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This is the verbatim text of the qlayout.h include file. It is provided only for illustration; the copyright remains with Trolltech.

---

/****************************************************************************
** $Id$
**
** Definition of layout classes
**
** Created : 960416
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of the kernel module of the Qt GUI Toolkit.
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** as defined by Trolltech AS of Norway and appearing in the file
** LICENSE.QPL included in the packaging of this file.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
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** licenses may use this file in accordance with the Qt Commercial License
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** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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**   information about Qt Commercial License Agreements.
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#ifndef QLAYOUT_H
#define QLAYOUT_H

#ifndef QT_H
#include "qobject.h"
#include "qsizepolicy.h"
#include "qwidget.h"
#endif // QT_H

#ifndef QT_NO_LAYOUT

#if 0
Q_OBJECT
#endif
//static const int QLAYOUTSIZE_MAX=INT_MAX/256/16; //wait for 3.1

/*
  First comes the definition of QLayout and of related abstract
  classes that used to be defined in qabstractlayout.h.
*/

class QMenuBar;
class QWidget;
struct QLayoutData;
class QLayoutItem;
class QLayout;
class QSpacerItem;

class Q_EXPORT QGLayoutIterator : public QShared
{
public:
    virtual ~QGLayoutIterator();
    virtual QLayoutItem *next() = 0;
    virtual QLayoutItem *current() = 0;
    virtual QLayoutItem *takeCurrent() = 0;
};

class Q_EXPORT QLayoutIterator
{
public:
    QLayoutIterator( QGLayoutIterator *i ) :it( i ) { }
    QLayoutIterator( const QLayoutIterator &i ) :it( i.it )
    { if ( it ) it->ref(); }
    ~QLayoutIterator() { if ( it && it->deref() ) delete it; }
    QLayoutIterator &operator=( const QLayoutIterator &i )
    {
	if ( i.it ) i.it->ref();
	if ( it && it->deref() ) delete it;
	it = i.it;
	return *this;
    }
    QLayoutItem *operator++() { return it ? it->next() : 0; }
    QLayoutItem *current() { return it ? it->current() : 0; }
    QLayoutItem *takeCurrent() { return it ? it->takeCurrent() : 0; }
    void deleteCurrent();

private:
    QGLayoutIterator *it;
};

class Q_EXPORT QLayoutItem
{
public:
    QLayoutItem( int alignment = 0 ) : align( alignment ) { }
    virtual ~QLayoutItem();
    virtual QSize sizeHint() const = 0;
    virtual QSize minimumSize() const = 0;
    virtual QSize maximumSize() const = 0;
    virtual QSizePolicy::ExpandData expanding() const = 0;
    virtual void setGeometry( const QRect& ) = 0;
    virtual QRect geometry() const = 0;
    virtual bool isEmpty() const = 0;
    virtual bool hasHeightForWidth() const;
    virtual int heightForWidth( int ) const;
    virtual void invalidate();

    virtual QWidget *widget();
    virtual QLayoutIterator iterator();
    virtual QLayout *layout();
    virtual QSpacerItem *spacerItem();

    int alignment() const { return align; }
    virtual void setAlignment( int a );

protected:
    int align;
};

class Q_EXPORT QSpacerItem : public QLayoutItem
{
 public:
    QSpacerItem( int w, int h,
		 QSizePolicy::SizeType hData=QSizePolicy::Minimum,
		 QSizePolicy::SizeType vData= QSizePolicy::Minimum )
	: width( w ), height( h ), sizeP( hData, vData ) { }
    void changeSize( int w, int h,
		     QSizePolicy::SizeType hData=QSizePolicy::Minimum,
		     QSizePolicy::SizeType vData=QSizePolicy::Minimum );
    QSize sizeHint() const;
    QSize minimumSize() const;
    QSize maximumSize() const;
    QSizePolicy::ExpandData expanding() const;
    bool isEmpty() const;
    void setGeometry( const QRect& );
    QRect geometry() const;
    QSpacerItem *spacerItem();

private:
    int width;
    int height;
    QSizePolicy sizeP;
    QRect rect;
};

class Q_EXPORT QWidgetItem : public QLayoutItem
{
public:
    QWidgetItem( QWidget *w ) : wid( w ) { }
    QSize sizeHint() const;
    QSize minimumSize() const;
    QSize maximumSize() const;
    QSizePolicy::ExpandData expanding() const;
    bool isEmpty() const;
    void setGeometry( const QRect& );
    QRect geometry() const;
    virtual QWidget *widget();

    bool hasHeightForWidth() const;
    int heightForWidth( int ) const;

private:
    QWidget *wid;
};

class Q_EXPORT QLayout : public QObject, public QLayoutItem
{
    Q_OBJECT
    Q_ENUMS( ResizeMode )
    Q_PROPERTY( int margin READ margin WRITE setMargin )
    Q_PROPERTY( int spacing READ spacing WRITE setSpacing )
    Q_PROPERTY( ResizeMode resizeMode READ resizeMode WRITE setResizeMode )

public:
    QLayout( QWidget *parent, int margin = 0, int spacing = -1,
	     const char *name = 0 );
    QLayout( QLayout *parentLayout, int spacing = -1, const char *name = 0 );
    QLayout( int spacing = -1, const char *name = 0 );

    ~QLayout();

    int margin() const { return outsideBorder; }
    int spacing() const { return insideSpacing; }

    virtual void setMargin( int );
    virtual void setSpacing( int );

    //enum { unlimited = QLAYOUTSIZE_MAX }; //in 3.1
    enum { unlimited = QWIDGETSIZE_MAX };
    int defaultBorder() const { return insideSpacing; }
    void freeze( int w, int h );
    void freeze() { setResizeMode( Fixed ); }

    enum ResizeMode { FreeResize, Minimum, Fixed };
    void setResizeMode( ResizeMode );
    ResizeMode resizeMode() const;

#ifndef QT_NO_MENUBAR
    virtual void  setMenuBar( QMenuBar *w );
    QMenuBar *menuBar() const { return menubar; }
#endif

    QWidget *mainWidget();
    bool isTopLevel() const { return topLevel; }

    virtual void setAutoAdd( bool );
    bool autoAdd() const { return autoNewChild; }

    void invalidate();
    QRect geometry() const;
    bool activate();

    void add( QWidget *w ) { addItem( new QWidgetItem(w) ); }
    virtual void addItem ( QLayoutItem * ) = 0;

    QSizePolicy::ExpandData expanding() const;
    QSize minimumSize() const;
    QSize maximumSize() const;
    void setGeometry( const QRect& )=0;
    QLayoutIterator iterator()=0;
    bool isEmpty() const;

    int totalHeightForWidth( int w ) const;
    QSize totalMinimumSize() const;
    QSize totalMaximumSize() const;
    QSize totalSizeHint() const;
    QLayout *layout();

    bool supportsMargin() const { return marginImpl; }

    void setEnabled( bool );
    bool isEnabled() const;

protected:
    bool eventFilter( QObject *, QEvent * );
    void childEvent( QChildEvent *e );
    void addChildLayout( QLayout *l );
    void deleteAllItems();

    void setSupportsMargin( bool );
    QRect alignmentRect( const QRect& ) const;

private:
    void setWidgetLayout( QWidget *, QLayout * );
    void init();
    int insideSpacing;
    int outsideBorder;
    uint topLevel : 1;
    uint autoMinimum : 1;
    uint autoNewChild : 1;
    uint frozen : 1;
    uint activated : 1;
    uint marginImpl : 1;
    uint enabled : 1;
    QRect rect;
    QLayoutData *extraData;
#ifndef QT_NO_MENUBAR
    QMenuBar *menubar;
#endif
private:	// Disabled copy constructor and operator=
#if defined(Q_DISABLE_COPY)
    QLayout( const QLayout & );
    QLayout &operator=( const QLayout & );
#endif

};

inline void QLayoutIterator::deleteCurrent()
{
    delete takeCurrent();
}

/*
  Follow the Q*Layout classes, that always belonged to qlayout.h.
*/

class QGridLayoutData;
class QGridLayoutBox;

class Q_EXPORT QGridLayout : public QLayout
{
    Q_OBJECT
public:
    QGridLayout( QWidget *parent, int nRows = 1, int nCols = 1, int border = 0,
		 int spacing = -1, const char *name = 0 );
    QGridLayout( int nRows = 1, int nCols = 1, int spacing = -1,
		 const char *name = 0 );
    QGridLayout( QLayout *parentLayout, int nRows = 1, int nCols = 1,
		 int spacing = -1, const char *name = 0 );
    ~QGridLayout();

    QSize sizeHint() const;
    QSize minimumSize() const;
    QSize maximumSize() const;

    virtual void setRowStretch( int row, int stretch );
    virtual void setColStretch( int col, int stretch );
    int rowStretch( int row ) const;
    int colStretch( int col ) const;

    int numRows() const;
    int numCols() const;
    QRect cellGeometry( int row, int col ) const;

    bool hasHeightForWidth() const;
    int heightForWidth( int ) const;

    QSizePolicy::ExpandData expanding() const;
    void invalidate();

    void addItem( QLayoutItem * );
    void addItem( QLayoutItem *item, int row, int col );
    void addMultiCell( QLayoutItem *, int fromRow, int toRow,
			       int fromCol, int toCol, int align = 0 );
    // void setAlignment( QWidget* );

    void addWidget( QWidget *, int row, int col, int align = 0 );
    void addMultiCellWidget( QWidget *, int fromRow, int toRow,
			     int fromCol, int toCol, int align = 0 );
    void addLayout( QLayout *layout, int row, int col);
    void addMultiCellLayout( QLayout *layout, int fromRow, int toRow,
			     int fromCol, int toCol, int align = 0 );
    void addRowSpacing( int row, int minsize );
    void addColSpacing( int col, int minsize );
    void expand( int rows, int cols );

    enum Corner { TopLeft, TopRight, BottomLeft, BottomRight };
    void setOrigin( Corner );
    Corner origin() const;
    QLayoutIterator iterator();
    void setGeometry( const QRect& );

protected:
    bool findWidget( QWidget* w, int *r, int *c );
    void add( QLayoutItem*, int row, int col );

private:	// Disabled copy constructor and operator=
#if defined(Q_DISABLE_COPY)
    QGridLayout( const QGridLayout & );
    QGridLayout &operator=( const QGridLayout & );
#endif

    void init( int rows, int cols );
    QGridLayoutData *data;
};

class QBoxLayoutData;
class QDockWindow;

class Q_EXPORT QBoxLayout : public QLayout
{
    Q_OBJECT
public:
    enum Direction { LeftToRight, RightToLeft, TopToBottom, BottomToTop,
		     Down = TopToBottom, Up = BottomToTop };

    QBoxLayout( QWidget *parent, Direction, int,
		int spacing = -1, const char *name=0 );
    QBoxLayout( QLayout *parentLayout, Direction, int spacing = -1,
		const char *name=0 );
    QBoxLayout(	Direction, int spacing = -1,
		const char *name=0 );
    ~QBoxLayout();

    void addItem( QLayoutItem * );

    Direction direction() const { return dir; }
    void setDirection( Direction );

    void addSpacing( int size );
    void addStretch( int stretch = 0 );
    void addWidget( QWidget *, int stretch = 0, int alignment = 0 );
    void addLayout( QLayout *layout, int stretch = 0 );
    void addStrut( int );

    void insertSpacing( int index, int size );
    void insertStretch( int index, int stretch = 0 );
    void insertWidget( int index, QWidget *widget, int stretch = 0,
		       int alignment = 0 );
    void insertLayout( int index, QLayout *layout, int stretch = 0 );

    bool setStretchFactor( QWidget*, int stretch );
    bool setStretchFactor( QLayout *l, int stretch );

    QSize sizeHint() const;
    QSize minimumSize() const;
    QSize maximumSize() const;

    bool hasHeightForWidth() const;
    int heightForWidth( int ) const;

    QSizePolicy::ExpandData expanding() const;
    void invalidate();
    QLayoutIterator iterator();
    void setGeometry( const QRect& );

    int findWidget( QWidget* w );

protected:
    void insertItem( int index, QLayoutItem * );

private:	// Disabled copy constructor and operator=
    friend class QDockWindow;
#if defined(Q_DISABLE_COPY)
    QBoxLayout( const QBoxLayout & );
    QBoxLayout &operator=( const QBoxLayout & );
#endif

    void setupGeom();
    int calcHfw( int );
    QBoxLayoutData *data;
    Direction dir;
    QBoxLayout *createTmpCopy();
};

class Q_EXPORT QHBoxLayout : public QBoxLayout
{
    Q_OBJECT
public:
    QHBoxLayout( QWidget *parent, int border = 0,
		 int spacing = -1, const char *name = 0 );
    QHBoxLayout( QLayout *parentLayout,
		 int spacing = -1, const char *name = 0 );
    QHBoxLayout( int spacing = -1, const char *name = 0 );

    ~QHBoxLayout();
};

class Q_EXPORT QVBoxLayout : public QBoxLayout
{
    Q_OBJECT
public:
    QVBoxLayout( QWidget *parent, int border = 0,
		 int spacing = -1, const char *name = 0 );
    QVBoxLayout( QLayout *parentLayout,
		 int spacing = -1, const char *name = 0 );
    QVBoxLayout( int spacing = -1, const char *name = 0 );

    ~QVBoxLayout();
};

#endif // QT_NO_LAYOUT
#endif // QLAYOUT_H