path: root/src/imports/location/qdeclarativegeomapitemview.cpp

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#include "qdeclarativegeomapitemview_p.h"
#include "qdeclarativegeomapmousearea_p.h"
#include "qdeclarativegeomap_p.h"
#include "qdeclarativegeomapitembase_p.h"

#include <QDeclarativeParserStatus>
#include <QAbstractItemModel>
#include <QDeclarativeContext>

QT_BEGIN_NAMESPACE

/*!
    \qmlclass MapItemView QDeclarativeGeoMapItemView
    \inqmlmodule QtLocation 5
    \ingroup qml-QtLocation5-maps
    \since QtLocation 5.0
    \inherits QQuickItem

    \brief The MapItemView is used to populate Map from a model.

    The MapItemView is used to populate Map with MapItems from a model.
    The MapItemView element only makes sense when contained in a Map,
    meaning that it has no standalone presentation.
*/

QDeclarativeGeoMapItemView::QDeclarativeGeoMapItemView(QQuickItem *parent)
    : QObject(parent), visible_(true), componentCompleted_(false), delegate_(0),
      model_(0), map_(0)
{
}

QDeclarativeGeoMapItemView::~QDeclarativeGeoMapItemView()
{
    if (map_)
        removeInstantiatedItems();
}

void QDeclarativeGeoMapItemView::componentComplete()
{
    componentCompleted_ = true;
}

QVariant QDeclarativeGeoMapItemView::model() const
{
    return modelVariant_;
}

/*!
    \qmlproperty model QtLocation5::MapItemView::model

    This property holds the model that provides data for
    populating data with delegates.
*/

void QDeclarativeGeoMapItemView::setModel(const QVariant &model)
{
    if (!model.isValid() || model == modelVariant_)
        return;
    QObject *object = qvariant_cast<QObject*>(model);
    QAbstractItemModel* itemModel;
    if (!object || !(itemModel = qobject_cast<QAbstractItemModel*>(object))) {
        return;
    }
    modelVariant_ = model;
    model_ = itemModel;
    // At the moment maps only works with selected models. Because of this tight
    // restriction, we are not listening to all change signals.
    QObject::connect(model_, SIGNAL(modelReset()), this, SLOT(modelReset()));
    QObject::connect(model_, SIGNAL(rowsRemoved(QModelIndex, int, int)), this, SLOT(modelRowsRemoved(QModelIndex, int, int)));
    QObject::connect(model_, SIGNAL(rowsInserted(QModelIndex, int, int)), this, SLOT(modelRowsInserted(QModelIndex, int, int)));
    repopulate();
    emit modelChanged();
}

void QDeclarativeGeoMapItemView::modelReset()
{
    repopulate();
}

void QDeclarativeGeoMapItemView::modelRowsInserted(QModelIndex, int start, int end)
{
    if (!componentCompleted_ || !map_ || !delegate_ || !model_) {
        QDeclarativeGeoMapItemBase* mapItem;
        for (int i = start; i <= end; ++i) {
            mapItem = createItem(i);
            if (!mapItem) {
                break;
            }
            mapItemList_.append(mapItem);
            map_->addMapItem(mapItem);
        }
    }
}

void QDeclarativeGeoMapItemView::modelRowsRemoved(QModelIndex, int start, int end)
{
    if (!componentCompleted_ || !map_ || !delegate_ || !model_)
        return;
    for (int i = end; i >= start; --i) {
        QDeclarativeGeoMapItemBase *mapItem = mapItemList_.takeAt(i);
        Q_ASSERT(mapItem);
        if (!mapItem) // bad
            break;
        map_->removeMapItem(mapItem);
        delete mapItem;
    }
}

QDeclarativeComponent* QDeclarativeGeoMapItemView::delegate() const
{
    return delegate_;
}

/*!
    \qmlproperty Component QtLocation5::MapItemView::delegate

    This property holds the delegate which defines how each item in the
    model should be displayed. The Component must contain exactly one
    MapItem -derived element as the root element.

*/

void QDeclarativeGeoMapItemView::setDelegate(QDeclarativeComponent *delegate)
{
    if (!delegate)
        return;
    delegate_ = delegate;

    repopulate();
    emit delegateChanged();
}

//void QDeclarativeGeoMapItemView::setMapData(QDeclarativeGraphicsGeoMap* map)
void QDeclarativeGeoMapItemView::setMapData(QDeclarativeGeoMap* map)
{
    if (!map || map_) // changing map on the fly not supported
        return;
    map_ = map;
}

void QDeclarativeGeoMapItemView::removeInstantiatedItems()
{
    if (!map_)
        return;
    for (int i = 0; i < mapItemList_.count(); ++ i) {
        map_->removeMapItem(mapItemList_.at(i));
    }
    qDeleteAll(mapItemList_);
    mapItemList_.clear();
}

// Removes and repopulates all items.
void QDeclarativeGeoMapItemView::repopulate()
{
    if (!componentCompleted_ || !map_ || !delegate_ || !model_)
        return;
    // Free any earlier instances
    removeInstantiatedItems();

    // Iterate model data and instantiate delegates.
    // We could use more specialized landmark model calls here too,
    // but hopefully the support will be leveraged to a general model
    // level.
    QDeclarativeGeoMapItemBase* mapItem;
    for (int i = 0; i < model_->rowCount(); ++i) {
        mapItem = createItem(i);
        Q_ASSERT(mapItem);
        if (!mapItem) // bad
            break;
        mapItemList_.append(mapItem);
        map_->addMapItem(mapItem);
    }
}

// Currently item creation is tightly bound to models providing
// QObject* as data. Some day this may be leveraged to any user defined
// model or e.g. XML model.
//QDeclarativeGeoMapItem* QDeclarativeGeoMapItemView::createItem(int modelRow)
QDeclarativeGeoMapItemBase* QDeclarativeGeoMapItemView::createItem(int modelRow)
{
    if (!delegate_ || !model_)
        return NULL;
    QModelIndex index = model_->index(modelRow, 0); // column 0
    if (!index.isValid()) {
        qWarning() << "QDeclarativeGeoMapItemView Index is not valid: " << modelRow;
        return NULL;
    }
    QHashIterator<int, QByteArray> iterator(model_->roleNames());
    QDeclarativeContext *itemContext = new QDeclarativeContext(qmlContext(this));
    while (iterator.hasNext()) {
        iterator.next();
        QVariant modelData = model_->data(index, iterator.key());
        if (!modelData.isValid())
            continue;

        // Currently we only support QObject* type data.
        QObject* data_ptr = modelData.value<QObject*>();

        if (!data_ptr)
            continue;
        itemContext->setContextProperty(QLatin1String(iterator.value().data()), data_ptr);
        itemContext->setContextProperty(QLatin1String("model"), data_ptr);
        // To avoid name collisions (delegate has same named attribute as model's role)
        // one can add here that the data is accessible also e.g. via 'model'.
        // However this requires instantiating a dynamic qobject and assigning it the
        // dynamic property as property. Dynamic meta object code from declarative
        // code should be reused. In mobility, e.g. contacts should have an example.
    }
    QObject* obj = delegate_->create(itemContext);

    if (!obj) {
        qWarning() << "QDeclarativeGeoMapItemView map item creation failed.";
        delete itemContext;
        return 0;
    }
    QDeclarativeGeoMapItemBase *declMapObj =  qobject_cast<QDeclarativeGeoMapItemBase*>(obj);
    if (!declMapObj) {
        qWarning() << "QDeclarativeGeoMapItemView map item delegate is of unsupported type.";
        delete itemContext;
        return 0;
    }
    itemContext->setParent(declMapObj);
    return declMapObj;
}

/*!
    \qmlproperty bool QtLocation5::MapItemView::visible

    This property holds whether the delegate objects created from the
    model are visible or not. Default value is true.

*/

void QDeclarativeGeoMapItemView::setVisible(bool visible)
{
    // TODO!
    Q_UNUSED(visible);
}

bool QDeclarativeGeoMapItemView::isVisible() const
{
    return visible_;
}

/*!
    \qmlproperty int QtLocation5::MapItemView::z

    This property holds the z-value of the MapItemView.
    It determines the z-value of the instantiated delegates.

    As with other Map items, objects with same z-value are
    drawn in insertion order.

*/

void QDeclarativeGeoMapItemView::setZValue(qreal zValue)
{
    // TODO z values
    Q_UNUSED(zValue);
    // group_.setZValue(zValue);
    // emit zChanged();
}

qreal QDeclarativeGeoMapItemView::zValue()
{
    // TODO z values what to do
    return 1.0;
    //return group_.zValue();
}

#include "moc_qdeclarativegeomapitemview_p.cpp"

QT_END_NAMESPACE