QQuickItem ¶

函数 ¶

虚函数 ¶

槽 ¶

信号 ¶

Custom Scene Graph Items ¶

All visual QML items are rendered using the scene graph, the default implementation of which is a low-level, high-performance rendering stack, closely tied to OpenGL. It is possible for subclasses of QQuickItem to add their own custom content into the scene graph by setting the ItemHasContents flag and reimplementing the updatePaintNode() 函数。

警告

It is crucial that OpenGL operations and interaction with the scene graph happens exclusively on the rendering thread, primarily during the updatePaintNode() call. The best rule of thumb is to only use classes with the “QSG” prefix inside the updatePaintNode() 函数。

注意

All classes with QSG prefix should be used solely on the scene graph’s rendering thread. See 场景图形和渲染 了解更多信息。

Graphics Resource Handling ¶

The preferred way to handle cleanup of graphics resources used in the scene graph, is to rely on the automatic cleanup of nodes. A QSGNode returned from updatePaintNode() is automatically deleted on the right thread at the right time. Trees of QSGNode instances are managed through the use of OwnedByParent , which is set by default. So, for the majority of custom scene graph items, no extra work will be required.

Implementations that store graphics resources outside the node tree, such as an item implementing textureProvider() , will need to take care in cleaning it up correctly depending on how the item is used in QML. The situations to handle are:

• The scene graph is invalidated; This can happen, for instance, if the window is hidden using hide() . If the item class implements a slot named invalidateSceneGraph() , this slot will be called on the rendering thread while the GUI thread is blocked. This is equivalent to connecting to sceneGraphInvalidated() . The OpenGL context of this item’s window will be bound when this slot is called. The only exception is if the native OpenGL has been destroyed outside Qt’s control, for instance through EGL_CONTEXT_LOST .

• The item is removed from the scene; If an item is taken out of the scene, for instance because it’s parent was set to null or an item in another window, the releaseResources() will be called on the GUI thread. scheduleRenderJob() should be used to schedule cleanup of rendering resources.

• The item is deleted; When the destructor if an item runs, it should delete any graphics resources it has. If neither of the two conditions above were already met, the item will be part of a window and it is possible to use scheduleRenderJob() to have them cleaned up. If an implementation ignores the call to releaseResources() , the item will in many cases no longer have access to a QQuickWindow and thus no means of scheduling cleanup.

When scheduling cleanup of graphics resources using scheduleRenderJob() , one should use either BeforeSynchronizingStage or AfterSynchronizingStage 。 synchronization stage is where the scene graph is changed as a result of changes to the QML tree. If cleanup is scheduled at any other time, it may result in other parts of the scene graph referencing the newly deleted objects as these parts have not been updated.

注意

使用 deleteLater() to clean up graphics resources is not recommended as this will run at an arbitrary time and it is unknown if there will be an OpenGL context bound when the deletion takes place.

Custom QPainter Items ¶

QQuickItem 提供子类 QQuickPaintedItem ，允许用户去渲染内容使用 QPainter .

警告

使用 QQuickPaintedItem uses an indirect 2D surface to render its content, either using software rasterization or using an OpenGL framebuffer object (FBO), so the rendering is a two-step operation. First rasterize the surface, then draw the surface. Using scene graph API directly is always significantly faster.

Behavior Animations ¶

If your Item uses the 行为 type to define animations for property changes, you should always use either setProperty() , QQmlProperty(), or write() when you need to modify those properties from C++. This ensures that the QML engine knows about the property change. Otherwise, the engine won’t be able to carry out your requested animation. Note that these functions incur a slight performance penalty. For more details, see Accessing Members of a QML Object Type from C++ .

另请参阅

QQuickWindow QQuickPaintedItem

class QQuickItem ( [ parent=None ] ) ¶

param parent

QQuickItem

构造 QQuickItem 采用给定 parent .

parent will be used as both the visual parent 和 QObject parent.

PySide2.QtQuick.QQuickItem. Flag ¶

This enum type is used to specify various item properties.

常量	描述
QQuickItem.ItemClipsChildrenToShape	Indicates this item should visually clip its children so that they are rendered only within the boundaries of this item.
QQuickItem.ItemAcceptsInputMethod	Indicates the item supports text input methods.
QQuickItem.ItemIsFocusScope	Indicates the item is a focus scope. See Qt Quick 中的键盘聚焦 了解更多信息。
QQuickItem.ItemHasContents	Indicates the item has visual content and should be rendered by the scene graph.
QQuickItem.ItemAcceptsDrops	Indicates the item accepts drag and drop events.

另请参阅

setFlag() setFlags() flags()

PySide2.QtQuick.QQuickItem. ItemChange ¶

Used in conjunction with itemChange() to notify the item about certain types of changes.

常量	描述
QQuickItem.ItemChildAddedChange	A child was added. ItemChangeData::item contains the added child.
QQuickItem.ItemChildRemovedChange	A child was removed. ItemChangeData::item contains the removed child.
QQuickItem.ItemSceneChange	The item was added to or removed from a scene. The QQuickWindow rendering the scene is specified in using ItemChangeData::window . The window parameter is null when the item is removed from a scene.
QQuickItem.ItemVisibleHasChanged	The item’s visibility has changed. ItemChangeData::boolValue contains the new visibility.
QQuickItem.ItemParentHasChanged	The item’s parent has changed. ItemChangeData::item contains the new parent.
QQuickItem.ItemOpacityHasChanged	The item’s opacity has changed. ItemChangeData::realValue contains the new opacity.
QQuickItem.ItemActiveFocusHasChanged	The item’s focus has changed. ItemChangeData::boolValue contains whether the item has focus or not.
QQuickItem.ItemRotationHasChanged	The item’s rotation has changed. ItemChangeData::realValue contains the new rotation.
QQuickItem.ItemDevicePixelRatioHasChanged	The device pixel ratio of the screen the item is on has changed. ItemChangedData::realValue contains the new device pixel ratio.
QQuickItem.ItemAntialiasingHasChanged	The antialiasing has changed. The current (boolean) value can be found in antialiasing .
QQuickItem.ItemEnabledHasChanged	The item’s enabled state has changed. ItemChangeData::boolValue contains the new enabled state. (since Qt 5.10)

PySide2.QtQuick.QQuickItem. TransformOrigin ¶

Controls the point about which simple transforms like scale apply.

常量	描述
QQuickItem.TopLeft	The top-left corner of the item.
QQuickItem.Top	The center point of the top of the item.
QQuickItem.TopRight	The top-right corner of the item.
QQuickItem.Left	The left most point of the vertical middle.
QQuickItem.Center	The center of the item.
QQuickItem.Right	The right most point of the vertical middle.
QQuickItem.BottomLeft	The bottom-left corner of the item.
QQuickItem.Bottom	The center point of the bottom of the item.
QQuickItem.BottomRight	The bottom-right corner of the item.

另请参阅

transformOrigin() setTransformOrigin()

PySide2.QtQuick.QQuickItem. acceptHoverEvents ( ) ¶

返回类型

bool

Returns whether hover events are accepted by this item.

默认值为 false。

If this is false, then the item will not receive any hover events through the hoverEnterEvent() , hoverMoveEvent() and hoverLeaveEvent() 函数。

另请参阅

setAcceptHoverEvents()

PySide2.QtQuick.QQuickItem. acceptTouchEvents ( ) ¶

返回类型

bool

Returns whether touch events are accepted by this item.

默认值为 false。

If this is false, then the item will not receive any touch events through the touchEvent() 函数。

另请参阅

setAcceptTouchEvents()

PySide2.QtQuick.QQuickItem. acceptedMouseButtons ( ) ¶

返回类型

MouseButtons

Returns the mouse buttons accepted by this item.

默认值为 NoButton ; that is, no mouse buttons are accepted.

If an item does not accept the mouse button for a particular mouse event, the mouse event will not be delivered to the item and will be delivered to the next item in the item hierarchy instead.

另请参阅

setAcceptedMouseButtons()

PySide2.QtQuick.QQuickItem. activeFocusChanged ( arg__1 ) ¶

参数

arg__1 – bool

PySide2.QtQuick.QQuickItem. activeFocusOnTab ( ) ¶

返回类型

bool

另请参阅

setActiveFocusOnTab()

PySide2.QtQuick.QQuickItem. activeFocusOnTabChanged ( arg__1 ) ¶

参数

arg__1 – bool

PySide2.QtQuick.QQuickItem. antialiasing ( ) ¶

返回类型

bool

另请参阅

setAntialiasing()

PySide2.QtQuick.QQuickItem. antialiasingChanged ( arg__1 ) ¶

参数

arg__1 – bool

PySide2.QtQuick.QQuickItem. baselineOffset ( ) ¶

返回类型

qreal

另请参阅

setBaselineOffset()

PySide2.QtQuick.QQuickItem. baselineOffsetChanged ( arg__1 ) ¶

参数

arg__1 – qreal

PySide2.QtQuick.QQuickItem. boundingRect ( ) ¶

返回类型

QRectF

PySide2.QtQuick.QQuickItem. childAt ( x , y ) ¶

参数

• x – qreal

• y – qreal

返回类型

QQuickItem

Returns the first visible child item found at point ( x , y ) within the coordinate system of this item.

返回 None if there is no such item.

PySide2.QtQuick.QQuickItem. childItems ( ) ¶

返回类型

Returns the children of this item.

PySide2.QtQuick.QQuickItem. childMouseEventFilter ( arg__1 , arg__2 ) ¶

参数

• arg__1 – QQuickItem

• arg__2 – QEvent

返回类型

bool

Reimplement this method to filter the mouse events that are received by this item’s children.

This method will only be called if filtersChildMouseEvents() 为 true。

Return true if the specified event should not be passed onto the specified child item , and false otherwise.

另请参阅

setFiltersChildMouseEvents()

PySide2.QtQuick.QQuickItem. childrenChanged ( ) ¶

PySide2.QtQuick.QQuickItem. childrenRect ( ) ¶

返回类型

QRectF

PySide2.QtQuick.QQuickItem. childrenRectChanged ( arg__1 ) ¶

参数

arg__1 – QRectF

PySide2.QtQuick.QQuickItem. clip ( ) ¶

返回类型

bool

另请参阅

setClip()

PySide2.QtQuick.QQuickItem. clipChanged ( arg__1 ) ¶

参数

arg__1 – bool

PySide2.QtQuick.QQuickItem. clipRect ( ) ¶

返回类型

QRectF

PySide2.QtQuick.QQuickItem. containmentMask ( ) ¶

返回类型

QObject

另请参阅

setContainmentMask()

PySide2.QtQuick.QQuickItem. containmentMaskChanged ( ) ¶

PySide2.QtQuick.QQuickItem. contains ( point ) ¶

参数

point – QPointF

返回类型

bool

Returns true if this item contains point , which is in local coordinates; returns false otherwise.

This function can be overwritten in order to handle point collisions in items with custom shapes. The default implementation checks if the point is inside the item’s bounding rect.

Note that this method is generally used to check whether the item is under the mouse cursor, and for that reason, the implementation of this function should be as light-weight as possible.

PySide2.QtQuick.QQuickItem. cursor ( ) ¶

返回类型

QCursor

Returns the cursor shape for this item.

The mouse cursor will assume this shape when it is over this item, unless an override cursor is set. See the list of predefined cursor 对象 了解有用形状范围。

If no cursor shape has been set this returns a cursor with the ArrowCursor shape, however another cursor shape may be displayed if an overlapping item has a valid cursor.

另请参阅

setCursor() unsetCursor()

PySide2.QtQuick.QQuickItem. dragEnterEvent ( arg__1 ) ¶

参数

arg__1 – QDragEnterEvent

This event handler can be reimplemented in a subclass to receive drag-enter events for an item. The event information is provided by the event 参数。

Drag and drop events are only provided if the ItemAcceptsDrops flag has been set for this item.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

另请参阅

Drag 拖放

PySide2.QtQuick.QQuickItem. dragLeaveEvent ( arg__1 ) ¶

参数

arg__1 – QDragLeaveEvent

This event handler can be reimplemented in a subclass to receive drag-leave events for an item. The event information is provided by the event 参数。

Drag and drop events are only provided if the ItemAcceptsDrops flag has been set for this item.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

另请参阅

Drag 拖放

PySide2.QtQuick.QQuickItem. dragMoveEvent ( arg__1 ) ¶

参数

arg__1 – QDragMoveEvent

This event handler can be reimplemented in a subclass to receive drag-move events for an item. The event information is provided by the event 参数。

Drag and drop events are only provided if the ItemAcceptsDrops flag has been set for this item.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

另请参阅

Drag 拖放

PySide2.QtQuick.QQuickItem. dropEvent ( arg__1 ) ¶

参数

arg__1 – QDropEvent

This event handler can be reimplemented in a subclass to receive drop events for an item. The event information is provided by the event 参数。

Drag and drop events are only provided if the ItemAcceptsDrops flag has been set for this item.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

另请参阅

Drag 拖放

PySide2.QtQuick.QQuickItem. enabledChanged ( ) ¶

PySide2.QtQuick.QQuickItem. filtersChildMouseEvents ( ) ¶

返回类型

bool

Returns whether mouse and touch events of this item’s children should be filtered through this item.

另请参阅

setFiltersChildMouseEvents() childMouseEventFilter()

PySide2.QtQuick.QQuickItem. flags ( ) ¶

返回类型

标志

Returns the item flags for this item.

另请参阅

setFlags() setFlag()

PySide2.QtQuick.QQuickItem. focusChanged ( arg__1 ) ¶

参数

arg__1 – bool

PySide2.QtQuick.QQuickItem. focusInEvent ( arg__1 ) ¶

参数

arg__1 – QFocusEvent

This event handler can be reimplemented in a subclass to receive focus-in events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

If you do reimplement this function, you should call the base class implementation.

PySide2.QtQuick.QQuickItem. focusOutEvent ( arg__1 ) ¶

参数

arg__1 – QFocusEvent

This event handler can be reimplemented in a subclass to receive focus-out events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. forceActiveFocus ( ) ¶

Forces active focus on the item.

This method sets focus on the item and ensures that all ancestor FocusScope objects in the object hierarchy are also given focus .

The reason for the focus change will be OtherFocusReason . Use the overloaded method to specify the focus reason to enable better handling of the focus change.

另请参阅

activeFocus

PySide2.QtQuick.QQuickItem. forceActiveFocus ( reason ) ¶

参数

reason – FocusReason

这是重载函数。

Forces active focus on the item with the given reason .

This method sets focus on the item and ensures that all ancestor FocusScope objects in the object hierarchy are also given focus .

另请参阅

activeFocus FocusReason

PySide2.QtQuick.QQuickItem. geometryChanged ( newGeometry , oldGeometry ) ¶

参数

• newGeometry – QRectF

• oldGeometry – QRectF

This function is called to handle this item’s changes in geometry from oldGeometry to newGeometry . If the two geometries are the same, it doesn’t do anything.

Derived classes must call the base class method within their implementation.

PySide2.QtQuick.QQuickItem. grabMouse ( ) ¶

抓取鼠标输入。

This item will receive all mouse events until ungrabMouse() is called. Usually this function should not be called, since accepting for example a mouse press event makes sure that the following events are delivered to the item. If an item wants to take over mouse events from the current receiver, it needs to call this function.

警告

This function should be used with caution.

PySide2.QtQuick.QQuickItem. grabToImage ( callback [ , targetSize=QSize() ] ) ¶

参数

• callback – QJSValue

• targetSize – QSize

返回类型

bool

Only visible from QML.

PySide2.QtQuick.QQuickItem. grabToImage ( [ targetSize=QSize() ] ) ¶

参数

targetSize – QSize

返回类型

QSharedPointer

Grabs the item into an in-memory image.

The grab happens asynchronously and the signal ready() is emitted when the grab has been completed.

使用 targetSize to specify the size of the target image. By default, the result will have the same size as item.

If the grab could not be initiated, the function returns null .

注意

This function will render the item to an offscreen surface and copy that surface from the GPU’s memory into the CPU’s memory, which can be quite costly. For “live” preview, use layers or ShaderEffectSource .

另请参阅

grabWindow()

PySide2.QtQuick.QQuickItem. grabTouchPoints ( ids ) ¶

参数

ids –

Grabs the touch points specified by ids .

These touch points will be owned by the item until they are released. Alternatively, the grab can be stolen by a filtering item like Flickable. Use setKeepTouchGrab() to prevent the grab from being stolen.

另请参阅

ungrabTouchPoints() setKeepTouchGrab()

PySide2.QtQuick.QQuickItem. hasActiveFocus ( ) ¶

返回类型

bool

PySide2.QtQuick.QQuickItem. hasFocus ( ) ¶

返回类型

bool

PySide2.QtQuick.QQuickItem. height ( ) ¶

返回类型

qreal

另请参阅

setHeight()

PySide2.QtQuick.QQuickItem. heightChanged ( ) ¶

PySide2.QtQuick.QQuickItem. heightValid ( ) ¶

返回类型

bool

Returns whether the height property has been set explicitly.

PySide2.QtQuick.QQuickItem. hoverEnterEvent ( event ) ¶

参数

event – QHoverEvent

This event handler can be reimplemented in a subclass to receive hover-enter events for an item. The event information is provided by the event 参数。

Hover events are only provided if acceptHoverEvents() 为 true。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. hoverLeaveEvent ( event ) ¶

参数

event – QHoverEvent

This event handler can be reimplemented in a subclass to receive hover-leave events for an item. The event information is provided by the event 参数。

Hover events are only provided if acceptHoverEvents() 为 true。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. hoverMoveEvent ( event ) ¶

参数

event – QHoverEvent

This event handler can be reimplemented in a subclass to receive hover-move events for an item. The event information is provided by the event 参数。

Hover events are only provided if acceptHoverEvents() 为 true。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. implicitHeight ( ) ¶

返回类型

qreal

另请参阅

setImplicitHeight()

PySide2.QtQuick.QQuickItem. implicitHeightChanged ( ) ¶

PySide2.QtQuick.QQuickItem. implicitWidth ( ) ¶

返回类型

qreal

Returns the width of the item that is implied by other properties that determine the content.

另请参阅

setImplicitWidth()

PySide2.QtQuick.QQuickItem. implicitWidthChanged ( ) ¶

PySide2.QtQuick.QQuickItem. inputMethodEvent ( arg__1 ) ¶

参数

arg__1 – QInputMethodEvent

This event handler can be reimplemented in a subclass to receive input method events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. inputMethodQuery ( query ) ¶

参数

query – InputMethodQuery

返回类型

object

This method is only relevant for input items.

If this item is an input item, this method should be reimplemented to return the relevant input method flags for the given query .

另请参阅

inputMethodQuery()

PySide2.QtQuick.QQuickItem. isAncestorOf ( child ) ¶

参数

child – QQuickItem

返回类型

bool

返回 true if this item is an ancestor of child (i.e., if this item is child ‘s parent, or one of child ‘s parent’s ancestors).

另请参阅

parentItem()

PySide2.QtQuick.QQuickItem. isComponentComplete ( ) ¶

返回类型

bool

Returns true if construction of the QML component is complete; otherwise returns false.

It is often desirable to delay some processing until the component is completed.

另请参阅

componentComplete()

PySide2.QtQuick.QQuickItem. isEnabled ( ) ¶

返回类型

bool

PySide2.QtQuick.QQuickItem. isFocusScope ( ) ¶

返回类型

bool

Returns true if this item is a focus scope, and false otherwise.

PySide2.QtQuick.QQuickItem. isTextureProvider ( ) ¶

返回类型

bool

Returns true if this item is a texture provider. The default implementation returns false.

This function can be called from any thread.

PySide2.QtQuick.QQuickItem. isUnderMouse ( ) ¶

返回类型

bool

PySide2.QtQuick.QQuickItem. isVisible ( ) ¶

返回类型

bool

PySide2.QtQuick.QQuickItem. itemTransform ( arg__1 ) ¶

参数

arg__1 – QQuickItem

返回类型

PyTuple

PySide2.QtQuick.QQuickItem. keepMouseGrab ( ) ¶

返回类型

bool

Returns whether mouse input should exclusively remain with this item.

另请参阅

setKeepMouseGrab()

PySide2.QtQuick.QQuickItem. keepTouchGrab ( ) ¶

返回类型

bool

Returns whether the touch points grabbed by this item should exclusively remain with this item.

另请参阅

setKeepTouchGrab() keepMouseGrab()

PySide2.QtQuick.QQuickItem. keyPressEvent ( event ) ¶

参数

event – QKeyEvent

This event handler can be reimplemented in a subclass to receive key press events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. keyReleaseEvent ( event ) ¶

参数

event – QKeyEvent

This event handler can be reimplemented in a subclass to receive key release events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. mapFromGlobal ( point ) ¶

参数

point – QPointF

返回类型

QPointF

Maps the given point in the global screen coordinate system to the equivalent point within this item’s coordinate system, and returns the mapped coordinate.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

For example, this may be helpful to add a popup to a Qt Quick component.

注意

Window positioning is done by the window manager and this value is treated only as a hint. So, the resulting window position may differ from what is expected.

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapFromItem ( item , point ) ¶

参数

• item – QQuickItem

• point – QPointF

返回类型

QPointF

Maps the given point in item ‘s coordinate system to the equivalent point within this item’s coordinate system, and returns the mapped coordinate.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

若 item is 0, this maps point from the coordinate system of the scene.

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapFromScene ( point ) ¶

参数

point – QPointF

返回类型

QPointF

Maps the given point in the scene’s coordinate system to the equivalent point within this item’s coordinate system, and returns the mapped coordinate.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapRectFromItem ( item , rect ) ¶

参数

• item – QQuickItem

• rect – QRectF

返回类型

QRectF

Maps the given rect in item ‘s coordinate system to the equivalent rectangular area within this item’s coordinate system, and returns the mapped rectangle value.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

若 item is 0, this maps rect from the coordinate system of the scene.

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapRectFromScene ( rect ) ¶

参数

rect – QRectF

返回类型

QRectF

Maps the given rect in the scene’s coordinate system to the equivalent rectangular area within this item’s coordinate system, and returns the mapped rectangle value.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapRectToItem ( item , rect ) ¶

参数

• item – QQuickItem

• rect – QRectF

返回类型

QRectF

Maps the given rect in this item’s coordinate system to the equivalent rectangular area within item ‘s coordinate system, and returns the mapped rectangle value.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

若 item is 0, this maps rect to the coordinate system of the scene.

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapRectToScene ( rect ) ¶

参数

rect – QRectF

返回类型

QRectF

Maps the given rect in this item’s coordinate system to the equivalent rectangular area within the scene’s coordinate system, and returns the mapped rectangle value.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapToGlobal ( point ) ¶

参数

point – QPointF

返回类型

QPointF

Maps the given point in this item’s coordinate system to the equivalent point within global screen coordinate system, and returns the mapped coordinate.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

For example, this may be helpful to add a popup to a Qt Quick component.

注意

Window positioning is done by the window manager and this value is treated only as a hint. So, the resulting window position may differ from what is expected.

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapToItem ( item , point ) ¶

参数

• item – QQuickItem

• point – QPointF

返回类型

QPointF

Maps the given point in this item’s coordinate system to the equivalent point within item ‘s coordinate system, and returns the mapped coordinate.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

若 item is 0, this maps point to the coordinate system of the scene.

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mapToScene ( point ) ¶

参数

point – QPointF

返回类型

QPointF

Maps the given point in this item’s coordinate system to the equivalent point within the scene’s coordinate system, and returns the mapped coordinate.

The following properties of the item are used in the mapping: x , y , scale , rotation , transformOrigin ，和 transform .

另请参阅

Concepts - Visual Coordinates in Qt Quick

PySide2.QtQuick.QQuickItem. mouseDoubleClickEvent ( event ) ¶

参数

event – QMouseEvent

This event handler can be reimplemented in a subclass to receive mouse double-click events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. mouseMoveEvent ( event ) ¶

参数

event – QMouseEvent

This event handler can be reimplemented in a subclass to receive mouse move events for an item. The event information is provided by the event 参数。

In order to receive mouse movement events, the preceding mouse press event must be accepted (by overriding mousePressEvent() , for example) and acceptedMouseButtons() must return the relevant mouse button.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. mousePressEvent ( event ) ¶

参数

event – QMouseEvent

This event handler can be reimplemented in a subclass to receive mouse press events for an item. The event information is provided by the event 参数。

In order to receive mouse press events, acceptedMouseButtons() must return the relevant mouse button.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. mouseReleaseEvent ( event ) ¶

参数

event – QMouseEvent

This event handler can be reimplemented in a subclass to receive mouse release events for an item. The event information is provided by the event 参数。

In order to receive mouse release events, the preceding mouse press event must be accepted (by overriding mousePressEvent() , for example) and acceptedMouseButtons() must return the relevant mouse button.

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. mouseUngrabEvent ( ) ¶

This event handler can be reimplemented in a subclass to be notified when a mouse ungrab event has occurred on this item.

PySide2.QtQuick.QQuickItem. nextItemInFocusChain ( [ forward=true ] ) ¶

参数

forward – bool

返回类型

QQuickItem

Returns the item in the focus chain which is next to this item. If forward is true , or not supplied, it is the next item in the forwards direction. If forward is false , it is the next item in the backwards direction.

PySide2.QtQuick.QQuickItem. opacity ( ) ¶

返回类型

qreal

另请参阅

setOpacity()

PySide2.QtQuick.QQuickItem. opacityChanged ( ) ¶

PySide2.QtQuick.QQuickItem. parentChanged ( arg__1 ) ¶

参数

arg__1 – QQuickItem

PySide2.QtQuick.QQuickItem. parentItem ( ) ¶

返回类型

QQuickItem

另请参阅

setParentItem()

PySide2.QtQuick.QQuickItem. polish ( ) ¶

Schedules a polish event for this item.

When the scene graph processes the request, it will call updatePolish() on this item.

另请参阅

updatePolish() qIsPolishScheduled()

PySide2.QtQuick.QQuickItem. position ( ) ¶

返回类型

QPointF

PySide2.QtQuick.QQuickItem. releaseResources ( ) ¶

This function is called when an item should release graphics resources which are not already managed by the nodes returned from updatePaintNode() .

This happens when the item is about to be removed from the window it was previously rendering to. The item is guaranteed to have a window when the function is called.

The function is called on the GUI thread and the state of the rendering thread, when it is used, is unknown. Objects should not be deleted directly, but instead scheduled for cleanup using scheduleRenderJob() .

另请参阅

图形 Resource Handling

PySide2.QtQuick.QQuickItem. resetAntialiasing ( ) ¶

PySide2.QtQuick.QQuickItem. resetHeight ( ) ¶

PySide2.QtQuick.QQuickItem. resetWidth ( ) ¶

PySide2.QtQuick.QQuickItem. rotation ( ) ¶

返回类型

qreal

另请参阅

setRotation()

PySide2.QtQuick.QQuickItem. rotationChanged ( ) ¶

PySide2.QtQuick.QQuickItem. scale ( ) ¶

返回类型

qreal

另请参阅

setScale()

PySide2.QtQuick.QQuickItem. scaleChanged ( ) ¶

PySide2.QtQuick.QQuickItem. scopedFocusItem ( ) ¶

返回类型

QQuickItem

If this item is a focus scope, this returns the item in its focus chain that currently has focus.

返回 None if this item is not a focus scope.

PySide2.QtQuick.QQuickItem. setAcceptHoverEvents ( enabled ) ¶

参数

enabled – bool

若 enabled is true, this sets the item to accept hover events; otherwise, hover events are not accepted by this item.

另请参阅

acceptHoverEvents()

PySide2.QtQuick.QQuickItem. setAcceptTouchEvents ( accept ) ¶

参数

accept – bool

若 enabled is true, this sets the item to accept touch events; otherwise, touch events are not accepted by this item.

另请参阅

acceptTouchEvents()

PySide2.QtQuick.QQuickItem. setAcceptedMouseButtons ( buttons ) ¶

参数

buttons – MouseButtons

Sets the mouse buttons accepted by this item to buttons .

另请参阅

acceptedMouseButtons()

PySide2.QtQuick.QQuickItem. setActiveFocusOnTab ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

activeFocusOnTab()

PySide2.QtQuick.QQuickItem. setAntialiasing ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

antialiasing()

PySide2.QtQuick.QQuickItem. setBaselineOffset ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

baselineOffset()

PySide2.QtQuick.QQuickItem. setClip ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

clip()

PySide2.QtQuick.QQuickItem. setContainmentMask ( mask ) ¶

参数

mask – QObject

另请参阅

containmentMask()

PySide2.QtQuick.QQuickItem. setCursor ( cursor ) ¶

参数

cursor – QCursor

设置 cursor shape for this item.

另请参阅

cursor() unsetCursor()

PySide2.QtQuick.QQuickItem. setEnabled ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

isEnabled()

PySide2.QtQuick.QQuickItem. setFiltersChildMouseEvents ( filter ) ¶

参数

filter – bool

Sets whether mouse and touch events of this item’s children should be filtered through this item.

若 filter is true, childMouseEventFilter() will be called when a mouse event is triggered for a child item.

另请参阅

filtersChildMouseEvents()

PySide2.QtQuick.QQuickItem. setFlag ( flag [ , enabled=true ] ) ¶

参数

• flag – Flag

• enabled – bool

Enables the specified flag for this item if enabled is true; if enabled is false, the flag is disabled.

These provide various hints for the item; for example, the ItemClipsChildrenToShape flag indicates that all children of this item should be clipped to fit within the item area.

PySide2.QtQuick.QQuickItem. setFlags ( flags ) ¶

参数

flags – 标志

Enables the specified flags for this item.

另请参阅

flags() setFlag()

PySide2.QtQuick.QQuickItem. setFocus ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

hasFocus()

PySide2.QtQuick.QQuickItem. setFocus ( focus , reason ) ¶

参数

• focus – bool

• reason – FocusReason

PySide2.QtQuick.QQuickItem. setHeight ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

height()

PySide2.QtQuick.QQuickItem. setImplicitHeight ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

implicitHeight()

PySide2.QtQuick.QQuickItem. setImplicitSize ( arg__1 , arg__2 ) ¶

参数

• arg__1 – qreal

• arg__2 – qreal

PySide2.QtQuick.QQuickItem. setImplicitWidth ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

implicitWidth()

PySide2.QtQuick.QQuickItem. setKeepMouseGrab ( arg__1 ) ¶

参数

arg__1 – bool

Sets whether the mouse input should remain exclusively with this item.

This is useful for items that wish to grab and keep mouse interaction following a predefined gesture. For example, an item that is interested in horizontal mouse movement may set keepMouseGrab to true once a threshold has been exceeded. Once keepMouseGrab has been set to true, filtering items will not react to mouse events.

若 keep is false, a filtering item may steal the grab. For example, Flickable may attempt to steal a mouse grab if it detects that the user has begun to move the viewport.

另请参阅

keepMouseGrab()

PySide2.QtQuick.QQuickItem. setKeepTouchGrab ( arg__1 ) ¶

参数

arg__1 – bool

Sets whether the touch points grabbed by this item should remain exclusively with this item.

This is useful for items that wish to grab and keep specific touch points following a predefined gesture. For example, an item that is interested in horizontal touch point movement may set to true once a threshold has been exceeded. Once has been set to true, filtering items will not react to the relevant touch points.

若 keep is false, a filtering item may steal the grab. For example, Flickable may attempt to steal a touch point grab if it detects that the user has begun to move the viewport.

另请参阅

keepTouchGrab() setKeepMouseGrab()

PySide2.QtQuick.QQuickItem. setOpacity ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

opacity()

PySide2.QtQuick.QQuickItem. setParentItem ( parent ) ¶

参数

parent – QQuickItem

另请参阅

parentItem()

PySide2.QtQuick.QQuickItem. setPosition ( arg__1 ) ¶

参数

arg__1 – QPointF

PySide2.QtQuick.QQuickItem. setRotation ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

rotation()

PySide2.QtQuick.QQuickItem. setScale ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

scale()

PySide2.QtQuick.QQuickItem. setSize ( size ) ¶

参数

size – QSizeF

Sets the size of the item to size .

另请参阅

size setWidth setHeight

PySide2.QtQuick.QQuickItem. setSmooth ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

smooth()

PySide2.QtQuick.QQuickItem. setState ( arg__1 ) ¶

参数

arg__1 – unicode

另请参阅

state()

PySide2.QtQuick.QQuickItem. setTransformOrigin ( arg__1 ) ¶

参数

arg__1 – TransformOrigin

另请参阅

transformOrigin()

PySide2.QtQuick.QQuickItem. setTransformOriginPoint ( arg__1 ) ¶

参数

arg__1 – QPointF

PySide2.QtQuick.QQuickItem. setVisible ( arg__1 ) ¶

参数

arg__1 – bool

另请参阅

isVisible()

PySide2.QtQuick.QQuickItem. setWidth ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

width()

PySide2.QtQuick.QQuickItem. setX ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

x()

PySide2.QtQuick.QQuickItem. setY ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

y()

PySide2.QtQuick.QQuickItem. setZ ( arg__1 ) ¶

参数

arg__1 – qreal

另请参阅

z()

PySide2.QtQuick.QQuickItem. size ( ) ¶

返回类型

QSizeF

Returns the size of the item.

另请参阅

setSize width height

PySide2.QtQuick.QQuickItem. smooth ( ) ¶

返回类型

bool

另请参阅

setSmooth()

PySide2.QtQuick.QQuickItem. smoothChanged ( arg__1 ) ¶

参数

arg__1 – bool

PySide2.QtQuick.QQuickItem. stackAfter ( arg__1 ) ¶

参数

arg__1 – QQuickItem

Moves the specified sibling item to the index after this item within the list of children. The order of children affects both the visual stacking order and tab focus navigation order.

Assuming the z values of both items are the same, this will cause sibling to be rendered below this item.

If both items have activeFocusOnTab 设为 true , this will also cause the tab focus order to change, with sibling receiving focus before this item.

给定 sibling must be a sibling of this item; that is, they must have the same immediate parent .

另请参阅

概念 - Qt Quick 中的可视父级

PySide2.QtQuick.QQuickItem. stackBefore ( arg__1 ) ¶

参数

arg__1 – QQuickItem

Moves the specified sibling item to the index before this item within the list of children. The order of children affects both the visual stacking order and tab focus navigation order.

Assuming the z values of both items are the same, this will cause sibling to be rendered above this item.

If both items have activeFocusOnTab 设为 true , this will also cause the tab focus order to change, with sibling receiving focus after this item.

给定 sibling must be a sibling of this item; that is, they must have the same immediate parent .

另请参阅

概念 - Qt Quick 中的可视父级

PySide2.QtQuick.QQuickItem. state ( ) ¶

返回类型

unicode

另请参阅

setState()

PySide2.QtQuick.QQuickItem. stateChanged ( arg__1 ) ¶

参数

arg__1 – unicode

PySide2.QtQuick.QQuickItem. textureProvider ( ) ¶

返回类型

QSGTextureProvider

Returns the texture provider for an item. The default implementation returns None .

This function may only be called on the rendering thread.

PySide2.QtQuick.QQuickItem. touchEvent ( event ) ¶

参数

event – QTouchEvent

This event handler can be reimplemented in a subclass to receive touch events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. touchUngrabEvent ( ) ¶

This event handler can be reimplemented in a subclass to be notified when a touch ungrab event has occurred on this item.

PySide2.QtQuick.QQuickItem. transformOrigin ( ) ¶

返回类型

TransformOrigin

另请参阅

setTransformOrigin()

PySide2.QtQuick.QQuickItem. transformOriginChanged ( arg__1 ) ¶

参数

arg__1 – TransformOrigin

PySide2.QtQuick.QQuickItem. transformOriginPoint ( ) ¶

返回类型

QPointF

PySide2.QtQuick.QQuickItem. ungrabMouse ( ) ¶

Releases the mouse grab following a call to grabMouse() .

Note that this function should only be called when the item wants to stop handling further events. There is no need to call this function after a release or cancel event since no future events will be received in any case. No move or release events will be delivered after this function was called.

PySide2.QtQuick.QQuickItem. ungrabTouchPoints ( ) ¶

Ungrabs the touch points owned by this item.

注意

there is hardly any reason to call this function. It should only be called when an item does not want to receive any further events, so no move or release events will be delivered after calling this function.

另请参阅

grabTouchPoints()

PySide2.QtQuick.QQuickItem. unsetCursor ( ) ¶

Clears the cursor shape for this item.

另请参阅

cursor() setCursor()

PySide2.QtQuick.QQuickItem. update ( ) ¶

Schedules a call to updatePaintNode() for this item.

The call to updatePaintNode() will always happen if the item is showing in a QQuickWindow .

Only items which specify ItemHasContents are allowed to call .

PySide2.QtQuick.QQuickItem. updateInputMethod ( [ queries=Qt.ImQueryInput ] ) ¶

参数

queries – InputMethodQueries

Notify input method on updated query values if needed. queries indicates the changed attributes.

PySide2.QtQuick.QQuickItem. updatePaintNode ( arg__1 , arg__2 ) ¶

参数

• arg__1 – QSGNode

• arg__2 – UpdatePaintNodeData

返回类型

QSGNode

Called on the render thread when it is time to sync the state of the item with the scene graph.

The function is called as a result of update() , if the user has set the ItemHasContents flag on the item.

The function should return the root of the scene graph subtree for this item. Most implementations will return a single QSGGeometryNode containing the visual representation of this item. oldNode is the node that was returned the last time the function was called. updatePaintNodeData provides a pointer to the QSGTransformNode associated with this QQuickItem .

QSGNode *MyItem::updatePaintNode(QSGNode *node, UpdatePaintNodeData *)
{
    QSGSimpleRectNode *n = static_cast<QSGSimpleRectNode *>(node);
    if (!n) {
        n = new QSGSimpleRectNode();
        n->setColor(Qt::red);
    }
    n->setRect(boundingRect());
    return n;
}
												

The main thread is blocked while this function is executed so it is safe to read values from the QQuickItem instance and other objects in the main thread.

If no call to result in actual scene graph changes, like markDirty() or adding and removing nodes, then the underlying implementation may decide to not render the scene again as the visual outcome is identical.

警告

It is crucial that OpenGL operations and interaction with the scene graph happens exclusively on the render thread, primarily during the call. The best rule of thumb is to only use classes with the “QSG” prefix inside the function.

警告

This function is called on the render thread. This means any QObjects or thread local storage that is created will have affinity to the render thread, so apply caution when doing anything other than rendering in this function. Similarly for signals, these will be emitted on the render thread and will thus often be delivered via queued connections.

注意

All classes with QSG prefix should be used solely on the scene graph’s rendering thread. See 场景图形和渲染 了解更多信息。

另请参阅

QSGMaterial QSGSimpleMaterial QSGGeometryNode QSGGeometry QSGFlatColorMaterial QSGTextureMaterial markDirty() 图形 Resource Handling

PySide2.QtQuick.QQuickItem. updatePolish ( ) ¶

This function should perform any layout as required for this item.

当 polish() is called, the scene graph schedules a polish event for this item. When the scene graph is ready to render this item, it calls to do any item layout as required before it renders the next frame.

PySide2.QtQuick.QQuickItem. visibleChanged ( ) ¶

PySide2.QtQuick.QQuickItem. visibleChildrenChanged ( ) ¶

PySide2.QtQuick.QQuickItem. wheelEvent ( event ) ¶

参数

event – QWheelEvent

This event handler can be reimplemented in a subclass to receive wheel events for an item. The event information is provided by the event 参数。

The event is accepted by default, so it is not necessary to explicitly accept the event if you reimplement this function. If you don’t accept the event, call event->ignore() .

PySide2.QtQuick.QQuickItem. width ( ) ¶

返回类型

qreal

另请参阅

setWidth()

PySide2.QtQuick.QQuickItem. widthChanged ( ) ¶

PySide2.QtQuick.QQuickItem. widthValid ( ) ¶

返回类型

bool

Returns whether the width property has been set explicitly.

PySide2.QtQuick.QQuickItem. window ( ) ¶

返回类型

QQuickWindow

Returns the window in which this item is rendered.

The item does not have a window until it has been assigned into a scene. The windowChanged() signal provides a notification both when the item is entered into a scene and when it is removed from a scene.

PySide2.QtQuick.QQuickItem. windowChanged ( window ) ¶

参数

window – QQuickWindow

PySide2.QtQuick.QQuickItem. windowDeactivateEvent ( ) ¶

PySide2.QtQuick.QQuickItem. x ( ) ¶

返回类型

qreal

另请参阅

setX()

PySide2.QtQuick.QQuickItem. xChanged ( ) ¶

PySide2.QtQuick.QQuickItem. y ( ) ¶

返回类型

qreal

另请参阅

setY()

PySide2.QtQuick.QQuickItem. yChanged ( ) ¶

PySide2.QtQuick.QQuickItem. z ( ) ¶

返回类型

qreal

另请参阅

setZ()

PySide2.QtQuick.QQuickItem. zChanged ( ) ¶