KisResourceMetaDataModel Class Reference

#include <KisResourceMetaDataModel.h>

Classes
struct	Private

Public Member Functions
	KisResourceMetaDataModel (const QString &tableName)
QVariant	metaDataValue (int resourceId, const QString &key)
	~KisResourceMetaDataModel ()

Private Attributes
QScopedPointer< Private >	m_d

Detailed Description

simple class used for fetching specific metadata for a resource. Internally it stores a prepared query that can fetch particular metadata keys in an efficiant way.

In contrast to KisAbstractResourceModel::MetaData role in the resource model this class allows fetching individual keys from the resource's metadata. That is usually more efficient in some cases.

The rule of thumb: if you want to fetch all metadata for resource, use KisAbstractResourceModel::MetaData, if you want an individual key, use KisResourceMetaDataModel.

Definition at line 28 of file KisResourceMetaDataModel.h.

Constructor & Destructor Documentation

KisResourceMetaDataModel()

KisResourceMetaDataModel::KisResourceMetaDataModel

(

const QString &

tableName

)

Definition at line 16 of file KisResourceMetaDataModel.cpp.

    : m_d(new Private)
{
    m_d->query.setForwardOnly(true);
 
    m_d->isQueryPrepared =
        m_d->query.prepare(
            "SELECT value\n"
            "FROM   metadata\n"
            "WHERE  foreign_id = :id\n"
            "AND    table_name = :table\n"
            "AND    key = :key\n"
            "LIMIT 1");
 
    if (!m_d->isQueryPrepared) {
        qWarning() << "Could not prepare metadata query" << m_d->query.lastError();
        return;
    } else {
        m_d->query.bindValue(":table", tableName);
    }
}

References m_d.

~KisResourceMetaDataModel()

KisResourceMetaDataModel::~KisResourceMetaDataModel

(

)

Definition at line 38 of file KisResourceMetaDataModel.cpp.

{
}

Member Function Documentation

metaDataValue()

QVariant KisResourceMetaDataModel::metaDataValue	(	int	resourceId,
		const QString &	key )

Definition at line 42 of file KisResourceMetaDataModel.cpp.

{
    QVariant resultValue;
    
    if (!m_d->isQueryPrepared) return resultValue;
 
    m_d->query.bindValue(":id", resourceId);
    m_d->query.bindValue(":key", key);
 
    if (!m_d->query.exec()) {
        qWarning() << "Could not execute metadata query" << m_d->query.lastError();
        return resultValue;
    }
 
    if (m_d->query.size() > 1) {
        qWarning() << "Found duplicated entries for metadata for resource" << resourceId << "and key" << key;
    }
 
    if (m_d->query.first()) {
        QByteArray ba = m_d->query.value(0).toByteArray();
        if (!ba.isEmpty()) {
            QDataStream ds(QByteArray::fromBase64(ba));
            QVariant value;
            ds >> value;
            resultValue = value;
        }
    }
 
    return resultValue;
}

References m_d, and value().

Member Data Documentation

m_d

QScopedPointer<Private> KisResourceMetaDataModel::m_d

private

Definition at line 38 of file KisResourceMetaDataModel.h.

---

The documentation for this class was generated from the following files:

• libs/resources/KisResourceMetaDataModel.h
• libs/resources/KisResourceMetaDataModel.cpp