qmessagebox

    QColor color = QColorDialog::getColor(Qt::red,this,tr("颜色对话框"),QColorDialog::ShowAlphaChannel);

    QColorDialog dialog(Qt::red,this);
    dialog.setOption(QColorDialog::ShowAlphaChannel);
    dialog.exec();
    QColor color = dialog.currentColor();

currentColor：This property holds the currently selected color in the dialog.

    QString filename = QFileDialog::getOpenFileName(this,"文件对话框","D:","Images (*.png *.jpg);;code (*.cpp);;header (*.h)");

多个文件过滤器用;;   单个过滤器要用空格隔开，不然就变成一个filter.

       bool ok;

    QString string = QInputDialog::getText(this,tr("字符输入"),tr("输入"),QLineEdit::Normal,"text",&ok);

    if(ok)

    {

        qDebug()<<"string"<<string;

    }

    int i = QInputDialog::getInt(this,"get int","input",0,0,12,1,&ok);

    if(ok)

    {

        qDebug()<<"i"<<i;

    }

    QStringList item;

    item<<"1"<<"2";

    QString list = QInputDialog::getItem(this,"item_get","input",item,1,false,&ok);

    int back = QMessageBox::question(this,"hahah","hahaha",QMessageBox::Ok,QMessageBox::No);
    if(back == QMessageBox::Ok)
    {
        qDebug()<<"well";
    }

    back = QMessageBox::information(this,"ha","ha",QMessageBox::Ok,QMessageBox::No);
    if(back == QMessageBox::Ok)
    {
        qDebug()<<"well";
    }

    QMessageBox::warning(this,"ok?","hah",QMessageBox::Ok,QMessageBox::Abort);

    QMessageBox::critical(this,"ok?","hah",QMessageBox::YesAll,QMessageBox::Abort);

    QProgressDialog bar("haha","cancel",0,500000,this);
    bar.setWindowTitle("dialog for progress");
    bar.setWindowModality(Qt::WindowModal);
    bar.show();

    for(int i = 0; i <500001; i++)
    {
        bar.setValue(i);
        if(bar.wasCanceled())break;
    }

    QErrorMessage *error = new QErrorMessage(this);
    error->setWindowTitle("error");
    error->showMessage("wrong");

    QWizardPage *page1 = new QWizardPage;
    QWizardPage *page2 = new QWizardPage;
    QWizardPage *page3 = new QWizardPage;
    page1->setWindowTitle("introduce");
    page2->setWindowTitle("choose");
    page3->setWindowTitle("exit");

    QWizard wizard(this);
    wizard.addPage(page1);
    wizard.addPage(page2);
    wizard.addPage(page3);
    wizard.setWindowTitle("wizard");
    wizard.exec();