src/qtquick1/util/qdeclarativebehavior.cpp

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  41
  42 #include "QtQuick1/private/qdeclarativebehavior_p.h"
  43
  44 #include "QtQuick1/private/qdeclarativeanimation_p.h"
  45 #include "QtQuick1/private/qdeclarativetransition_p.h"
  46
  47 #include <QtDeclarative/qdeclarativecontext.h>
  48 #include <QtDeclarative/qdeclarativeinfo.h>
  49 #include <QtDeclarative/private/qdeclarativeproperty_p.h>
  50 #include <QtDeclarative/private/qdeclarativeguard_p.h>
  51 #include <QtDeclarative/private/qdeclarativeengine_p.h>
  52
  53 #include <private/qobject_p.h>
  54
  55 QT_BEGIN_NAMESPACE
  56
  57
  58
  59 class QDeclarative1BehaviorPrivate : public QObjectPrivate
  60 {
  61     Q_DECLARE_PUBLIC(QDeclarative1Behavior)
  62 public:
  63     QDeclarative1BehaviorPrivate() : animation(0), enabled(true), finalized(false)
  64       , blockRunningChanged(false) {}
  65
  66     QDeclarativeProperty property;
  67     QVariant currentValue;
  68     QVariant targetValue;
  69     QDeclarativeGuard<QDeclarative1AbstractAnimation> animation;
  70     bool enabled;
  71     bool finalized;
  72     bool blockRunningChanged;
  73 };
  74
  75 /*!
  76     \qmlclass Behavior QDeclarative1Behavior
  77     \inqmlmodule QtQuick 1
  78     \ingroup qml-animation-transition
  79     \since QtQuick 1.0
  80     \brief The Behavior element allows you to specify a default animation for a property change.
  81
  82     A Behavior defines the default animation to be applied whenever a
  83     particular property value changes.
  84
  85     For example, the following Behavior defines a NumberAnimation to be run
  86     whenever the \l Rectangle's \c width value changes. When the MouseArea
  87     is clicked, the \c width is changed, triggering the behavior's animation:
  88
  89     \snippet doc/src/snippets/qtquick1/behavior.qml 0
  90
  91     Note that a property cannot have more than one assigned Behavior. To provide
  92     multiple animations within a Behavior, use ParallelAnimation or
  93     SequentialAnimation.
  94
  95     If a \l{QML States}{state change} has a \l Transition that matches the same property as a
  96     Behavior, the \l Transition animation overrides the Behavior for that
  97     state change. For general advice on using Behaviors to animate state changes, see
  98     \l{Using QML Behaviors with States}.
  99
 100     \sa {QML Animation and Transitions}, {declarative/animation/behaviors}{Behavior example}, QtDeclarative
 101 */
 102
 103
 104 QDeclarative1Behavior::QDeclarative1Behavior(QObject *parent)
 105     : QObject(*(new QDeclarative1BehaviorPrivate), parent)
 106 {
 107 }
 108
 109 QDeclarative1Behavior::~QDeclarative1Behavior()
 110 {
 111 }
 112
 113 /*!
 114     \qmlproperty Animation QtQuick1::Behavior::animation
 115     \default
 116
 117     This property holds the animation to run when the behavior is triggered.
 118 */
 119
 120 QDeclarative1AbstractAnimation *QDeclarative1Behavior::animation()
 121 {
 122     Q_D(QDeclarative1Behavior);
 123     return d->animation;
 124 }
 125
 126 void QDeclarative1Behavior::setAnimation(QDeclarative1AbstractAnimation *animation)
 127 {
 128     Q_D(QDeclarative1Behavior);
 129     if (d->animation) {
 130         qmlInfo(this) << tr("Cannot change the animation assigned to a Behavior.");
 131         return;
 132     }
 133
 134     d->animation = animation;
 135     if (d->animation) {
 136         d->animation->setDefaultTarget(d->property);
 137         d->animation->setDisableUserControl();
 138         connect(d->animation->qtAnimation(),
 139                 SIGNAL(stateChanged(QAbstractAnimation::State,QAbstractAnimation::State)),
 140                 this,
 141                 SLOT(qtAnimationStateChanged(QAbstractAnimation::State,QAbstractAnimation::State)));
 142     }
 143 }
 144
 145
 146 void QDeclarative1Behavior::qtAnimationStateChanged(QAbstractAnimation::State newState,QAbstractAnimation::State)
 147 {
 148     Q_D(QDeclarative1Behavior);
 149     if (!d->blockRunningChanged)
 150         d->animation->notifyRunningChanged(newState == QAbstractAnimation::Running);
 151 }
 152
 153
 154 /*!
 155     \qmlproperty bool QtQuick1::Behavior::enabled
 156
 157     This property holds whether the behavior will be triggered when the tracked
 158     property changes value.
 159
 160     By default a Behavior is enabled.
 161 */
 162
 163 bool QDeclarative1Behavior::enabled() const
 164 {
 165     Q_D(const QDeclarative1Behavior);
 166     return d->enabled;
 167 }
 168
 169 void QDeclarative1Behavior::setEnabled(bool enabled)
 170 {
 171     Q_D(QDeclarative1Behavior);
 172     if (d->enabled == enabled)
 173         return;
 174     d->enabled = enabled;
 175     emit enabledChanged();
 176 }
 177
 178 void QDeclarative1Behavior::write(const QVariant &value)
 179 {
 180     Q_D(QDeclarative1Behavior);
 181     qmlExecuteDeferred(this);
 182     if (!d->animation || !d->enabled || !d->finalized) {
 183         QDeclarativePropertyPrivate::write(d->property, value, QDeclarativePropertyPrivate::BypassInterceptor | QDeclarativePropertyPrivate::DontRemoveBinding);
 184         d->targetValue = value;
 185         return;
 186     }
 187
 188     if (d->animation->isRunning() && value == d->targetValue)
 189         return;
 190
 191     d->currentValue = d->property.read();
 192     d->targetValue = value;
 193
 194     if (d->animation->qtAnimation()->duration() != -1
 195             && d->animation->qtAnimation()->state() != QAbstractAnimation::Stopped) {
 196         d->blockRunningChanged = true;
 197         d->animation->qtAnimation()->stop();
 198     }
 199
 200     QDeclarative1StateOperation::ActionList actions;
 201     QDeclarative1Action action;
 202     action.property = d->property;
 203     action.fromValue = d->currentValue;
 204     action.toValue = value;
 205     actions << action;
 206
 207     QList<QDeclarativeProperty> after;
 208     d->animation->transition(actions, after, QDeclarative1AbstractAnimation::Forward);
 209     d->animation->qtAnimation()->start();
 210     d->blockRunningChanged = false;
 211     if (!after.contains(d->property))
 212         QDeclarativePropertyPrivate::write(d->property, value, QDeclarativePropertyPrivate::BypassInterceptor | QDeclarativePropertyPrivate::DontRemoveBinding);
 213 }
 214
 215 void QDeclarative1Behavior::setTarget(const QDeclarativeProperty &property)
 216 {
 217     Q_D(QDeclarative1Behavior);
 218     d->property = property;
 219     d->currentValue = property.read();
 220     if (d->animation)
 221         d->animation->setDefaultTarget(property);
 222
 223     QDeclarativeEnginePrivate *engPriv = QDeclarativeEnginePrivate::get(qmlEngine(this));
 224     engPriv->registerFinalizeCallback(this, this->metaObject()->indexOfSlot("componentFinalized()"));
 225 }
 226
 227 void QDeclarative1Behavior::componentFinalized()
 228 {
 229     Q_D(QDeclarative1Behavior);
 230     d->finalized = true;
 231 }
 232
 233
 234
 235 QT_END_NAMESPACE