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QComboBox(3qt)									   QComboBox(3qt)

NAME
       QComboBox - Combined button and popup list

SYNOPSIS
       #include <qcombobox.h>

       Inherits QWidget.

   Public Members
       QComboBox ( QWidget * parent = 0, const char * name = 0 )
       QComboBox ( bool rw, QWidget * parent = 0, const char * name = 0 )
       ~QComboBox ()
       int count () const
       void insertStringList ( const QStringList & list, int index = -1 )
       void insertStrList ( const QStrList & list, int index = -1 )
       void insertStrList ( const QStrList * list, int index = -1 )
       void insertStrList ( const char ** strings, int numStrings = -1, int index = -1 )
       void insertItem ( const QString & t, int index = -1 )
       void insertItem ( const QPixmap & pixmap, int index = -1 )
       void insertItem ( const QPixmap & pixmap, const QString & text, int index = -1 )
       void removeItem ( int index )
       int currentItem () const
       virtual void setCurrentItem ( int index )
       QString currentText () const
       virtual void setCurrentText ( const QString & )
       QString text ( int index ) const
       const QPixmap * pixmap ( int index ) const
       void changeItem ( const QString & t, int index )
       void changeItem ( const QPixmap & im, int index )
       void changeItem ( const QPixmap & im, const QString & t, int index )
       bool autoResize () const  (obsolete)
       virtual void setAutoResize ( bool )  (obsolete)
       virtual void setPalette ( const QPalette & palette )
       virtual void setFont ( const QFont & font )
       virtual void setSizeLimit ( int )
       int sizeLimit () const
       virtual void setMaxCount ( int )
       int maxCount () const
       enum Policy { NoInsertion, AtTop, AtCurrent, AtBottom, AfterCurrent, BeforeCurrent }
       virtual void setInsertionPolicy ( Policy policy )
       Policy insertionPolicy () const
       virtual void setValidator ( const QValidator * v )
       const QValidator * validator () const
       virtual void setListBox ( QListBox * newListBox )
       QListBox * listBox () const
       virtual void setLineEdit ( QLineEdit * edit )
       QLineEdit * lineEdit () const
       virtual void setAutoCompletion ( bool )
       bool autoCompletion () const
       void setDuplicatesEnabled ( bool enable )
       bool duplicatesEnabled () const
       bool editable () const
       void setEditable ( bool )
       virtual void popup ()

   Public Slots
       void clear ()
       void clearValidator ()
       void clearEdit ()
       virtual void setEditText ( const QString & newText )

   Signals
       void activated ( int index )
       void highlighted ( int index )
       void activated ( const QString & string )
       void highlighted ( const QString & string )
       void textChanged ( const QString & string )

   Properties
       bool autoCompletion - whether auto-completion is enabled
       bool autoMask - whether the combobox is automatically masked  (read only)
       bool autoResize - whether auto resize is enabled  (obsolete)
       int count - the number of items in the combobox	(read only)
       int currentItem - the index of the current item in the combobox
       QString currentText - the text of the combobox's current item
       bool duplicatesEnabled - whether duplicates are allowed
       bool editable - whether the combobox is editable
       Policy insertionPolicy - the position of the items inserted by the user
       int maxCount - the maximum number of items allowed in the combobox
       int sizeLimit - the maximum on-screen size of the combobox

DESCRIPTION
       The QComboBox widget is a combined button and popup list.

       A combobox is a selection widget which displays the current item and can pop up a list of
       items. A combobox may be editable in which case the user can enter arbitrary strings.

       Comboboxes provide a means of showing the user's current choice out of a list of options
       in a way that takes up the minimum amount of screen space.

       QComboBox supports three different display styles: Aqua/Motif 1.x, Motif 2.0 and Windows.
       In Motif 1.x, a combobox was called XmOptionMenu. In Motif 2.0, OSF introduced an improved
       combobox and named that XmComboBox. QComboBox provides both.

       QComboBox provides two different constructors. The simplest constructor creates an "old-
       style" combobox in Motif (or Aqua) style:

	       QComboBox *c = new QComboBox( this, "read-only combobox" );

       The other constructor creates a new-style combobox in Motif style, and can create both
       read-only and editable comboboxes:

	       QComboBox *c1 = new QComboBox( FALSE, this, "read-only combobox" );
	       QComboBox *c2 = new QComboBox( TRUE, this, "editable combobox" );

       New-style comboboxes use a list box in both Motif and Windows styles, and both the content
       size and the on-screen size of the list box can be limited with sizeLimit() and
       setMaxCount() respectively. Old-style comboboxes use a popup in Aqua and Motif style, and
       that popup will happily grow larger than the desktop if you put enough data into it.

       The two constructors create identical-looking comboboxes in Windows style.

       Comboboxes can contain pixmaps as well as strings; the insertItem() and changeItem()
       functions are suitably overloaded. For editable comboboxes, the function clearEdit() is
       provided, to clear the displayed string without changing the combobox's contents.

       A combobox emits two signals, activated() and highlighted(), when a new item has been
       activated (selected) or highlighted (made current). Both signals exist in two versions,
       one with a QString argument and one with an int argument. If the user highlights or
       activates a pixmap, only the int signals are emitted. Whenever the text of an editable
       combobox is changed the textChanged() signal is emitted.

       When the user enters a new string in an editable combobox, the widget may or may not
       insert it, and it can insert it in several locations. The default policy is is AtBottom
       but you can change this using setInsertionPolicy().

       It is possible to constrain the input to an editable combobox using QValidator; see
       setValidator(). By default, any input is accepted.

       If the combobox is not editable then it has a default focusPolicy() of TabFocus, i.e. it
       will not grab focus if clicked. This differs from both Windows and Motif. If the combobox
       is editable then it has a default focusPolicy() of StrongFocus, i.e. it will grab focus if
       clicked.

       A combobox can be populated using the insert functions, insertStringList() and
       insertItem() for example. Items can be changed with changeItem(). An item can be removed
       with removeItem() and all items can be removed with clear(). The text of the current item
       is returned by currentText(), and the text of a numbered item is returned with text(). The
       current item can be set with setCurrentItem() or setCurrentText(). The number of items in
       the combobox is returned by count(); the maximum number of items can be set with
       setMaxCount(). You can allow editing using setEditable(). For editable comboboxes you can
       set auto-completion using setAutoCompletion() and whether or not the user can add
       duplicates is set with setDuplicatesEnabled().

					    [Image Omitted]

       (Motif 1, read-only)
					    [Image Omitted]

       (Motif 2, editable)
					    [Image Omitted]

       (Motif 2, read-only)
					    [Image Omitted]

       (Windows style)

       Depending on the style, QComboBox will use a QListBox or a QPopupMenu to display the list
       of items. See setListBox() for more information.

       See also QLineEdit, QListBox, QSpinBox, QRadioButton, QButtonGroup, GUI Design Handbook:
       Combo Box, GUI Design Handbook: Drop-Down List Box, and Basic Widgets.

   Member Type Documentation
QComboBox::Policy
       This enum specifies what the QComboBox should do when a new string is entered by the user.

       QComboBox::NoInsertion - the string will not be inserted into the combobox.

       QComboBox::AtTop - insert the string as the first item in the combobox.

       QComboBox::AtCurrent - replace the previously selected item with the string the user has
       entered.

       QComboBox::AtBottom - insert the string as the last item in the combobox.

       QComboBox::AfterCurrent - insert the string after the previously selected item.

       QComboBox::BeforeCurrent - insert the string before the previously selected item.

       activated() is always emitted when the string is entered.

       If inserting the new string would cause the combobox to breach its content size limit, the
       item at the other end of the list is deleted. The definition of "other end" is
       implementation-dependent.

MEMBER FUNCTION DOCUMENTATION
QComboBox::QComboBox ( QWidget * parent = 0, const char * name = 0 )
       Constructs a combobox widget with parent parent called name.

       This constructor creates a popup list if the program uses Motif (or Aqua) look and feel;
       this is compatible with Motif 1.x and Aqua.

       Note: If you use this constructor to create your QComboBox, then the pixmap() function
       will always return 0. To workaround this, use the other constructor.

QComboBox::QComboBox ( bool rw, QWidget * parent = 0, const char * name = 0 )
       Constructs a combobox with a maximum size and either Motif 2.0 or Windows look and feel.

       The input field can be edited if rw is TRUE, otherwise the user may only choose one of the
       items in the combobox.

       The parent and name arguments are passed on to the QWidget constructor.

QComboBox::~QComboBox ()
       Destroys the combobox.

void QComboBox::activated ( int index ) [signal]
       This signal is emitted when a new item has been activated (selected). The index is the
       position of the item in the combobox.

       This signal is not emitted if the item is changed programmatically, e.g. using
       setCurrentItem().

       Examples:

void QComboBox::activated ( const QString & string ) [signal]
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       This signal is emitted when a new item has been activated (selected). string is the
       selected string.

       You can also use the activated(int) signal, but be aware that its argument is meaningful
       only for selected strings, not for user entered strings.

bool QComboBox::autoCompletion () const
       Returns TRUE if auto-completion is enabled; otherwise returns FALSE. See the
       "autoCompletion" property for details.

bool QComboBox::autoResize () const
       Returns TRUE if auto resize is enabled; otherwise returns FALSE. See the "autoResize"
       property for details.

void QComboBox::changeItem ( const QString & t, int index )
       Replaces the item at position index with the text t.

void QComboBox::changeItem ( const QPixmap & im, int index )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Replaces the item at position index with the pixmap im, unless the combobox is editable.

       See also insertItem().

void QComboBox::changeItem ( const QPixmap & im, const QString & t, int index )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Replaces the item at position index with the pixmap im and the text t.

       See also insertItem().

void QComboBox::clear () [slot]
       Removes all combobox items.

void QComboBox::clearEdit () [slot]
       Clears the line edit without changing the combobox's contents. Does nothing if the
       combobox isn't editable.

       This is particularly useful when using a combobox as a line edit with history. For example
       you can connect the combobox's activated() signal to clearEdit() in order to present the
       user with a new, empty line as soon as Enter is pressed.

       See also setEditText().

void QComboBox::clearValidator () [slot]
       This slot is equivalent to setValidator( 0 ).

int QComboBox::count () const
       Returns the number of items in the combobox. See the "count" property for details.

int QComboBox::currentItem () const
       Returns the index of the current item in the combobox. See the "currentItem" property for
       details.

QString QComboBox::currentText () const
       Returns the text of the combobox's current item. See the "currentText" property for
       details.

bool QComboBox::duplicatesEnabled () const
       Returns TRUE if duplicates are allowed; otherwise returns FALSE. See the
       "duplicatesEnabled" property for details.

bool QComboBox::editable () const
       Returns TRUE if the combobox is editable; otherwise returns FALSE. See the "editable"
       property for details.

void QComboBox::highlighted ( int index ) [signal]
       This signal is emitted when a new item has been set to be the current item. The index is
       the position of the item in the combobox.

       This signal is not emitted if the item is changed programmatically, e.g. using
       setCurrentItem().

void QComboBox::highlighted ( const QString & string ) [signal]
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       This signal is emitted when a new item has been set to be the current item. string is the
       item's text.

       You can also use the highlighted(int) signal.

void QComboBox::insertItem ( const QString & t, int index = -1 )
       Inserts a text item with text t, at position index. The item will be appended if index is
       negative.

       Examples:

void QComboBox::insertItem ( const QPixmap & pixmap, int index = -1 )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Inserts a pixmap item at position index. The item will be appended if index is negative.

void QComboBox::insertItem ( const QPixmap & pixmap, const QString & text, int index = -1 )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Inserts a pixmap item with additional text text at position index. The item will be
       appended if index is negative.

void QComboBox::insertStrList ( const char ** strings, int numStrings = -1, int index = -1 )
       Inserts the array of char * strings at position index in the combobox.

       The numStrings argument is the number of strings. If numStrings is -1 (default), the
       strings array must be terminated with 0.

       Example:

	       static const char* items[] = { "red", "green", "blue", 0 };
	       combo->insertStrList( items );

       See also insertStringList().

       Example: qmag/qmag.cpp.

void QComboBox::insertStrList ( const QStrList & list, int index = -1 )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Inserts the list of strings at position index in the combobox.

       This is only for compatibility since it does not support Unicode strings. See
       insertStringList().

void QComboBox::insertStrList ( const QStrList * list, int index = -1 )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Inserts the list of strings at position index in the combobox.

       This is only for compatibility since it does not support Unicode strings. See
       insertStringList().

void QComboBox::insertStringList ( const QStringList & list, int index = -1 )
       Inserts the list of strings at position index in the combobox.

Policy QComboBox::insertionPolicy () const
       Returns the position of the items inserted by the user. See the "insertionPolicy" property
       for details.

QLineEdit * QComboBox::lineEdit () const
       Returns the line edit, or 0 if there is no line edit.

       Only editable listboxes have a line editor.

QListBox * QComboBox::listBox () const
       Returns the current list box, or 0 if there is no list box. (QComboBox can use QPopupMenu
       instead of QListBox.) Provided to match setListBox().

       See also setListBox().

       Example: listboxcombo/listboxcombo.cpp.

int QComboBox::maxCount () const
       Returns the maximum number of items allowed in the combobox. See the "maxCount" property
       for details.

const QPixmap * QComboBox::pixmap ( int index ) const
       Returns the pixmap item at position index, or 0 if the item is not a pixmap.

void QComboBox::popup () [virtual]
       Pops up the combobox popup list.

       If the list is empty, no items appear.

void QComboBox::removeItem ( int index )
       Removes the item at position index.

void QComboBox::setAutoCompletion ( bool ) [virtual]
       Sets whether auto-completion is enabled. See the "autoCompletion" property for details.

void QComboBox::setAutoResize ( bool ) [virtual]
       Sets whether auto resize is enabled. See the "autoResize" property for details.

void QComboBox::setCurrentItem ( int index ) [virtual]
       Sets the index of the current item in the combobox to index. See the "currentItem"
       property for details.

void QComboBox::setCurrentText ( const QString & ) [virtual]
       Sets the text of the combobox's current item. See the "currentText" property for details.

void QComboBox::setDuplicatesEnabled ( bool enable )
       Sets whether duplicates are allowed to enable. See the "duplicatesEnabled" property for
       details.

void QComboBox::setEditText ( const QString & newText ) [virtual slot]
       Sets the text in the line edit to newText without changing the combobox's contents. Does
       nothing if the combobox isn't editable.

       This is useful e.g. for providing a good starting point for the user's editing and
       entering the change in the combobox only when the user presses Enter.

       See also clearEdit() and insertItem().

void QComboBox::setEditable ( bool )
       Sets whether the combobox is editable. See the "editable" property for details.

void QComboBox::setFont ( const QFont & font ) [virtual]
       Sets the font for both the combobox button and the combobox popup list to font.

       Reimplemented from QWidget.

void QComboBox::setInsertionPolicy ( Policy policy ) [virtual]
       Sets the position of the items inserted by the user to policy. See the "insertionPolicy"
       property for details.

void QComboBox::setLineEdit ( QLineEdit * edit ) [virtual]
       Sets the line edit to use edit instead of the current line edit.

void QComboBox::setListBox ( QListBox * newListBox ) [virtual]
       Sets the combobox to use newListBox instead of the current list box or popup. As a side
       effect, it clears the combobox of its current contents.

       Warning: QComboBox assumes that newListBox->text(n) returns non-null for 0 <= n <
       newListbox->count(). This assumption is necessary because of the line edit in QComboBox.

void QComboBox::setMaxCount ( int ) [virtual]
       Sets the maximum number of items allowed in the combobox. See the "maxCount" property for
       details.

void QComboBox::setPalette ( const QPalette & palette ) [virtual]
       Sets the palette for both the combobox button and the combobox popup list to palette.

       Reimplemented from QWidget.

void QComboBox::setSizeLimit ( int ) [virtual]
       Sets the maximum on-screen size of the combobox. See the "sizeLimit" property for details.

void QComboBox::setValidator ( const QValidator * v ) [virtual]
       Applies the validator v to the combobox so that only text which is valid according to v is
       accepted.

       This function does nothing if the combobox is not editable.

       See also validator(), clearValidator(), and QValidator.

int QComboBox::sizeLimit () const
       Returns the maximum on-screen size of the combobox. See the "sizeLimit" property for
       details.

QString QComboBox::text ( int index ) const
       Returns the text item at position index, or QString::null if the item is not a string.

       See also currentText.

       Examples:

void QComboBox::textChanged ( const QString & string ) [signal]
       This signal is used for editable comboboxes. It is emitted whenever the contents of the
       text entry field changes. string contains the new text.

const QValidator * QComboBox::validator () const
       Returns the validator which constrains editing for this combobox if there is one;
       otherwise returns 0.

       See also setValidator(), clearValidator(), and QValidator.

   Property Documentation
bool autoCompletion
       This property holds whether auto-completion is enabled.

       This property can only be set for editable comboboxes, for non-editable comboboxes it has
       no effect. It is FALSE by default.

       Set this property's value with setAutoCompletion() and get this property's value with
       autoCompletion().

bool autoMask
       This property holds whether the combobox is automatically masked.

       See also QWidget::autoMask.

bool autoResize
       This property holds whether auto resize is enabled.

       This property is obsolete. It is provided to keep old source working. We strongly advise
       against using it in new code.

       If this property is set to TRUE then the combobox will resize itself whenever its contents
       change. The default is FALSE.

       Set this property's value with setAutoResize() and get this property's value with
       autoResize().

int count
       This property holds the number of items in the combobox.

       Get this property's value with count().

int currentItem
       This property holds the index of the current item in the combobox.

       Note that the activated() and highlighted() signals are only emitted when the user changes
       the current item, not when it is changed programmatically.

       Set this property's value with setCurrentItem() and get this property's value with
       currentItem().

QString currentText
       This property holds the text of the combobox's current item.

       Set this property's value with setCurrentText() and get this property's value with
       currentText().

bool duplicatesEnabled
       This property holds whether duplicates are allowed.

       If the combobox is editable and the user enters some text in the combobox's lineedit and
       presses Enter (and the insertionPolicy() is not NoInsertion), then what happens is this:

       If the text is not already in the list, the text is inserted.

       If the text is in the list and this property is TRUE (the default), the text is inserted.

       If the text is in the list and this property is FALSE, the text is not inserted; instead
       the item which has matching text becomes the current item.

       This property only affects user-interaction. You can use insertItem() to insert duplicates
       if you wish regardless of this setting.

       Set this property's value with setDuplicatesEnabled() and get this property's value with
       duplicatesEnabled().

bool editable
       This property holds whether the combobox is editable.

       This property's default is FALSE. Note that the combobox will be cleared if this property
       is set to TRUE for a 1.x Motif style combobox. To avoid this, use setEditable() before
       inserting any items. Also note that the 1.x version of Motif didn't have any editable
       comboboxes, so the combobox will change it's appearance to a 2.0 style Motif combobox is
       it is set to be editable.

       Set this property's value with setEditable() and get this property's value with
       editable().

Policy insertionPolicy
       This property holds the position of the items inserted by the user.

       The default insertion policy is AtBottom. See Policy.

       Set this property's value with setInsertionPolicy() and get this property's value with
       insertionPolicy().

int maxCount
       This property holds the maximum number of items allowed in the combobox.

       Set this property's value with setMaxCount() and get this property's value with
       maxCount().

int sizeLimit
       This property holds the maximum on-screen size of the combobox.

       This property is ignored for both Motif 1.x style and non-editable comboboxes in Mac
       style. The default limit is ten lines. If the number of items in the combobox is or grows
       larger than lines, a scrollbar is added.

       Set this property's value with setSizeLimit() and get this property's value with
       sizeLimit().

SEE ALSO
       http://doc.trolltech.com/qcombobox.html http://www.trolltech.com/faq/tech.html

COPYRIGHT
       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the license file
       included in the distribution for a complete license statement.

AUTHOR
       Generated automatically from the source code.

BUGS
       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is located at
       $QTDIR/doc/html and can be read using Qt Assistant or with a web browser. This man page is
       provided as a convenience for those users who prefer man pages, although this format is
       not officially supported by Trolltech.

       If you find errors in this manual page, please report them to qt-bugs@trolltech.com.
       Please include the name of the manual page (qcombobox.3qt) and the Qt version (3.3.8).

Trolltech AS				 2 February 2007			   QComboBox(3qt)
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