q3sqlselectcursor.cpp

奇趣公司比较新的qt/emd版本

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#include "q3sqlselectcursor.h"
#include "qsqldriver.h"
#include "q3sqlrecordinfo.h"

#ifndef QT_NO_SQL

class Q3SqlSelectCursorPrivate
{
public:
    Q3SqlSelectCursorPrivate() : populated(false) {}
    QString query;
    bool populated : 1;
};

/*!
    \class Q3SqlSelectCursor qsqlselectcursor.h
    \brief The Q3SqlSelectCursor class provides browsing of general SQL SELECT statements.

    \compat

    Q3SqlSelectCursor is a convenience class that makes it possible to
    display result sets from general SQL \c SELECT statements in
    data-aware Qt widgets. Q3SqlSelectCursor is read-only and does not
    support \c INSERT, \c UPDATE or \c DELETE operations.

    Pass the query in at construction time, or use the
    Q3SqlSelectCursor::exec() function.

    Example:
    \code
    ...
    Q3SqlSelectCursor* cur = new Q3SqlSelectCursor("SELECT id, firstname, lastname FROM author");
    Q3DataTable* table = new Q3DataTable(this);
    table->setSqlCursor(cur, true, true);
    table->refresh();
    ...
    cur->exec("SELECT * FROM books");
    table->refresh();
    ...
    \endcode
*/

/*!
    Constructs a read only cursor on database \a db using the query \a query.
 */
Q3SqlSelectCursor::Q3SqlSelectCursor(const QString& query, QSqlDatabase db)
    : Q3SqlCursor(QString(), false, db)
{
    d = new Q3SqlSelectCursorPrivate;
    d->query = query;
    Q3SqlCursor::setMode(ReadOnly);
    if (!query.isEmpty())
        exec(query);
}

/*! Constructs a copy of \a other */
Q3SqlSelectCursor::Q3SqlSelectCursor(const Q3SqlSelectCursor& other)
    : Q3SqlCursor(other)
{
    d = new Q3SqlSelectCursorPrivate;
    d->query = other.d->query;
    d->populated = other.d->populated;
}

/*! Destroys the object and frees any allocated resources */
Q3SqlSelectCursor::~Q3SqlSelectCursor()
{
    delete d;
}

/*! \internal */
bool Q3SqlSelectCursor::exec(const QString& query)
{
    d->query = query;
    bool ret = Q3SqlCursor::exec(query);
    if (ret) {
        Q3SqlCursor::clear();
        populateCursor();
    }
    return ret;
}

/*! \fn bool Q3SqlSelectCursor::select()
    \internal
*/

/*! \internal */
bool Q3SqlSelectCursor::select(const QString&, const QSqlIndex&)
{
    bool ret = Q3SqlCursor::exec(d->query);
    if (ret && !d->populated)
        populateCursor();
    return ret;
}

/*! \internal */
void Q3SqlSelectCursor::populateCursor()
{
    Q3SqlRecordInfo inf = Q3SqlRecordInfo(record());
    for (Q3SqlRecordInfo::const_iterator it = inf.begin(); it != inf.end(); ++it)
        Q3SqlCursor::append(*it);
    d->populated = true;
}

/*! \fn QSqlIndex Q3SqlSelectCursor::primaryIndex(bool) const
    \internal
*/

/*! \fn QSqlIndex Q3SqlSelectCursor::index(const QStringList&) const
    \internal
*/

/*! \fn QSqlIndex Q3SqlSelectCursor::index(const QString&) const
    \internal
*/

/*! \fn QSqlIndex Q3SqlSelectCursor::index(const char*) const
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setPrimaryIndex(const QSqlIndex&)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::append(const Q3SqlFieldInfo&)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::insert(int, const Q3SqlFieldInfo&)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::remove(int)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::clear()
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setGenerated(const QString&, bool)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setGenerated(int, bool)
    \internal
*/

/*! \fn QSqlRecord* Q3SqlSelectCursor::editBuffer(bool)
    \internal
*/

/*! \fn QSqlRecord* Q3SqlSelectCursor::primeInsert()
    \internal
*/

/*! \fn QSqlRecord* Q3SqlSelectCursor::primeUpdate()
    \internal
*/

/*! \fn QSqlRecord* Q3SqlSelectCursor::primeDelete()
    \internal
*/

/*! \fn int Q3SqlSelectCursor::insert(bool)
    \internal
*/

/*! \fn int Q3SqlSelectCursor::update(bool)
    \internal
*/

/*! \fn int Q3SqlSelectCursor::del(bool)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setMode(int)
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setSort(const QSqlIndex&)
    \internal
*/

/*! \fn QSqlIndex Q3SqlSelectCursor::sort() const
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setFilter(const QString&)
    \internal
*/

/*! \fn QString Q3SqlSelectCursor::filter() const
    \internal
*/

/*! \fn void Q3SqlSelectCursor::setName(const QString&, bool)
    \internal
*/

/*! \fn QString Q3SqlSelectCursor::name() const
    \internal
*/

/*! \fn QString Q3SqlSelectCursor::toString(const QString&, const QString&) const
    \internal
*/

/*!
    \fn int Q3SqlSelectCursor::update(const QString & filter, bool invalidate = true)

    \overload

    Updates the database with the current contents of the cursor edit
    buffer using the specified \a filter. Returns the number of
    records which were updated.
    For error information, use lastError().

    Only records which meet the filter criteria are updated, otherwise
    all records in the table are updated.

    If \a invalidate is true (the default), the cursor can no longer
    be navigated. A new select() call must be made before you can move
    to a valid record.

    \sa Q3SqlCursor::update() primeUpdate() setMode() lastError()
*/
#endif // QT_NO_SQL