Resurrect wiggly example as a manual test

In addition to being an iconic part of Qt's history, wiggly is also
widely used for verifying on embedded hardware.

Change-Id: Ica86626d98ade2570eebe787860293380c21f96a
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

tests/manual/examples/widgets/wiggly/CMakeLists.txt

@@ -0,0 +1,38 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+cmake_minimum_required(VERSION 3.16)
+project(wiggly LANGUAGES CXX)
+
+if(NOT DEFINED INSTALL_EXAMPLESDIR)
+    set(INSTALL_EXAMPLESDIR "examples")
+endif()
+
+set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/widgets/widgets/wiggly")
+
+find_package(Qt6 REQUIRED COMPONENTS Core Gui Widgets)
+
+qt_standard_project_setup()
+
+qt_add_executable(wiggly
+    dialog.cpp dialog.h
+    main.cpp
+    wigglywidget.cpp wigglywidget.h
+)
+
+set_target_properties(wiggly PROPERTIES
+    WIN32_EXECUTABLE TRUE
+    MACOSX_BUNDLE TRUE
+)
+
+target_link_libraries(wiggly PRIVATE
+    Qt6::Core
+    Qt6::Gui
+    Qt6::Widgets
+)
+
+install(TARGETS wiggly
+    RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
+    BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
+    LIBRARY DESTINATION "${INSTALL_EXAMPLEDIR}"
+)

tests/manual/examples/widgets/wiggly/dialog.cpp

@@ -0,0 +1,27 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "dialog.h"
+#include "wigglywidget.h"
+
+#include <QLineEdit>
+#include <QVBoxLayout>
+
+//! [0]
+Dialog::Dialog(QWidget *parent)
+    : QDialog(parent)
+{
+    WigglyWidget *wigglyWidget = new WigglyWidget;
+    QLineEdit *lineEdit = new QLineEdit;
+
+    QVBoxLayout *layout = new QVBoxLayout(this);
+    layout->addWidget(wigglyWidget);
+    layout->addWidget(lineEdit);
+
+    connect(lineEdit, &QLineEdit::textChanged, wigglyWidget, &WigglyWidget::setText);
+    lineEdit->setText(u8"🖖 " + tr("Hello world!"));
+
+    setWindowTitle(tr("Wiggly"));
+    resize(360, 145);
+}
+//! [0]

tests/manual/examples/widgets/wiggly/dialog.h

@@ -0,0 +1,19 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef DIALOG_H
+#define DIALOG_H
+
+#include <QDialog>
+
+//! [0]
+class Dialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit Dialog(QWidget *parent = nullptr);
+};
+//! [0]
+
+#endif

tests/manual/examples/widgets/wiggly/main.cpp

@@ -0,0 +1,16 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "dialog.h"
+
+#include <QApplication>
+
+int main(int argc, char *argv[])
+{
+    QApplication app(argc, argv);
+
+    Dialog dialog;
+    dialog.show();
+
+    return app.exec();
+}

tests/manual/examples/widgets/wiggly/wiggly.pro

@@ -0,0 +1,11 @@
+QT += widgets
+
+HEADERS       = wigglywidget.h \
+                dialog.h
+SOURCES       = wigglywidget.cpp \
+                dialog.cpp \
+                main.cpp
+
+# install
+target.path = $$[QT_INSTALL_EXAMPLES]/widgets/widgets/wiggly
+INSTALLS += target

tests/manual/examples/widgets/wiggly/wigglywidget.cpp

@@ -0,0 +1,65 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "wigglywidget.h"
+
+#include <QFontMetrics>
+#include <QPainter>
+#include <QTimerEvent>
+
+//! [0]
+WigglyWidget::WigglyWidget(QWidget *parent)
+    : QWidget(parent), step(0)
+{
+    setBackgroundRole(QPalette::Midlight);
+    setAutoFillBackground(true);
+
+    QFont newFont = font();
+    newFont.setPointSize(newFont.pointSize() + 20);
+    setFont(newFont);
+
+    timer.start(60, this);
+}
+//! [0]
+
+//! [1]
+void WigglyWidget::paintEvent(QPaintEvent * /* event */)
+//! [1] //! [2]
+{
+    static constexpr int sineTable[16] = {
+        0, 38, 71, 92, 100, 92, 71, 38, 0, -38, -71, -92, -100, -92, -71, -38
+    };
+
+    QFontMetrics metrics(font());
+    int x = (width() - metrics.horizontalAdvance(text)) / 2;
+    int y = (height() + metrics.ascent() - metrics.descent()) / 2;
+    QColor color;
+//! [2]
+
+//! [3]
+    QPainter painter(this);
+//! [3] //! [4]
+    int offset = 0;
+    for (char32_t codePoint : text.toUcs4()) {
+        int index = (step + offset++) % 16;
+        color.setHsv((15 - index) * 16, 255, 191);
+        painter.setPen(color);
+        QString symbol = QString::fromUcs4(&codePoint, 1);
+        painter.drawText(x, y - ((sineTable[index] * metrics.height()) / 400), symbol);
+        x += metrics.horizontalAdvance(symbol);
+    }
+}
+//! [4]
+
+//! [5]
+void WigglyWidget::timerEvent(QTimerEvent *event)
+//! [5] //! [6]
+{
+    if (event->timerId() == timer.timerId()) {
+        ++step;
+        update();
+    } else {
+        QWidget::timerEvent(event);
+    }
+//! [6]
+}

tests/manual/examples/widgets/wiggly/wigglywidget.h

@@ -0,0 +1,32 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef WIGGLYWIDGET_H
+#define WIGGLYWIDGET_H
+
+#include <QBasicTimer>
+#include <QWidget>
+
+//! [0]
+class WigglyWidget : public QWidget
+{
+    Q_OBJECT
+
+public:
+    WigglyWidget(QWidget *parent = nullptr);
+
+public slots:
+    void setText(const QString &newText) { text = newText; }
+
+protected:
+    void paintEvent(QPaintEvent *event) override;
+    void timerEvent(QTimerEvent *event) override;
+
+private:
+    QBasicTimer timer;
+    QString text;
+    int step;
+};
+//! [0]
+
+#endif