src/declarative/util/qdeclarativebehavior.cpp
changeset 30 5dc02b23752f
child 33 3e2da88830cd
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/declarative/util/qdeclarativebehavior.cpp	Tue Jul 06 15:10:48 2010 +0300
@@ -0,0 +1,211 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying
+** this package.
+**
+** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "private/qdeclarativebehavior_p.h"
+
+#include "private/qdeclarativeanimation_p.h"
+#include "private/qdeclarativetransition_p.h"
+
+#include <qdeclarativecontext.h>
+#include <qdeclarativeinfo.h>
+#include <qdeclarativeproperty_p.h>
+#include <qdeclarativeguard_p.h>
+#include <qdeclarativeengine_p.h>
+
+#include <private/qobject_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QDeclarativeBehaviorPrivate : public QObjectPrivate
+{
+    Q_DECLARE_PUBLIC(QDeclarativeBehavior)
+public:
+    QDeclarativeBehaviorPrivate() : animation(0), enabled(true), finalized(false) {}
+
+    QDeclarativeProperty property;
+    QVariant currentValue;
+    QVariant targetValue;
+    QDeclarativeGuard<QDeclarativeAbstractAnimation> animation;
+    bool enabled;
+    bool finalized;
+};
+
+/*!
+    \qmlclass Behavior QDeclarativeBehavior
+    \since 4.7
+    \brief The Behavior element allows you to specify a default animation for a property change.
+
+    Behaviors provide one way to specify \l{qdeclarativeanimation.html}{animations} in QML.
+
+    In the example below, the rectangle will use a bounce easing curve over 200 millisecond for any changes to its y property:
+    \code
+    Rectangle {
+        width: 20; height: 20
+        color: "#00ff00"
+        y: 200  // initial value
+        Behavior on y {
+            NumberAnimation {
+                easing.type: Easing.OutBounce
+                easing.amplitude: 100
+                duration: 200
+            }
+        }
+    }
+    \endcode
+
+    Currently only a single Behavior may be specified for a property;
+    this Behavior can be enabled and disabled via the \l{enabled} property.
+
+    \sa QtDeclarative
+*/
+
+
+QDeclarativeBehavior::QDeclarativeBehavior(QObject *parent)
+    : QObject(*(new QDeclarativeBehaviorPrivate), parent)
+{
+}
+
+QDeclarativeBehavior::~QDeclarativeBehavior()
+{
+}
+
+/*!
+    \qmlproperty Animation Behavior::animation
+    \default
+
+    The animation to use when the behavior is triggered.
+*/
+
+QDeclarativeAbstractAnimation *QDeclarativeBehavior::animation()
+{
+    Q_D(QDeclarativeBehavior);
+    return d->animation;
+}
+
+void QDeclarativeBehavior::setAnimation(QDeclarativeAbstractAnimation *animation)
+{
+    Q_D(QDeclarativeBehavior);
+    if (d->animation) {
+        qmlInfo(this) << tr("Cannot change the animation assigned to a Behavior.");
+        return;
+    }
+
+    d->animation = animation;
+    if (d->animation) {
+        d->animation->setDefaultTarget(d->property);
+        d->animation->setDisableUserControl();
+    }
+}
+
+/*!
+    \qmlproperty bool Behavior::enabled
+    Whether the Behavior will be triggered when the property it is tracking changes.
+
+    By default a Behavior is enabled.
+*/
+
+bool QDeclarativeBehavior::enabled() const
+{
+    Q_D(const QDeclarativeBehavior);
+    return d->enabled;
+}
+
+void QDeclarativeBehavior::setEnabled(bool enabled)
+{
+    Q_D(QDeclarativeBehavior);
+    if (d->enabled == enabled)
+        return;
+    d->enabled = enabled;
+    emit enabledChanged();
+}
+
+void QDeclarativeBehavior::write(const QVariant &value)
+{
+    Q_D(QDeclarativeBehavior);
+    qmlExecuteDeferred(this);
+    if (!d->animation || !d->enabled || !d->finalized) {
+        QDeclarativePropertyPrivate::write(d->property, value, QDeclarativePropertyPrivate::BypassInterceptor | QDeclarativePropertyPrivate::DontRemoveBinding);
+        d->targetValue = value;
+        return;
+    }
+
+    if (value == d->targetValue)
+        return;
+
+    d->currentValue = d->property.read();
+    d->targetValue = value;
+
+    if (d->animation->qtAnimation()->duration() != -1)
+        d->animation->qtAnimation()->stop();
+
+    QDeclarativeStateOperation::ActionList actions;
+    QDeclarativeAction action;
+    action.property = d->property;
+    action.fromValue = d->currentValue;
+    action.toValue = value;
+    actions << action;
+
+    QList<QDeclarativeProperty> after;
+    d->animation->transition(actions, after, QDeclarativeAbstractAnimation::Forward);
+    d->animation->qtAnimation()->start();
+    if (!after.contains(d->property))
+        QDeclarativePropertyPrivate::write(d->property, value, QDeclarativePropertyPrivate::BypassInterceptor | QDeclarativePropertyPrivate::DontRemoveBinding);    
+}
+
+void QDeclarativeBehavior::setTarget(const QDeclarativeProperty &property)
+{
+    Q_D(QDeclarativeBehavior);
+    d->property = property;
+    d->currentValue = property.read();
+    if (d->animation)
+        d->animation->setDefaultTarget(property);
+
+    QDeclarativeEnginePrivate *engPriv = QDeclarativeEnginePrivate::get(qmlEngine(this));
+    engPriv->registerFinalizedParserStatusObject(this, this->metaObject()->indexOfSlot("componentFinalized()"));
+}
+
+void QDeclarativeBehavior::componentFinalized()
+{
+    Q_D(QDeclarativeBehavior);
+    d->finalized = true;
+}
+
+QT_END_NAMESPACE