c++ - 如何从QWizardPage和访问field()运行QThread

我需要一些建议，以便从QString name访问QWizardPage中的field(QThread)变量。我正在构建某种安装程序，我想在单独的线程中进行安装工作。

我的目的:
到达提交/安装页面时，我想执行代码以进行“安装”并用进度更新QWizardPage，直到完成为止。

安装功能取决于其他field()中的许多QWizardPages变量。因此，我尝试从QThread执行此安装功能，该功能在QWizardPage的内部类中定义。问题是field() -function我是一个非静态成员，因此无法正常工作。因此，我无法将安装功能与WizardPage并行运行。

我尝试过这样的事情:

InstallPage.h

class InstallPage : public QWizardPage
{
    Q_OBJECT
    class WorkerThread : public QThread
    {
        Q_OBJECT
        void run() override;
    };

public:
    InstallPage(QWidget *parent = 0);

private:
    QLabel *lProgress;
    WorkerThread *installer;
    void install();
};


InstallPage.c

InstallPage::InstallPage(QWidget *parent)
    : QWizardPage(parent)
{
...
    installer = new WorkerThread(this);
    installer->start();
}

void InstallPage::WorkerThread::run()
{
    if(field("checkBox1").ToBool())
    {
         doStuff();
    }
}

//QT-Creator says at field("checkBox1"):
//error: call to non-static member function without an object argument

我也乐于接受任何其他想法来使我的安装程序正常工作。也许有人知道我没想到的事。

最佳答案

另一种方法是创建一个工作器(QObject)，该工作器位于另一个执行繁重任务并通过信号通知该任务状态的线程中:

#include <QtWidgets>

class InitialPage: public QWizardPage
{
public:
    InitialPage(QWidget *parent = nullptr): QWizardPage(parent)
    {
        QSpinBox *spinbox = new QSpinBox;
        QLineEdit *lineedit = new QLineEdit;
        QVBoxLayout *lay = new QVBoxLayout(this);
        lay->addWidget(spinbox);
        lay->addWidget(lineedit);

        registerField("value1", spinbox);
        registerField("value2", lineedit);
    }

};

class InstallWorker: public QObject
{
    Q_OBJECT
public:
    InstallWorker(QObject *parent=nullptr): QObject(parent)
    {

    }
public Q_SLOTS:
    void install(int param1, const QString & param2)
    {
        Q_EMIT started();
        for(int i=0; i < 100; i++){
            qDebug() << __PRETTY_FUNCTION__ << i << param1 << param2;
            QThread::msleep(100);
            Q_EMIT progressChanged(i);
        }
        qDebug()<< __PRETTY_FUNCTION__ << "finished";
        Q_EMIT finished();
    }
Q_SIGNALS:
    void started();
    void progressChanged(int value);
    void finished();
};

class InstallPage: public QWizardPage
{
    Q_OBJECT
public:
    InstallPage(QWidget *parent = nullptr): QWizardPage(parent),
        label(new QLabel), progressbar(new QProgressBar)
    {

        QVBoxLayout *lay = new QVBoxLayout(this);
        lay->addWidget(label);
        lay->addWidget(progressbar);

        progressbar->setMinimum(0);
        progressbar->setMaximum(100);

        thread = new QThread(this);
        worker.moveToThread(thread);
        connect(&worker, &InstallWorker::started, this, &InstallPage::onStarted);
        connect(&worker, &InstallWorker::finished, this, &InstallPage::onFinished);
        connect(&worker, &InstallWorker::progressChanged, this, &InstallPage::onProgressChanged);
        thread->start();
    }
    ~InstallPage(){
        thread->quit();
        thread->wait();
    }
    void initializePage(){
        start_install();
    }
private Q_SLOTS:
    void start_install(){
        int param1 = field("value1").toInt();;
        QString param2 = field("value2").toString();
        QMetaObject::invokeMethod(&worker, "install", Qt::QueuedConnection, Q_ARG(int, param1), Q_ARG(QString, param2));
    }
    void onStarted(){
        for(QWizard::WizardButton which: {QWizard::BackButton, QWizard::NextButton, QWizard::CancelButton})
            if(QAbstractButton * button = wizard()->button(which))
                button->setEnabled(false);
    }
    void onFinished(){
        for(QWizard::WizardButton which: {QWizard::BackButton, QWizard::NextButton, QWizard::CancelButton})
            if(QAbstractButton * button = wizard()->button(which))
                button->setEnabled(true);
        wizard()->next();
    }
    void onProgressChanged(int value){
        progressbar->setValue(value);
        label->setNum(value);
    }
private:
    InstallWorker worker;
    QThread *thread;
    QLabel *label;
    QProgressBar *progressbar;
};

class FinalPage: public QWizardPage
{
public:
    FinalPage(QWidget *parent = nullptr): QWizardPage(parent)
    {

    }
};

#include "main.moc"

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWizard wizard;
    wizard.addPage(new InitialPage);
    wizard.addPage(new InstallPage);
    wizard.addPage(new FinalPage);
    wizard.show();
    return app.exec();
}