Pluginize the platform styles

This enforces decoupling and in the case of QMacStyle, isolates
QtWidgets and therefore end user applications, from Carbon/HITheme.

Windows and Fusion are platform independent, so they remain built-in
(but mostly because the Windows style is tightly coupled to other styles
like QStylesheetStyle).

Task-number: QTBUG-59428
Change-Id: Id6519fe0c5269c1bce5b5921f9db06257032a1c9
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@qt.io>

src/plugins/plugins.pro

@@ -8,6 +8,7 @@ qtHaveModule(gui) {
     qtConfig(imageformatplugin): SUBDIRS *= imageformats
     !android:qtConfig(library): SUBDIRS *= generic
 }
+qtHaveModule(widgets): SUBDIRS += styles
 
 !winrt:!wince:qtHaveModule(printsupport): \
     SUBDIRS += printsupport

src/plugins/styles/android/android.pro

@@ -0,0 +1,16 @@
+TARGET = qandroidstyle
+
+QT += widgets-private
+
+SOURCES += \
+    main.cpp \
+    qandroidstyle.cpp
+
+HEADERS += \
+    qandroidstyle_p.h
+
+DISTFILES += androidstyle.json
+
+PLUGIN_TYPE = styles
+PLUGIN_CLASS_NAME = QAndroidStylePlugin
+load(qt_plugin)

src/plugins/styles/android/androidstyle.json

@@ -0,0 +1,3 @@
+{
+    "Keys": [ "android" ]
+}

src/plugins/styles/android/main.cpp

@@ -0,0 +1,64 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtWidgets/qstyleplugin.h>
+#include "qandroidstyle_p.h"
+
+QT_BEGIN_NAMESPACE
+
+class QAndroidStylePlugin : public QStylePlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QStyleFactoryInterface" FILE "androidstyle.json")
+public:
+    QStyle *create(const QString &key);
+};
+
+QStyle *QAndroidStylePlugin::create(const QString &key)
+{
+    if (key.compare(QLatin1String("android"), Qt::CaseInsensitive) == 0)
+        return new QAndroidStyle();
+
+    return 0;
+}
+
+QT_END_NAMESPACE
+
+#include "main.moc"
+

src/widgets/styles/qandroidstyle.cpp → src/plugins/styles/android/qandroidstyle.cpp

@@ -39,8 +39,6 @@
 
 #include "qandroidstyle_p.h"
 
-#if QT_CONFIG(style_android) || defined(QT_PLUGIN)
-
 #include <QFile>
 #include <QFont>
 #include <QApplication>
@@ -1805,5 +1803,3 @@ QRect QAndroidStyle::AndroidSpinnerControl::subControlRect(const QStyleOptionCom
 }
 
 QT_END_NAMESPACE
-
-#endif // QT_CONFIG(style_android) || defined(QT_PLUGIN)

src/widgets/styles/qandroidstyle_p.h → src/plugins/styles/android/qandroidstyle_p.h

@@ -52,16 +52,14 @@
 //
 
 #include <QtWidgets/private/qtwidgetsglobal_p.h>
+#include <QtWidgets/private/qfusionstyle_p.h>
 #include <QtCore/QList>
 #include <QtCore/QMargins>
 #include <QtCore/QHash>
 #include <QtCore/QVariantMap>
-#include "qfusionstyle_p.h"
 
 QT_BEGIN_NAMESPACE
 
-#if QT_CONFIG(style_android)
-
 class Q_WIDGETS_EXPORT QAndroidStyle : public QFusionStyle
 {
     Q_OBJECT
@@ -388,8 +386,6 @@ class Q_WIDGETS_EXPORT QAndroidStyle : public QFusionStyle
     AndroidCompoundButtonControl *checkBoxControl;
 };
 
-#endif // style_android
-
 QT_END_NAMESPACE
 
 #endif // QANDROIDSTYLE_P_H

src/plugins/styles/mac/mac.pro

@@ -0,0 +1,19 @@
+TARGET = qmacstyle
+
+QT += widgets-private
+
+SOURCES += \
+    main.mm \
+    qmacstyle_mac.mm
+
+HEADERS += \
+    qmacstyle_mac_p.h \
+    qmacstyle_mac_p_p.h
+
+LIBS_PRIVATE += -framework AppKit -framework Carbon
+
+DISTFILES += macstyle.json
+
+PLUGIN_TYPE = styles
+PLUGIN_CLASS_NAME = QMacStylePlugin
+load(qt_plugin)

src/plugins/styles/mac/macstyle.json

@@ -0,0 +1,3 @@
+{
+    "Keys": [ "macintosh" ]
+}

src/plugins/styles/mac/main.mm

@@ -0,0 +1,65 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtWidgets/qstyleplugin.h>
+#include "qmacstyle_mac_p.h"
+
+QT_BEGIN_NAMESPACE
+
+class QMacStylePlugin : public QStylePlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QStyleFactoryInterface" FILE "macstyle.json")
+public:
+    QStyle *create(const QString &key);
+};
+
+QStyle *QMacStylePlugin::create(const QString &key)
+{
+    QMacAutoReleasePool pool;
+    if (key.compare(QLatin1String("macintosh"), Qt::CaseInsensitive) == 0)
+        return new QMacStyle();
+
+    return 0;
+}
+
+QT_END_NAMESPACE
+
+#include "main.moc"
+

src/widgets/styles/qmacstyle_mac_p.h → src/plugins/styles/mac/qmacstyle_mac_p.h

@@ -56,9 +56,6 @@
 
 QT_BEGIN_NAMESPACE
 
-
-#if QT_CONFIG(style_mac)
-
 class QPalette;
 
 class QPushButton;
@@ -126,8 +123,6 @@ class QMacStyle : public QCommonStyle
 #endif
 };
 
-#endif
-
 QT_END_NAMESPACE
 
 #endif // QMACSTYLE_MAC_P_H

src/widgets/styles/qmacstyle_mac_p_p.h → src/plugins/styles/mac/qmacstyle_mac_p_p.h

@@ -45,8 +45,8 @@
 #undef check
 
 #include <QtWidgets/private/qtwidgetsglobal_p.h>
+#include <QtWidgets/private/qcommonstyle_p.h>
 #include "qmacstyle_mac_p.h"
-#include "qcommonstyle_p.h"
 #include <private/qapplication_p.h>
 #include <private/qcombobox_p.h>
 #include <private/qpainter_p.h>

src/plugins/styles/styles.pro

@@ -0,0 +1,8 @@
+TEMPLATE = subdirs
+QT_FOR_CONFIG += widgets-private
+
+qtConfig(style-android): SUBDIRS += android
+
+qtConfig(style-mac): SUBDIRS += mac
+
+qtConfig(style-windowsvista): SUBDIRS += windowsvista

src/plugins/styles/windowsvista/main.cpp

@@ -0,0 +1,64 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtWidgets/private/qtwidgetsglobal_p.h>
+#include <QtWidgets/qstyleplugin.h>
+#include "qwindowsvistastyle_p.h"
+
+QT_BEGIN_NAMESPACE
+
+class QWindowsVistaStylePlugin : public QStylePlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QStyleFactoryInterface" FILE "windowsvistastyle.json")
+public:
+    QStyle *create(const QString &key);
+};
+
+QStyle *QWindowsVistaStylePlugin::create(const QString &key)
+{
+    if (key.compare(QLatin1String("windowsvista"), Qt::CaseInsensitive) == 0)
+        return new QWindowsVistaStyle();
+
+    return 0;
+}
+
+QT_END_NAMESPACE
+
+#include "main.moc"

src/widgets/styles/qwindowsvistastyle.cpp → src/plugins/styles/windowsvista/qwindowsvistastyle.cpp

@@ -47,8 +47,6 @@
 #include <private/qapplication_p.h>
 #include <qpa/qplatformnativeinterface.h>
 
-#if QT_CONFIG(style_windowsvista) || defined(QT_PLUGIN)
-
 QT_BEGIN_NAMESPACE
 
 static const int windowsItemFrame        =  2; // menu item frame width
@@ -2487,5 +2485,3 @@ QIcon QWindowsVistaStyle::standardIcon(StandardPixmap standardIcon,
 }
 
 QT_END_NAMESPACE
-
-#endif //QT_NO_WINDOWSVISTA

src/widgets/styles/qwindowsvistastyle_p.h → src/plugins/styles/windowsvista/qwindowsvistastyle_p.h

@@ -52,13 +52,10 @@
 //
 
 #include <QtWidgets/private/qtwidgetsglobal_p.h>
-#include <private/qwindowsxpstyle_p.h>
+#include "qwindowsxpstyle_p.h"
 
 QT_BEGIN_NAMESPACE
 
-
-#if QT_CONFIG(style_windowsvista)
-
 class QWindowsVistaStylePrivate;
 class QWindowsVistaStyle : public QWindowsXPStyle
 {
@@ -103,7 +100,6 @@ class QWindowsVistaStyle : public QWindowsXPStyle
     Q_DECLARE_PRIVATE(QWindowsVistaStyle)
     friend class QStyleFactory;
 };
-#endif // style_windowsvista
 
 QT_END_NAMESPACE
 

src/widgets/styles/qwindowsvistastyle_p_p.h → src/plugins/styles/windowsvista/qwindowsvistastyle_p_p.h

@@ -53,9 +53,7 @@
 
 #include <QtWidgets/private/qtwidgetsglobal_p.h>
 #include "qwindowsvistastyle_p.h"
-
-#if QT_CONFIG(style_windowsvista)
-#include <private/qwindowsxpstyle_p_p.h>
+#include "qwindowsxpstyle_p_p.h"
 #include <private/qstyleanimation_p.h>
 #include <private/qpaintengine_raster_p.h>
 #include <qpaintengine.h>
@@ -179,6 +177,4 @@ class QWindowsVistaStylePrivate :  public QWindowsXPStylePrivate
 
 QT_END_NAMESPACE
 
-#endif // style_windowsvista
-
 #endif // QWINDOWSVISTASTYLE_P_P_H

src/widgets/styles/qwindowsxpstyle.cpp → src/plugins/styles/windowsvista/qwindowsxpstyle.cpp

@@ -39,8 +39,6 @@
 #include "qwindowsxpstyle_p.h"
 #include "qwindowsxpstyle_p_p.h"
 
-#if QT_CONFIG(style_windowsvista) || defined(QT_PLUGIN)
-
 #include <private/qobject_p.h>
 #include <private/qpaintengine_raster_p.h>
 #include <private/qapplication_p.h>
@@ -4223,5 +4221,3 @@ void QWindowsXPStylePrivate::showProperties(XPThemeData &themeData)
 
 
 QT_END_NAMESPACE
-
-#endif //QT_NO_WINDOWSXP