// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include <QtWidgets>
#include <QCoreApplication>

void examples()
{
    QPushButton *myPushButton;

    {
        //! [21]
        qApp->setStyleSheet("QPushButton { color: white }");
        //! [21]
    }

    {
        //! [22]
        myPushButton->setStyleSheet("* { color: blue }");
        //! [22]
    }

    {
        //! [23]
        myPushButton->setStyleSheet("color: blue");
        //! [23]
    }

    {
        //! [24]
        qApp->setStyleSheet("QGroupBox { color: red; } ");
        //! [24]
    }

    {
        //! [25]
        qApp->setStyleSheet("QGroupBox, QGroupBox * { color: red; }");
        //! [25]
    }
}

//! [26]
class MyPushButton : public QPushButton {
    // ...
};

// ...
void someFunction()
{
    qApp->setStyleSheet("MyPushButton { background: yellow; }");
    //...
//! [26]
}

//! [27]
namespace ns {
    class MyPushButton : public QPushButton {
        // ...
    };
}

// ...
void someMethod()
{
    qApp->setStyleSheet("ns--MyPushButton { background: yellow; }");
    //...
//! [27]
}

class CustomWidget : public QWidget
{
    Q_OBJECT
public:
    void wrap();
    void paintEvent(QPaintEvent *event) override;
private:
    QWidget *myDialog;
    QWidget *nameEdit;
};
//! [32]
void CustomWidget::paintEvent(QPaintEvent *)
{
    QStyleOption opt;
    opt.initFrom(this);
    QPainter p(this);
    style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
}
//! [32]

void CustomWidget::wrap()
{
    {
        //! [88]
        qApp->setStyleSheet("QLineEdit { background-color: yellow }");
        //! [88]
    }

    {
        //! [89]
        myDialog->setStyleSheet("QLineEdit { background-color: yellow }");
        //! [89]
    }

    {
        //! [90]
        myDialog->setStyleSheet("QLineEdit#nameEdit { background-color: yellow }");
        //! [90]
    }

    {
        //! [91]
        nameEdit->setStyleSheet("background-color: yellow");
        //! [91]
    }

    {
        //! [92]
        nameEdit->setStyleSheet("color: blue; background-color: yellow");
        //! [92]
    }

    {
        //! [93]
        nameEdit->setStyleSheet("color: blue;"
                                "background-color: yellow;"
                                "selection-color: yellow;"
                                "selection-background-color: blue;");
        //! [93]
    }

    {
        //! [95]
        QLineEdit *nameEdit = new QLineEdit(this);
        nameEdit->setProperty("mandatoryField", true);

        QLineEdit *emailEdit = new QLineEdit(this);
        emailEdit->setProperty("mandatoryField", true);

        QSpinBox *ageSpinBox = new QSpinBox(this);
        ageSpinBox->setProperty("mandatoryField", true);
        //! [95]
    }

    {
        //! [96]
        QCoreApplication::setAttribute(Qt::AA_UseStyleSheetPropagationInWidgetStyles, true);
        //! [96]
    }
}