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Diffstat (limited to 'src/declarative/util/qmlpropertymap.cpp')
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diff --git a/src/declarative/util/qmlpropertymap.cpp b/src/declarative/util/qmlpropertymap.cpp new file mode 100644 index 0000000..a587af3 --- /dev/null +++ b/src/declarative/util/qmlpropertymap.cpp @@ -0,0 +1,273 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the QtDeclarative module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** 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, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, 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. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qmlpropertymap.h" +#include <qmlopenmetaobject.h> +#include <QDebug> + +QT_BEGIN_NAMESPACE + +//QmlPropertyMapMetaObject lets us listen for changes coming from QML +//so we can emit the changed signal. +class QmlPropertyMapMetaObject : public QmlOpenMetaObject +{ +public: + QmlPropertyMapMetaObject(QmlPropertyMap *obj, QmlPropertyMapPrivate *objPriv); + +protected: + virtual void propertyWrite(int index); + +private: + QmlPropertyMap *map; + QmlPropertyMapPrivate *priv; +}; + +class QmlPropertyMapPrivate : public QObjectPrivate +{ + Q_DECLARE_PUBLIC(QmlPropertyMap) +public: + QmlPropertyMapMetaObject *mo; + QStringList keys; + void emitChanged(const QString &key); +}; + +void QmlPropertyMapPrivate::emitChanged(const QString &key) +{ + Q_Q(QmlPropertyMap); + emit q->valueChanged(key); +} + +QmlPropertyMapMetaObject::QmlPropertyMapMetaObject(QmlPropertyMap *obj, QmlPropertyMapPrivate *objPriv) : QmlOpenMetaObject(obj) +{ + map = obj; + priv = objPriv; +} + +void QmlPropertyMapMetaObject::propertyWrite(int index) +{ + priv->emitChanged(QString::fromUtf8(name(index))); +} + +/*! + \class QmlPropertyMap + \brief The QmlPropertyMap class allows you to set key-value pairs that can be used in bindings. + + QmlPropertyMap provides a convenient way to expose domain data to the UI layer. + The following example shows how you might declare data in C++ and then + access it in QML. + + Setup in C++: + \code + //create our data + QmlPropertyMap ownerData; + ownerData.insert("name", QVariant(QString("John Smith"))); + ownerData.insert("phone", QVariant(QString("555-5555"))); + + //expose it to the UI layer + QmlContext *ctxt = view->bindContext(); + ctxt->setProperty("owner", &data); + \endcode + + Then, in QML: + \code + Text { text: owner.name } + Text { text: owner.phone } + \endcode + + The binding is dynamic - whenever a key's value is updated, anything bound to that + key will be updated as well. + + To detect value changes made in the UI layer you can connect to the valueChanged() signal. + However, note that valueChanged() is \b NOT emitted when changes are made by calling insert() + or clear() - it is only emitted when a value is updated from QML. + + \note It is not possible to remove keys from the map; once a key has been added, you can only + modify or clear its associated value. +*/ + +/*! + Constructs a bindable map with parent object \a parent. +*/ +QmlPropertyMap::QmlPropertyMap(QObject *parent) +: QObject(*(new QmlPropertyMapPrivate), parent) +{ + Q_D(QmlPropertyMap); + d->mo = new QmlPropertyMapMetaObject(this, d); +} + +/*! + Destroys the bindable map. +*/ +QmlPropertyMap::~QmlPropertyMap() +{ +} + +/*! + Clears the value (if any) associated with \a key. +*/ +void QmlPropertyMap::clear(const QString &key) +{ + Q_D(QmlPropertyMap); + d->mo->setValue(key.toUtf8(), QVariant()); +} + +/*! + Returns the value associated with \a key. + + If no value has been set for this key (or if the value has been cleared), + an invalid QVariant is returned. +*/ +QVariant QmlPropertyMap::value(const QString &key) const +{ + Q_D(const QmlPropertyMap); + return d->mo->value(key.toUtf8()); +} + +/*! + Sets the value associated with \a key to \a value. + + If the key doesn't exist, it is automatically created. +*/ +void QmlPropertyMap::insert(const QString &key, const QVariant &value) +{ + Q_D(QmlPropertyMap); + if (!d->keys.contains(key)) + d->keys.append(key); + d->mo->setValue(key.toUtf8(), value); +} + +/*! + Returns the list of keys. + + Keys that have been cleared will still appear in this list, even though their + associated values are invalid QVariants. +*/ +QStringList QmlPropertyMap::keys() const +{ + Q_D(const QmlPropertyMap); + return d->keys; +} + +/*! + \overload + + Same as size(). +*/ +int QmlPropertyMap::count() const +{ + Q_D(const QmlPropertyMap); + return d->keys.count(); +} + +/*! + Returns the number of keys in the map. + + \sa isEmpty(), count() +*/ +int QmlPropertyMap::size() const +{ + Q_D(const QmlPropertyMap); + return d->keys.size(); +} + +/*! + Returns true if the map contains no keys; otherwise returns + false. + + \sa size() +*/ +bool QmlPropertyMap::isEmpty() const +{ + Q_D(const QmlPropertyMap); + return d->keys.isEmpty(); +} + +/*! + Returns true if the map contains \a key. + + \sa size() +*/ +bool QmlPropertyMap::contains(const QString &key) const +{ + Q_D(const QmlPropertyMap); + return d->keys.contains(key); +} + +/*! + Returns the value associated with the key \a key as a modifiable + reference. + + If the map contains no item with key \a key, the function inserts + an invalid QVariant into the map with key \a key, and + returns a reference to it. + + \sa insert(), value() +*/ +QVariant &QmlPropertyMap::operator[](const QString &key) +{ + //### optimize + Q_D(QmlPropertyMap); + QByteArray utf8key = key.toUtf8(); + if (!d->keys.contains(key)) { + d->keys.append(key); + d->mo->setValue(utf8key, QVariant()); //force creation -- needed below + } + + return (*(d->mo))[utf8key]; +} + +/*! + \overload + + Same as value(). +*/ +const QVariant QmlPropertyMap::operator[](const QString &key) const +{ + return value(key); +} + +/*! + \fn void QmlPropertyMap::valueChanged(const QString &key) + This signal is emitted whenever one of the values in the map is changed. \a key + is the key corresponding to the value that was changed. +*/ + +QT_END_NAMESPACE |