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QProgressDialog(3qt)							     QProgressDialog(3qt)

NAME
       QProgressDialog - Feedback on the progress of a slow operation

SYNOPSIS
       #include <qprogressdialog.h>

       Inherits QDialog.

   Public Members
       QProgressDialog ( QWidget * creator = 0, const char * name = 0, bool modal = FALSE, WFlags
	   f = 0 )
       QProgressDialog ( const QString & labelText, const QString & cancelButtonText, int
	   totalSteps, QWidget * creator = 0, const char * name = 0, bool modal = FALSE, WFlags f
	   = 0 )
       ~QProgressDialog ()
       void setLabel ( QLabel * label )
       void setCancelButton ( QPushButton * cancelButton )
       void setBar ( QProgressBar * bar )
       bool wasCancelled () const  (obsolete)
       bool wasCanceled () const
       int totalSteps () const
       int progress () const
       virtual QSize sizeHint () const
       QString labelText () const
       void setAutoReset ( bool b )
       bool autoReset () const
       void setAutoClose ( bool b )
       bool autoClose () const
       int minimumDuration () const

   Public Slots
       void cancel ()
       void reset ()
       void setTotalSteps ( int totalSteps )
       void setProgress ( int progress )
       void setProgress ( int progress, int totalSteps )
       void setLabelText ( const QString & )
       void setCancelButtonText ( const QString & cancelButtonText )
       void setMinimumDuration ( int ms )

   Signals
       void cancelled ()  (obsolete)
       void canceled ()

   Properties
       bool autoClose - whether the dialog gets hidden by reset()
       bool autoReset - whether the progress dialog calls reset() as soon as progress() equals
	   totalSteps()
       QString labelText - the label's text
       int minimumDuration - the time that must pass before the dialog appears
       int progress - the current amount of progress made
       int totalSteps - the total number of steps
       bool wasCanceled - whether the dialog was canceled  (read only)
       bool wasCancelled - whether the dialog was canceled  (read only)  (obsolete)

   Protected Slots
       void forceShow ()

DESCRIPTION
       The QProgressDialog class provides feedback on the progress of a slow operation.

       A progress dialog is used to give the user an indication of how long an operation is going
       to take, and to demonstrate that the application has not frozen. It can also give the user
       an opportunity to abort the operation.

       A common problem with progress dialogs is that it is difficult to know when to use them;
       operations take different amounts of time on different hardware. QProgressDialog offers a
       solution to this problem: it estimates the time the operation will take (based on time for
       steps), and only shows itself if that estimate is beyond minimumDuration() (4 seconds by
       default).

       Use setTotalSteps() (or the constructor) to set the number of" steps" in the operation and
       call setProgress() as the operation progresses. The step value can be chosen arbitrarily.
       It can be the number of files copied, the number of bytes received, the number of
       iterations through the main loop of your algorithm, or some other suitable unit. Progress
       starts at 0, and the progress dialog shows that the operation has finished when you call
       setProgress() with totalSteps() as its argument.

       The dialog automatically resets and hides itself at the end of the operation. Use
       setAutoReset() and setAutoClose() to change this behavior.

       There are two ways of using QProgressDialog: modal and modeless.

       Using a modal QProgressDialog is simpler for the programmer, but you must call
       QApplication::processEvents() or QEventLoop::processEvents(ExcludeUserInput) to keep the
       event loop running to ensure that the application doesn't freeze. Do the operation in a
       loop, call setProgress() at intervals, and check for cancellation with wasCanceled(). For
       example:

       QProgressDialog progress( "Copying files...", "Abort Copy", numFiles,
				 this, "progress", TRUE );
       for ( int i = 0; i < numFiles; i++ ) {
	   progress.setProgress( i );
	   qApp->processEvents();
	   if ( progress.wasCanceled() )
	       break;
	   //... copy one file
       }
       progress.setProgress( numFiles );

       A modeless progress dialog is suitable for operations that take place in the background,
       where the user is able to interact with the application. Such operations are typically
       based on QTimer (or QObject::timerEvent()), QSocketNotifier, or QUrlOperator; or performed
       in a separate thread. A QProgressBar in the status bar of your main window is often an
       alternative to a modeless progress dialog.

       You need to have an event loop to be running, connect the canceled() signal to a slot that
       stops the operation, and call setProgress() at intervals. For example:

       Operation::Operation( QObject *parent = 0 )
	   : QObject( parent ), steps( 0 )
       {
	   pd = new QProgressDialog( "Operation in progress.", "Cancel", 100 );
	   connect( pd, SIGNAL(canceled()), this, SLOT(cancel()) );
	   t = new QTimer( this );
	   connect( t, SIGNAL(timeout()), this, SLOT(perform()) );
	   t->start( 0 );
       }
       void Operation::perform()
       {
	   pd->setProgress( steps );
	   //... perform one percent of the operation
	   steps++;
	   if ( steps > pd->totalSteps() )
	       t->stop();
       }
       void Operation::cancel()
       {
	   t->stop();
	   //... cleanup
       }

       In both modes the progress dialog may be customized by replacing the child widgets with
       custom widgets by using setLabel(), setBar(), and setCancelButton(). The functions
       setLabelText() and setCancelButtonText() set the texts shown.

					    [Image Omitted]

					    [Image Omitted]

       See also QDialog, QProgressBar, GUI Design Handbook: Progress Indicator, and Dialog
       Classes.

MEMBER FUNCTION DOCUMENTATION
QProgressDialog::QProgressDialog ( QWidget * creator = 0, const char * name = 0, bool modal =
       FALSE, WFlags f = 0 )
       Constructs a progress dialog.

       Default settings:

       The label text is empty.

       The cancel button text is (translated) "Cancel".

       The total number of steps is 100.

       The creator argument is the widget to use as the dialog's parent. The name, modal, and the
       widget flags, f, are passed to the QDialog::QDialog() constructor. If modal is FALSE (the
       default), you must have an event loop proceeding for any redrawing of the dialog to occur.
       If modal is TRUE, the dialog ensures that events are processed when needed.

       See also labelText, setLabel(), setCancelButtonText(), setCancelButton(), and totalSteps.

QProgressDialog::QProgressDialog ( const QString & labelText, const QString & cancelButtonText,
       int totalSteps, QWidget * creator = 0, const char * name = 0, bool modal = FALSE, WFlags f
       = 0 )
       Constructs a progress dialog.

       The labelText is text used to remind the user what is progressing.

       The cancelButtonText is the text to display on the cancel button, or 0 if no cancel button
       is to be shown.

       The totalSteps is the total number of steps in the operation for which this progress
       dialog shows progress. For example, if the operation is to examine 50 files, this value
       would be 50. Before examining the first file, call setProgress(0). As each file is
       processed call setProgress(1), setProgress(2), etc., finally calling setProgress(50) after
       examining the last file.

       The creator argument is the widget to use as the dialog's parent. The name, modal, and
       widget flags, f, are passed to the QDialog::QDialog() constructor. If modal is FALSE (the
       default), you will must have an event loop proceeding for any redrawing of the dialog to
       occur. If modal is TRUE, the dialog ensures that events are processed when needed.

       See also labelText, setLabel(), setCancelButtonText(), setCancelButton(), and totalSteps.

QProgressDialog::~QProgressDialog ()
       Destroys the progress dialog.

bool QProgressDialog::autoClose () const
       Returns TRUE if the dialog gets hidden by reset(); otherwise returns FALSE. See the
       "autoClose" property for details.

bool QProgressDialog::autoReset () const
       Returns TRUE if the progress dialog calls reset() as soon as progress() equals
       totalSteps(); otherwise returns FALSE. See the "autoReset" property for details.

void QProgressDialog::cancel () [slot]
       Resets the progress dialog. wasCanceled() becomes TRUE until the progress dialog is reset.
       The progress dialog becomes hidden.

void QProgressDialog::canceled () [signal]
       This signal is emitted when the cancel button is clicked. It is connected to the cancel()
       slot by default.

       See also wasCanceled.

void QProgressDialog::cancelled () [signal]
       This function is obsolete. It is provided to keep old source working. We strongly advise
       against using it in new code.

       Use canceled() instead.

       Examples:

void QProgressDialog::forceShow () [protected slot]
       Shows the dialog if it is still hidden after the algorithm has been started and
       minimumDuration milliseconds have passed.

       See also minimumDuration.

QString QProgressDialog::labelText () const
       Returns the label's text. See the "labelText" property for details.

int QProgressDialog::minimumDuration () const
       Returns the time that must pass before the dialog appears. See the "minimumDuration"
       property for details.

int QProgressDialog::progress () const
       Returns the current amount of progress made. See the "progress" property for details.

void QProgressDialog::reset () [slot]
       Resets the progress dialog. The progress dialog becomes hidden if autoClose() is TRUE.

       See also autoClose and autoReset.

       Example: network/ftpclient/ftpmainwindow.ui.h.

void QProgressDialog::setAutoClose ( bool b )
       Sets whether the dialog gets hidden by reset() to b. See the "autoClose" property for
       details.

void QProgressDialog::setAutoReset ( bool b )
       Sets whether the progress dialog calls reset() as soon as progress() equals totalSteps()
       to b. See the "autoReset" property for details.

void QProgressDialog::setBar ( QProgressBar * bar )
       Sets the progress bar widget to bar. The progress dialog resizes to fit. The progress
       dialog takes ownership of the progress bar which will be deleted when necessary, so do not
       use a progress bar allocated on the stack.

void QProgressDialog::setCancelButton ( QPushButton * cancelButton )
       Sets the cancel button to the push button, cancelButton. The progress dialog takes
       ownership of this button which will be deleted when necessary, so do not pass the address
       of an object that is on the stack, i.e. use new() to create the button.

       See also setCancelButtonText().

void QProgressDialog::setCancelButtonText ( const QString & cancelButtonText ) [slot]
       Sets the cancel button's text to cancelButtonText.

       See also setCancelButton().

void QProgressDialog::setLabel ( QLabel * label )
       Sets the label to label. The progress dialog resizes to fit. The label becomes owned by
       the progress dialog and will be deleted when necessary, so do not pass the address of an
       object on the stack.

       See also labelText.

       Example: progress/progress.cpp.

void QProgressDialog::setLabelText ( const QString & ) [slot]
       Sets the label's text. See the "labelText" property for details.

void QProgressDialog::setMinimumDuration ( int ms ) [slot]
       Sets the time that must pass before the dialog appears to ms. See the "minimumDuration"
       property for details.

void QProgressDialog::setProgress ( int progress ) [slot]
       Sets the current amount of progress made to progress. See the "progress" property for
       details.

void QProgressDialog::setProgress ( int progress, int totalSteps ) [slot]
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Sets the current amount of progress to progress and the total number of steps to
       totalSteps.

       See also totalSteps.

void QProgressDialog::setTotalSteps ( int totalSteps ) [slot]
       Sets the total number of steps to totalSteps. See the "totalSteps" property for details.

QSize QProgressDialog::sizeHint () const [virtual]
       Returns a size that fits the contents of the progress dialog. The progress dialog resizes
       itself as required, so you should not need to call this yourself.

int QProgressDialog::totalSteps () const
       Returns the total number of steps. See the "totalSteps" property for details.

bool QProgressDialog::wasCanceled () const
       Returns TRUE if the dialog was canceled; otherwise returns FALSE. See the "wasCanceled"
       property for details.

bool QProgressDialog::wasCancelled () const
       Returns TRUE if the dialog was canceled; otherwise returns FALSE. See the "wasCancelled"
       property for details.

   Property Documentation
bool autoClose
       This property holds whether the dialog gets hidden by reset().

       The default is TRUE.

       See also autoReset.

       Set this property's value with setAutoClose() and get this property's value with
       autoClose().

bool autoReset
       This property holds whether the progress dialog calls reset() as soon as progress() equals
       totalSteps().

       The default is TRUE.

       See also autoClose.

       Set this property's value with setAutoReset() and get this property's value with
       autoReset().

QString labelText
       This property holds the label's text.

       The default text is QString::null.

       Set this property's value with setLabelText() and get this property's value with
       labelText().

int minimumDuration
       This property holds the time that must pass before the dialog appears.

       If the expected duration of the task is less than the minimumDuration, the dialog will not
       appear at all. This prevents the dialog popping up for tasks that are quickly over. For
       tasks that are expected to exceed the minimumDuration, the dialog will pop up after the
       minimumDuration time or as soon as any progress is set.

       If set to 0, the dialog is always shown as soon as any progress is set. The default is
       4000 milliseconds.

       Set this property's value with setMinimumDuration() and get this property's value with
       minimumDuration().

int progress
       This property holds the current amount of progress made.

       For the progress dialog to work as expected, you should initially set this property to 0
       and finally set it to QProgressDialog::totalSteps(); you can call setProgress() any number
       of times in-between.

       Warning: If the progress dialog is modal (see QProgressDialog::QProgressDialog()), this
       function calls QApplication::processEvents(), so take care that this does not cause
       undesirable re-entrancy in your code. For example, don't use a QProgressDialog inside a
       paintEvent()!

       See also totalSteps.

       Set this property's value with setProgress() and get this property's value with
       progress().

int totalSteps
       This property holds the total number of steps.

       The default is 0.

       Set this property's value with setTotalSteps() and get this property's value with
       totalSteps().

bool wasCanceled
       This property holds whether the dialog was canceled.

       Get this property's value with wasCanceled().

       See also progress.

bool wasCancelled
       This property holds whether the dialog was canceled.

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

       Use wasCanceled instead.

       Get this property's value with wasCancelled().

SEE ALSO
       http://doc.trolltech.com/qprogressdialog.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 (qprogressdialog.3qt) and the Qt version
       (3.3.8).

Trolltech AS				 2 February 2007		     QProgressDialog(3qt)
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