CopperSpice API  1.7.2
QProgressDialog Class Reference

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

Inheritance diagram for QProgressDialog:
QDialog QWidget QObject QPaintDevice

Public Signals

void canceled ()
 
- Public Signals inherited from QDialog
void accepted ()
 
void finished (int result)
 
void rejected ()
 
- Public Signals inherited from QWidget
void customContextMenuRequested (const QPoint &pos)
 
void windowIconChanged (const QIcon &icon)
 
void windowIconTextChanged (const QString &iconText)
 
void windowTitleChanged (const QString &title)
 
- Public Signals inherited from QObject
void destroyed (QObject *obj=nullptr)
 
void objectNameChanged (const QString &objectName)
 

Public Slots

void cancel ()
 
virtual void open ()
 
void reset ()
 
void setCancelButtonText (const QString &text)
 
void setLabelText (const QString &text)
 
void setMaximum (int maximum)
 
void setMinimum (int minimum)
 
void setMinimumDuration (int ms)
 
void setRange (int minimum, int maximum)
 
void setValue (int progress)
 
- Public Slots inherited from QDialog
virtual void accept ()
 
virtual void done (int result)
 
virtual int exec ()
 
virtual void open ()
 
virtual void reject ()
 
void showExtension (bool showExt)
 
- Public Slots inherited from QWidget
bool close ()
 
void hide ()
 
void lower ()
 
void raise ()
 
void repaint ()
 
void setDisabled (bool disable)
 
void setEnabled (bool enable)
 
void setFocus ()
 
void setHidden (bool hidden)
 
void setStyleSheet (const QString &styleSheet)
 
virtual void setVisible (bool visible)
 
void setWindowModified (bool modified)
 
void setWindowTitle (const QString &title)
 
void show ()
 
void showFullScreen ()
 
void showMaximized ()
 
void showMinimized ()
 
void showNormal ()
 
void update ()
 
- Public Slots inherited from QObject
void deleteLater ()
 

Public Methods

 QProgressDialog (const QString &labelText, const QString &cancelButtonText, int minimum, int maximum, QWidget *parent=nullptr, Qt::WindowFlags flags=Qt::EmptyFlag)
 
 QProgressDialog (QWidget *parent=nullptr, Qt::WindowFlags flags=Qt::EmptyFlag)
 
 ~QProgressDialog ()
 
bool autoClose () const
 
bool autoReset () const
 
QString labelText () const
 
int maximum () const
 
int minimum () const
 
int minimumDuration () const
 
void open (QObject *receiver, const QString &member)
 
void setAutoClose (bool close)
 
void setAutoReset (bool reset)
 
void setBar (QProgressBar *bar)
 
void setCancelButton (QPushButton *button)
 
void setCancelButtonCentered (bool value=true)
 
void setLabel (QLabel *label)
 
QSize sizeHint () const override
 
int value () const
 
bool wasCanceled () const
 
- Public Methods inherited from QDialog
 QDialog (QWidget *parent=nullptr, Qt::WindowFlags flags=Qt::EmptyFlag)
 
 ~QDialog ()
 
QWidgetextension () const
 
bool isSizeGripEnabled () const
 
QSize minimumSizeHint () const override
 
Qt::Orientation orientation () const
 
int result () const
 
void setExtension (QWidget *extension)
 
void setModal (bool modal)
 
void setOrientation (Qt::Orientation orientation)
 
void setResult (int result)
 
void setSizeGripEnabled (bool)
 
void setVisible (bool visible) override
 
- Public Methods inherited from QWidget
 QWidget (QWidget *parent=nullptr, Qt::WindowFlags flags=Qt::EmptyFlag)
 
 ~QWidget ()
 
bool acceptDrops () const
 
QString accessibleDescription () const
 
QString accessibleName () const
 
QList< QAction * > actions () const
 
void activateWindow ()
 
void addAction (QAction *action)
 
void addActions (const QList< QAction * > &actions)
 
void adjustSize ()
 
bool autoFillBackground () const
 
QPalette::ColorRole backgroundRole () const
 
QBackingStorebackingStore () const
 
QSize baseSize () const
 
QWidget * childAt (const QPoint &position) const
 
QWidget * childAt (int x, int y) const
 
QRect childrenRect () const
 
QRegion childrenRegion () const
 
void clearFocus ()
 
void clearMask ()
 
QMargins contentsMargins () const
 
QRect contentsRect () const
 
Qt::ContextMenuPolicy contextMenuPolicy () const
 
QCursor cursor () const
 
WId effectiveWinId () const
 
void ensurePolished () const
 
Qt::FocusPolicy focusPolicy () const
 
QWidget * focusProxy () const
 
QWidget * focusWidget () const
 
const QFontfont () const
 
QFontInfo fontInfo () const
 
QFontMetrics fontMetrics () const
 
QPalette::ColorRole foregroundRole () const
 
QRect frameGeometry () const
 
QSize frameSize () const
 
const QRectgeometry () const
 
void getContentsMargins (int *left, int *top, int *right, int *bottom) const
 
QPixmap grab (const QRect &rectangle=QRect (QPoint (0, 0), QSize (-1,-1)))
 
void grabGesture (Qt::GestureType gestureType, Qt::GestureFlags flags=Qt::GestureFlags ())
 
void grabKeyboard ()
 
void grabMouse ()
 
void grabMouse (const QCursor &cursor)
 
int grabShortcut (const QKeySequence &key, Qt::ShortcutContext context=Qt::WindowShortcut)
 
QGraphicsEffectgraphicsEffect () const
 
QGraphicsProxyWidgetgraphicsProxyWidget () const
 
bool hasEditFocus () const
 
bool hasFocus () const
 
virtual bool hasHeightForWidth () const
 
bool hasMouseTracking () const
 
int height () const
 
virtual int heightForWidth (int width) const
 
Qt::InputMethodHints inputMethodHints () const
 
virtual QVariant inputMethodQuery (Qt::InputMethodQuery query) const
 
void insertAction (QAction *before, QAction *action)
 
void insertActions (QAction *before, QList< QAction * > actions)
 
bool isActiveWindow () const
 
bool isAncestorOf (const QWidget *child) const
 
bool isEnabled () const
 
bool isEnabledTo (const QWidget *parent) const
 
bool isEnabledToTLW () const
 
bool isFullScreen () const
 
bool isHidden () const
 
bool isMaximized () const
 
bool isMinimized () const
 
bool isModal () const
 
bool isTopLevel () const
 
bool isVisible () const
 
bool isVisibleTo (const QWidget *parent) const
 
bool isWindow () const
 
bool isWindowModified () const
 
QLayoutlayout () const
 
Qt::LayoutDirection layoutDirection () const
 
QLocale locale () const
 
QPoint mapFrom (const QWidget *parent, const QPoint &pos) const
 
QPoint mapFromGlobal (const QPoint &pos) const
 
QPoint mapFromParent (const QPoint &pos) const
 
QPoint mapTo (const QWidget *parent, const QPoint &pos) const
 
QPoint mapToGlobal (const QPoint &pos) const
 
QPoint mapToParent (const QPoint &pos) const
 
QRegion mask () const
 
int maximumHeight () const
 
QSize maximumSize () const
 
int maximumWidth () const
 
int minimumHeight () const
 
QSize minimumSize () const
 
int minimumWidth () const
 
void move (const QPoint &point)
 
void move (int x, int y)
 
QWidget * nativeParentWidget () const
 
QWidget * nextInFocusChain () const
 
QRect normalGeometry () const
 
void overrideWindowFlags (Qt::WindowFlags flags)
 
QPaintEnginepaintEngine () const override
 
const QPalettepalette () const
 
QWidget * parentWidget () const
 
QPoint pos () const
 
QWidget * previousInFocusChain () const
 
QRect rect () const
 
void releaseKeyboard ()
 
void releaseMouse ()
 
void releaseShortcut (int id)
 
void removeAction (QAction *action)
 
void render (QPaintDevice *target, const QPoint &targetOffset=QPoint (), const QRegion &sourceRegion=QRegion (), RenderFlags renderFlags=RenderFlags (DrawWindowBackground|DrawChildren))
 
void render (QPainter *painter, const QPoint &targetOffset=QPoint (), const QRegion &sourceRegion=QRegion (), RenderFlags renderFlags=RenderFlags (DrawWindowBackground|DrawChildren))
 
void repaint (const QRect &rect)
 
void repaint (const QRegion &region)
 
void repaint (int x, int y, int w, int h)
 
void resize (const QSize &size)
 
void resize (int w, int h)
 
bool restoreGeometry (const QByteArray &geometry)
 
QByteArray saveGeometry () const
 
void scroll (int dx, int dy)
 
void scroll (int dx, int dy, const QRect &rect)
 
void setAcceptDrops (bool on)
 
void setAccessibleDescription (const QString &description)
 
void setAccessibleName (const QString &name)
 
void setAttribute (Qt::WidgetAttribute attribute, bool enable=true)
 
void setAutoFillBackground (bool enable)
 
void setBackgroundRole (QPalette::ColorRole role)
 
void setBaseSize (const QSize &size)
 
void setBaseSize (int basew, int baseh)
 
void setContentsMargins (const QMargins &margins)
 
void setContentsMargins (int left, int top, int right, int bottom)
 
void setContextMenuPolicy (Qt::ContextMenuPolicy policy)
 
void setCursor (const QCursor &cursor)
 
void setEditFocus (bool enable)
 
void setFixedHeight (int h)
 
void setFixedSize (const QSize &size)
 
void setFixedSize (int w, int h)
 
void setFixedWidth (int w)
 
void setFocus (Qt::FocusReason reason)
 
void setFocusPolicy (Qt::FocusPolicy policy)
 
void setFocusProxy (QWidget *widget)
 
void setFont (const QFont &font)
 
void setForegroundRole (QPalette::ColorRole role)
 
void setGeometry (const QRect &rect)
 
void setGeometry (int x, int y, int w, int h)
 
void setGraphicsEffect (QGraphicsEffect *effect)
 
void setInputMethodHints (Qt::InputMethodHints hints)
 
void setLayout (QLayout *layout)
 
void setLayoutDirection (Qt::LayoutDirection direction)
 
void setLocale (const QLocale &locale)
 
void setMask (const QBitmap &bitmap)
 
void setMask (const QRegion &region)
 
void setMaximumHeight (int maxh)
 
void setMaximumSize (const QSize &size)
 
void setMaximumSize (int maxw, int maxh)
 
void setMaximumWidth (int maxw)
 
void setMinimumHeight (int minh)
 
void setMinimumSize (const QSize &size)
 
void setMinimumSize (int minw, int minh)
 
void setMinimumWidth (int minw)
 
void setMouseTracking (bool enable)
 
void setPalette (const QPalette &palette)
 
void setParent (QWidget *parent)
 
void setParent (QWidget *parent, Qt::WindowFlags flags)
 
void setShortcutAutoRepeat (int id, bool enable=true)
 
void setShortcutEnabled (int id, bool enable=true)
 
void setSizeIncrement (const QSize &size)
 
void setSizeIncrement (int w, int h)
 
void setSizePolicy (QSizePolicy policy)
 
void setSizePolicy (QSizePolicy::Policy horizontal, QSizePolicy::Policy vertical)
 
void setStatusTip (const QString &data)
 
void setStyle (QStyle *style)
 
void setToolTip (const QString &data)
 
void setToolTipDuration (int msec)
 
void setUpdatesEnabled (bool enable)
 
void setWhatsThis (const QString &str)
 
void setWindowFilePath (const QString &filePath)
 
void setWindowFlags (Qt::WindowFlags flags)
 
void setWindowIcon (const QIcon &icon)
 
void setWindowModality (Qt::WindowModality windowModality)
 
void setWindowOpacity (qreal level)
 
void setWindowRole (const QString &role)
 
void setWindowState (Qt::WindowStates windowState)
 
QSize size () const
 
QSize sizeIncrement () const
 
QSizePolicy sizePolicy () const
 
void stackUnder (QWidget *widget)
 
QString statusTip () const
 
QStylestyle () const
 
QString styleSheet () const
 
bool testAttribute (Qt::WidgetAttribute attribute) const
 
QString toolTip () const
 
int toolTipDuration () const
 
QWidget * topLevelWidget () const
 
bool underMouse () const
 
void ungrabGesture (Qt::GestureType gestureType)
 
void unsetCursor ()
 
void unsetLayoutDirection ()
 
void unsetLocale ()
 
void update (const QRect &rect)
 
void update (const QRegion &region)
 
void update (int x, int y, int w, int h)
 
void updateGeometry ()
 
bool updatesEnabled () const
 
QRegion visibleRegion () const
 
QString whatsThis () const
 
int width () const
 
QWidget * window () const
 
QString windowFilePath () const
 
Qt::WindowFlags windowFlags () const
 
QWindowwindowHandle () const
 
QIcon windowIcon () const
 
Qt::WindowModality windowModality () const
 
qreal windowOpacity () const
 
QString windowRole () const
 
Qt::WindowStates windowState () const
 
QString windowTitle () const
 
Qt::WindowType windowType () const
 
WId winId () const
 
int x () const
 
int y () const
 
- Public Methods inherited from QObject
 QObject (QObject *parent=nullptr)
 
 ~QObject ()
 
bool blockSignals (bool block)
 
const QList< QObject * > & children () const
 
bool connect (const QObject *sender, const QString &signalMethod, const QString &location, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
bool connect (const QObject *sender, const QString &signalMethod, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
bool disconnect (const QObject *receiver, const QString &slotMethod=QString ()) const
 
bool disconnect (const QString &signalMethod, const QString &location, const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const
 
bool disconnect (const QString &signalMethod=QString (), const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const
 
void dumpObjectInfo ()
 
void dumpObjectTree ()
 
QList< QStringdynamicPropertyNames () const
 
virtual bool event (QEvent *event)
 
virtual bool eventFilter (QObject *watched, QEvent *event)
 
template<typename T >
findChild (const QString &childName=QString ()) const
 
template<class T >
QList< T > findChildren (const QRegularExpression &regExp, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
 
template<class T >
QList< T > findChildren (const QString &objName=QString (), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
 
bool inherits (const QString &className) const
 
void installEventFilter (QObject *filterObj)
 
bool isWidgetType () const
 
bool isWindowType () const
 
void killTimer (int id)
 
const QMetaObjectmetaObject () const
 
void moveToThread (QThread *targetThread)
 
QString objectName () const
 
QObject * parent () const
 
template<class T = QVariant>
property (const QString &name) const
 
void removeEventFilter (QObject *obj)
 
void setObjectName (const QString &name)
 
void setParent (QObject *parent)
 
bool setProperty (const QString &name, const QVariant &value)
 
bool signalsBlocked () const
 
int startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
 
QThreadthread () const
 
- Public Methods inherited from QPaintDevice
virtual ~QPaintDevice ()
 
int colorCount () const
 
int depth () const
 
int devicePixelRatio () const
 
qreal devicePixelRatioF () const
 
int height () const
 
int heightMM () const
 
int logicalDpiX () const
 
int logicalDpiY () const
 
bool paintingActive () const
 
int physicalDpiX () const
 
int physicalDpiY () const
 
int width () const
 
int widthMM () const
 

Protected Slots

void forceShow ()
 
- Protected Slots inherited from QWidget
void updateMicroFocus ()
 

Protected Methods

void changeEvent (QEvent *event) override
 
void closeEvent (QCloseEvent *event) override
 
void showEvent (QShowEvent *event) override
 
- Protected Methods inherited from QDialog
void contextMenuEvent (QContextMenuEvent *event) override
 
bool eventFilter (QObject *object, QEvent *event) override
 
void keyPressEvent (QKeyEvent *event) override
 
void resizeEvent (QResizeEvent *event) override
 
- Protected Methods inherited from QWidget
virtual void actionEvent (QActionEvent *event)
 
void create (WId window=0, bool initializeWindow=true, bool destroyOldWindow=true)
 
void destroy (bool destroyWindow=true, bool destroySubWindows=true)
 
virtual void dragEnterEvent (QDragEnterEvent *event)
 
virtual void dragLeaveEvent (QDragLeaveEvent *event)
 
virtual void dragMoveEvent (QDragMoveEvent *event)
 
virtual void dropEvent (QDropEvent *event)
 
virtual void enterEvent (QEvent *event)
 
bool event (QEvent *event) override
 
virtual void focusInEvent (QFocusEvent *event)
 
bool focusNextChild ()
 
virtual bool focusNextPrevChild (bool next)
 
virtual void focusOutEvent (QFocusEvent *event)
 
bool focusPreviousChild ()
 
virtual void hideEvent (QHideEvent *event)
 
void initPainter (QPainter *painter) const override
 
virtual void inputMethodEvent (QInputMethodEvent *event)
 
virtual void keyReleaseEvent (QKeyEvent *event)
 
virtual void leaveEvent (QEvent *event)
 
int metric (PaintDeviceMetric metric) const override
 
virtual void mouseDoubleClickEvent (QMouseEvent *event)
 
virtual void mouseMoveEvent (QMouseEvent *event)
 
virtual void mousePressEvent (QMouseEvent *event)
 
virtual void mouseReleaseEvent (QMouseEvent *event)
 
virtual void moveEvent (QMoveEvent *event)
 
virtual bool nativeEvent (const QByteArray &eventType, void *message, long *result)
 
virtual void paintEvent (QPaintEvent *event)
 
virtual void tabletEvent (QTabletEvent *event)
 
virtual void wheelEvent (QWheelEvent *event)
 
- Protected Methods inherited from QObject
virtual void childEvent (QChildEvent *event)
 
virtual void connectNotify (const QMetaMethod &signalMethod) const
 
virtual void customEvent (QEvent *event)
 
virtual void disconnectNotify (const QMetaMethod &signalMethod) const
 
bool isSignalConnected (const QMetaMethod &signalMethod) const
 
int receivers (const QString &signal) const
 
QObject * sender () const
 
int senderSignalIndex () const
 
virtual void timerEvent (QTimerEvent *event)
 
- Protected Methods inherited from QPaintDevice
 QPaintDevice ()
 

Properties

 autoClose
 
 autoReset
 
 labelText
 
 maximum
 
 minimum
 
 minimumDuration
 
 value
 
 wasCanceled
 
- Properties inherited from QDialog
 modal
 
 sizeGripEnabled
 
- Properties inherited from QWidget
 acceptDrops
 
 accessibleDescription
 
 accessibleName
 
 autoFillBackground
 
 baseSize
 
 childrenRect
 
 childrenRegion
 
 contextMenuPolicy
 
 cursor
 
 enabled
 
 focus
 
 focusPolicy
 
 font
 
 frameGeometry
 
 frameSize
 
 fullScreen
 
 geometry
 
 height
 
 inputMethodHints
 
 isActiveWindow
 
 layoutDirection
 
 locale
 
 maximized
 
 maximumHeight
 
 maximumSize
 
 maximumWidth
 
 minimized
 
 minimumHeight
 
 minimumSize
 
 minimumSizeHint
 
 minimumWidth
 
 modal
 
 mouseTracking
 
 normalGeometry
 
 palette
 
 pos
 
 rect
 
 size
 
 sizeHint
 
 sizeIncrement
 
 sizePolicy
 
 statusTip
 
 styleSheet
 
 toolTip
 
 updatesEnabled
 
 visible
 
 whatsThis
 
 width
 
 windowFilePath
 
 windowFlags
 
 windowIcon
 
 windowIconText
 
 windowModality
 
 windowModified
 
 windowOpacity
 
 windowTitle
 
 x
 
 y
 
- Properties inherited from QObject
 objectName
 

Additional Inherited Members

- Public Types inherited from QDialog
enum  DialogCode
 
- Public Types inherited from QWidget
enum  RenderFlag
 
- Public Types inherited from QPaintDevice
enum  PaintDeviceMetric
 
- Static Public Methods inherited from QWidget
static QWidget * createWindowContainer (QWindow *window, QWidget *parent=nullptr, Qt::WindowFlags flags=Qt::EmptyFlag)
 
static QWidget * find (WId id)
 
static QWidget * keyboardGrabber ()
 
static QWidget * mouseGrabber ()
 
static void setTabOrder (QWidget *firstWidget, QWidget *secondWidget)
 
- Static Public Methods inherited from QObject
static bool connect (const QObject *sender, const QMetaMethod &signalMethod, const QObject *receiver, const QMetaMethod &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
static bool connect (const QObject *sender, const QString &signalMethod, const QObject *receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection, const QString &location=QString ())
 
static bool connect (const QObject *sender, const QString &signalMethod, const QString &location, const QObject *receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool connect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, SlotReturn (SlotClass::*slotMethod)(SlotArgs...), Qt::ConnectionType type=Qt::AutoConnection)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool connect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, T slotLambda, Qt::ConnectionType type=Qt::AutoConnection)
 
static bool disconnect (const QObject *sender, const QMetaMethod &signalMethod, const QObject *receiver, const QMetaMethod &slotMethod)
 
static bool disconnect (const QObject *sender, const QString &signalMethod, const QObject *receiver, const QString &slotMethod)
 
static bool disconnect (const QObject *sender, const QString &signalMethod, const QString &location, const QObject *receiver, const QString &slotMethod)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, SlotReturn (SlotClass::*slotMethod)(SlotArgs...))
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver >
static bool disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, std::nullptr_t slotMethod=nullptr)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, T slotMethod)
 
static QMetaObjectstaticMetaObject ()
 
static QString tr (const char *text, const char *comment=nullptr, std::optional< int > numArg=std::optional< int >())
 

Detailed 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 setMinimum() and setMaximum() or the constructor to set the number of "steps" in the operation and call setValue() as the operation progresses. The number of steps 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 the value set by setMinimum(), and the progress dialog shows that the operation has finished when you call setValue() with the value set by setMaximum() as its argument.

The dialog automatically resets and hides itself at the end of the operation. Use setAutoReset() and setAutoClose() to change this behavior. Note that if you set a new maximum (using setMaximum() or setRange()) that equals your current value(), the dialog will not close regardless.

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

Compared to a modeless QProgressDialog, a modal QProgressDialog is simpler to use for the programmer. Do the operation in a loop, call setValue() at intervals, and check for cancellation with wasCanceled(). For example:

QProgressDialog progress("Copying files...", "Abort Copy", 0, numFiles, this);
progress.setWindowModality(Qt::WindowModal);
for (int i = 0; i < numFiles; i++) {
progress.setValue(i);
if (progress.wasCanceled())
break;
//... copy one file
}
progress.setValue(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 setValue() at intervals.

// Operation constructor
Operation::Operation(QObject *parent)
: QObject(parent), steps(0)
{
pd = new QProgressDialog("Operation in progress.", "Cancel", 0, 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->setValue(steps);
//... perform one percent of the operation
steps++;
if (steps > pd->maximum()) {
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.

See also
QDialog, QProgressBar

Constructor & Destructor Documentation

QProgressDialog::QProgressDialog ( QWidget parent = nullptr,
Qt::WindowFlags  flags = Qt::EmptyFlag 
)
explicit

Constructs a progress dialog. The values for parent and flags are passed to the QDialog constructor

These are the default settings.

  • Dialog label text is empty
  • Cancel button text is (translated) "Cancel"
  • Minimum is 0
  • Maximum is 100
See also
setLabelText(), setCancelButtonText(), setCancelButton(), setMinimum(), setMaximum()
QProgressDialog::QProgressDialog ( const QString labelText,
const QString cancelButtonText,
int  minimum,
int  maximum,
QWidget parent = nullptr,
Qt::WindowFlags  flags = Qt::EmptyFlag 
)

Constructs a progress dialog. The values for parent and flags are passed to the QDialog constructor.

The labelText is the text used to remind the user what is progressing. The cancelButtonText is the text to display on the cancel button. If an empty string is passed then no cancel button is shown.

The minimum and maximum is the 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 minimum value would be 0, and the maximum would be

  1. Before examining the first file, call setValue(0). As each file is processed call setValue(1), setValue(2), etc., finally calling setValue(50) after examining the last file.
See also
setLabelText(), setLabel(), setCancelButtonText(), setCancelButton(), setMinimum(), setMaximum()
QProgressDialog::~QProgressDialog ( )

Destroys the progress dialog.

Method Documentation

bool QProgressDialog::autoClose ( ) const

Property documentation pending.

bool QProgressDialog::autoReset ( ) const

Property documentation pending.

void QProgressDialog::cancel ( )
slot

Resets the progress dialog. The property 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::changeEvent ( QEvent event)
overrideprotectedvirtual

Reimplemented from QWidget::changeEvent().

Reimplemented from QWidget.

void QProgressDialog::closeEvent ( QCloseEvent event)
overrideprotectedvirtual

Reimplemented from QWidget::closeEvent().

Reimplemented from QDialog.

void QProgressDialog::forceShow ( )
protectedslot

Shows the dialog if it is still hidden after the algorithm has been started and minimumDuration milliseconds have passed.

See also
setMinimumDuration()
QString QProgressDialog::labelText ( ) const

Property documentation pending.

int QProgressDialog::maximum ( ) const

Property documentation pending.

int QProgressDialog::minimum ( ) const

Property documentation pending.

int QProgressDialog::minimumDuration ( ) const

Property documentation pending.

void QDialog::open ( )
usingslot

Shows the dialog as a window modal dialog, returning immediately.

See also
exec(), show(), result(), setWindowModality()
void QProgressDialog::open ( QObject receiver,
const QString member 
)

Opens the dialog and connects its accepted() signal to the slot specified by receiver and member.

The signal will be disconnected from the slot when the dialog is closed.

void QProgressDialog::reset ( )
slot

Resets the progress dialog. The progress dialog becomes hidden if autoClose() is true.

See also
setAutoClose(), setAutoReset()
void QProgressDialog::setAutoClose ( bool  close)

Property documentation pending.

void QProgressDialog::setAutoReset ( bool  reset)

Property documentation pending.

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 button)

Sets the cancel button to the push button, button. 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. If 0 is passed then no cancel button will be shown.

See also
setCancelButtonText()
void QProgressDialog::setCancelButtonCentered ( bool  value = true)

Centers the cancel button horizontally if value is true. If value is false the button will be aligned to the right side.

void QProgressDialog::setCancelButtonText ( const QString text)
slot

Sets the cancel button's label to text. If the text is set to an empty string then it will cause the cancel button to be hidden and deleted.

See also
setCancelButton()
void QProgressDialog::setLabel ( QLabel label)

Sets the label of the dialog 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
setLabelText()
void QProgressDialog::setLabelText ( const QString text)
slot

Property documentation pending.

void QProgressDialog::setMaximum ( int  maximum)
slot

Property documentation pending.

void QProgressDialog::setMinimum ( int  minimum)
slot

Property documentation pending.

void QProgressDialog::setMinimumDuration ( int  ms)
slot

Property documentation pending.

void QProgressDialog::setRange ( int  minimum,
int  maximum 
)
slot

Sets the range for the progress dialog to minimum and maximum. If the maximum is less than the minimum, the maximum value is ignored. If the current progress is outside the new range, the progress dialog calls reset().

See also
minimum, maximum
void QProgressDialog::setValue ( int  progress)
slot

Property documentation pending.

void QProgressDialog::showEvent ( QShowEvent event)
overrideprotectedvirtual

Reimplemented from QWidget::showEvent().

Reimplemented from QDialog.

QSize QProgressDialog::sizeHint ( ) const
overridevirtual

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.

Reimplemented from QDialog.

int QProgressDialog::value ( ) const

Property documentation pending.

bool QProgressDialog::wasCanceled ( ) const

Property documentation pending.

Property Documentation

QProgressDialog::autoClose

This property holds whether the dialog gets hidden by reset(). The default is true.

See also
setAutoReset()
PropertiesClass Methods
read autoClose
write setAutoClose
QProgressDialog::autoReset

This property holds whether the progress dialog calls reset() as soon as value() equals maximum().

The default is true.

See also
setAutoClose()
PropertiesClass Methods
read autoReset
write setAutoReset
QProgressDialog::labelText

This property holds the label's text.

The default text is an empty string.

PropertiesClass Methods
read labelText
write setLabelText
QProgressDialog::maximum

This property holds the highest value represented by the progress bar.

The default is 0.

See also
minimum, setRange()
PropertiesClass Methods
read maximum
write setMaximum
QProgressDialog::minimum

This property holds the lowest value represented by the progress bar.

The default is 0.

See also
maximum, setRange()
PropertiesClass Methods
read minimum
write setMinimum
QProgressDialog::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.

PropertiesClass Methods
read minimumDuration
write setMinimumDuration
QProgressDialog::value

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::maximum(); you can call setValue() any number of times in-between.

Warning
If the progress dialog is modal (see QProgressDialog::QProgressDialog()), setValue() calls QApplication::processEvents(), so take care that this does not cause undesirable recursion in your code. For example, do not use a QProgressDialog inside a paintEvent().
See also
minimum, maximum
PropertiesClass Methods
read value
write setValue
QProgressDialog::wasCanceled

This property holds whether the dialog was canceled.

PropertiesClass Methods
read wasCanceled