Apply file selectors to QQmlApplicationEngine apps

You can also manually apply them to a QQmlEngine using
setUrlInterceptor(new QQmlFileSelector(parent)), or using
your own QQmlAbstractUrlInterceptor subclass.

Change-Id: I0c0ff8b080c138686b3c03e0bc3b9f25bcd11a85
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

6 files changed, 293 insertions, 5 deletions

diff --git a/src/qml/qml/qml.pri b/src/qml/qml/qml.pri
index 8dfe0f1d3b..29c007ad07 100644
--- a/src/qml/qml/qml.pri
+++ b/src/qml/qml/qml.pri
@@ -54,7 +54,8 @@ SOURCES += \
     $$PWD/qqmllistwrapper.cpp \
     $$PWD/qqmlcontextwrapper.cpp \
     $$PWD/qqmlvaluetypewrapper.cpp \
-    $$PWD/qqmltypewrapper.cpp
+    $$PWD/qqmltypewrapper.cpp \
+    $$PWD/qqmlfileselector.cpp
 
 HEADERS += \
     $$PWD/qqmlglobal_p.h \
@@ -130,7 +131,9 @@ HEADERS += \
     $$PWD/qqmllistwrapper_p.h \
     $$PWD/qqmlcontextwrapper_p.h \
     $$PWD/qqmlvaluetypewrapper_p.h \
-    $$PWD/qqmltypewrapper_p.h
+    $$PWD/qqmltypewrapper_p.h \
+    $$PWD/qqmlfileselector_p.h \
+    $$PWD/qqmlfileselector.h
 
 include(ftw/ftw.pri)
 include(v8/v8.pri)
diff --git a/src/qml/qml/qqmlapplicationengine.cpp b/src/qml/qml/qqmlapplicationengine.cpp
index 85aeaf5786..3f13f8a140 100644
--- a/src/qml/qml/qqmlapplicationengine.cpp
+++ b/src/qml/qml/qqmlapplicationengine.cpp
@@ -44,6 +44,7 @@
 #include <QQmlComponent>
 #include "qqmlapplicationengine.h"
 #include "qqmlapplicationengine_p.h"
+#include "qqmlfileselector.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -76,6 +77,7 @@ void QQmlApplicationEnginePrivate::init()
         QCoreApplication::installTranslator(qtTranslator);
     translators << qtTranslator;
 #endif
+    q->setUrlInterceptor(new QQmlFileSelector(q));
     QCoreApplication::instance()->setProperty("__qml_using_qqmlapplicationengine", QVariant(true));
 }
 
@@ -172,13 +174,12 @@ void QQmlApplicationEnginePrivate::_q_finishLoad(QObject *o)
   \li Connecting Qt.quit() to QCoreApplication::quit()
   \li Automatically loads translation files from an i18n directory adjacent to the main QML file.
   \li Automatically sets an incubuation controller if the scene contains a QQuickWindow.
+  \li Automatically sets a \c QQmlFileSelector as the url interceptor, applying file selectors to all
+  QML files and assets.
   \endlist
 
   The engine behavior can be further tweaked by using the inherited methods from QQmlEngine.
 
-  \note In the future QQmlApplicationEngine may automatically apply file selectors.
-  To ensure forwards compatibility, do not use folder names containing a '+' character in your QML file
-  structure.
 */
 
 /*!
diff --git a/src/qml/qml/qqmlapplicationengine_p.h b/src/qml/qml/qqmlapplicationengine_p.h
index cc38c62c02..75d7cf768f 100644
--- a/src/qml/qml/qqmlapplicationengine_p.h
+++ b/src/qml/qml/qqmlapplicationengine_p.h
@@ -63,6 +63,7 @@
 QT_BEGIN_NAMESPACE
 
 class QTranslator;
+class QFileSelector;
 class Q_QML_PRIVATE_EXPORT QQmlApplicationEnginePrivate : public QQmlEnginePrivate
 {
     Q_DECLARE_PUBLIC(QQmlApplicationEngine)
diff --git a/src/qml/qml/qqmlfileselector.cpp b/src/qml/qml/qqmlfileselector.cpp
new file mode 100644
index 0000000000..5810e269eb
--- /dev/null
+++ b/src/qml/qml/qqmlfileselector.cpp
@@ -0,0 +1,138 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 BlackBerry Limited. All rights reserved.
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQml module 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtCore/QFileSelector>
+#include "qqmlfileselector.h"
+#include "qqmlfileselector_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+   \class QQmlFileSelector
+   \since 5.2
+   \inmodule QtQml
+   \brief A convenience class for applying a QFileSelector to QML file loading
+
+  QQmlFileSelector is a QQmlAbstractUrlInterceptor which will automatically apply a QFileSelector to
+  qml file and asset paths.
+
+  It is used as follows:
+
+  \code
+  QQmlEngine engine;
+  QQmlFileSelector selector;
+  engine.setUrlInterceptor(&selector);
+  \endcode
+
+  Then you can swap out files like so:
+  \code
+  main.qml
+  Component.qml
+  asset.png
+  +unix/Component.qml
+  +mac/asset.png
+  \endcode
+
+  In this example, main.qml will normally use Component.qml for the Component type. However on a
+  unix platform, the unix selector will be present and the +unix/Component.qml version will be
+  used instead. Note that this acts like swapping out Component.qml with +unix/Component.qml, so
+  when using Component.qml you should not need to alter any paths based on which version was
+  selected.
+
+  For example, to pass the "asset.png" file path around you would refer to it just as "asset.png" in
+  all of main.qml, Component.qml, and +linux/Component.qml. It will be replaced with +mac/asset.png
+  on Mac platforms in all cases.
+
+  For a list of available selectors, see \c QFileSelector.
+
+  Your platform may also provide additional selectors for you to use. As specified by QFileSelector,
+  directories used for selection must start with a '+' character, so you will not accidentally
+  trigger this feature unless you have directories with such names inside your project.
+ */
+
+/*!
+  Creates a new QQmlFileSelector, which includes its own QFileSelector.
+*/
+
+QQmlFileSelector::QQmlFileSelector(QObject* parent)
+    : QObject(*(new QQmlFileSelectorPrivate), parent)
+{
+}
+
+QQmlFileSelectorPrivate::QQmlFileSelectorPrivate()
+{
+    Q_Q(QQmlFileSelector);
+    ownSelector = true;
+    selector = new QFileSelector(q);
+}
+
+/*!
+  Sets a different QFileSelector instance for use by the QQmlFileSelector. QQmlFileSelector does not
+  take ownership of the new QFileSelector. To reset QQmlFileSelector to use its internal
+  QFileSelector instance, call setSelector(0).
+*/
+
+void QQmlFileSelector::setSelector(QFileSelector *selector)
+{
+    Q_D(QQmlFileSelector);
+    if (selector) {
+        if (d->ownSelector) {
+            delete d->selector;
+            d->ownSelector = false;
+        }
+        d->selector = selector;
+    } else {
+        if (!d->ownSelector) {
+            d->ownSelector = true;
+            d->selector = new QFileSelector(this);
+        } // Do nothing if already using internal selector
+    }
+}
+
+QUrl QQmlFileSelector::intercept(const QUrl &path, DataType type)
+{
+    Q_D(QQmlFileSelector);
+    if ( type ==  QQmlAbstractUrlInterceptor::QmldirFile ) //Don't intercept qmldir files, to prevent double interception
+        return path;
+    return d->selector->select(path);
+}
+
+QT_END_NAMESPACE
diff --git a/src/qml/qml/qqmlfileselector.h b/src/qml/qml/qqmlfileselector.h
new file mode 100644
index 0000000000..0152ce292a
--- /dev/null
+++ b/src/qml/qml/qqmlfileselector.h
@@ -0,0 +1,71 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 BlackBerry Limited. All rights reserved.
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQml module 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLFILESELECTOR_H
+#define QQMLFILESELECTOR_H
+
+#include <QtCore/QObject>
+#include <QtCore/QUrl>
+#include <QtQml/QQmlAbstractUrlInterceptor>
+#include <qtqmlglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+class QFileSelector;
+class QQmlFileSelectorPrivate;
+class Q_QML_EXPORT QQmlFileSelector : public QObject, public QQmlAbstractUrlInterceptor
+{
+    Q_OBJECT
+    Q_DECLARE_PRIVATE(QQmlFileSelector)
+public:
+    QQmlFileSelector(QObject* parent=0);
+    void setSelector(QFileSelector *selector);
+
+protected:
+    virtual QUrl intercept(const QUrl &path, DataType type);
+
+private:
+    Q_DISABLE_COPY(QQmlFileSelector)
+};
+
+QT_END_NAMESPACE
+
+#endif
diff --git a/src/qml/qml/qqmlfileselector_p.h b/src/qml/qml/qqmlfileselector_p.h
new file mode 100644
index 0000000000..60d6072c8c
--- /dev/null
+++ b/src/qml/qml/qqmlfileselector_p.h
@@ -0,0 +1,74 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 BlackBerry Limited. All rights reserved.
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQml module 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLFILESELECTOR_P_H
+#define QQMLFILESELECTOR_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include "qqmlfileselector.h"
+#include <private/qobject_p.h>
+#include <private/qtqmlglobal_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QFileSelector;
+class Q_QML_PRIVATE_EXPORT QQmlFileSelectorPrivate : public QObjectPrivate
+{
+    Q_DECLARE_PUBLIC(QQmlFileSelector)
+public:
+    QQmlFileSelectorPrivate();
+    QFileSelector* selector;
+    bool ownSelector;
+};
+
+QT_END_NAMESPACE
+
+#endif