QtGui.QLayoutItem Class Reference

The QLayoutItem class provides an abstract item that a QLayout manipulates. More...

Inheritance diagram for QtGui.QLayoutItem:

Collaboration diagram for QtGui.QLayoutItem:

Public Member Functions
	QLayoutItem (IQLayoutItem copy)
	QLayoutItem (Qt.AlignmentFlag alignment=0)
virtual void	CreateProxy ()
new QSizePolicy.ControlType	ControlTypes ()
abstract Qt.Orientation	ExpandingDirections ()
virtual bool	HasHeightForWidth ()
virtual int	HeightForWidth (int arg1)
virtual void	Invalidate ()
abstract bool	IsEmpty ()
virtual QLayout	Layout ()
abstract QSize	MaximumSize ()
virtual int	MinimumHeightForWidth (int arg1)
abstract QSize	MinimumSize ()
abstract QSize	SizeHint ()
virtual QSpacerItem	SpacerItem ()
virtual QWidget	Widget ()
new void	Dispose ()
Public Member Functions inherited from QtGui.IQLayoutItem
new QSizePolicy.ControlType	ControlTypes ()
Qt.Orientation	ExpandingDirections ()
bool	HasHeightForWidth ()
int	HeightForWidth (int arg1)
void	Invalidate ()
bool	IsEmpty ()
QLayout	Layout ()
QSize	MaximumSize ()
int	MinimumHeightForWidth (int arg1)
QSize	MinimumSize ()
QSize	SizeHint ()
QSpacerItem	SpacerItem ()
QWidget	Widget ()

Protected Member Functions
	QLayoutItem (System.Type dummy)

Protected Attributes
SmokeInvocation	interceptor

Properties
new Qt.AlignmentFlag	Alignment [get, set]
abstract QRect	Geometry [get, set]
virtual System.IntPtr	SmokeObject [get, set]
new Qt.AlignmentFlag	Align [get, set]
Properties inherited from QtGui.IQLayoutItem
Qt.AlignmentFlag	Alignment [get, set]
QRect	Geometry [get, set]

Detailed Description

The QLayoutItem class provides an abstract item that a QLayout manipulates.

This is used by custom layouts.

Pure virtual functions are provided to return information about the layout, including, sizeHint(), minimumSize(), maximumSize() and expanding().

The layout's geometry can be set and retrieved with setGeometry() and geometry(), and its alignment with setAlignment() and alignment().

isEmpty() returns whether the layout item is empty. If the concrete item is a QWidget, it can be retrieved using widget(). Similarly for layout() and spacerItem().

Some layouts have width and height interdependencies. These can be expressed using hasHeightForWidth(), heightForWidth(), and minimumHeightForWidth(). For more explanation see the Qt Quarterly article Trading Height for Width.

See also QLayout.

Constructor & Destructor Documentation

QtGui.QLayoutItem.QLayoutItem ( System.Type  dummy )

protected

QtGui.QLayoutItem.QLayoutItem

(

IQLayoutItem

copy

)

Constructs a layout item with an alignment. Not all subclasses support alignment.

QtGui.QLayoutItem.QLayoutItem

(

Qt.AlignmentFlag

alignment = 0

)

Constructs a layout item with an alignment. Not all subclasses support alignment.

Member Function Documentation

new QSizePolicy.ControlType QtGui.QLayoutItem.ControlTypes

(

)

Returns the control type(s) for the layout item. For a QWidgetItem, the control type comes from the widget's size policy; for a QLayoutItem, the control types is derived from the layout's contents.

See also QSizePolicy::controlType().

virtual void QtGui.QLayoutItem.CreateProxy ( )

virtual

Reimplemented in QtGui.QWidgetItemV2, QtGui.QWidgetItem, and QtGui.QSpacerItem.

new void QtGui.QLayoutItem.Dispose

(

)

abstract Qt.Orientation QtGui.QLayoutItem.ExpandingDirections ( )

pure virtual

Returns whether this layout item can make use of more space than sizeHint(). A value of Qt::Vertical or Qt::Horizontal means that it wants to grow in only one dimension, whereas Qt::Vertical | Qt::Horizontal means that it wants to grow in both dimensions.

Implemented in QtGui.QWidgetItem, and QtGui.QSpacerItem.

virtual bool QtGui.QLayoutItem.HasHeightForWidth ( )

virtual

Returns true if this layout's preferred height depends on its width; otherwise returns false. The default implementation returns false.

Reimplement this function in layout managers that support height for width.

See also heightForWidth() and QWidget::heightForWidth().

Reimplemented in QtGui.QWidgetItem.

virtual int QtGui.QLayoutItem.HeightForWidth ( int  arg1 )

virtual

Returns the preferred height for this layout item, given the width w.

The default implementation returns -1, indicating that the preferred height is independent of the width of the item. Using the function hasHeightForWidth() will typically be much faster than calling this function and testing for -1.

Reimplement this function in layout managers that support height for width. A typical implementation will look like this:

int MyLayout::heightForWidth(int w) const

{

if (cache_dirty || cached_width != w) {

// not all C++ compilers support "mutable"

MyLayout that = (MyLayout)this;

int h = calculateHeightForWidth(w);

that->cached_hfw = h;

return h;

}

return cached_hfw;

}

Caching is strongly recommended; without it layout will take exponential time.

See also hasHeightForWidth().

Reimplemented in QtGui.QWidgetItemV2, and QtGui.QWidgetItem.

virtual void QtGui.QLayoutItem.Invalidate ( )

virtual

Invalidates any cached information in this layout item.

abstract bool QtGui.QLayoutItem.IsEmpty ( )

pure virtual

Implemented in subclasses to return whether this item is empty, i.e. whether it contains any widgets.

Implemented in QtGui.QWidgetItem, and QtGui.QSpacerItem.

virtual QLayout QtGui.QLayoutItem.Layout ( )

virtual

If this item is a QLayout, it is returned as a QLayout; otherwise 0 is returned. This function provides type-safe casting.

abstract QSize QtGui.QLayoutItem.MaximumSize ( )

pure virtual

Implemented in subclasses to return the maximum size of this item.

Implemented in QtGui.QWidgetItemV2, QtGui.QWidgetItem, and QtGui.QSpacerItem.

virtual int QtGui.QLayoutItem.MinimumHeightForWidth ( int  arg1 )

virtual

Returns the minimum height this widget needs for the given width, w. The default implementation simply returns heightForWidth(w).

abstract QSize QtGui.QLayoutItem.MinimumSize ( )

pure virtual

Implemented in subclasses to return the minimum size of this item.

Implemented in QtGui.QWidgetItemV2, QtGui.QWidgetItem, and QtGui.QSpacerItem.

abstract QSize QtGui.QLayoutItem.SizeHint ( )

pure virtual

Implemented in subclasses to return the preferred size of this item.

Implemented in QtGui.QWidgetItemV2, QtGui.QWidgetItem, and QtGui.QSpacerItem.

virtual QSpacerItem QtGui.QLayoutItem.SpacerItem ( )

virtual

If this item is a QSpacerItem, it is returned as a QSpacerItem; otherwise 0 is returned. This function provides type-safe casting.

Reimplemented in QtGui.QSpacerItem.

virtual QWidget QtGui.QLayoutItem.Widget ( )

virtual

If this item is a QWidget, it is returned as a QWidget; otherwise 0 is returned. This function provides type-safe casting.

Reimplemented in QtGui.QWidgetItem.

Member Data Documentation

SmokeInvocation QtGui.QLayoutItem.interceptor

protected

Property Documentation

new Qt.AlignmentFlag QtGui.QLayoutItem.Align

getsetprotected

new Qt.AlignmentFlag QtGui.QLayoutItem.Alignment

getset

Returns the alignment of this item.

Sets the alignment of this item to alignment.

Note: Item alignment is only supported by QLayoutItem subclasses where it would have a visual effect. Except for QSpacerItem, which provides blank space for layouts, all public Qt classes that inherit QLayoutItem support item alignment.

abstract QRect QtGui.QLayoutItem.Geometry

getset

Returns the rectangle covered by this layout item.

Implemented in subclasses to set this item's geometry to r.

virtual System.IntPtr QtGui.QLayoutItem.SmokeObject

getset