (!file.atEnd()) {
            QByteArray line = file.readLine();
            if (!line.isEmpty())
                words << line.trimmed();
        }

    #ifndef QT_NO_CURSOR
        QApplication::restoreOverrideCursor();
    #endif
        return new QStringListModel(words, completer);
    }

    void MainWindow::about()
    {
        QMessageBox::about(this, tr("About"), tr("This example demonstrates the "
            "different features of the QCompleter class."));
    }