Simple Text Viewer Example

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#include "assistant.h"

#include <QByteArray>
#include <QDir>
#include <QLibraryInfo>
#include <QMessageBox>
#include <QProcess>

Assistant::Assistant()
    : proc(0)
{
}

Assistant::~Assistant()
{
    if (proc && proc->state() == QProcess::Running) {
        proc->terminate();
        proc->waitForFinished(3000);
    }
    delete proc;
}

void Assistant::showDocumentation(const QString &page)
{
    if (!startAssistant())
        return;

    QByteArray ba("SetSource ");
    ba.append("qthelp://org.qt-project.examples.simpletextviewer/doc/");

    proc->write(ba + page.toLocal8Bit() + '\n');
}

bool Assistant::startAssistant()
{
    if (!proc)
        proc = new QProcess();

    if (proc->state() != QProcess::Running) {
        QString app = QLibraryInfo::location(QLibraryInfo::BinariesPath) + QDir::separator();
#if !defined(Q_OS_MAC)
        app += QLatin1String("assistant");
#else
        app += QLatin1String("Assistant.app/Contents/MacOS/Assistant");
#endif

        QStringList args;
        args << QLatin1String("-collectionFile")
            << QLibraryInfo::location(QLibraryInfo::ExamplesPath)
            + QLatin1String("/assistant/simpletextviewer/documentation/simpletextviewer.qhc")
            << QLatin1String("-enableRemoteControl");

        proc->start(app, args);

        if (!proc->waitForStarted()) {
            QMessageBox::critical(nullptr,
                                  tr("Simple Text Viewer"),
                                  tr("Unable to launch Qt Assistant (%1)").arg(app));
            return false;
        }
    }
    return true;
}