Add a gettext example

Add a small example along with a German translation using gettext.
Add a tutorial.

Pick-to: 6.1
Change-Id: I254a5a66521ecc2827a5811469d9d21360f99b81
Reviewed-by: Christian Tismer <tismer@stackless.com>

5 files changed, 239 insertions, 0 deletions

diff --git a/examples/widgets/gettext/gettext.pyproject b/examples/widgets/gettext/gettext.pyproject
new file mode 100644
index 000000000..f304bf8a5
--- /dev/null
+++ b/examples/widgets/gettext/gettext.pyproject
@@ -0,0 +1,4 @@
+{
+    "files": ["main.py", "locales/example.pot",
+              "locales/de_DE/LC_MESSAGES/example.pot"]
+}
diff --git a/examples/widgets/gettext/locales/de_DE/LC_MESSAGES/example.mo b/examples/widgets/gettext/locales/de_DE/LC_MESSAGES/example.mo
new file mode 100644
index 000000000..c1862497d
--- /dev/null
+++ b/examples/widgets/gettext/locales/de_DE/LC_MESSAGES/example.mo
diff --git a/examples/widgets/gettext/locales/de_DE/LC_MESSAGES/example.pot b/examples/widgets/gettext/locales/de_DE/LC_MESSAGES/example.pot
new file mode 100644
index 000000000..07b0e09c9
--- /dev/null
+++ b/examples/widgets/gettext/locales/de_DE/LC_MESSAGES/example.pot
@@ -0,0 +1,69 @@
+#############################################################################
+##
+## Copyright (C) 2021 The Qt Company Ltd.
+## Contact: http://www.qt.io/licensing/
+##
+## This file is part of the Qt for Python examples of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:BSD$
+## You may use this file under the terms of the BSD license as follows:
+##
+## "Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are
+## met:
+##   * Redistributions of source code must retain the above copyright
+##     notice, this list of conditions and the following disclaimer.
+##   * Redistributions in binary form must reproduce the above copyright
+##     notice, this list of conditions and the following disclaimer in
+##     the documentation and/or other materials provided with the
+##     distribution.
+##   * Neither the name of The Qt Company Ltd nor the names of its
+##     contributors may be used to endorse or promote products derived
+##     from this software without specific prior written permission.
+##
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: PySide6 gettext example\n"
+"POT-Creation-Date: 2021-07-05 14:16+0200\n"
+"Language: de_DE\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Plural-Forms: nplurals=2; plural=n != 1;\n"
+
+#: main.py:57
+msgid "&File"
+msgstr "&Datei"
+
+#: main.py:58
+msgid "Quit"
+msgstr "Beenden"
+
+#: main.py:59
+msgid "CTRL+Q"
+msgstr "CTRL+B"
+
+#: main.py:73
+#, python-brace-format
+msgid "{0} language selected"
+msgid_plural "{0} languages selected"
+msgstr[0] "{0} Sprache ausgewählt"
+msgstr[1] "{0} Sprachen ausgewählt"
diff --git a/examples/widgets/gettext/locales/example.pot b/examples/widgets/gettext/locales/example.pot
new file mode 100644
index 000000000..e2c16e407
--- /dev/null
+++ b/examples/widgets/gettext/locales/example.pot
@@ -0,0 +1,69 @@
+#############################################################################
+##
+## Copyright (C) 2021 The Qt Company Ltd.
+## Contact: http://www.qt.io/licensing/
+##
+## This file is part of the Qt for Python examples of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:BSD$
+## You may use this file under the terms of the BSD license as follows:
+##
+## "Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are
+## met:
+##   * Redistributions of source code must retain the above copyright
+##     notice, this list of conditions and the following disclaimer.
+##   * Redistributions in binary form must reproduce the above copyright
+##     notice, this list of conditions and the following disclaimer in
+##     the documentation and/or other materials provided with the
+##     distribution.
+##   * Neither the name of The Qt Company Ltd nor the names of its
+##     contributors may be used to endorse or promote products derived
+##     from this software without specific prior written permission.
+##
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: PySide6 gettext example\n"
+"POT-Creation-Date: 2021-07-05 14:16+0200\n"
+"Language: de_DE\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Plural-Forms: nplurals=2; plural==n != 1;\n"
+
+#: main.py:57
+msgid "&File"
+msgstr ""
+
+#: main.py:58
+msgid "Quit"
+msgstr ""
+
+#: main.py:59
+msgid "CTRL+Q"
+msgstr ""
+
+#: main.py:73
+#, python-brace-format
+msgid "{0} language selected"
+msgid_plural "{0} languages selected"
+msgstr[0] ""
+msgstr[1] ""
diff --git a/examples/widgets/gettext/main.py b/examples/widgets/gettext/main.py
new file mode 100644
index 000000000..be0579263
--- /dev/null
+++ b/examples/widgets/gettext/main.py
@@ -0,0 +1,97 @@
+#############################################################################
+##
+## Copyright (C) 2021 The Qt Company Ltd.
+## Contact: http://www.qt.io/licensing/
+##
+## This file is part of the Qt for Python examples of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:BSD$
+## You may use this file under the terms of the BSD license as follows:
+##
+## "Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are
+## met:
+##   * Redistributions of source code must retain the above copyright
+##     notice, this list of conditions and the following disclaimer.
+##   * Redistributions in binary form must reproduce the above copyright
+##     notice, this list of conditions and the following disclaimer in
+##     the documentation and/or other materials provided with the
+##     distribution.
+##   * Neither the name of The Qt Company Ltd nor the names of its
+##     contributors may be used to endorse or promote products derived
+##     from this software without specific prior written permission.
+##
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+from pathlib import Path
+import gettext
+import sys
+
+from PySide6.QtCore import QItemSelection, QLocale, Qt, Slot
+from PySide6.QtWidgets import (QAbstractItemView, QApplication, QListWidget,
+                               QMainWindow, QWidget)
+
+
+_ = None
+ngettext = None
+
+
+class Window(QMainWindow):
+    def __init__(self):
+        super().__init__()
+        file_menu = self.menuBar().addMenu(_("&File"))
+        quit_action = file_menu.addAction(_("Quit"))
+        quit_action.setShortcut(_("CTRL+Q"))
+        quit_action.triggered.connect(self.close)
+
+        self._list_widget = QListWidget()
+        self._list_widget.setSelectionMode(QAbstractItemView.MultiSelection)
+        self._list_widget.selectionModel().selectionChanged.connect(self.selection_changed)
+        self._list_widget.addItem("C++")
+        self._list_widget.addItem("Java")
+        self._list_widget.addItem("Python")
+        self.setCentralWidget(self._list_widget)
+
+    @Slot(QItemSelection, QItemSelection)
+    def selection_changed(self, selected, deselected):
+        count = len(self._list_widget.selectionModel().selectedRows())
+        message = ngettext("{0} language selected",
+                           "{0} languages selected", count).format(count)
+        self.statusBar().showMessage(message)
+
+
+if __name__ == '__main__':
+    app = QApplication(sys.argv)
+
+    src_dir = Path(__file__).resolve().parent
+    try:
+        translation = gettext.translation('example', localedir=src_dir / 'locales')
+        if translation:
+            translation.install()
+            _ = translation.gettext
+            ngettext = translation.ngettext
+    except FileNotFoundError:
+        pass
+    if not _:
+        _ = gettext.gettext
+        ngettext = gettext.ngettext
+        print('No translation found')
+
+    window = Window()
+    window.show()
+    sys.exit(app.exec())