Qt : 创建对话框（2）— 创建可扩展对话框

先上效果图。我们要实现的就是在点击More之后对话框呈现下图的扩展状态，再次点击会收回第一张图片的效果。

==》界面设置部分不过多赘述。请参考下图文及简单说明。

代码如下：

/********************************************************************************
** Form generated from reading UI file 'sortdialog.ui'
**
** Created by: Qt User Interface Compiler version 5.4.2
**
** WARNING! All changes made in this file will be lost when recompiling UI file!
********************************************************************************/

#ifndef UI_SORTDIALOG_H
#define UI_SORTDIALOG_H

#include <QtCore/QVariant>
#include <QtWidgets/QAction>
#include <QtWidgets/QApplication>
#include <QtWidgets/QButtonGroup>
#include <QtWidgets/QComboBox>
#include <QtWidgets/QDialog>
#include <QtWidgets/QGridLayout>
#include <QtWidgets/QGroupBox>
#include <QtWidgets/QHeaderView>
#include <QtWidgets/QLabel>
#include <QtWidgets/QPushButton>
#include <QtWidgets/QSpacerItem>
#include <QtWidgets/QVBoxLayout>

QT_BEGIN_NAMESPACE

class Ui_SortDialog
{
public:
    QGridLayout *gridLayout_4;
    QGroupBox *primarygroupBox;
    QGridLayout *gridLayout;
    QLabel *label;
    QComboBox *primarycolumncomboBox;
    QSpacerItem *horizontalSpacer;
    QLabel *label_2;
    QComboBox *primaryordercomboBox;
    QVBoxLayout *verticalLayout;
    QPushButton *okButton;
    QPushButton *CancelButton;
    QSpacerItem *verticalSpacer;
    QPushButton *moreButton;
    QGroupBox *secondarygroupBox;
    QGridLayout *gridLayout_2;
    QLabel *label_3;
    QComboBox *secondarycolumncomboBox;
    QSpacerItem *horizontalSpacer_2;
    QLabel *label_4;
    QComboBox *secondaryordercomboBox;
    QGroupBox *tertiarygroupBox;
    QGridLayout *gridLayout_3;
    QLabel *label_5;
    QComboBox *tertialycolumncomboBox;
    QSpacerItem *horizontalSpacer_3;
    QLabel *label_6;
    QComboBox *tertiaryordercomboBox;
    QSpacerItem *verticalSpacer_2;

    void setupUi(QDialog *SortDialog)
    {
        if (SortDialog->objectName().isEmpty())
            SortDialog->setObjectName(QStringLiteral("SortDialog"));
        SortDialog->resize(337, 467);
        gridLayout_4 = new QGridLayout(SortDialog);
        gridLayout_4->setSpacing(6);
        gridLayout_4->setContentsMargins(11, 11, 11, 11);
        gridLayout_4->setObjectName(QStringLiteral("gridLayout_4"));
        primarygroupBox = new QGroupBox(SortDialog);
        primarygroupBox->setObjectName(QStringLiteral("primarygroupBox"));
        gridLayout = new QGridLayout(primarygroupBox);
        gridLayout->setSpacing(6);
        gridLayout->setContentsMargins(11, 11, 11, 11);
        gridLayout->setObjectName(QStringLiteral("gridLayout"));
        label = new QLabel(primarygroupBox);
        label->setObjectName(QStringLiteral("label"));

        gridLayout->addWidget(label, 0, 0, 1, 1);

        primarycolumncomboBox = new QComboBox(primarygroupBox);
        primarycolumncomboBox->setObjectName(QStringLiteral("primarycolumncomboBox"));

        gridLayout->addWidget(primarycolumncomboBox, 0, 1, 1, 1);

        horizontalSpacer = new QSpacerItem(29, 20, QSizePolicy::Expanding, QSizePolicy::Minimum);

        gridLayout->addItem(horizontalSpacer, 0, 2, 1, 1);

        label_2 = new QLabel(primarygroupBox);
        label_2->setObjectName(QStringLiteral("label_2"));

        gridLayout->addWidget(label_2, 1, 0, 1, 1);

        primaryordercomboBox = new QComboBox(primarygroupBox);
        primaryordercomboBox->setObjectName(QStringLiteral("primaryordercomboBox"));

        gridLayout->addWidget(primaryordercomboBox, 1, 1, 1, 2);


        gridLayout_4->addWidget(primarygroupBox, 0, 0, 1, 1);

        verticalLayout = new QVBoxLayout();
        verticalLayout->setSpacing(6);
        verticalLayout->setObjectName(QStringLiteral("verticalLayout"));
        okButton = new QPushButton(SortDialog);
        okButton->setObjectName(QStringLiteral("okButton"));
        okButton->setEnabled(true);

        verticalLayout->addWidget(okButton);

        CancelButton = new QPushButton(SortDialog);
        CancelButton->setObjectName(QStringLiteral("CancelButton"));
        CancelButton->setEnabled(false);

        verticalLayout->addWidget(CancelButton);

        verticalSpacer = new QSpacerItem(20, 13, QSizePolicy::Minimum, QSizePolicy::Expanding);

        verticalLayout->addItem(verticalSpacer);

        moreButton = new QPushButton(SortDialog);
        moreButton->setObjectName(QStringLiteral("moreButton"));
        moreButton->setEnabled(true);

        verticalLayout->addWidget(moreButton);


        gridLayout_4->addLayout(verticalLayout, 0, 1, 2, 1);

        secondarygroupBox = new QGroupBox(SortDialog);
        secondarygroupBox->setObjectName(QStringLiteral("secondarygroupBox"));
        gridLayout_2 = new QGridLayout(secondarygroupBox);
        gridLayout_2->setSpacing(6);
        gridLayout_2->setContentsMargins(11, 11, 11, 11);
        gridLayout_2->setObjectName(QStringLiteral("gridLayout_2"));
        label_3 = new QLabel(secondarygroupBox);
        label_3->setObjectName(QStringLiteral("label_3"));

        gridLayout_2->addWidget(label_3, 0, 0, 1, 1);

        secondarycolumncomboBox = new QComboBox(secondarygroupBox);
        secondarycolumncomboBox->setObjectName(QStringLiteral("secondarycolumncomboBox"));

        gridLayout_2->addWidget(secondarycolumncomboBox, 0, 1, 1, 1);

        horizontalSpacer_2 = new QSpacerItem(54, 20, QSizePolicy::Expanding, QSizePolicy::Minimum);

        gridLayout_2->addItem(horizontalSpacer_2, 0, 2, 1, 1);

        label_4 = new QLabel(secondarygroupBox);
        label_4->setObjectName(QStringLiteral("label_4"));

        gridLayout_2->addWidget(label_4, 1, 0, 1, 1);

        secondaryordercomboBox = new QComboBox(secondarygroupBox);
        secondaryordercomboBox->setObjectName(QStringLiteral("secondaryordercomboBox"));

        gridLayout_2->addWidget(secondaryordercomboBox, 1, 1, 1, 2);


        gridLayout_4->addWidget(secondarygroupBox, 2, 0, 1, 1);

        tertiarygroupBox = new QGroupBox(SortDialog);
        tertiarygroupBox->setObjectName(QStringLiteral("tertiarygroupBox"));
        gridLayout_3 = new QGridLayout(tertiarygroupBox);
        gridLayout_3->setSpacing(6);
        gridLayout_3->setContentsMargins(11, 11, 11, 11);
        gridLayout_3->setObjectName(QStringLiteral("gridLayout_3"));
        label_5 = new QLabel(tertiarygroupBox);
        label_5->setObjectName(QStringLiteral("label_5"));

        gridLayout_3->addWidget(label_5, 0, 0, 1, 1);

        tertialycolumncomboBox = new QComboBox(tertiarygroupBox);
        tertialycolumncomboBox->setObjectName(QStringLiteral("tertialycolumncomboBox"));

        gridLayout_3->addWidget(tertialycolumncomboBox, 0, 1, 1, 1);

        horizontalSpacer_3 = new QSpacerItem(54, 20, QSizePolicy::Expanding, QSizePolicy::Minimum);

        gridLayout_3->addItem(horizontalSpacer_3, 0, 2, 1, 1);

        label_6 = new QLabel(tertiarygroupBox);
        label_6->setObjectName(QStringLiteral("label_6"));

        gridLayout_3->addWidget(label_6, 1, 0, 1, 1);

        tertiaryordercomboBox = new QComboBox(tertiarygroupBox);
        tertiaryordercomboBox->setObjectName(QStringLiteral("tertiaryordercomboBox"));

        gridLayout_3->addWidget(tertiaryordercomboBox, 1, 1, 1, 2);


        gridLayout_4->addWidget(tertiarygroupBox, 3, 0, 1, 1);

        verticalSpacer_2 = new QSpacerItem(20, 9, QSizePolicy::Minimum, QSizePolicy::Expanding);

        gridLayout_4->addItem(verticalSpacer_2, 1, 0, 1, 1);

        QWidget::setTabOrder(primarycolumncomboBox, primaryordercomboBox);
        QWidget::setTabOrder(primaryordercomboBox, secondarycolumncomboBox);
        QWidget::setTabOrder(secondarycolumncomboBox, secondaryordercomboBox);
        QWidget::setTabOrder(secondaryordercomboBox, tertialycolumncomboBox);
        QWidget::setTabOrder(tertialycolumncomboBox, tertiaryordercomboBox);
        QWidget::setTabOrder(tertiaryordercomboBox, okButton);
        QWidget::setTabOrder(okButton, CancelButton);
        QWidget::setTabOrder(CancelButton, moreButton);

        retranslateUi(SortDialog);
        QObject::connect(okButton, SIGNAL(clicked()), SortDialog, SLOT(accept()));
        QObject::connect(CancelButton, SIGNAL(clicked()), SortDialog, SLOT(reject()));
        QObject::connect(moreButton, SIGNAL(toggled(bool)), secondarygroupBox, SLOT(setVisible(bool)));
        QObject::connect(moreButton, SIGNAL(toggled(bool)), tertiarygroupBox, SLOT(setVisible(bool)));

        QMetaObject::connectSlotsByName(SortDialog);
    } // setupUi

    void retranslateUi(QDialog *SortDialog)
    {
        SortDialog->setWindowTitle(QApplication::translate("SortDialog", "SortDialog", 0));
        primarygroupBox->setTitle(QApplication::translate("SortDialog", "&Primary Key", 0));
        label->setText(QApplication::translate("SortDialog", "Coloumn:", 0));
        primarycolumncomboBox->clear();
        primarycolumncomboBox->insertItems(0, QStringList()
                                           << QApplication::translate("SortDialog", "none", 0)
                                           );
        label_2->setText(QApplication::translate("SortDialog", "Order:", 0));
        primaryordercomboBox->clear();
        primaryordercomboBox->insertItems(0, QStringList()
                                          << QApplication::translate("SortDialog", "Ascending", 0)
                                          << QApplication::translate("SortDialog", "Descending", 0)
                                          );
        okButton->setText(QApplication::translate("SortDialog", "OK", 0));
        CancelButton->setText(QApplication::translate("SortDialog", "Cancel", 0));
        moreButton->setText(QApplication::translate("SortDialog", "&More", 0));
        secondarygroupBox->setTitle(QApplication::translate("SortDialog", "&Secondary Key", 0));
        label_3->setText(QApplication::translate("SortDialog", "Coloumn:", 0));
        secondarycolumncomboBox->clear();
        secondarycolumncomboBox->insertItems(0, QStringList()
                                             << QApplication::translate("SortDialog", "none", 0)
                                             );
        label_4->setText(QApplication::translate("SortDialog", "Order:", 0));
        secondaryordercomboBox->clear();
        secondaryordercomboBox->insertItems(0, QStringList()
                                            << QApplication::translate("SortDialog", "Ascending", 0)
                                            << QApplication::translate("SortDialog", "Descending", 0)
                                            );
        tertiarygroupBox->setTitle(QApplication::translate("SortDialog", "&Tertiary Key", 0));
        label_5->setText(QApplication::translate("SortDialog", "Coloumn:", 0));
        tertialycolumncomboBox->clear();
        tertialycolumncomboBox->insertItems(0, QStringList()
                                            << QApplication::translate("SortDialog", "none", 0)
                                            );
        label_6->setText(QApplication::translate("SortDialog", "Order:", 0));
        tertiaryordercomboBox->clear();
        tertiaryordercomboBox->insertItems(0, QStringList()
                                           << QApplication::translate("SortDialog", "Ascending", 0)
                                           << QApplication::translate("SortDialog", "Descending", 0)
                                           );
    } // retranslateUi

};

namespace Ui {
class SortDialog: public Ui_SortDialog {};
} // namespace Ui

QT_END_NAMESPACE

#endif // UI_SORTDIALOG_H

#ifndef SORTDIALOG_H
#define SORTDIALOG_H

#include <QDialog>
#include"QChar"
namespace Ui {
class SortDialog;
}

class SortDialog : public QDialog
{
    Q_OBJECT

public:
    explicit SortDialog(QWidget *parent = 0);
    ~SortDialog();
    void setColumnRange(QChar first,QChar last);
private slots:
    void on_moreButton_clicked();

private:
    Ui::SortDialog *ui;
private:
    bool flag;
};

#endif // SORTDIALOG_H

#include "sortdialog.h"
#include "ui_sortdialog.h"

SortDialog::SortDialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::SortDialog)
{
    ui->setupUi(this);
    ui->secondarygroupBox->hide();
    ui->tertiarygroupBox->hide();
    layout()->setSizeConstraint(QLayout::SetFixedSize);
    setColumnRange('A','Z');

    flag = false;
}

SortDialog::~SortDialog()
{
    delete ui;
}
void SortDialog::setColumnRange(QChar first,QChar last)
{
    ui->primarycolumncomboBox->clear();
    ui->secondarycolumncomboBox->clear();
    ui->tertialycolumncomboBox->clear();

    ui->secondarycolumncomboBox->addItem(tr("none"));
    ui->tertialycolumncomboBox->addItem(tr("none"));
    ui->primarycolumncomboBox->setMinimumSize(ui->secondarycolumncomboBox->sizeHint());

    QChar ch =first;
    while(ch <= last)
    {
        ui->primarycolumncomboBox->addItem(QString(ch));
        ui->secondarycolumncomboBox->addItem(QString(ch));
        ui->tertialycolumncomboBox->addItem(QString(ch));
        ch = ch.unicode() +1;
    }
}

void SortDialog::on_moreButton_clicked()
{
    flag = !flag;
    if(flag){
    ui->secondarygroupBox->show();
    ui->tertiarygroupBox->show();
    }
    else
    {
        ui->secondarygroupBox->hide();
        ui->tertiarygroupBox->hide();
    }
}