src/quick/util/qdeclarativepackage.cpp

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  41
  42 #include "qdeclarativepackage_p.h"
  43
  44 #include <private/qobject_p.h>
  45 #include <private/qdeclarativeguard_p.h>
  46
  47 QT_BEGIN_NAMESPACE
  48
  49 /*!
  50     \qmlclass Package QDeclarativePackage
  51     \inqmlmodule QtQuick 2
  52     \ingroup qml-working-with-data
  53     \brief Package provides a collection of named items.
  54
  55     The Package class is used in conjunction with
  56     VisualDataModel to enable delegates with a shared context
  57     to be provided to multiple views.
  58
  59     Any item within a Package may be assigned a name via the
  60     \l{Package::name}{Package.name} attached property.
  61
  62     The example below creates a Package containing two named items;
  63     \e list and \e grid.  The third element in the package (the \l Rectangle) is parented to whichever
  64     delegate it should appear in.  This allows an item to move
  65     between views.
  66
  67     \snippet examples/declarative/modelviews/package/Delegate.qml 0
  68
  69     These named items are used as the delegates by the two views who
  70     reference the special \l{VisualDataModel::parts} property to select
  71     a model which provides the chosen delegate.
  72
  73     \snippet examples/declarative/modelviews/package/view.qml 0
  74
  75     \sa {declarative/modelviews/package}{Package example}, {declarative/photoviewer}{Photo Viewer example}, QtDeclarative
  76 */
  77
  78 /*!
  79     \qmlattachedproperty string QtQuick2::Package::name
  80     This attached property holds the name of an item within a Package.
  81 */
  82
  83
  84 class QDeclarativePackagePrivate : public QObjectPrivate
  85 {
  86 public:
  87     QDeclarativePackagePrivate() {}
  88
  89     struct DataGuard : public QDeclarativeGuard<QObject>
  90     {
  91         DataGuard(QObject *obj, QList<DataGuard> *l) : list(l) { (QDeclarativeGuard<QObject>&)*this = obj; }
  92         QList<DataGuard> *list;
  93         void objectDestroyed(QObject *) {
  94             // we assume priv will always be destroyed after objectDestroyed calls
  95             list->removeOne(*this);
  96         }
  97     };
  98
  99     QList<DataGuard> dataList;
 100     static void data_append(QDeclarativeListProperty<QObject> *prop, QObject *o) {
 101         QList<DataGuard> *list = static_cast<QList<DataGuard> *>(prop->data);
 102         list->append(DataGuard(o, list));
 103     }
 104     static void data_clear(QDeclarativeListProperty<QObject> *prop) {
 105         QList<DataGuard> *list = static_cast<QList<DataGuard> *>(prop->data);
 106         list->clear();
 107     }
 108     static QObject *data_at(QDeclarativeListProperty<QObject> *prop, int index) {
 109         QList<DataGuard> *list = static_cast<QList<DataGuard> *>(prop->data);
 110         return list->at(index);
 111     }
 112     static int data_count(QDeclarativeListProperty<QObject> *prop) {
 113         QList<DataGuard> *list = static_cast<QList<DataGuard> *>(prop->data);
 114         return list->count();
 115     }
 116 };
 117
 118 QHash<QObject *, QDeclarativePackageAttached *> QDeclarativePackageAttached::attached;
 119
 120 QDeclarativePackageAttached::QDeclarativePackageAttached(QObject *parent)
 121 : QObject(parent)
 122 {
 123     attached.insert(parent, this);
 124 }
 125
 126 QDeclarativePackageAttached::~QDeclarativePackageAttached()
 127 {
 128     attached.remove(parent());
 129 }
 130
 131 QString QDeclarativePackageAttached::name() const
 132 {
 133     return _name;
 134 }
 135
 136 void QDeclarativePackageAttached::setName(const QString &n)
 137 {
 138     _name = n;
 139 }
 140
 141 QDeclarativePackage::QDeclarativePackage(QObject *parent)
 142     : QObject(*(new QDeclarativePackagePrivate), parent)
 143 {
 144 }
 145
 146 QDeclarativePackage::~QDeclarativePackage()
 147 {
 148     Q_D(QDeclarativePackage);
 149     for (int ii = 0; ii < d->dataList.count(); ++ii) {
 150         QObject *obj = d->dataList.at(ii);
 151         obj->setParent(this);
 152     }
 153 }
 154
 155 QDeclarativeListProperty<QObject> QDeclarativePackage::data()
 156 {
 157     Q_D(QDeclarativePackage);
 158     return QDeclarativeListProperty<QObject>(this, &d->dataList, QDeclarativePackagePrivate::data_append,
 159                                                         QDeclarativePackagePrivate::data_count,
 160                                                         QDeclarativePackagePrivate::data_at,
 161                                                         QDeclarativePackagePrivate::data_clear);
 162 }
 163
 164 bool QDeclarativePackage::hasPart(const QString &name)
 165 {
 166     Q_D(QDeclarativePackage);
 167     for (int ii = 0; ii < d->dataList.count(); ++ii) {
 168         QObject *obj = d->dataList.at(ii);
 169         QDeclarativePackageAttached *a = QDeclarativePackageAttached::attached.value(obj);
 170         if (a && a->name() == name)
 171             return true;
 172     }
 173     return false;
 174 }
 175
 176 QObject *QDeclarativePackage::part(const QString &name)
 177 {
 178     Q_D(QDeclarativePackage);
 179     if (name.isEmpty() && !d->dataList.isEmpty())
 180         return d->dataList.at(0);
 181
 182     for (int ii = 0; ii < d->dataList.count(); ++ii) {
 183         QObject *obj = d->dataList.at(ii);
 184         QDeclarativePackageAttached *a = QDeclarativePackageAttached::attached.value(obj);
 185         if (a && a->name() == name)
 186             return obj;
 187     }
 188
 189     if (name == QLatin1String("default") && !d->dataList.isEmpty())
 190         return d->dataList.at(0);
 191
 192     return 0;
 193 }
 194
 195 QDeclarativePackageAttached *QDeclarativePackage::qmlAttachedProperties(QObject *o)
 196 {
 197     return new QDeclarativePackageAttached(o);
 198 }
 199
 200
 201
 202 QT_END_NAMESPACE