LayoutHelper Class

Definition

Namespace:Avalonia.Layout

Assembly:Avalonia.Base

Package:Avalonia

Source:LayoutHelper.cs

Provides helper methods needed for layout.

public class LayoutHelper

Inheritance: object -> LayoutHelper

Methods

Name	Description
ApplyLayoutConstraints	Calculates a control's size based on its Avalonia.Layout.Layoutable.Width, Avalonia.Layout.Layoutable.Height, Avalonia.Layout.Layoutable.MinWidth, Avalonia.Layout.Layoutable.MaxWidth, Avalonia.Layout.Layoutable.MinHeight and Avalonia.Layout.Layoutable.MaxHeight.
ArrangeChild (2 overloads)	No summary available.
GetLayoutScale	Obtains layout scale of the given control.
InvalidateSelfAndChildrenMeasure	Invalidates measure for given control and all visual children recursively.
MeasureChild (2 overloads)	No summary available.
RoundLayoutPoint	No summary available.
RoundLayoutSizeUp	Rounds a size to integer values for layout purposes, compensating for high DPI screen coordinates by rounding the size up to the nearest pixel.
RoundLayoutThickness	Rounds a thickness to integer values for layout purposes, compensating for high DPI screen coordinates.
RoundLayoutValue	Calculates the value to be used for layout rounding at high DPI by rounding the value up or down to the nearest pixel.
RoundLayoutValueUp	Calculates the value to be used for layout rounding at high DPI by rounding the value up to the nearest pixel.

ApplyLayoutConstraints Method

Calculates a control's size based on its Avalonia.Layout.Layoutable.Width, Avalonia.Layout.Layoutable.Height, Avalonia.Layout.Layoutable.MinWidth, Avalonia.Layout.Layoutable.MaxWidth, Avalonia.Layout.Layoutable.MinHeight and Avalonia.Layout.Layoutable.MaxHeight.

public Avalonia.Size ApplyLayoutConstraints(Avalonia.Layout.Layoutable control, Avalonia.Size constraints)

Parameters

control Avalonia.Layout.Layoutable

The control.

constraints Avalonia.Size

The space available for the control.

Returns

Avalonia.Size

The control's size.

ArrangeChild overloads

ArrangeChild Method

public Avalonia.Size ArrangeChild(Avalonia.Layout.Layoutable child, Avalonia.Size availableSize, Avalonia.Thickness padding)

Parameters

child Avalonia.Layout.Layoutable

availableSize Avalonia.Size

padding Avalonia.Thickness

Returns

Avalonia.Size

ArrangeChild Method

public Avalonia.Size ArrangeChild(Avalonia.Layout.Layoutable child, Avalonia.Size availableSize, Avalonia.Thickness padding, Avalonia.Thickness borderThickness)

Parameters

child Avalonia.Layout.Layoutable

availableSize Avalonia.Size

padding Avalonia.Thickness

borderThickness Avalonia.Thickness

Returns

Avalonia.Size

GetLayoutScale Method

Obtains layout scale of the given control.

public double GetLayoutScale(Avalonia.Layout.Layoutable control)

Parameters

control Avalonia.Layout.Layoutable

The control.

Returns

double

Exceptions

• Thrown when control has no root or returned layout scaling is invalid.

InvalidateSelfAndChildrenMeasure Method

Invalidates measure for given control and all visual children recursively.

public void InvalidateSelfAndChildrenMeasure(Avalonia.Layout.Layoutable control)

Parameters

control Avalonia.Layout.Layoutable

MeasureChild overloads

MeasureChild Method

public Avalonia.Size MeasureChild(Avalonia.Layout.Layoutable control, Avalonia.Size availableSize, Avalonia.Thickness padding)

Parameters

control Avalonia.Layout.Layoutable

availableSize Avalonia.Size

padding Avalonia.Thickness

Returns

Avalonia.Size

MeasureChild Method

public Avalonia.Size MeasureChild(Avalonia.Layout.Layoutable control, Avalonia.Size availableSize, Avalonia.Thickness padding, Avalonia.Thickness borderThickness)

Parameters

control Avalonia.Layout.Layoutable

availableSize Avalonia.Size

padding Avalonia.Thickness

borderThickness Avalonia.Thickness

Returns

Avalonia.Size

RoundLayoutPoint Method

public Avalonia.Point RoundLayoutPoint(Avalonia.Point point, double dpiScale)

Parameters

point Avalonia.Point

dpiScale double

Returns

Avalonia.Point

RoundLayoutSizeUp Method

Rounds a size to integer values for layout purposes, compensating for high DPI screen coordinates by rounding the size up to the nearest pixel.

public Avalonia.Size RoundLayoutSizeUp(Avalonia.Size size, double dpiScale)

Parameters

size Avalonia.Size

Input size.

dpiScale double

The DPI scale.

Returns

Avalonia.Size

Value of size that will be rounded under screen DPI.

Remarks

This is a layout helper method. It takes DPI into account and also does not return the rounded value if it is unacceptable for layout, e.g. Infinity or NaN. It's a helper associated with the UseLayoutRounding property and should not be used as a general rounding utility.

RoundLayoutThickness Method

Rounds a thickness to integer values for layout purposes, compensating for high DPI screen coordinates.

public Avalonia.Thickness RoundLayoutThickness(Avalonia.Thickness thickness, double dpiScale)

Parameters

thickness Avalonia.Thickness

Input thickness.

dpiScale double

The DPI scale.

Returns

Avalonia.Thickness

Value of thickness that will be rounded under screen DPI.

Remarks

This is a layout helper method. It takes DPI into account and also does not return the rounded value if it is unacceptable for layout, e.g. Infinity or NaN. It's a helper associated with the UseLayoutRounding property and should not be used as a general rounding utility.

RoundLayoutValue Method

Calculates the value to be used for layout rounding at high DPI by rounding the value up or down to the nearest pixel.

public double RoundLayoutValue(double value, double dpiScale)

Parameters

value double

Input value to be rounded.

dpiScale double

Ratio of screen's DPI to layout DPI

Returns

double

Adjusted value that will produce layout rounding on screen at high dpi.

Remarks

This is a layout helper method. It takes DPI into account and also does not return the rounded value if it is unacceptable for layout, e.g. Infinity or NaN. It's a helper associated with the UseLayoutRounding property and should not be used as a general rounding utility.

RoundLayoutValueUp Method

Calculates the value to be used for layout rounding at high DPI by rounding the value up to the nearest pixel.

public double RoundLayoutValueUp(double value, double dpiScale)

Parameters

value double

Input value to be rounded.

dpiScale double

Ratio of screen's DPI to layout DPI

Returns

double

Adjusted value that will produce layout rounding on screen at high dpi.

Remarks

This is a layout helper method. It takes DPI into account and also does not return the rounded value if it is unacceptable for layout, e.g. Infinity or NaN. It's a helper associated with the UseLayoutRounding property and should not be used as a general rounding utility.

Properties

Name	Description
LayoutEpsilon	Epsilon value used for certain layout calculations. Based on the value in WPF LayoutDoubleUtil.

LayoutEpsilon Property

Epsilon value used for certain layout calculations. Based on the value in WPF LayoutDoubleUtil.

public double LayoutEpsilon { get; set; }