- Qt 5.5
- Qt Widgets
- Standard Dialogs Example
- dialog.cpp Example File
- Qt 5.5.1 Reference Documentation

# dialog.cpp Example File

dialogs/standarddialogs/dialog.cpp

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
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    #include <QtWidgets>

    #include "dialog.h"

    #define MESSAGE \
        Dialog::tr("<p>Message boxes have a caption, a text, " \
                   "and any number of buttons, each with standard or custom texts." \
                   "<p>Click a button to close the message box. Pressing the Esc button " \
                   "will activate the detected escape button (if any).")
    #define MESSAGE_DETAILS \
        Dialog::tr("If a message box has detailed text, the user can reveal it " \
                   "by pressing the Show Details... button.")

    class DialogOptionsWidget : public QGroupBox
    {
    public:
        explicit DialogOptionsWidget(QWidget *parent = 0);

        void addCheckBox(const QString &text, int value);
        void addSpacer();
        int value() const;

    private:
        typedef QPair<QCheckBox *, int> CheckBoxEntry;
        QVBoxLayout *layout;
        QList<CheckBoxEntry> checkBoxEntries;
    };

    DialogOptionsWidget::DialogOptionsWidget(QWidget *parent) :
        QGroupBox(parent) , layout(new QVBoxLayout)
    {
        setTitle(Dialog::tr("Options"));
        setLayout(layout);
    }

    void DialogOptionsWidget::addCheckBox(const QString &text, int value)
    {
        QCheckBox *checkBox = new QCheckBox(text);
        layout->addWidget(checkBox);
        checkBoxEntries.append(CheckBoxEntry(checkBox, value));
    }

    void DialogOptionsWidget::addSpacer()
    {
        layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding));
    }

    int DialogOptionsWidget::value() const
    {
        int result = 0;
        foreach (const CheckBoxEntry &checkboxEntry, checkBoxEntries)
            if (checkboxEntry.first->isChecked())
                result |= checkboxEntry.second;
        return result;
    }

    Dialog::Dialog(QWidget *parent)
        : QWidget(parent)
    {
        QVBoxLayout *mainLayout = new QVBoxLayout(this);
        QToolBox *toolbox = new QToolBox;
        mainLayout->addWidget(toolbox);

        errorMessageDialog = new QErrorMessage(this);

        int frameStyle = QFrame::Sunken | QFrame::Panel;

        integerLabel = new QLabel;
        integerLabel->setFrameStyle(frameStyle);
        QPushButton *integerButton =
                new QPushButton(tr("QInputDialog::get&Int()"));

        doubleLabel = new QLabel;
        doubleLabel->setFrameStyle(frameStyle);
        QPushButton *doubleButton =
                new QPushButton(tr("QInputDialog::get&Double()"));

        itemLabel = new QLabel;
        itemLabel->setFrameStyle(frameStyle);
        QPushButton *itemButton = new QPushButton(tr("QInputDialog::getIte&m()"));

        textLabel = new QLabel;
        textLabel->setFrameStyle(frameStyle);
        QPushButton *textButton = new QPushButton(tr("QInputDialog::get&Text()"));

        multiLineTextLabel = new QLabel;
        multiLineTextLabel->setFrameStyle(frameStyle);
        QPushButton *multiLineTextButton = new QPushButton(tr("QInputDialog::get&MultiLineText()"));

        colorLabel = new QLabel;
        colorLabel->setFrameStyle(frameStyle);
        QPushButton *colorButton = new QPushButton(tr("QColorDialog::get&Color()"));

        fontLabel = new QLabel;
        fontLabel->setFrameStyle(frameStyle);
        QPushButton *fontButton = new QPushButton(tr("QFontDialog::get&Font()"));

        directoryLabel = new QLabel;
        directoryLabel->setFrameStyle(frameStyle);
        QPushButton *directoryButton =
                new QPushButton(tr("QFileDialog::getE&xistingDirectory()"));

        openFileNameLabel = new QLabel;
        openFileNameLabel->setFrameStyle(frameStyle);
        QPushButton *openFileNameButton =
                new QPushButton(tr("QFileDialog::get&OpenFileName()"));

        openFileNamesLabel = new QLabel;
        openFileNamesLabel->setFrameStyle(frameStyle);
        QPushButton *openFileNamesButton =
                new QPushButton(tr("QFileDialog::&getOpenFileNames()"));

        saveFileNameLabel = new QLabel;
        saveFileNameLabel->setFrameStyle(frameStyle);
        QPushButton *saveFileNameButton =
                new QPushButton(tr("QFileDialog::get&SaveFileName()"));

        criticalLabel = new QLabel;
        criticalLabel->setFrameStyle(frameStyle);
        QPushButton *criticalButton =
                new QPushButton(tr("QMessageBox::critica&l()"));

        informationLabel = new QLabel;
        informationLabel->setFrameStyle(frameStyle);
        QPushButton *informationButton =
                new QPushButton(tr("QMessageBox::i&nformation()"));

        questionLabel = new QLabel;
        questionLabel->setFrameStyle(frameStyle);
        QPushButton *questionButton =
                new QPushButton(tr("QMessageBox::&question()"));

        warningLabel = new QLabel;
        warningLabel->setFrameStyle(frameStyle);
        QPushButton *warningButton = new QPushButton(tr("QMessageBox::&warning()"));

        errorLabel = new QLabel;
        errorLabel->setFrameStyle(frameStyle);
        QPushButton *errorButton =
                new QPushButton(tr("QErrorMessage::showM&essage()"));

        connect(integerButton, SIGNAL(clicked()), this, SLOT(setInteger()));
        connect(doubleButton, SIGNAL(clicked()), this, SLOT(setDouble()));
        connect(itemButton, SIGNAL(clicked()), this, SLOT(setItem()));
        connect(textButton, SIGNAL(clicked()), this, SLOT(setText()));
        connect(multiLineTextButton, SIGNAL(clicked()), this, SLOT(setMultiLineText()));
        connect(colorButton, SIGNAL(clicked()), this, SLOT(setColor()));
        connect(fontButton, SIGNAL(clicked()), this, SLOT(setFont()));
        connect(directoryButton, SIGNAL(clicked()),
                this, SLOT(setExistingDirectory()));
        connect(openFileNameButton, SIGNAL(clicked()),
                this, SLOT(setOpenFileName()));
        connect(openFileNamesButton, SIGNAL(clicked()),
                this, SLOT(setOpenFileNames()));
        connect(saveFileNameButton, SIGNAL(clicked()),
                this, SLOT(setSaveFileName()));
        connect(criticalButton, SIGNAL(clicked()), this, SLOT(criticalMessage()));
        connect(informationButton, SIGNAL(clicked()),
                this, SLOT(informationMessage()));
        connect(questionButton, SIGNAL(clicked()), this, SLOT(questionMessage()));
        connect(warningButton, SIGNAL(clicked()), this, SLOT(warningMessage()));
        connect(errorButton, SIGNAL(clicked()), this, SLOT(errorMessage()));

        QWidget *page = new QWidget;
        QGridLayout *layout = new QGridLayout(page);
        layout->setColumnStretch(1, 1);
        layout->setColumnMinimumWidth(1, 250);
        layout->addWidget(integerButton, 0, 0);
        layout->addWidget(integerLabel, 0, 1);
        layout->addWidget(doubleButton, 1, 0);
        layout->addWidget(doubleLabel, 1, 1);
        layout->addWidget(itemButton, 2, 0);
        layout->addWidget(itemLabel, 2, 1);
        layout->addWidget(textButton, 3, 0);
        layout->addWidget(textLabel, 3, 1);
        layout->addWidget(multiLineTextButton, 4, 0);
        layout->addWidget(multiLineTextLabel, 4, 1);
        layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 5, 0);
        toolbox->addItem(page, tr("Input Dialogs"));

        const QString doNotUseNativeDialog = tr("Do not use native dialog");

        page = new QWidget;
        layout = new QGridLayout(page);
        layout->setColumnStretch(1, 1);
        layout->addWidget(colorButton, 0, 0);
        layout->addWidget(colorLabel, 0, 1);
        colorDialogOptionsWidget = new DialogOptionsWidget;
        colorDialogOptionsWidget->addCheckBox(doNotUseNativeDialog, QColorDialog::DontUseNativeDialog);
        colorDialogOptionsWidget->addCheckBox(tr("Show alpha channel") , QColorDialog::ShowAlphaChannel);
        colorDialogOptionsWidget->addCheckBox(tr("No buttons") , QColorDialog::NoButtons);
        layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 1, 0);
        layout->addWidget(colorDialogOptionsWidget, 2, 0, 1 ,2);

        toolbox->addItem(page, tr("Color Dialog"));

        page = new QWidget;
        layout = new QGridLayout(page);
        layout->setColumnStretch(1, 1);
        layout->addWidget(fontButton, 0, 0);
        layout->addWidget(fontLabel, 0, 1);
        fontDialogOptionsWidget = new DialogOptionsWidget;
        fontDialogOptionsWidget->addCheckBox(doNotUseNativeDialog, QFontDialog::DontUseNativeDialog);
        fontDialogOptionsWidget->addCheckBox(tr("No buttons") , QFontDialog::NoButtons);
        layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 1, 0);
        layout->addWidget(fontDialogOptionsWidget, 2, 0, 1 ,2);
        toolbox->addItem(page, tr("Font Dialog"));

        page = new QWidget;
        layout = new QGridLayout(page);
        layout->setColumnStretch(1, 1);
        layout->addWidget(directoryButton, 0, 0);
        layout->addWidget(directoryLabel, 0, 1);
        layout->addWidget(openFileNameButton, 1, 0);
        layout->addWidget(openFileNameLabel, 1, 1);
        layout->addWidget(openFileNamesButton, 2, 0);
        layout->addWidget(openFileNamesLabel, 2, 1);
        layout->addWidget(saveFileNameButton, 3, 0);
        layout->addWidget(saveFileNameLabel, 3, 1);
        fileDialogOptionsWidget = new DialogOptionsWidget;
        fileDialogOptionsWidget->addCheckBox(doNotUseNativeDialog, QFileDialog::DontUseNativeDialog);
        fileDialogOptionsWidget->addCheckBox(tr("Show directories only"), QFileDialog::ShowDirsOnly);
        fileDialogOptionsWidget->addCheckBox(tr("Do not resolve symlinks"), QFileDialog::DontResolveSymlinks);
        fileDialogOptionsWidget->addCheckBox(tr("Do not confirm overwrite"), QFileDialog::DontConfirmOverwrite);
        fileDialogOptionsWidget->addCheckBox(tr("Do not use sheet"), QFileDialog::DontUseSheet);
        fileDialogOptionsWidget->addCheckBox(tr("Readonly"), QFileDialog::ReadOnly);
        fileDialogOptionsWidget->addCheckBox(tr("Hide name filter details"), QFileDialog::HideNameFilterDetails);
        layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 4, 0);
        layout->addWidget(fileDialogOptionsWidget, 5, 0, 1 ,2);
        toolbox->addItem(page, tr("File Dialogs"));

        page = new QWidget;
        layout = new QGridLayout(page);
        layout->setColumnStretch(1, 1);
        layout->addWidget(criticalButton, 0, 0);
        layout->addWidget(criticalLabel, 0, 1);
        layout->addWidget(informationButton, 1, 0);
        layout->addWidget(informationLabel, 1, 1);
        layout->addWidget(questionButton, 2, 0);
        layout->addWidget(questionLabel, 2, 1);
        layout->addWidget(warningButton, 3, 0);
        layout->addWidget(warningLabel, 3, 1);
        layout->addWidget(errorButton, 4, 0);
        layout->addWidget(errorLabel, 4, 1);
        layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 5, 0);
        toolbox->addItem(page, tr("Message Boxes"));

        setWindowTitle(tr("Standard Dialogs"));
    }

    void Dialog::setInteger()
    {
        bool ok;
        int i = QInputDialog::getInt(this, tr("QInputDialog::getInteger()"),
                                     tr("Percentage:"), 25, 0, 100, 1, &ok);
        if (ok)
            integerLabel->setText(tr("%1%").arg(i));
    }

    void Dialog::setDouble()
    {
        bool ok;
        double d = QInputDialog::getDouble(this, tr("QInputDialog::getDouble()"),
                                           tr("Amount:"), 37.56, -10000, 10000, 2, &ok);
        if (ok)
            doubleLabel->setText(QString("$%1").arg(d));
    }

    void Dialog::setItem()
    {
        QStringList items;
        items << tr("Spring") << tr("Summer") << tr("Fall") << tr("Winter");

        bool ok;
        QString item = QInputDialog::getItem(this, tr("QInputDialog::getItem()"),
                                             tr("Season:"), items, 0, false, &ok);
        if (ok && !item.isEmpty())
            itemLabel->setText(item);
    }

    void Dialog::setText()
    {
        bool ok;
        QString text = QInputDialog::getText(this, tr("QInputDialog::getText()"),
                                             tr("User name:"), QLineEdit::Normal,
                                             QDir::home().dirName(), &ok);
        if (ok && !text.isEmpty())
            textLabel->setText(text);
    }

    void Dialog::setMultiLineText()
    {
        bool ok;
        QString text = QInputDialog::getMultiLineText(this, tr("QInputDialog::getMultiLineText()"),
                                                      tr("Address:"), "John Doe\nFreedom Street", &ok);
        if (ok && !text.isEmpty())
            multiLineTextLabel->setText(text);
    }

    void Dialog::setColor()
    {
        const QColorDialog::ColorDialogOptions options = QFlag(colorDialogOptionsWidget->value());
        const QColor color = QColorDialog::getColor(Qt::green, this, "Select Color", options);

        if (color.isValid()) {
            colorLabel->setText(color.name());
            colorLabel->setPalette(QPalette(color));
            colorLabel->setAutoFillBackground(true);
        }
    }

    void Dialog::setFont()
    {
        const QFontDialog::FontDialogOptions options = QFlag(fontDialogOptionsWidget->value());
        bool ok;
        QFont font = QFontDialog::getFont(&ok, QFont(fontLabel->text()), this, "Select Font", options);
        if (ok) {
            fontLabel->setText(font.key());
            fontLabel->setFont(font);
        }
    }

    void Dialog::setExistingDirectory()
    {
        QFileDialog::Options options = QFlag(fileDialogOptionsWidget->value());
        options |= QFileDialog::DontResolveSymlinks | QFileDialog::ShowDirsOnly;
        QString directory = QFileDialog::getExistingDirectory(this,
                                    tr("QFileDialog::getExistingDirectory()"),
                                    directoryLabel->text(),
                                    options);
        if (!directory.isEmpty())
            directoryLabel->setText(directory);
    }

    void Dialog::setOpenFileName()
    {
        const QFileDialog::Options options = QFlag(fileDialogOptionsWidget->value());
        QString selectedFilter;
        QString fileName = QFileDialog::getOpenFileName(this,
                                    tr("QFileDialog::getOpenFileName()"),
                                    openFileNameLabel->text(),
                                    tr("All Files (*);;Text Files (*.txt)"),
                                    &selectedFilter,
                                    options);
        if (!fileName.isEmpty())
            openFileNameLabel->setText(fileName);
    }

    void Dialog::setOpenFileNames()
    {
        const QFileDialog::Options options = QFlag(fileDialogOptionsWidget->value());
        QString selectedFilter;
        QStringList files = QFileDialog::getOpenFileNames(
                                    this, tr("QFileDialog::getOpenFileNames()"),
                                    openFilesPath,
                                    tr("All Files (*);;Text Files (*.txt)"),
                                    &selectedFilter,
                                    options);
        if (files.count()) {
            openFilesPath = files[0];
            openFileNamesLabel->setText(QString("[%1]").arg(files.join(", ")));
        }
    }

    void Dialog::setSaveFileName()
    {
        const QFileDialog::Options options = QFlag(fileDialogOptionsWidget->value());
        QString selectedFilter;
        QString fileName = QFileDialog::getSaveFileName(this,
                                    tr("QFileDialog::getSaveFileName()"),
                                    saveFileNameLabel->text(),
                                    tr("All Files (*);;Text Files (*.txt)"),
                                    &selectedFilter,
                                    options);
        if (!fileName.isEmpty())
            saveFileNameLabel->setText(fileName);
    }

    void Dialog::criticalMessage()
    {
        QMessageBox::StandardButton reply;
        reply = QMessageBox::critical(this, tr("QMessageBox::critical()"),
                                        MESSAGE,
                                        QMessageBox::Abort | QMessageBox::Retry | QMessageBox::Ignore);
        if (reply == QMessageBox::Abort)
            criticalLabel->setText(tr("Abort"));
        else if (reply == QMessageBox::Retry)
            criticalLabel->setText(tr("Retry"));
        else
            criticalLabel->setText(tr("Ignore"));
    }

    void Dialog::informationMessage()
    {
        QMessageBox::StandardButton reply;
        reply = QMessageBox::information(this, tr("QMessageBox::information()"), MESSAGE);
        if (reply == QMessageBox::Ok)
            informationLabel->setText(tr("OK"));
        else
            informationLabel->setText(tr("Escape"));
    }

    void Dialog::questionMessage()
    {
        QMessageBox::StandardButton reply;
        reply = QMessageBox::question(this, tr("QMessageBox::question()"),
                                        MESSAGE,
                                        QMessageBox::Yes | QMessageBox::No | QMessageBox::Cancel);
        if (reply == QMessageBox::Yes)
            questionLabel->setText(tr("Yes"));
        else if (reply == QMessageBox::No)
            questionLabel->setText(tr("No"));
        else
            questionLabel->setText(tr("Cancel"));
    }

    void Dialog::warningMessage()
    {
        QMessageBox msgBox(QMessageBox::Warning, tr("QMessageBox::warning()"),
                           MESSAGE, 0, this);
        msgBox.setDetailedText(MESSAGE_DETAILS);
        msgBox.addButton(tr("Save &Again"), QMessageBox::AcceptRole);
        msgBox.addButton(tr("&Continue"), QMessageBox::RejectRole);
        if (msgBox.exec() == QMessageBox::AcceptRole)
            warningLabel->setText(tr("Save Again"));
        else
            warningLabel->setText(tr("Continue"));

    }

    void Dialog::errorMessage()
    {
        errorMessageDialog->showMessage(
                tr("This dialog shows and remembers error messages. "
                   "If the checkbox is checked (as it is by default), "
                   "the shown message will be shown again, "
                   "but if the user unchecks the box the message "
                   "will not appear again if QErrorMessage::showMessage() "
                   "is called with the same message."));
        errorLabel->setText(tr("If the box is unchecked, the message "
                               "won't appear again."));
    }