q3datatable.cpp

奇趣公司比较新的qt/emd版本

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#include "q3datatable.h"

#ifndef QT_NO_SQL_VIEW_WIDGETS

#include "qevent.h"
#include "qsqldriver.h"
#include "q3sqleditorfactory.h"
#include "q3sqlpropertymap.h"
#include "qapplication.h"
#include "qlayout.h"
#include "qpainter.h"
#include "q3popupmenu.h"
#include "q3valuelist.h"
#include "q3sqlmanager_p.h"
#include "qsqlfield.h"
#include "qdatetime.h"
#include "qcursor.h"
#include "qtimer.h"
#include "qpointer.h"

//#define QT_DEBUG_DATATABLE

class Q3DataTablePrivate
{
public:
    Q3DataTablePrivate()
	: nullTxtChanged( false ),
	  haveAllRows( false ),
	  continuousEdit( false ),
	  editorFactory( 0 ),
	  propertyMap( 0 ),
	  editRow( -1 ),
	  editCol( -1 ),
	  insertRowLast( -1 ),
	  insertPreRows( -1 ),
	  editBuffer( 0 ),
	  cancelMode( false ),
	  cancelInsert( false ),
	  cancelUpdate( false )
    {}
    ~Q3DataTablePrivate() { if ( propertyMap ) delete propertyMap; }

    QString nullTxt;
    bool nullTxtChanged;
    typedef Q3ValueList< uint > ColIndex;
    ColIndex colIndex;
    bool haveAllRows;
    bool continuousEdit;
    Q3SqlEditorFactory* editorFactory;
    Q3SqlPropertyMap* propertyMap;
    QString trueTxt;
    Qt::DateFormat datefmt;
    QString falseTxt;
    int editRow;
    int editCol;
    int insertRowLast;
    QString insertHeaderLabelLast;
    int insertPreRows;
    QSqlRecord* editBuffer;
    bool cancelMode;
    bool cancelInsert;
    bool cancelUpdate;
    int lastAt;
    QString ftr;
    QStringList srt;
    QStringList fld;
    QStringList fldLabel;
    Q3ValueList<int> fldWidth;
    Q3ValueList<QIconSet> fldIcon;
    Q3ValueList<bool> fldHidden;
    Q3SqlCursorManager cur;
    Q3DataManager dat;
};

#ifdef QT_DEBUG_DATATABLE
void qt_debug_buffer( const QString& msg, QSqlRecord* cursor )
{
    qDebug("+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++");
    qDebug(msg);
    for ( uint j = 0; j < cursor->count(); ++j ) {
	qDebug(cursor->field(j)->name() + " type:" + QString(cursor->field(j)->value().typeName()) + " value:" + cursor->field(j)->value().toString() );
    }
}
#endif

/*!
    \enum Q3DataTable::Refresh

    This enum describes the refresh options.

    \value RefreshData  refresh the data, i.e. read it from the database
    \value RefreshColumns  refresh the list of fields, e.g. the column headings
    \value RefreshAll  refresh both the data and the list of fields
*/


/*!
    \class Q3DataTable qdatatable.h
    \brief The Q3DataTable class provides a flexible SQL table widget that supports browsing and editing.

    \compat

    Q3DataTable supports various functions for presenting and editing
    SQL data from a \l Q3SqlCursor in a table.

    If you want a to present your data in a form use QDataBrowser, or
    for read-only forms, use QDataView instead.

    When displaying data, Q3DataTable only retrieves data for visible
    rows. If the driver supports the 'query size' property the
    Q3DataTable will have the correct number of rows and the vertical
    scroll bar will accurately reflect the number of rows displayed in
    proportion to the number of rows in the dataset. If the driver
    does not support the 'query size' property, rows are dynamically
    fetched from the database on an as-needed basis with the scroll bar
    becoming more accurate as the user scrolls down through the
    records. This allows extremely large queries to be displayed as
    quickly as possible, with minimum memory usage.

    Q3DataTable inherits Q3Table's API and extends it with functions to
    sort and filter the data and sort columns. See setSqlCursor(),
    setFilter(), setSort(), setSorting(), sortColumn() and refresh().

    When displaying editable cursors, cell editing will be enabled.
    (For more information on editable cursors, see \l Q3SqlCursor).
    Q3DataTable can be used to modify existing data and to add new
    records. When a user makes changes to a field in the table, the
    cursor's edit buffer is used. The table will not send changes in
    the edit buffer to the database until the user moves to a
    different record in the grid or presses Enter. Cell editing is
    initiated by pressing F2 (or right clicking and then clicking the
    appropriate popup menu item) and canceled by pressing Esc. If
    there is a problem updating or adding data, errors are handled
    automatically (see handleError() to change this behavior). Note
    that if autoEdit() is false navigating to another record will
    cancel the insert or update.

    The user can be asked to confirm all edits with setConfirmEdits().
    For more precise control use setConfirmInsert(),
    setConfirmUpdate(), setConfirmDelete() and setConfirmCancels().
    Use setAutoEdit() to control the behavior of the table when the
    user edits a record and then navigates. (Note that setAutoDelete()
    is unrelated; it is used to set whether the Q3SqlCursor is deleted
    when the table is deleted.)

    Since the data table can perform edits, it must be able to
    uniquely identify every record so that edits are correctly
    applied. Because of this the underlying cursor must have a valid
    primary index to ensure that a unique record is inserted, updated
    or deleted within the database otherwise the database may be
    changed to an inconsistent state.

    Q3DataTable creates editors using the default \l Q3SqlEditorFactory.
    Different editor factories can be used by calling
    installEditorFactory(). A property map is used to map between the
    cell's value and the editor. You can use your own property map
    with installPropertyMap().

    The contents of a cell is available as a QString with text() or as
    a QVariant with value(). The current record is returned by
    currentRecord(). Use the find() function to search for a string in
    the table.

    Editing actions can be applied programmatically. For example, the
    insertCurrent() function reads the fields from the current record
    into the cursor and performs the insert. The updateCurrent() and
    deleteCurrent() functions perform similarly to update and delete
    the current record respectively.

    Columns in the table can be created automatically based on the
    cursor (see setSqlCursor()). Columns can be manipulated manually
    using addColumn(), removeColumn() and setColumn().

    The table automatically copies many of the properties of the
    cursor to format the display of data within cells (alignment,
    visibility, etc.). The cursor can be changed with setSqlCursor().
    The filter (see setFilter()) and sort defined within the table are
    used instead of the filter and sort set on the cursor. For sorting
    options see setSort(), sortColumn(), sortAscending() and
    sortDescending(). Note that sorting operations will not behave as
    expected if you are using a QSqlSelectCursor because it uses
    user-defined SQL queries to obtain data.

    The text used to represent NULL, true and false values can be
    changed with setNullText(), setTrueText() and setFalseText()
    respectively. You can change the appearance of cells by
    reimplementing paintField().

    Whenever a new row is selected in the table the currentChanged()
    signal is emitted. The primeInsert() signal is emitted when an
    insert is initiated. The primeUpdate() and primeDelete() signals
    are emitted when update and deletion are initiated respectively.
    Just before the database is updated a signal is emitted;
    beforeInsert(), beforeUpdate() or beforeDelete() as appropriate.

*/

/*!
    Constructs a data table which is a child of \a parent, called
    name \a name.
*/

Q3DataTable::Q3DataTable ( QWidget * parent, const char * name )
    : Q3Table( parent, name )
{
    init();
}

/*!
    Constructs a data table which is a child of \a parent, called name
    \a name using the cursor \a cursor.

    If \a autoPopulate is true (the default is false), columns are
    automatically created based upon the fields in the \a cursor
    record. Note that \a autoPopulate only governs the creation of
    columns; to load the cursor's data into the table use refresh().

    If the \a cursor is read-only, the table also becomes read-only.
    In addition, the table adopts the cursor's driver's definition for
    representing NULL values as strings.
*/

Q3DataTable::Q3DataTable ( Q3SqlCursor* cursor, bool autoPopulate, QWidget * parent, const char * name )
    : Q3Table( parent, name )
{
    init();
    setSqlCursor( cursor, autoPopulate );
}

/*! \internal
*/


void Q3DataTable::init()
{
    d = new Q3DataTablePrivate();
    setAutoEdit( true );
    setSelectionMode( SingleRow );
    setFocusStyle( FollowStyle );
    d->trueTxt = tr( "True" );
    d->falseTxt = tr( "False" );
    d->datefmt = Qt::LocalDate;
    reset();
    connect( this, SIGNAL(selectionChanged()),
	     SLOT(updateCurrentSelection()));
}

/*!
    Destroys the object and frees any allocated resources.
*/

Q3DataTable::~Q3DataTable()
{
    delete d;
}


/*!
    Adds the next column to be displayed using the field \a fieldName,
    column label \a label, width \a width and iconset \a iconset.

    If \a label is specified, it is used as the column's header label,
    otherwise the field's display label is used when setSqlCursor() is
    called. The \a iconset is used to set the icon used by the column
    header; by default there is no icon.

    \sa setSqlCursor() refresh()
*/

void Q3DataTable::addColumn( const QString& fieldName,
			    const QString& label,
			    int width,
			    const QIconSet& iconset )
{
    d->fld += fieldName;
    d->fldLabel += label;
    d->fldIcon += iconset;
    d->fldWidth += width;
    d->fldHidden += false;
}

/*!
    Sets the \a col column to display using the field \a fieldName,
    column label \a label, width \a width and iconset \a iconset.

    If \a label is specified, it is used as the column's header label,
    otherwise the field's display label is used when setSqlCursor() is
    called. The \a iconset is used to set the icon used by the column
    header; by default there is no icon.

    \sa setSqlCursor() refresh()
*/

void Q3DataTable::setColumn( uint col, const QString& fieldName,
			    const QString& label,
			    int width,
			    const QIconSet& iconset )
{
    d->fld[col]= fieldName;
    d->fldLabel[col] = label;
    d->fldIcon[col] = iconset;
    d->fldWidth[col] = width;
    d->fldHidden[col] = false;
}

/*!
    Removes column \a col from the list of columns to be displayed. If
    \a col does not exist, nothing happens.

    \sa QSqlField
*/

void Q3DataTable::removeColumn( int col )
{
    if ( d->fld.begin() + col != d->fld.end() ) {
	d->fld.remove( d->fld.at( col ) );
	d->fldLabel.remove( d->fldLabel.at( col ) );
	d->fldIcon.remove( d->fldIcon.at( col ) );
	d->fldWidth.remove( d->fldWidth.at( col ) );
	d->fldHidden.remove( d->fldHidden.at( col ) );
    }
}

/*!
    Sets the column \a col to the width \a w. Note that unlike Q3Table
    the Q3DataTable is not immediately redrawn, you must call
    refresh(Q3DataTable::RefreshColumns)
    yourself.

    \sa refresh()
*/
void Q3DataTable::setColumnWidth( int col, int w )
{
    if ( d->fldWidth.at( col ) != d->fldWidth.end() ) {
	d->fldWidth[col] = w;
    }
}

/*!
    Resizes column \a col so that the column width is wide enough to
    display the widest item the column contains (including the column
    label). If the table's Q3SqlCursor is not currently active, the
    cursor will be refreshed before the column width is calculated. Be
    aware that this function may be slow on tables that contain large
    result sets.
*/
void Q3DataTable::adjustColumn( int col )
{
    Q3SqlCursor * cur = sqlCursor();
    if ( !cur || cur->count() <= col )
	return;
    if ( !cur->isActive() ) {
	d->cur.refresh();
    }
    int oldRow = currentRow();
    int w = fontMetrics().width( horizontalHeader()->label( col ) + QLatin1Char('W') );
    cur->seek( QSql::BeforeFirst );
    while ( cur->next() ) {
	w = QMAX( w, fontMetrics().width( fieldToString( cur->fieldPtr( indexOf( col ) ) ) ) + 10 );
    }
    setColumnWidth( col, w );
    cur->seek( oldRow );
    refresh( RefreshColumns );
}

/*! \reimp
*/
void Q3DataTable::setColumnStretchable( int col, bool s )
{
    if ( numCols() == 0 ) {
	refresh( RefreshColumns );
    }
    if ( numCols() > col ) {
	Q3Table::setColumnStretchable( col, s );
    }
}

QString Q3DataTable::filter() const
{
    return d->cur.filter();
}

/*!
    \property Q3DataTable::filter
    \brief the data filter for the data table

    The filter applies to the data shown in the table. To view data
    with a new filter, use refresh(). A filter string is an SQL WHERE
    clause without the WHERE keyword.

    There is no default filter.

    \sa sort()

*/

void Q3DataTable::setFilter( const QString& filter )
{
    d->cur.setFilter( filter );
}


/*!
    \property Q3DataTable::sort
    \brief the data table's sort

    The table's sort affects the order in which data records are
    displayed in the table. To apply a sort, use refresh().

    When examining the sort property, a string list is returned with
    each item having the form 'fieldname order' (e.g., 'id ASC',
    'surname DESC').

    There is no default sort.

    Note that if you want to iterate over the sort list, you should
    iterate over a copy, e.g.
    \code
    QStringList list = myDataTable.sort();
    QStringList::Iterator it = list.begin();
    while( it != list.end() ) {
	myProcessing( *it );
	++it;
    }
    \endcode

    \sa filter() refresh()
*/

void Q3DataTable::setSort( const QStringList& sort )
{