QMdiArea Class

The QMdiArea class provides an area in which sub-windows are shown, for an application with many documents. More…

List of all members, including inherited members

Public Types

Public Functions

Reimplemented Public Functions

Public Slots

Signals

Reimplemented Protected Functions

Detailed Description

An MDI area holds QMdiSubWindow windows: it lays them out, keeps one of them active, and can tile or cascade them. It is usually the central widget of a QMainWindow:

auto *area = new QMdiArea;
window.setCentralWidget(area);
QMdiSubWindow *notes = area->addSubWindow(new QPlainTextEdit);
notes->setWindowTitle("Notes");
notes->show();
connect(area, &QMdiArea::subWindowActivated, [](QMdiSubWindow *w) { updateMenus(w); });

In TabbedView mode the area shows a tab bar with a tab for each sub-window, and the active sub-window fills the area without its frame.

See also QMdiSubWindow.

Differences from Qt

Member Type Documentation

enum QMdiArea::AreaOption

Options of the area. AreaOptions is a typedef for QFlags<AreaOption>.

typedef QMdiArea::AreaOptions

The AreaOptions type is a typedef for QFlags<AreaOption>. It stores an OR combination of AreaOption values.

enum QMdiArea::ViewMode

How the sub-windows are shown.

enum QMdiArea::WindowOrder

The orders of subWindowList(), and of activateNextSubWindow().

Member Function Documentation

[explicit] QMdiArea::QMdiArea(QWidget *parent = nullptr)

Constructs an empty MDI area with the given parent.

[override] QMdiArea::~QMdiArea()

Destroys the area and its sub-windows.

[slot] void QMdiArea::activateNextSubWindow()

Activates the visible sub-window after the active one in the activation order, going round at the end.

[slot] void QMdiArea::activatePreviousSubWindow()

Activates the visible sub-window before the active one in the activation order, going round at the start.

WindowOrder QMdiArea::activationOrder() const

Returns the order of activateNextSubWindow(), CreationOrder by default.

QMdiSubWindow * QMdiArea::activeSubWindow() const

Returns the active sub-window, or nullptr.

QMdiSubWindow * QMdiArea::addSubWindow(QWidget *widget, Qt::WindowFlags flags = Qt::WindowFlags())

Adds widget to the area in a new sub-window with the window flags, and returns the sub-window. A QMdiSubWindow is added as it is. The sub-window is shown with the area; if the area is visible already, call show() on it. The first sub-window becomes active.

See also removeSubWindow().

QBrush QMdiArea::background() const

Returns the brush that fills the area behind the sub-windows; by default the dark color of the palette.

[slot] void QMdiArea::cascadeSubWindows()

Lays the visible sub-windows out one behind the other, each a step further down and to the right.

See also tileSubWindows().

[slot] void QMdiArea::closeActiveSubWindow()

Closes the active sub-window.

[slot] void QMdiArea::closeAllSubWindows()

Closes all the sub-windows. A sub-window whose widget ignores the close event stays.

QMdiSubWindow * QMdiArea::currentSubWindow() const

Returns the sub-window that is current: the active one, or the one that was active last while the window of the area was not active.

[override] QSize QMdiArea::minimumSizeHint() const

Reimplements QAbstractScrollArea::minimumSizeHint().

void QMdiArea::removeSubWindow(QWidget *widget)

Removes widget from the area without deleting it. For a QMdiSubWindow, the sub-window leaves the area and no longer has a parent; for the widget of a sub-window, the widget leaves its sub-window, which stays.

See also addSubWindow().

[override, protected] void QMdiArea::resizeEvent(QResizeEvent *event)

Reimplements QAbstractScrollArea::resizeEvent().

void QMdiArea::setActivationOrder(WindowOrder order)

Sets the order of activateNextSubWindow() to order.

[slot] void QMdiArea::setActiveSubWindow(QMdiSubWindow *window)

Makes window the active sub-window: it is raised, gets the focus, and the one that was active stops being so. Emits subWindowActivated() if it changes. With nullptr no sub-window is active.

See also activeSubWindow().

void QMdiArea::setBackground(const QBrush &background)

Sets the brush that fills the area behind the sub-windows to background.

void QMdiArea::setOption(AreaOption option, bool on = true)

Sets option if on is true, and clears it otherwise.

void QMdiArea::setTabsClosable(bool closable)

Sets whether the tabs of the tabbed view have close buttons to closable.

void QMdiArea::setTabsMovable(bool movable)

Sets whether the tabs of the tabbed view can be dragged into another order to movable.

void QMdiArea::setViewMode(ViewMode mode)

Sets how the sub-windows are shown to mode.

[override] QSize QMdiArea::sizeHint() const

Reimplements QAbstractScrollArea::sizeHint().

[signal] void QMdiArea::subWindowActivated(QMdiSubWindow *window)

This signal is emitted when the active sub-window changes to window, which is nullptr if there is none.

QList<QMdiSubWindow *> QMdiArea::subWindowList(WindowOrder order = CreationOrder) const

Returns the sub-windows in the given order.

bool QMdiArea::tabsClosable() const

Returns whether the tabs of the tabbed view have close buttons. The default is false.

bool QMdiArea::tabsMovable() const

Returns whether the tabs of the tabbed view can be dragged into another order. The default is false.

bool QMdiArea::testOption(AreaOption option) const

Returns whether option is set.

[slot] void QMdiArea::tileSubWindows()

Lays the visible sub-windows out in a grid that fills the area.

See also cascadeSubWindows().

ViewMode QMdiArea::viewMode() const

Returns how the sub-windows are shown, SubWindowView by default.

[override, protected] bool QMdiArea::viewportEvent(QEvent *event)

Reimplements QAbstractScrollArea::viewportEvent().

The viewport is filled with the background, and maximized sub-windows follow its size.