QSizePolicy ¶

概要 ¶

详细描述 ¶

The size policy of a widget is an expression of its willingness to be resized in various ways, and affects how the widget is treated by the layout engine . Each widget returns a QSizePolicy that describes the horizontal and vertical resizing policy it prefers when being laid out. You can change this for a specific widget by changing its sizePolicy 特性。

QSizePolicy contains two independent Policy values and two stretch factors; one describes the widgets’s horizontal size policy, and the other describes its vertical size policy. It also contains a flag to indicate whether the height and width of its preferred size are related.

The horizontal and vertical policies can be set in the constructor, and altered using the setHorizontalPolicy() and setVerticalPolicy() functions. The stretch factors can be set using the setHorizontalStretch() and setVerticalStretch() functions. The flag indicating whether the widget’s sizeHint() is width-dependent (such as a menu bar or a word-wrapping label) can be set using the setHeightForWidth() 函数。

The current size policies and stretch factors be retrieved using the horizontalPolicy() , verticalPolicy() , horizontalStretch() and verticalStretch() functions. Alternatively, use the transpose() function to swap the horizontal and vertical policies and stretches. The hasHeightForWidth() function returns the current status of the flag indicating the size hint dependencies.

使用 expandingDirections() function to determine whether the associated widget can make use of more space than its sizeHint() function indicates, as well as find out in which directions it can expand.

Finally, the QSizePolicy class provides operators comparing this size policy to a given policy, as well as a QVariant operator storing this QSizePolicy 作为 QVariant 对象。

另请参阅

QSize sizeHint() sizePolicy sizeHint()

class QSizePolicy ¶

QSizePolicy(horizontal, vertical[, type=DefaultType])

param type

ControlType

param vertical

Policy

param horizontal

Policy

构造 QSizePolicy object with Fixed as its horizontal and vertical policies.

The policies can be altered using the setHorizontalPolicy() and setVerticalPolicy() functions. Use the setHeightForWidth() function if the preferred height of the widget is dependent on the width of the widget (for example, a QLabel with line wrapping).

另请参阅

setHorizontalStretch() setVerticalStretch()

构造 QSizePolicy 对象采用给定 horizontal and vertical policies, and the specified control type .

使用 setHeightForWidth() if the preferred height of the widget is dependent on the width of the widget (for example, a QLabel with line wrapping).

另请参阅

setHorizontalStretch() setVerticalStretch() controlType()

PySide2.QtWidgets.QSizePolicy. PolicyFlag ¶

These flags are combined together to form the various Policy 值：

常量	描述
QSizePolicy.GrowFlag	The widget can grow beyond its size hint if necessary.
QSizePolicy.ExpandFlag	The widget should get as much space as possible.
QSizePolicy.ShrinkFlag	The widget can shrink below its size hint if necessary.
QSizePolicy.IgnoreFlag	The widget’s size hint is ignored. The widget will get as much space as possible.

另请参阅

Policy

PySide2.QtWidgets.QSizePolicy. Policy ¶

This enum describes the various per-dimension sizing types used when constructing a QSizePolicy .

常量	描述
QSizePolicy.Fixed	sizeHint() is the only acceptable alternative, so the widget can never grow or shrink (e.g. the vertical direction of a push button).
QSizePolicy.Minimum	The sizeHint() is minimal, and sufficient. The widget can be expanded, but there is no advantage to it being larger (e.g. the horizontal direction of a push button). It cannot be smaller than the size provided by sizeHint().
QSizePolicy.Maximum	The sizeHint() is a maximum. The widget can be shrunk any amount without detriment if other widgets need the space (e.g. a separator line). It cannot be larger than the size provided by sizeHint().
QSizePolicy.Preferred	The sizeHint() is best, but the widget can be shrunk and still be useful. The widget can be expanded, but there is no advantage to it being larger than sizeHint() (the default QWidget policy).
QSizePolicy.Expanding	The sizeHint() is a sensible size, but the widget can be shrunk and still be useful. The widget can make use of extra space, so it should get as much space as possible (e.g. the horizontal direction of a horizontal slider).
QSizePolicy.MinimumExpanding	The sizeHint() is minimal, and sufficient. The widget can make use of extra space, so it should get as much space as possible (e.g. the horizontal direction of a horizontal slider).
QSizePolicy.Ignored	The sizeHint() is ignored. The widget will get as much space as possible.

另请参阅

PolicyFlag setHorizontalPolicy() setVerticalPolicy()

PySide2.QtWidgets.QSizePolicy. ControlType ¶

此枚举指定 Widget 的不同类型，就布局交互而言：

常量	描述
QSizePolicy.DefaultType	The default type, when none is specified.
QSizePolicy.ButtonBox	A QDialogButtonBox 实例。
QSizePolicy.CheckBox	A QCheckBox 实例。
QSizePolicy.ComboBox	A QComboBox 实例。
QSizePolicy.Frame	A QFrame 实例。
QSizePolicy.GroupBox	A QGroupBox 实例。
QSizePolicy.Label	A QLabel 实例。
QSizePolicy.Line	A QFrame 实例与 HLine or VLine .
QSizePolicy.LineEdit	A QLineEdit 实例。
QSizePolicy.PushButton	A QPushButton 实例。
QSizePolicy.RadioButton	A QRadioButton 实例。
QSizePolicy.Slider	A QAbstractSlider 实例。
QSizePolicy.SpinBox	A QAbstractSpinBox 实例。
QSizePolicy.TabWidget	A QTabWidget 实例。
QSizePolicy.ToolButton	A QToolButton 实例。

另请参阅

setControlType() controlType()

PySide2.QtWidgets.QSizePolicy. controlType ( ) ¶

返回类型

ControlType

Returns the control type associated with the widget for which this size policy applies.

另请参阅

setControlType()

PySide2.QtWidgets.QSizePolicy. expandingDirections ( ) ¶

返回类型

Orientations

Returns whether a widget can make use of more space than the sizeHint() function indicates.

A value of Horizontal or Vertical means that the widget can grow horizontally or vertically (i.e., the horizontal or vertical policy is Expanding or MinimumExpanding ), whereas Horizontal | Vertical means that it can grow in both dimensions.

另请参阅

horizontalPolicy() verticalPolicy()

PySide2.QtWidgets.QSizePolicy. hasHeightForWidth ( ) ¶

返回类型

bool

返回 true if the widget’s preferred height depends on its width; otherwise returns false .

另请参阅

setHeightForWidth()

PySide2.QtWidgets.QSizePolicy. hasWidthForHeight ( ) ¶

返回类型

bool

返回 true if the widget’s width depends on its height; otherwise returns false .

另请参阅

setWidthForHeight()

PySide2.QtWidgets.QSizePolicy. horizontalPolicy ( ) ¶

返回类型

Policy

Returns the horizontal component of the size policy.

另请参阅

setHorizontalPolicy() verticalPolicy() horizontalStretch()

PySide2.QtWidgets.QSizePolicy. horizontalStretch ( ) ¶

返回类型

int

Returns the horizontal stretch factor of the size policy.

另请参阅

setHorizontalStretch() verticalStretch() horizontalPolicy()

PySide2.QtWidgets.QSizePolicy. __ne__ ( s ) ¶

参数

s – QSizePolicy

返回类型

bool

返回 true 若此策略不同于 other ；否则返回 false .

另请参阅

operator==()

PySide2.QtWidgets.QSizePolicy. __eq__ ( s ) ¶

参数

s – QSizePolicy

返回类型

bool

返回 true 若此策略等于 other ；否则返回 false .

另请参阅

operator!=()

PySide2.QtWidgets.QSizePolicy. retainSizeWhenHidden ( ) ¶

返回类型

bool

Returns whether the layout should retain the widget’s size when it is hidden. This is false 在默认情况下。

另请参阅

setRetainSizeWhenHidden()

PySide2.QtWidgets.QSizePolicy. setControlType ( type ) ¶

参数

type – ControlType

Sets the control type associated with the widget for which this size policy applies to type .

The control type specifies the type of the widget for which this size policy applies. It is used by some styles, notably QMacStyle, to insert proper spacing between widgets. For example, the macOS Aqua guidelines specify that push buttons should be separated by 12 pixels, whereas vertically stacked radio buttons only require 6 pixels.

另请参阅

controlType() layoutSpacing()

PySide2.QtWidgets.QSizePolicy. setHeightForWidth ( b ) ¶

参数

b – bool

Sets the flag determining whether the widget’s preferred height depends on its width, to dependent .

另请参阅

hasHeightForWidth() setWidthForHeight()

PySide2.QtWidgets.QSizePolicy. setHorizontalPolicy ( d ) ¶

参数

d – Policy

Sets the horizontal component to the given policy .

另请参阅

horizontalPolicy() setVerticalPolicy() setHorizontalStretch()

PySide2.QtWidgets.QSizePolicy. setHorizontalStretch ( stretchFactor ) ¶

参数

stretchFactor – int

Sets the horizontal stretch factor of the size policy to the given stretchFactor . stretchFactor must be in the range [0,255].

When two widgets are adjacent to each other in a horizontal layout, setting the horizontal stretch factor of the widget on the left to 2 and the factor of widget on the right to 1 will ensure that the widget on the left will always be twice the size of the one on the right.

另请参阅

horizontalStretch() setVerticalStretch() setHorizontalPolicy()

PySide2.QtWidgets.QSizePolicy. setRetainSizeWhenHidden ( retainSize ) ¶

参数

retainSize – bool

Sets whether a layout should retain the widget’s size when it is hidden. If retainSize is true , the layout will not be changed by hiding the widget.

另请参阅

retainSizeWhenHidden()

PySide2.QtWidgets.QSizePolicy. setVerticalPolicy ( d ) ¶

参数

d – Policy

Sets the vertical component to the given policy .

另请参阅

verticalPolicy() setHorizontalPolicy() setVerticalStretch()

PySide2.QtWidgets.QSizePolicy. setVerticalStretch ( stretchFactor ) ¶

参数

stretchFactor – int

Sets the vertical stretch factor of the size policy to the given stretchFactor . stretchFactor must be in the range [0,255].

When two widgets are adjacent to each other in a vertical layout, setting the vertical stretch factor of the widget on the top to 2 and the factor of widget on the bottom to 1 will ensure that the widget on the top will always be twice the size of the one on the bottom.

另请参阅

verticalStretch() setHorizontalStretch() setVerticalPolicy()

PySide2.QtWidgets.QSizePolicy. setWidthForHeight ( b ) ¶

参数

b – bool

Sets the flag determining whether the widget’s width depends on its height, to dependent .

This is only supported for QGraphicsLayout ‘s subclasses. It is not possible to have a layout with both height-for-width and width-for-height constraints at the same time.

另请参阅

hasWidthForHeight() setHeightForWidth()

PySide2.QtWidgets.QSizePolicy. transpose ( ) ¶

Swaps the horizontal and vertical policies and stretches.

另请参阅

transposed()

PySide2.QtWidgets.QSizePolicy. transposed ( ) ¶

返回类型

QSizePolicy

Returns a size policy object with the horizontal and vertical policies and stretches swapped.

另请参阅

transpose()

PySide2.QtWidgets.QSizePolicy. verticalPolicy ( ) ¶

返回类型

Policy

返回尺寸策略的垂直组件。

另请参阅

setVerticalPolicy() horizontalPolicy() verticalStretch()

PySide2.QtWidgets.QSizePolicy. verticalStretch ( ) ¶

返回类型

int

返回尺寸策略的垂直拉伸因子。

另请参阅

setVerticalStretch() horizontalStretch() verticalPolicy()