com.itextpdf.layout

Class ElementPropertyContainerIPropertyContainer>

java.lang.Object

com.itextpdf.layout.ElementPropertyContainer

Type Parameters:

T - this type

All Implemented Interfaces:

IPropertyContainer

Direct Known Subclasses:

AbstractElement, RootElement, Style

public abstract class ElementPropertyContainerIPropertyContainer>
extends Object
implements IPropertyContainer

A generic abstract element that fits in a PDF layout object hierarchy. A superclass of all layout object implementations.

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<Integer,Object>	properties

Constructor Summary

Constructors

Constructor and Description
ElementPropertyContainer()

Method Summary

Modifier and Type	Method and Description
void	deleteOwnProperty(int property) Deletes the own property of this entity.
T1	getDefaultProperty(int property) Gets the default property from this entity.
T1	getOwnProperty(int property) Gets own property from this entity.
T1	getProperty(int property) Gets the property from this entity.
ISplitCharacters	getSplitCharacters() Gets a rule for splitting strings when they don't fit into one line.
Color	getStrokeColor() Gets the stroke color for the current element.
Float	getStrokeWidth() Gets the stroke width for the current element.
Integer	getTextRenderingMode() Gets the text rendering mode, a variable that determines whether showing text causes glyph outlines to be stroked, filled, used as a clipping boundary, or some combination of the three.
boolean	hasOwnProperty(int property) Checks if this entity has the specified property, i.e.
boolean	hasProperty(int property) Checks if this entity has the specified property.
T	setBackgroundColor(Color backgroundColor) Specifies a background color for the Element.
T	setBackgroundColor(Color backgroundColor, float opacity) Specifies a background color for the Element.
T	setBackgroundColor(Color backgroundColor, float extraLeft, float extraTop, float extraRight, float extraBottom) Specifies a background color for the Element, and extra space that must be counted as part of the background and therefore colored.
T	setBackgroundColor(Color backgroundColor, float opacity, float extraLeft, float extraTop, float extraRight, float extraBottom) Specifies a background color for the Element, and extra space that must be counted as part of the background and therefore colored.
T	setBaseDirection(BaseDirection baseDirection) This attribute specifies the base direction of directionally neutral text (i.e., text that doesn't have inherent directionality as defined in Unicode) in an element's content and attribute values.
T	setBold() Switch on the simulation of bold style for a font.
T	setBorder(Border border) Sets a border for all four edges of this Element with customizable color, width, pattern type.
T	setBorderBottom(Border border) Sets a border for the bottom limit of this Element with customizable color, width, pattern type.
T	setBorderBottomLeftRadius(BorderRadius borderRadius) Sets a border radius for the bottom left corner of this Element.
T	setBorderBottomRightRadius(BorderRadius borderRadius) Sets a border radius for the bottom right corner of this Element.
T	setBorderLeft(Border border) Sets a border for the left limit of this Element with customizable color, width, pattern type.
T	setBorderRadius(BorderRadius borderRadius) Sets a border radius for all four edges of this Element.
T	setBorderRight(Border border) Sets a border for the right limit of this Element with customizable color, width, pattern type.
T	setBorderTop(Border border) Sets a border for the upper limit of this Element with customizable color, width, pattern type.
T	setBorderTopLeftRadius(BorderRadius borderRadius) Sets a border radius for the top left corner of this Element.
T	setBorderTopRightRadius(BorderRadius borderRadius) Sets a border radius for the top right corner of this Element.
T	setCharacterSpacing(float charSpacing) Defines a custom spacing distance between all characters of a textual element.
T	setDestination(String destination) Sets a destination name that will be created when this element is drawn to content.
T	setFixedPosition(float left, float bottom, float width) Sets values for a absolute repositioning of the Element.
T	setFixedPosition(float left, float bottom, UnitValue width) Sets values for a absolute repositioning of the Element.
T	setFixedPosition(int pageNumber, float left, float bottom, float width) Sets values for a absolute repositioning of the Element.
T	setFixedPosition(int pageNumber, float left, float bottom, UnitValue width) Sets values for a absolute repositioning of the Element.
T	setFont(PdfFont font) Sets the font of this Element.
T	setFont(String font) Deprecated. This method will be removed in 7.2. Use setFontFamily(String...) instead.
T	setFontColor(Color fontColor) Sets the font color of this Element.
T	setFontColor(Color fontColor, float opacity) Sets the font color of this Element and the opacity of the text.
T	setFontFamily(List<String> fontFamilyNames) Sets the preferable font families for this Element.
T	setFontFamily(String... fontFamilyNames) Sets the preferable font families for this Element.
T	setFontKerning(FontKerning fontKerning) Enable or disable kerning.
T	setFontScript(Character.UnicodeScript script) Sets the writing system for this text element.
T	setFontSize(float fontSize) Sets the font size of this Element, measured in points.
T	setHorizontalAlignment(HorizontalAlignment horizontalAlignment) Sets the horizontal alignment of this Element.
T	setHyphenation(HyphenationConfig hyphenationConfig) Sets a custom hyphenation configuration which will hyphenate words automatically accordingly to the language and country.
T	setItalic() Switch on the simulation of italic style for a font.
T	setLineThrough() Sets default line-through attributes for text.
T	setOpacity(Float opacity) Sets an opacity of the given element.
void	setProperty(int property, Object value) Sets a property for this entity.
T	setRelativePosition(float left, float top, float right, float bottom) Sets values for a relative repositioning of the Element.
T	setSplitCharacters(ISplitCharacters splitCharacters) Sets a rule for splitting strings when they don't fit into one line.
T	setStrokeColor(Color strokeColor) Sets the stroke color for the current element.
T	setStrokeWidth(float strokeWidth) Sets the stroke width for the current element.
T	setTextAlignment(TextAlignment alignment) Sets the text alignment of this Element.
T	setTextRenderingMode(int textRenderingMode) Sets the text rendering mode, a variable that determines whether showing text causes glyph outlines to be stroked, filled, used as a clipping boundary, or some combination of the three.
T	setUnderline() Sets default underline attributes for text.
T	setUnderline(Color color, float opacity, float thickness, float thicknessMul, float yPosition, float yPositionMul, int lineCapStyle) Sets an horizontal line that can be an underline or a strikethrough.
T	setUnderline(Color color, float thickness, float thicknessMul, float yPosition, float yPositionMul, int lineCapStyle) Sets an horizontal line that can be an underline or a strikethrough.
T	setUnderline(float thickness, float yPosition) Sets an horizontal line that can be an underline or a strikethrough.
T	setWordSpacing(float wordSpacing) Defines a custom spacing distance between words of a textual element.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

properties

protected Map<Integer,Object> properties

Constructor Detail

ElementPropertyContainer

public ElementPropertyContainer()

Method Detail

setProperty

public void setProperty(int property,
                        Object value)

Description copied from interface: IPropertyContainer

Sets a property for this entity.

Specified by:

setProperty in interface IPropertyContainer

Parameters:

property - the property to be set

value - the value of the property

hasProperty

public boolean hasProperty(int property)

Description copied from interface: IPropertyContainer

Checks if this entity has the specified property. Compared to IPropertyContainer.hasOwnProperty(int), this method can check parent's properties, styles, etc, depending on the origin of the instance

Specified by:

hasProperty in interface IPropertyContainer

Parameters:

property - the property to be checked

Returns:

true if this instance has given property, false otherwise

hasOwnProperty

public boolean hasOwnProperty(int property)

Description copied from interface: IPropertyContainer

Checks if this entity has the specified property, i.e. if it was set to this very element earlier

Specified by:

hasOwnProperty in interface IPropertyContainer

Parameters:

property - the property to be checked

Returns:

true if this instance has given own property, false otherwise

deleteOwnProperty

public void deleteOwnProperty(int property)

Description copied from interface: IPropertyContainer

Deletes the own property of this entity.

Specified by:

deleteOwnProperty in interface IPropertyContainer

Parameters:

property - the property to be deleted

getProperty

public  T1 getProperty(int property)

Description copied from interface: IPropertyContainer

Gets the property from this entity. Compared to IPropertyContainer.getOwnProperty(int), this method can check parent's properties, styles, etc, depending on the origin of the instance

Specified by:

getProperty in interface IPropertyContainer

Type Parameters:

T1 - the return type associated with the property

Parameters:

property - the property to be retrieved

Returns:

the value of the given property. null will be returned if the property value was not found

getOwnProperty

public  T1 getOwnProperty(int property)

Description copied from interface: IPropertyContainer

Gets own property from this entity. The property must have been set earlier to this entity. If the property is not found, null will be returned.

Specified by:

getOwnProperty in interface IPropertyContainer

Type Parameters:

T1 - the return type associated with the property

Parameters:

property - the property to be retrieved

Returns:

the value of the given own property. null will be returned if the property value was not found

getDefaultProperty

public  T1 getDefaultProperty(int property)

Description copied from interface: IPropertyContainer

Gets the default property from this entity.

Specified by:

getDefaultProperty in interface IPropertyContainer

Type Parameters:

T1 - the return type associated with the property

Parameters:

property - the property to be retrieved

Returns:

the default property value. If the default property is not defined, null will be returned

setRelativePosition

public T setRelativePosition(float left,
                             float top,
                             float right,
                             float bottom)

Sets values for a relative repositioning of the Element. Also has as a side effect that the Element's Property.POSITION is changed to relative. The default implementation in AbstractRenderer treats left and top as the most important values. Only if left == 0 will right be used for the calculation; ditto for top vs. bottom.

Parameters:

left - movement to the left

top - movement upwards on the page

right - movement to the right

bottom - movement downwards on the page

Returns:

this Element.

See Also:

LayoutPosition.RELATIVE

setFixedPosition

public T setFixedPosition(float left,
                          float bottom,
                          float width)

Sets values for a absolute repositioning of the Element. The coordinates specified correspond to the bottom-left corner of the element and it grows upwards. Also has as a side effect that the Element's Property.POSITION is changed to fixed.

Parameters:

left - horizontal position of the bottom-left corner on the page

bottom - vertical position of the bottom-left corner on the page

width - a floating point value measured in points.

Returns:

this Element.

setFixedPosition

public T setFixedPosition(float left,
                          float bottom,
                          UnitValue width)

Sets values for a absolute repositioning of the Element. The coordinates specified correspond to the bottom-left corner of the element and it grows upwards. Also has as a side effect that the Element's Property.POSITION is changed to fixed.

Parameters:

left - horizontal position of the bottom-left corner on the page

bottom - vertical position of the bottom-left corner on the page

width - a UnitValue

Returns:

this Element.

setFixedPosition

public T setFixedPosition(int pageNumber,
                          float left,
                          float bottom,
                          float width)

Sets values for a absolute repositioning of the Element. The coordinates specified correspond to the bottom-left corner of the element and it grows upwards. Also has as a side effect that the Element's Property.POSITION is changed to fixed.

Parameters:

pageNumber - the page where the element must be positioned

left - horizontal position of the bottom-left corner on the page

bottom - vertical position of the bottom-left corner on the page

width - a floating point value measured in points.

Returns:

this Element.

setFixedPosition

public T setFixedPosition(int pageNumber,
                          float left,
                          float bottom,
                          UnitValue width)

Sets values for a absolute repositioning of the Element. The coordinates specified correspond to the bottom-left corner of the element and it grows upwards. Also has as a side effect that the Element's Property.POSITION is changed to fixed.

Parameters:

pageNumber - the page where the element must be positioned

left - horizontal position of the bottom-left corner on the page

bottom - vertical position of the bottom-left corner on the page

width - a floating point value measured in points.

Returns:

this Element.

setHorizontalAlignment

public T setHorizontalAlignment(HorizontalAlignment horizontalAlignment)

Sets the horizontal alignment of this Element.

Parameters:

horizontalAlignment - an enum value of type HorizontalAlignment

Returns:

this Element.

setFont

public T setFont(PdfFont font)

Sets the font of this Element.

This property overrides the value set by setFontFamily(java.lang.String...). Font is set either via exact PdfFont instance or via font-family name that should correspond to the font in FontProvider, but not both.

Parameters:

font - a font

Returns:

this Element.

setFontFamily

public T setFontFamily(String... fontFamilyNames)

Sets the preferable font families for this Element. Note that FontProvider shall be set as well. See RootElement.setFontProvider(FontProvider)

This property overrides the value set by setFont(PdfFont). Font is set either via exact PdfFont instance or via font-family name that should correspond to the font in FontProvider, but not both.

All String that are passed as argument are directly handled as a collection of font family names, without any pre-processing. Every font family name is treated as a preferable font-family to be used inside the element. The fontFamilyNames argument is interpreted as as an ordered list, where every next font-family should be used if font for the previous one was not found or doesn't contain required glyphs.

Parameters:

fontFamilyNames - defines an ordered list of preferable font families for this Element.

Returns:

this Element.

See Also:

StandardFontFamilies

setFontFamily

public T setFontFamily(List<String> fontFamilyNames)

Sets the preferable font families for this Element. Note that FontProvider shall be set as well. See RootElement.setFontProvider(FontProvider)

This property overrides the value set by setFont(PdfFont). Font is set either via exact PdfFont instance or via font-family name that should correspond to the font in FontProvider, but not both.

All String that are passed as argument are directly handled as a collection of font family names, without any pre-processing. Every font family name is treated as a preferable font-family to be used inside the element. The fontFamilyNames argument is interpreted as as an ordered list, where every next font-family should be used if font for the previous one was not found or doesn't contain required glyphs.

Parameters:

fontFamilyNames - defines an ordered list of preferable font families for this Element.

Returns:

this Element.

See Also:

StandardFontFamilies

setFont

@Deprecated
public T setFont(String font)

Deprecated. This method will be removed in 7.2. Use setFontFamily(String...) instead.

Sets the font family of this Element. Note that FontProvider shall be set as well. See RootElement.setFontProvider(FontProvider)

Parameters:

font - a font name to fetch from FontProvider

Returns:

this Element.

See Also:

StandardFontFamilies

setFontColor

public T setFontColor(Color fontColor)

Sets the font color of this Element.

Parameters:

fontColor - a Color for the text in this Element.

Returns:

this Element.

setFontColor

public T setFontColor(Color fontColor,
                      float opacity)

Sets the font color of this Element and the opacity of the text.

Parameters:

fontColor - a Color for the text in this Element.

opacity - an opacity for the text in this Element; a float between 0 and 1, where 1 stands for fully opaque color and 0 - for fully transparent.

Returns:

this Element.

setFontSize

public T setFontSize(float fontSize)

Sets the font size of this Element, measured in points.

Parameters:

fontSize - a floating point value

Returns:

this Element.

setTextAlignment

public T setTextAlignment(TextAlignment alignment)

Sets the text alignment of this Element.

Parameters:

alignment - an enum value of type TextAlignment

Returns:

this Element.

setCharacterSpacing

public T setCharacterSpacing(float charSpacing)

Defines a custom spacing distance between all characters of a textual element. The character-spacing parameter is added to the glyph's horizontal or vertical displacement (depending on the writing mode).

Parameters:

charSpacing - a floating point value

Returns:

this Element.

setWordSpacing

public T setWordSpacing(float wordSpacing)

Defines a custom spacing distance between words of a textual element. This value works exactly like the character spacing, but only kicks in at word boundaries.

Parameters:

wordSpacing - a floating point value

Returns:

this Element.

setFontKerning

public T setFontKerning(FontKerning fontKerning)

Enable or disable kerning. Some fonts may specify kern pairs, i.e. pair of glyphs, between which the amount of horizontal space is adjusted. This adjustment is typically negative, e.g. in "AV" pair the glyphs will typically be moved closer to each other.

Parameters:

fontKerning - an enum value as a boolean wrapper specifying whether or not to apply kerning

Returns:

this Element.

setBackgroundColor

public T setBackgroundColor(Color backgroundColor)

Specifies a background color for the Element.

Parameters:

backgroundColor - the background color

Returns:

this Element.

setBackgroundColor

public T setBackgroundColor(Color backgroundColor,
                            float opacity)

Specifies a background color for the Element.

Parameters:

backgroundColor - the background color

opacity - the background color opacity; a float between 0 and 1, where 1 stands for fully opaque color and 0 - for fully transparent.

Returns:

this Element.

setBackgroundColor

public T setBackgroundColor(Color backgroundColor,
                            float extraLeft,
                            float extraTop,
                            float extraRight,
                            float extraBottom)

Specifies a background color for the Element, and extra space that must be counted as part of the background and therefore colored.

Parameters:

backgroundColor - the background color

extraLeft - extra coloring to the left side

extraTop - extra coloring at the top

extraRight - extra coloring to the right side

extraBottom - extra coloring at the bottom

Returns:

this Element.

setBackgroundColor

public T setBackgroundColor(Color backgroundColor,
                            float opacity,
                            float extraLeft,
                            float extraTop,
                            float extraRight,
                            float extraBottom)

Specifies a background color for the Element, and extra space that must be counted as part of the background and therefore colored.

Parameters:

backgroundColor - the background color

opacity - the background color opacity; a float between 0 and 1, where 1 stands for fully opaque color and 0 - for fully transparent

extraLeft - extra coloring to the left side

extraTop - extra coloring at the top

extraRight - extra coloring to the right side

extraBottom - extra coloring at the bottom

Returns:

this Element.

setBorder

public T setBorder(Border border)

Sets a border for all four edges of this Element with customizable color, width, pattern type.

Parameters:

border - a customized Border

Returns:

this Element.

setBorderTop

public T setBorderTop(Border border)

Sets a border for the upper limit of this Element with customizable color, width, pattern type.

Parameters:

border - a customized Border

Returns:

this Element.

setBorderRight

public T setBorderRight(Border border)

Sets a border for the right limit of this Element with customizable color, width, pattern type.

Parameters:

border - a customized Border

Returns:

this Element.

setBorderBottom

public T setBorderBottom(Border border)

Sets a border for the bottom limit of this Element with customizable color, width, pattern type.

Parameters:

border - a customized Border

Returns:

this Element.

setBorderLeft

public T setBorderLeft(Border border)

Sets a border for the left limit of this Element with customizable color, width, pattern type.

Parameters:

border - a customized Border

Returns:

this Element.

setBorderRadius

public T setBorderRadius(BorderRadius borderRadius)

Sets a border radius for all four edges of this Element.

Parameters:

borderRadius - a customized BorderRadius

Returns:

this Element.

setBorderBottomLeftRadius

public T setBorderBottomLeftRadius(BorderRadius borderRadius)

Sets a border radius for the bottom left corner of this Element.

Parameters:

borderRadius - a customized BorderRadius

Returns:

this Element.

setBorderBottomRightRadius

public T setBorderBottomRightRadius(BorderRadius borderRadius)

Sets a border radius for the bottom right corner of this Element.

Parameters:

borderRadius - a customized BorderRadius

Returns:

this Element.

setBorderTopLeftRadius

public T setBorderTopLeftRadius(BorderRadius borderRadius)

Sets a border radius for the top left corner of this Element.

Parameters:

borderRadius - a customized BorderRadius

Returns:

this Element.

setBorderTopRightRadius

public T setBorderTopRightRadius(BorderRadius borderRadius)

Sets a border radius for the top right corner of this Element.

Parameters:

borderRadius - a customized BorderRadius

Returns:

this Element.

setSplitCharacters

public T setSplitCharacters(ISplitCharacters splitCharacters)

Sets a rule for splitting strings when they don't fit into one line. The default implementation is DefaultSplitCharacters

Parameters:

splitCharacters - an implementation of ISplitCharacters

Returns:

this Element.

getSplitCharacters

public ISplitCharacters getSplitCharacters()

Gets a rule for splitting strings when they don't fit into one line.

Returns:

the current string splitting rule, an implementation of ISplitCharacters

getTextRenderingMode

public Integer getTextRenderingMode()

Gets the text rendering mode, a variable that determines whether showing text causes glyph outlines to be stroked, filled, used as a clipping boundary, or some combination of the three.

Returns:

the current text rendering mode

See Also:

PdfCanvasConstants.TextRenderingMode

setTextRenderingMode

public T setTextRenderingMode(int textRenderingMode)

Sets the text rendering mode, a variable that determines whether showing text causes glyph outlines to be stroked, filled, used as a clipping boundary, or some combination of the three.

Parameters:

textRenderingMode - an int value

Returns:

this Element.

See Also:

PdfCanvasConstants.TextRenderingMode

getStrokeColor

public Color getStrokeColor()

Gets the stroke color for the current element. The stroke color is the color of the outlines or edges of a shape.

Returns:

the current stroke color

setStrokeColor

public T setStrokeColor(Color strokeColor)

Sets the stroke color for the current element. The stroke color is the color of the outlines or edges of a shape.

Parameters:

strokeColor - a new stroke color

Returns:

this Element.

getStrokeWidth

public Float getStrokeWidth()

Gets the stroke width for the current element. The stroke width is the width of the outlines or edges of a shape.

Returns:

the current stroke width

setStrokeWidth

public T setStrokeWidth(float strokeWidth)

Sets the stroke width for the current element. The stroke width is the width of the outlines or edges of a shape.

Parameters:

strokeWidth - a new stroke width

Returns:

this Element.

setBold

public T setBold()

Switch on the simulation of bold style for a font. Be aware that using correct bold font is highly preferred over this option.

Returns:

this element

setItalic

public T setItalic()

Switch on the simulation of italic style for a font. Be aware that using correct italic (oblique) font is highly preferred over this option.

Returns:

this element

setLineThrough

public T setLineThrough()

Sets default line-through attributes for text. See setUnderline(Color, float, float, float, float, int) for more fine tuning.

Returns:

this element

setUnderline

public T setUnderline()

Sets default underline attributes for text. See other overloads for more fine tuning.

Returns:

this element

setUnderline

public T setUnderline(float thickness,
                      float yPosition)

Sets an horizontal line that can be an underline or a strikethrough. Actually, the line can be anywhere vertically and has always the text width. Multiple call to this method will produce multiple lines.

Parameters:

thickness - the absolute thickness of the line

yPosition - the absolute y position relative to the baseline

Returns:

this element

setUnderline

public T setUnderline(Color color,
                      float thickness,
                      float thicknessMul,
                      float yPosition,
                      float yPositionMul,
                      int lineCapStyle)

Sets an horizontal line that can be an underline or a strikethrough. Actually, the line can be anywhere vertically due to position parameter. Multiple call to this method will produce multiple lines.

The thickness of the line will be thickness + thicknessMul * fontSize. The position of the line will be baseLine + yPosition + yPositionMul * fontSize.

Parameters:

color - the color of the line or null to follow the text color

thickness - the absolute thickness of the line

thicknessMul - the thickness multiplication factor with the font size

yPosition - the absolute y position relative to the baseline

yPositionMul - the position multiplication factor with the font size

lineCapStyle - the end line cap style. Allowed values are enumerated in PdfCanvasConstants.LineCapStyle

Returns:

this element

setUnderline

public T setUnderline(Color color,
                      float opacity,
                      float thickness,
                      float thicknessMul,
                      float yPosition,
                      float yPositionMul,
                      int lineCapStyle)

Sets an horizontal line that can be an underline or a strikethrough. Actually, the line can be anywhere vertically due to position parameter. Multiple call to this method will produce multiple lines.

The thickness of the line will be thickness + thicknessMul * fontSize. The position of the line will be baseLine + yPosition + yPositionMul * fontSize.

Parameters:

color - the color of the line or null to follow the text color

opacity - the opacity of the line; a float between 0 and 1, where 1 stands for fully opaque color and 0 - for fully transparent

thickness - the absolute thickness of the line

thicknessMul - the thickness multiplication factor with the font size

yPosition - the absolute y position relative to the baseline

yPositionMul - the position multiplication factor with the font size

lineCapStyle - the end line cap style. Allowed values are enumerated in PdfCanvasConstants.LineCapStyle

Returns:

this element

setBaseDirection

public T setBaseDirection(BaseDirection baseDirection)

This attribute specifies the base direction of directionally neutral text (i.e., text that doesn't have inherent directionality as defined in Unicode) in an element's content and attribute values.

Parameters:

baseDirection - base direction

Returns:

this element

setHyphenation

public T setHyphenation(HyphenationConfig hyphenationConfig)

Sets a custom hyphenation configuration which will hyphenate words automatically accordingly to the language and country.

Parameters:

hyphenationConfig - The hyphenation configuration

Returns:

this element

setFontScript

public T setFontScript(Character.UnicodeScript script)

Sets the writing system for this text element.

Parameters:

script - a new script type

Returns:

this Element.

setDestination

public T setDestination(String destination)

Sets a destination name that will be created when this element is drawn to content.

Parameters:

destination - the destination name to be created

Returns:

this Element.

setOpacity

public T setOpacity(Float opacity)

Sets an opacity of the given element. It will affect element content, borders and background. Note, that it will also affect all element children, as they are the content of the given element.

Parameters:

opacity - a float between 0 and 1, where 1 stands for fully opaque element and 0 - for fully transparent

Returns:

this Element.