QGraphicsObject Class
The QGraphicsObject class provides a base class for all graphics items that require signals, slots and properties. 更多...
| 头文件: | #include <QGraphicsObject> |
| qmake: | QT += widgets |
| 开始支持版本: | Qt 4.6 |
| 基类: | QObject and QGraphicsItem |
| 派生类: |
属性
- 1 个属性继承自 QObject
公有函数
| QGraphicsObject(QGraphicsItem *parent = Q_NULLPTR) | |
| ~QGraphicsObject() | |
| void | grabGesture(Qt::GestureType gesture, Qt::GestureFlags flags = Qt::GestureFlags()) |
| void | ungrabGesture(Qt::GestureType gesture) |
- 32 个公有函数继承自 QObject
- 176 个公有函数继承自 QGraphicsItem
信号
| void | enabledChanged() |
| void | opacityChanged() |
| void | parentChanged() |
| void | rotationChanged() |
| void | scaleChanged() |
| void | visibleChanged() |
| void | xChanged() |
| void | yChanged() |
| void | zChanged() |
- 2 个信号继承自 QObject
重新实现的受保护函数
| virtual bool | event(QEvent *ev) |
- 9 个受保护的函数继承自 QObject
- 24 个受保护的函数继承自 QGraphicsItem
Protected Slots
| void | updateMicroFocus() |
其他继承的成员
- 1 个公有槽函数继承自 QObject
- 1 个公有变量继承自 QObject
- 10 个静态公有成员继承自 QObject
- 2 个静态公有成员继承自 QGraphicsItem
- 9 个受保护的函数继承自 QObject
- 24 个受保护的函数继承自 QGraphicsItem
- 2 个受保护的变量继承自 QObject
详细描述
The QGraphicsObject class provides a base class for all graphics items that require signals, slots and properties.
The class extends a QGraphicsItem with QObject's signal/slot and property mechanisms. It maps many of QGraphicsItem's basic setters and getters to properties and adds notification signals for many of them.
Parents and Children
Each graphics object can be constructed with a parent item. This ensures that the item will be destroyed when its parent item is destroyed. Although QGraphicsObject inherits from both QObject and QGraphicsItem, you should use the functions provided by QGraphicsItem, not QObject, to manage the relationships between parent and child items.
The relationships between items can be explored using the parentItem() and childItems() functions. In the hierarchy of items in a scene, the parentObject() and parentWidget() functions are the equivalent of the QWidget::parent() and QWidget::parentWidget() functions for QWidget subclasses.
参见 QGraphicsWidget.
属性
effect : QGraphicsEffect * const
This property holds the effect attached to this item
This property was introduced in Qt 4.7.
参见 QGraphicsItem::setGraphicsEffect() and QGraphicsItem::graphicsEffect().
enabled : const bool
This property holds whether the item is enabled or not
This property is declared in QGraphicsItem.
By default, this property is true.
Notifier signal:
| void | enabledChanged() |
参见 QGraphicsItem::isEnabled() and QGraphicsItem::setEnabled().
opacity : const qreal
This property holds the opacity of the item
Notifier signal:
| void | opacityChanged() |
参见 QGraphicsItem::setOpacity() and QGraphicsItem::opacity().
parent : QGraphicsObject * const
This property holds the parent of the item
Note: The item's parent is set independently of the parent object returned by QObject::parent().
Notifier signal:
| void | parentChanged() |
参见 QGraphicsItem::setParentItem() and QGraphicsItem::parentObject().
pos : const QPointF
This property holds the position of the item
Describes the items position.
参见 QGraphicsItem::setPos() and QGraphicsItem::pos().
rotation : const qreal
This property holds the rotation of the item in degrees.
This specifies how many degrees to rotate the item around its transformOrigin. The default rotation is 0 degrees (i.e. not rotated at all).
Notifier signal:
| void | rotationChanged() |
scale : const qreal
This property holds the scale of the item.
A scale of less than 1 means the item will be displayed smaller than normal, and a scale of greater than 1 means the item will be displayed larger than normal. A negative scale means the item will be mirrored.
By default, items are displayed at a scale of 1 (i.e. at their normal size).
Scaling is from the item's transformOrigin.
Notifier signal:
| void | scaleChanged() |
transformOriginPoint : const QPointF
This property holds the transformation origin
This property sets a specific point in the items coordiante system as the origin for scale and rotation.
参见 scale, rotation, and QGraphicsItem::transformOriginPoint().
visible : const bool
This property holds whether the item is visible or not
This property is declared in QGraphicsItem.
By default, this property is true.
Notifier signal:
| void | visibleChanged() |
参见 QGraphicsItem::isVisible() and QGraphicsItem::setVisible().
x : const qreal
This property holds the x position of the item
Describes the items x position.
Notifier signal:
| void | xChanged() |
参见 QGraphicsItem::setX() and setPos().
y : const qreal
This property holds the y position of the item
Describes the items y position.
Notifier signal:
| void | yChanged() |
参见 QGraphicsItem::setY() and setPos().
z : const qreal
This property holds the z value of the item
Describes the items z value.
Notifier signal:
| void | zChanged() |
参见 QGraphicsItem::setZValue() and zValue().
成员函数
QGraphicsObject::QGraphicsObject(QGraphicsItem *parent = Q_NULLPTR)
Constructs a QGraphicsObject with parent.
QGraphicsObject::~QGraphicsObject()
Destructor.
[signal] void QGraphicsObject::enabledChanged()
This signal gets emitted whenever the item get's enabled or disabled.
Note: Notifier signal for property enabled.
参见 isEnabled().
[virtual protected] bool QGraphicsObject::event(QEvent *ev)
重新实现 QObject::event().
void QGraphicsObject::grabGesture(Qt::GestureType gesture, Qt::GestureFlags flags = Qt::GestureFlags())
Subscribes the graphics object to the given gesture with specific flags.
参见 ungrabGesture() and QGestureEvent.
[signal] void QGraphicsObject::opacityChanged()
This signal gets emitted whenever the opacity of the item changes
Note: Notifier signal for property opacity.
参见 QGraphicsItem::opacity().
[signal] void QGraphicsObject::parentChanged()
This signal gets emitted whenever the parent of the item changes
Note: Notifier signal for property parent.
[signal] void QGraphicsObject::rotationChanged()
This signal gets emitted whenever the roation of the item changes.
Note: Notifier signal for property rotation.
[signal] void QGraphicsObject::scaleChanged()
This signal is emitted when the scale of the item changes.
Note: Notifier signal for property scale.
void QGraphicsObject::ungrabGesture(Qt::GestureType gesture)
Unsubscribes the graphics object from the given gesture.
参见 grabGesture() and QGestureEvent.
[protected slot] void QGraphicsObject::updateMicroFocus()
Updates the item's micro focus. This is slot for convenience.
This function was introduced in Qt 4.7.
参见 QInputMethod.
[signal] void QGraphicsObject::visibleChanged()
This signal gets emitted whenever the visibility of the item changes
Note: Notifier signal for property visible.
参见 visible.
[signal] void QGraphicsObject::xChanged()
This signal gets emitted whenever the x position of the item changes
Note: Notifier signal for property x.
参见 pos().
[signal] void QGraphicsObject::yChanged()
This signal gets emitted whenever the y position of the item changes.
Note: Notifier signal for property y.
参见 pos().
[signal] void QGraphicsObject::zChanged()
This signal gets emitted whenever the z value of the item changes.
Note: Notifier signal for property z.
参见 pos().