kexidataiteminterface.h

/* This file is part of the KDE project
   Copyright (C) 2005-2006 Jaroslaw Staniek <js@iidea.pl>
 
   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
 
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.
 
   You should have received a copy of the GNU Library General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/
 
#ifndef KEXIDATAITEMINTERFACE_H
#define KEXIDATAITEMINTERFACE_H
 
#include <tqvariant.h>
#include <tqwidget.h>
#include <tqguardedptr.h>
 
class KexiDataItemInterface;
namespace KexiDB {
    class Field;
    class QueryColumnInfo;
}

class KEXICORE_EXPORT KexiDataItemChangesListener
{
    public:
        KexiDataItemChangesListener();
        virtual ~KexiDataItemChangesListener();

        virtual void valueChanged(KexiDataItemInterface* item) = 0;

        virtual bool cursorAtNewRow() const = 0;
};

class KEXICORE_EXPORT KexiDataItemInterface
{
    public:
        KexiDataItemInterface();
        virtual ~KexiDataItemInterface();

        void setValue(const TQVariant& value, const TQVariant& add = TQVariant(), bool removeOld = false, 
            const TQVariant* visibleValue = 0);

        virtual KexiDB::Field *field() const = 0;

        virtual KexiDB::QueryColumnInfo* columnInfo() const = 0;

        virtual void setColumnInfo(KexiDB::QueryColumnInfo* cinfo) = 0;

        virtual void installListener(KexiDataItemChangesListener* listener);
 
//      //! Sets value \a value for a widget. 
//      //! Just calls setValueInternal(), but also blocks valueChanged() 
//      //! as you we don't want to react on our own change
//      void setValue(const TQVariant& value);

        virtual TQVariant value() = 0;

        virtual bool valueIsValid();

        virtual bool valueIsNull() = 0;

        virtual bool valueIsEmpty() = 0;

        virtual TQVariant visibleValue() { return TQVariant(); }

        virtual bool isReadOnly() const { return false; }

        virtual TQWidget* widget() = 0;

        virtual void hideWidget() { if (widget()) widget()->hide(); }

        virtual void showWidget() { if (widget()) widget()->show(); }

        virtual bool valueChanged();

        virtual bool cursorAtStart() = 0;

        virtual bool cursorAtEnd() = 0;

        virtual void moveCursorToEnd() {};

        virtual void moveCursorToStart() {};

        virtual void selectAll() {};

        virtual void clear() = 0;

        inline bool hasFocusableWidget() const { return m_hasFocusableWidget; }

        virtual void showFocus( const TQRect& r, bool readOnly );

        virtual void hideFocus();

        virtual void clickedOnContents();

        bool acceptEditorAfterDeleteContents() const { return m_acceptEditorAfterDeleteContents; }
 
        inline virtual void setFocus() { if (widget()) widget()->setFocus(); }
 
        bool cursorAtNewRow();

        void setParentDataItemInterface(KexiDataItemInterface* parentDataItemInterface);

        inline KexiDataItemInterface* parentInterface() const { return m_parentDataItemInterface; }

        virtual void handleAction(const TQString& actionName) { Q_UNUSED(actionName); }
 
    protected:
        virtual void setValueInternal(const TQVariant& add, bool removeOld) = 0;

        virtual void setVisibleValueInternal(const TQVariant& value);
 
//      //! Sets value \a value for a widget. 
//      //! Implement this method to allow setting value for this widget item.
//      virtual void setValueInternal(const TQVariant& value) = 0;

        virtual void signalValueChanged();

        virtual void beforeSignalValueChanged() {};
 
        KexiDataItemChangesListener* listener();
 
//moved to KexiFormDataItemInterface: TQString m_dataSource;
        TQGuardedPtr<TQObject> m_listenerObject;
        KexiDataItemChangesListener* m_listener;
        bool m_listenerIsTQObject;
        TQVariant m_origValue;

        KexiDataItemInterface* m_parentDataItemInterface;
        bool m_hasFocusableWidget : 1;
        bool m_disable_signalValueChanged : 1;
        bool m_acceptEditorAfterDeleteContents : 1;
};
 
#endif