/****************************************************************************** $Id: qt/src/widgets/qpushbutton.cpp   2.3.12   edited 2005-10-27 $**** Implementation of QPushButton class**** Created : 940221**** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.**** This file is part of the widgets module of the Qt GUI Toolkit.**** This file may be distributed under the terms of the Q Public License** 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.**** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition** licenses may use this file in accordance with the Qt Commercial License** Agreement provided with the Software.**** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.**** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for**   information about Qt Commercial License Agreements.** See http://www.trolltech.com/qpl/ for QPL licensing information.** See http://www.trolltech.com/gpl/ for GPL licensing information.**** Contact info@trolltech.com if any conditions of this licensing are** not clear to you.************************************************************************/#include "qpushbutton.h"#ifndef QT_NO_PUSHBUTTON#include "qdialog.h"#include "qfontmetrics.h"#include "qpainter.h"#include "qdrawutil.h"#include "qpixmap.h"#include "qbitmap.h"#include "qpopupmenu.h"#include "qguardedptr.h"#include "qptrdict.h" // binary compatibility#include "qapplication.h"#include "qtoolbar.h"// NOT REVISED/*!  \class QPushButton qpushbutton.h  \brief The QPushButton widget provides a command button.  \ingroup basic  The push button, also referred to as command button, is perhaps the  most central widget in any graphical user interface: Push it to  command the computer to perform some action. Typical actions are Ok,  Apply, Cancel, Close or Help.  A command button is rectangular (ca. 80x22 pixel) and typically  displays a text label describing its action. An underscored  character in the label, marked with an ampersand in the text,  signals an accelerator key.  This code creates a push button labelled "Rock & Roll".  Due to the  first ampersand, the c displays underscored and the button gets the  automatic accelerator key, Alt-C:  \code    QPushButton *p = new QPushButton( "Ro&ck && Roll", this );  \endcode  The text can be changed anytime later with setText(). You can also  define a pixmap with setPixmap(). The text/pixmap is manipulated as  necessary to create "disabled" appearance according to the  respective GUI style when the button is disabled. A command button  can, in addition to the text or pixmap label, also display a little  icon. Use the extended constructor or setIconSet() to define this  icon.  A push button emits the signal clicked() when it is activated,  either with the mouse, the spacebar or a keyboard accelerator.  Connect to this signal to perform the button's action.  Other  signals of less importance are pressed() when the button is pressed  down and released() when it is released, respectively.  Command buttons in dialogs are by default auto-default buttons,  i.e. they become the default push button automatically when they  receive the keyboard input focus. A default button is a command  button that is activated when the users hits the Enter or Return key  in a dialog. Adjust this behaviour with setAutoDefault(). Note that  auto-default buttons reserve a little extra space necessary to draw  a default-button indicator. If you do not want this space around  your buttons, call setAutoDefault( FALSE ).  Being so central, the widget has grown to accomodate a great many  variations in the past decade, and by now the Microsoft style guide  shows about ten different states of Windows push buttons, and the  text implies that there are dozens more when all the combinations of  features are taken into consideration.  The most important modes or states are, sorted roughly by importance: <ul>  <li> Available or not ("grayed out", disabled).  <li> Standard push button, toggling push button or menu button.  <li> On or off (only for toggling push buttons).  <li> Default or normal.  The default button in a dialog can  generally be "clicked" using the Enter or Return key.  <li> Auto-repeat or not.  <li> Pressed down or not.  </ul>  As a general rule, use a push button when the application or dialog  window performs an action when the user clicks on it (like Apply,  Cancel, Close, Help, ...) \e and when the widget is supposed to have  a wide, rectangular shape with a text label.  Small, typically  square buttons that change the state of the window rather than  performing an action (like for example the buttons in the top/right  corner of the QFileDialog), are not command buttons, but tool  buttons. Qt provides a special class QToolButton for these.  Also, if you need toggle behaviour (see setToggleButton()) or a button  that auto-repeats the activation signal when being pushed down like  the arrows in a scrollbar (see setAutoRepeat()), a command button is  probably not what you want. In case of doubt, go with a tool button.  A variation of a command button is a menu button. It provides not  just one command, but several. Use the method setPopup() to  associate a popup menu with a push button.  Other classes of buttons are option buttons (see QRadioButton) and  check boxes (see QCheckBox).  <img src="qpushbt-m.png"> <img src="qpushbt-w.png">  In Qt, the QButton class provides most of the modes and other API,  and QPushButton provides GUI logic.  See QButton for more  information about the API.  \important text, setText, text, pixmap, setPixmap, accel, setAccel,  isToggleButton, setDown, isDown, isOn, state, autoRepeat,  isExclusiveToggle, group, setAutoRepeat, toggle, pressed, released,  clicked, toggled, state stateChanged  \sa QToolButton, QRadioButton QCheckBox  <a href="guibooks.html#fowler">GUI Design Handbook: Push Button</a>*/class QPushButtonPrivate{public:    QPushButtonPrivate()	:iconset( 0 )    {}    ~QPushButtonPrivate()    {	delete iconset;    }    QGuardedPtr<QPopupMenu> popup;    QIconSet* iconset;};static QPtrDict<QPushButtonPrivate> *d_ptr = 0;static void cleanup_d_ptr(){    delete d_ptr;    d_ptr = 0;}static QPushButtonPrivate* d( const QPushButton* foo ){    if ( !d_ptr ) {	d_ptr = new QPtrDict<QPushButtonPrivate>;	d_ptr->setAutoDelete( TRUE );	qAddPostRoutine( cleanup_d_ptr );    }    QPushButtonPrivate* ret = d_ptr->find( (void*)foo );    if ( ! ret ) {	ret = new QPushButtonPrivate;	d_ptr->replace( (void*) foo, ret );    }    return ret;}static bool has_d( const QPushButton* foo ){    return d_ptr && d_ptr->find( (void*)foo );}static void delete_d( const QPushButton* foo ){    if ( d_ptr )	d_ptr->remove( (void*) foo );}/*!  Constructs a push button with no text.  The \a parent and \a name arguments are sent to the QWidget constructor.*/QPushButton::QPushButton( QWidget *parent, const char *name )	: QButton( parent, name ){    init();}/*!  Constructs a push button with a text.  The \a parent and \a name arguments are sent to the QWidget constructor.*/QPushButton::QPushButton( const QString &text, QWidget *parent,			  const char *name )	: QButton( parent, name ){    init();    setText( text );}/*!  Constructs a push button with an \a icon and a \a text.  Note that you can also pass a QPixmap object as icon (thanks to C++'  implicit type conversion).  The \a parent and \a name arguments are sent to the QWidget constructor.*/QPushButton::QPushButton( const QIconSet& icon, const QString &text,			  QWidget *parent, const char *name )	: QButton( parent, name ){    init();    setText( text );    setIconSet( icon );}/*!  Destructs the push button */QPushButton::~QPushButton(){    delete_d( this );}void QPushButton::init(){    defButton = FALSE;    lastEnabled = FALSE;    hasMenuArrow = FALSE;    flt = FALSE;#ifndef QT_NO_DIALOG    autoDefButton = topLevelWidget()->inherits("QDialog");#else    autoDefButton = FALSE;#endif    setBackgroundMode( PaletteButton );    setSizePolicy( QSizePolicy( QSizePolicy::Minimum, QSizePolicy::Fixed ) );}/*!  Makes the push button a toggle button if \a enable is TRUE, or a normal  push button if \a enable is FALSE.  Toggle buttons have an on/off state similar to \link QCheckBox check  boxes. \endlink A push button is initially not a toggle button.  \sa setOn(), toggle(), isToggleButton() toggled()*/void QPushButton::setToggleButton( bool enable ){    QButton::setToggleButton( enable );}/*!  Switches a toggle button on if \a enable is TRUE or off if \a enable is  FALSE.  \sa isOn(), toggle(), toggled(), isToggleButton()*/void QPushButton::setOn( bool enable ){    if ( !isToggleButton() )	return;    QButton::setOn( enable );}/*!  Toggles the state of a toggle button.  \sa isOn(), setOn(), toggled(), isToggleButton()*/void QPushButton::toggle(){    if ( !isToggleButton() )	return;    QButton::setOn( !isOn() );}/*! \fn bool QPushButton::autoDefault() const  Returns TRUE if the button is an auto-default button.  \sa setAutoDefault()*//*!  Sets the push buttons to an auto-default button if \a enable is TRUE,  or to a normal button if \a enable is FALSE.  An auto-default button becomes automatically the default push button  in a dialog when it receives the keyboard input focus.  In some GUI styles, a default button is drawn with an extra frame  around it, up to 3 pixels or more. Qt automatically keeps this space  free around auto-default buttons, i.e. auto-default buttons may have  a slightly larger size hint.  \sa autoDefault(), setDefault()*/void QPushButton::setAutoDefault( bool enable ){    if ( (bool)autoDefButton == enable )	return;    autoDefButton = enable;    update();    updateGeometry();}/*!  \fn bool QPushButton::isDefault() const  Returns TRUE if the button is currently default.  \sa setDefault()*//*!  Sets this button to be the current default button of a  \link QDialog dialog\endlink if \a enable is TRUE, or to be a normal button  if \a enable is FALSE.  The current default button gets clicked when the user presses the  "Enter" key, independently of which widget in the dialog currently  has the keyboard input focus.  Only one push button can at any time  be the default button.  This button is then displayed with an  additional frame ( depending on the GUI style ).  The default button behaviour is only provided in dialogs. Buttons  can always be clicked from the keyboard by pressing return or the  spacebar when the button has focus.  \sa isDefault(), setAutoDefault(), QDialog*/void QPushButton::setDefault( bool enable ){    if ( (bool)defButton == enable )	return;					// no change    defButton = enable;#ifndef QT_NO_DIALOG    if ( defButton && topLevelWidget()->inherits( "QDialog" ) ) 	((QDialog*)topLevelWidget())->setDefault( this );#endif    update();}/*!\reimp*/QSize QPushButton::sizeHint() const{    constPolish();    int w = 0;    int h = 0;    if ( pixmap() ) {	QPixmap *pm = (QPixmap *)pixmap();	w = pm->width() + style().buttonMargin();