QGraphicsTextItem Class

The QGraphicsTextItem class provides a text item that you can add to a QGraphicsScene to display formatted text. More...

Header: #include <QGraphicsTextItem>
CMake: find_package(Qt6 REQUIRED COMPONENTS Widgets)
target_link_libraries(mytarget PRIVATE Qt6::Widgets)
qmake: QT += widgets
Inherits: QGraphicsObject

Public Types

enum anonymous { Type }

Properties

Public Functions

QGraphicsTextItem(QGraphicsItem *parent = nullptr)
QGraphicsTextItem(const QString &text, QGraphicsItem *parent = nullptr)
virtual ~QGraphicsTextItem()
void adjustSize()
QColor defaultTextColor() const
QTextDocument *document() const
QFont font() const
bool openExternalLinks() const
void setDefaultTextColor(const QColor &col)
void setDocument(QTextDocument *document)
void setFont(const QFont &font)
void setHtml(const QString &text)
void setOpenExternalLinks(bool open)
void setPlainText(const QString &text)
void setTabChangesFocus(bool b)
void setTextCursor(const QTextCursor &cursor)
void setTextInteractionFlags(Qt::TextInteractionFlags flags)
void setTextWidth(qreal width)
bool tabChangesFocus() const
QTextCursor textCursor() const
Qt::TextInteractionFlags textInteractionFlags() const
qreal textWidth() const
QString toHtml() const
QString toPlainText() const

Reimplemented Public Functions

virtual QRectF boundingRect() const override
virtual bool contains(const QPointF &point) const override
virtual bool isObscuredBy(const QGraphicsItem *item) const override
virtual QPainterPath opaqueArea() const override
virtual void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) override
virtual QPainterPath shape() const override
virtual int type() const override

Signals

void linkActivated(const QString &link)
void linkHovered(const QString &link)

Reimplemented Protected Functions

virtual void contextMenuEvent(QGraphicsSceneContextMenuEvent *event) override
virtual void dragEnterEvent(QGraphicsSceneDragDropEvent *event) override
virtual void dragLeaveEvent(QGraphicsSceneDragDropEvent *event) override
virtual void dragMoveEvent(QGraphicsSceneDragDropEvent *event) override
virtual void dropEvent(QGraphicsSceneDragDropEvent *event) override
virtual void focusInEvent(QFocusEvent *event) override
virtual void focusOutEvent(QFocusEvent *event) override
virtual void hoverEnterEvent(QGraphicsSceneHoverEvent *event) override
virtual void hoverLeaveEvent(QGraphicsSceneHoverEvent *event) override
virtual void hoverMoveEvent(QGraphicsSceneHoverEvent *event) override
virtual void inputMethodEvent(QInputMethodEvent *event) override
virtual QVariant inputMethodQuery(Qt::InputMethodQuery query) const override
virtual void keyPressEvent(QKeyEvent *event) override
virtual void keyReleaseEvent(QKeyEvent *event) override
virtual void mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event) override
virtual void mouseMoveEvent(QGraphicsSceneMouseEvent *event) override
virtual void mousePressEvent(QGraphicsSceneMouseEvent *event) override
virtual void mouseReleaseEvent(QGraphicsSceneMouseEvent *event) override
virtual bool sceneEvent(QEvent *event) override

Detailed Description

If you only need to show plain text in an item, consider using QGraphicsSimpleTextItem instead.

To set the item's text, pass a QString to QGraphicsTextItem's constructor, or call setHtml()/setPlainText().

QGraphicsTextItem uses the text's formatted size and the associated font to provide a reasonable implementation of boundingRect(), shape(), and contains(). You can set the font by calling setFont().

It is possible to make the item editable by setting the Qt::TextEditorInteraction flag using setTextInteractionFlags().

The item's preferred text width can be set using setTextWidth() and obtained using textWidth().

Note: In order to align HTML text in the center, the item's text width must be set. Otherwise, you can call adjustSize() after setting the item's text.

Note: QGraphicsTextItem accepts hover events by default. You can change this with setAcceptHoverEvents().

See also QGraphicsSimpleTextItem, QGraphicsPathItem, QGraphicsRectItem, QGraphicsEllipseItem, QGraphicsPixmapItem, QGraphicsPolygonItem, QGraphicsLineItem, and Graphics View Framework.

Member Type Documentation

enum QGraphicsTextItem::anonymous

The value returned by the virtual type() function.

ConstantValueDescription
QGraphicsTextItem::Type8A graphics text item

Property Documentation

Specifies whether QGraphicsTextItem should automatically open links using QDesktopServices::openUrl() instead of emitting the linkActivated signal.

The default value is false.

Access functions:

bool openExternalLinks() const
void setOpenExternalLinks(bool open)

textCursor : QTextCursor

This property represents the visible text cursor in an editable text item.

By default, if the item's text has not been set, this property contains a null text cursor; otherwise it contains a text cursor placed at the start of the item's document.

Access functions:

QTextCursor textCursor() const
void setTextCursor(const QTextCursor &cursor)

Member Function Documentation

[explicit] QGraphicsTextItem::QGraphicsTextItem(QGraphicsItem *parent = nullptr)

Constructs a QGraphicsTextItem. parent is passed to QGraphicsItem's constructor.

See also QGraphicsScene::addItem().

[explicit] QGraphicsTextItem::QGraphicsTextItem(const QString &text, QGraphicsItem *parent = nullptr)

Constructs a QGraphicsTextItem, using text as the default plain text. parent is passed to QGraphicsItem's constructor.

See also QGraphicsScene::addItem().

[virtual noexcept] QGraphicsTextItem::~QGraphicsTextItem()

Destroys the QGraphicsTextItem.

void QGraphicsTextItem::adjustSize()

Adjusts the text item to a reasonable size.

[override virtual] QRectF QGraphicsTextItem::boundingRect() const

Reimplements: QGraphicsItem::boundingRect() const.

[override virtual] bool QGraphicsTextItem::contains(const QPointF &point) const

Reimplements: QGraphicsItem::contains(const QPointF &point) const.

[override virtual protected] void QGraphicsTextItem::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)

Reimplements: QGraphicsItem::contextMenuEvent(QGraphicsSceneContextMenuEvent *event).

QColor QGraphicsTextItem::defaultTextColor() const

Returns the default text color that is used for unformatted text.

See also setDefaultTextColor().

QTextDocument *QGraphicsTextItem::document() const

Returns the item's text document.

See also setDocument().

[override virtual protected] void QGraphicsTextItem::dragEnterEvent(QGraphicsSceneDragDropEvent *event)

Reimplements: QGraphicsItem::dragEnterEvent(QGraphicsSceneDragDropEvent *event).

[override virtual protected] void QGraphicsTextItem::dragLeaveEvent(QGraphicsSceneDragDropEvent *event)

Reimplements: QGraphicsItem::dragLeaveEvent(QGraphicsSceneDragDropEvent *event).

[override virtual protected] void QGraphicsTextItem::dragMoveEvent(QGraphicsSceneDragDropEvent *event)

Reimplements: QGraphicsItem::dragMoveEvent(QGraphicsSceneDragDropEvent *event).

[override virtual protected] void QGraphicsTextItem::dropEvent(QGraphicsSceneDragDropEvent *event)

Reimplements: QGraphicsItem::dropEvent(QGraphicsSceneDragDropEvent *event).

[override virtual protected] void QGraphicsTextItem::focusInEvent(QFocusEvent *event)

Reimplements: QGraphicsItem::focusInEvent(QFocusEvent *event).

[override virtual protected] void QGraphicsTextItem::focusOutEvent(QFocusEvent *event)

Reimplements: QGraphicsItem::focusOutEvent(QFocusEvent *event).

QFont QGraphicsTextItem::font() const

Returns the item's font, which is used to render the text.

See also setFont().

[override virtual protected] void QGraphicsTextItem::hoverEnterEvent(QGraphicsSceneHoverEvent *event)

Reimplements: QGraphicsItem::hoverEnterEvent(QGraphicsSceneHoverEvent *event).

[override virtual protected] void QGraphicsTextItem::hoverLeaveEvent(QGraphicsSceneHoverEvent *event)

Reimplements: QGraphicsItem::hoverLeaveEvent(QGraphicsSceneHoverEvent *event).

[override virtual protected] void QGraphicsTextItem::hoverMoveEvent(QGraphicsSceneHoverEvent *event)

Reimplements: QGraphicsItem::hoverMoveEvent(QGraphicsSceneHoverEvent *event).

[override virtual protected] void QGraphicsTextItem::inputMethodEvent(QInputMethodEvent *event)

Reimplements: QGraphicsItem::inputMethodEvent(QInputMethodEvent *event).

[override virtual protected] QVariant QGraphicsTextItem::inputMethodQuery(Qt::InputMethodQuery query) const

Reimplements: QGraphicsItem::inputMethodQuery(Qt::InputMethodQuery query) const.

[override virtual] bool QGraphicsTextItem::isObscuredBy(const QGraphicsItem *item) const

Reimplements: QGraphicsItem::isObscuredBy(const QGraphicsItem *item) const.

[override virtual protected] void QGraphicsTextItem::keyPressEvent(QKeyEvent *event)

Reimplements: QGraphicsItem::keyPressEvent(QKeyEvent *event).

[override virtual protected] void QGraphicsTextItem::keyReleaseEvent(QKeyEvent *event)

Reimplements: QGraphicsItem::keyReleaseEvent(QKeyEvent *event).

[signal] void QGraphicsTextItem::linkActivated(const QString &link)

This signal is emitted when the user clicks on a link on a text item that enables Qt::LinksAccessibleByMouse or Qt::LinksAccessibleByKeyboard. link is the link that was clicked.

See also setTextInteractionFlags().

[signal] void QGraphicsTextItem::linkHovered(const QString &link)

This signal is emitted when the user hovers over a link on a text item that enables Qt::LinksAccessibleByMouse. link is the link that was hovered over.

See also setTextInteractionFlags().

[override virtual protected] void QGraphicsTextItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)

Reimplements: QGraphicsItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event).

[override virtual protected] void QGraphicsTextItem::mouseMoveEvent(QGraphicsSceneMouseEvent *event)

Reimplements: QGraphicsItem::mouseMoveEvent(QGraphicsSceneMouseEvent *event).

[override virtual protected] void QGraphicsTextItem::mousePressEvent(QGraphicsSceneMouseEvent *event)

Reimplements: QGraphicsItem::mousePressEvent(QGraphicsSceneMouseEvent *event).

[override virtual protected] void QGraphicsTextItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)

Reimplements: QGraphicsItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *event).

[override virtual] QPainterPath QGraphicsTextItem::opaqueArea() const

Reimplements: QGraphicsItem::opaqueArea() const.

[override virtual] void QGraphicsTextItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)

Reimplements: QGraphicsItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget).

[override virtual protected] bool QGraphicsTextItem::sceneEvent(QEvent *event)

Reimplements: QGraphicsItem::sceneEvent(QEvent *event).

void QGraphicsTextItem::setDefaultTextColor(const QColor &col)

Sets the color for unformatted text to col.

See also defaultTextColor().

void QGraphicsTextItem::setDocument(QTextDocument *document)

Sets the text document document on the item.

See also document().

void QGraphicsTextItem::setFont(const QFont &font)

Sets the font used to render the text item to font.

See also font().

void QGraphicsTextItem::setHtml(const QString &text)

Sets the item's text to text, assuming that text is HTML formatted. If the item has keyboard input focus, this function will also call ensureVisible() to ensure that the text is visible in all viewports.

See also toHtml(), hasFocus(), and QGraphicsSimpleTextItem.

void QGraphicsTextItem::setPlainText(const QString &text)

Sets the item's text to text. If the item has keyboard input focus, this function will also call ensureVisible() to ensure that the text is visible in all viewports.

See also toHtml() and hasFocus().

void QGraphicsTextItem::setTabChangesFocus(bool b)

If b is true, the Tab key will cause the widget to change focus; otherwise, the tab key will insert a tab into the document.

In some occasions text edits should not allow the user to input tabulators or change indentation using the Tab key, as this breaks the focus chain. The default is false.

See also tabChangesFocus(), ItemIsFocusable, and textInteractionFlags().

void QGraphicsTextItem::setTextInteractionFlags(Qt::TextInteractionFlags flags)

Sets the flags flags to specify how the text item should react to user input.

The default for a QGraphicsTextItem is Qt::NoTextInteraction. This function also affects the ItemIsFocusable QGraphicsItem flag by setting it if flags is different from Qt::NoTextInteraction and clearing it otherwise.

By default, the text is read-only. To transform the item into an editor, set the Qt::TextEditable flag.

See also textInteractionFlags().

void QGraphicsTextItem::setTextWidth(qreal width)

Sets the preferred width for the item's text. If the actual text is wider than the specified width then it will be broken into multiple lines.

If width is set to -1 then the text will not be broken into multiple lines unless it is enforced through an explicit line break or a new paragraph.

The default value is -1.

Note that QGraphicsTextItem keeps a QTextDocument internally, which is used to calculate the text width.

See also textWidth() and QTextDocument::setTextWidth().

[override virtual] QPainterPath QGraphicsTextItem::shape() const

Reimplements: QGraphicsItem::shape() const.

bool QGraphicsTextItem::tabChangesFocus() const

Returns true if the Tab key will cause the widget to change focus; otherwise, false is returned.

By default, this behavior is disabled, and this function will return false.

See also setTabChangesFocus().

Qt::TextInteractionFlags QGraphicsTextItem::textInteractionFlags() const

Returns the current text interaction flags.

See also setTextInteractionFlags().

qreal QGraphicsTextItem::textWidth() const

Returns the text width.

The width is calculated with the QTextDocument that QGraphicsTextItem keeps internally.

See also setTextWidth() and QTextDocument::textWidth().

QString QGraphicsTextItem::toHtml() const

Returns the item's text converted to HTML, or an empty QString if no text has been set.

See also setHtml().

QString QGraphicsTextItem::toPlainText() const

Returns the item's text converted to plain text, or an empty QString if no text has been set.

See also setPlainText().

[override virtual] int QGraphicsTextItem::type() const

Reimplements: QGraphicsItem::type() const.