com.itextpdf.kernel.pdf.layer

Class PdfLayer

java.lang.Object

com.itextpdf.kernel.pdf.PdfObjectWrapper<PdfDictionary>

com.itextpdf.kernel.pdf.layer.PdfLayer

All Implemented Interfaces:

IPdfOCG

public class PdfLayer
extends PdfObjectWrapper<PdfDictionary>
implements IPdfOCG

An optional content group is a dictionary representing a collection of graphics that can be made visible or invisible dynamically by users of viewer applications. In iText they are referenced as layers.

To be able to be wrapped with this PdfObjectWrapper the PdfObject must be indirect.

Field Summary

Fields

Modifier and Type	Field and Description
protected List<PdfLayer>	children
protected boolean	locked
protected boolean	on
protected boolean	onPanel
protected PdfLayer	parent
protected String	title Used for titling group of objects but not actually grouping them.

Constructor Summary

Constructors

Constructor and Description
PdfLayer(PdfDictionary layerDictionary) Creates a new layer by existing dictionary, which must be an indirect object.
PdfLayer(String name, PdfDocument document) Creates a new layer by its name and document.

Method Summary

Modifier and Type	Method and Description
void	addChild(PdfLayer childLayer) Adds a child layer.
static void	addOCGRadioGroup(PdfDocument document, List<PdfLayer> group) Use this method to set a collection of optional content groups whose states are intended to follow a "radio button" paradigm.
static PdfLayer	createTitle(String title, PdfDocument document) Creates a title layer.
protected static PdfLayer	createTitleSilent(String title, PdfDocument document) Creates a title layer without registering it in PdfOCProperties.
List<PdfLayer>	getChildren() Gets the list of the current child layers of the layer.
protected PdfDocument	getDocument() Gets the PdfDocument that owns that layer.
PdfIndirectReference	getIndirectReference() Gets the indirect reference to the current layer object.
Collection<PdfName>	getIntents() Gets a collection of current intents specified for this layer.
PdfLayer	getParent() Gets the parent of this layer, be it a title layer, or a usual one.
String	getTitle() Gets the title of the layer if it is a title layer, or null if it is a usual layer.
protected PdfDictionary	getUsage() Gets the /Usage dictionary, creating a new one if necessary.
boolean	isLocked() Gets whether the layer is currently locked or not.
boolean	isOn() Gets the initial visibility of the layer when the document is opened.
boolean	isOnPanel() Gets the layer visibility in Acrobat's layer panel
protected boolean	isWrappedObjectMustBeIndirect() Defines if the object behind this wrapper must be an indirect object in the resultant document.
void	setCreatorInfo(String creator, String subtype) Used by the creating application to store application-specific data associated with this optional content group.
void	setExport(boolean export) Specifies the recommended state for content in this group when the document (or part of it) is saved by a viewer application to a format that does not support optional content (for example, an earlier version of PDF or a raster image format).
void	setIntents(List<PdfName> intents) Sets the intents of the layer.
void	setLanguage(String lang, boolean preferred) Specifies the language of the content controlled by this optional content group
void	setLocked(boolean locked) Use this method to lock an optional content group.
void	setName(String name) Sets the name of the layer to be displayed in the Layers panel.
void	setOn(boolean on) Sets the initial visibility of the layer when the document is opened.
void	setOnPanel(boolean onPanel) Sets the visibility of the layer in Acrobat's layer panel.
void	setPageElement(String pe) Indicates that the group contains a pagination artifact.
void	setPrint(String subtype, boolean printState) Specifies that the content in this group is intended for use in printing
void	setUser(String type, String... names) Specifies one or more users for whom this optional content group is primarily intended.
void	setView(boolean view) Indicates that the group should be set to that state when the document is opened in a viewer application.
void	setZoom(float min, float max) Specifies a range of magnifications at which the content in this optional content group is best viewed.

Methods inherited from class com.itextpdf.kernel.pdf.PdfObjectWrapper

ensureObjectIsAddedToDocument, ensureUnderlyingObjectHasIndirectReference, flush, getPdfObject, isFlushed, makeIndirect, makeIndirect, markObjectAsIndirect, setForbidRelease, setModified, setPdfObject, unsetForbidRelease

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.itextpdf.kernel.pdf.layer.IPdfOCG

getPdfObject

Field Detail

title

protected String title

Used for titling group of objects but not actually grouping them.

on

protected boolean on

onPanel

protected boolean onPanel

locked

protected boolean locked

parent

protected PdfLayer parent

children

protected List<PdfLayer> children

Constructor Detail

PdfLayer

public PdfLayer(PdfDictionary layerDictionary)

Creates a new layer by existing dictionary, which must be an indirect object.

Parameters:

layerDictionary - the layer dictionary, must have an indirect reference.

PdfLayer

public PdfLayer(String name,
                PdfDocument document)

Creates a new layer by its name and document.

Parameters:

name - the layer name

document - the PdfDocument which the layer belongs to

Method Detail

createTitle

public static PdfLayer createTitle(String title,
                                   PdfDocument document)

Creates a title layer. A title layer is not really a layer but a collection of layers under the same title heading.

Parameters:

title - the title text

document - the PdfDocument

Returns:

the title layer

addOCGRadioGroup

public static void addOCGRadioGroup(PdfDocument document,
                                    List<PdfLayer> group)

Use this method to set a collection of optional content groups whose states are intended to follow a "radio button" paradigm. That is, the state of at most one optional content group in the array should be ON at a time: if one group is turned ON, all others must be turned OFF.

Parameters:

document - the PdfDocument

group - the radio group

addChild

public void addChild(PdfLayer childLayer)

Adds a child layer. Nested layers can only have one parent.

Parameters:

childLayer - the child layer

getParent

public PdfLayer getParent()

Gets the parent of this layer, be it a title layer, or a usual one.

Returns:

the parent of the layer, or null if it has no parent

setName

public void setName(String name)

Sets the name of the layer to be displayed in the Layers panel.

Parameters:

name - the name of the layer.

isOn

public boolean isOn()

Gets the initial visibility of the layer when the document is opened.

Returns:

the initial visibility of the layer

setOn

public void setOn(boolean on)

Sets the initial visibility of the layer when the document is opened.

Parameters:

on - the initial visibility of the layer

isLocked

public boolean isLocked()

Gets whether the layer is currently locked or not. If the layer is locked, it will not be possible to change its state (on/off) in a viewer.

Returns:

true if the layer is currently locked, false otherwise.

setLocked

public void setLocked(boolean locked)

Use this method to lock an optional content group. The state of a locked group cannot be changed through the user interface of a viewer application. Producers can use this entry to prevent the visibility of content that depends on these groups from being changed by users.

Parameters:

locked - sets whether the layer is currently locked or not

isOnPanel

public boolean isOnPanel()

Gets the layer visibility in Acrobat's layer panel

Returns:

the layer visibility in Acrobat's layer panel

setOnPanel

public void setOnPanel(boolean onPanel)

Sets the visibility of the layer in Acrobat's layer panel. If false the layer cannot be directly manipulated by the user. Note that any children layers will also be absent from the panel.

Parameters:

onPanel - the visibility of the layer in Acrobat's layer panel

getIntents

public Collection<PdfName> getIntents()

Gets a collection of current intents specified for this layer. The default value is PdfName.View, so it will be the only element of the resultant collection if no intents are currently specified.

Returns:

the collection of intents.

setIntents

public void setIntents(List<PdfName> intents)

Sets the intents of the layer.

Parameters:

intents - the list of intents.

setCreatorInfo

public void setCreatorInfo(String creator,
                           String subtype)

Used by the creating application to store application-specific data associated with this optional content group.

Parameters:

creator - a text string specifying the application that created the group

subtype - a string defining the type of content controlled by the group. Suggested values include but are not limited to Artwork, for graphic-design or publishing applications, and Technical, for technical designs such as building plans or schematics

setLanguage

public void setLanguage(String lang,
                        boolean preferred)

Specifies the language of the content controlled by this optional content group

Parameters:

lang - a language string which specifies a language and possibly a locale (for example, es-MX represents Mexican Spanish)

preferred - used by viewer applications when there is a partial match but no exact match between the system language and the language strings in all usage dictionaries

setExport

public void setExport(boolean export)

Specifies the recommended state for content in this group when the document (or part of it) is saved by a viewer application to a format that does not support optional content (for example, an earlier version of PDF or a raster image format).

Parameters:

export - the export state

setZoom

public void setZoom(float min,
                    float max)

Specifies a range of magnifications at which the content in this optional content group is best viewed.

Parameters:

min - the minimum recommended magnification factors at which the group should be ON. A negative value will set the default to 0

max - the maximum recommended magnification factor at which the group should be ON. A negative value will set the largest possible magnification supported by the viewer application

setPrint

public void setPrint(String subtype,
                     boolean printState)

Specifies that the content in this group is intended for use in printing

Parameters:

subtype - a name specifying the kind of content controlled by the group; for example, Trapping, PrintersMarks and Watermark

printState - indicates that the group should be set to that state when the document is printed from a viewer application

setView

public void setView(boolean view)

Indicates that the group should be set to that state when the document is opened in a viewer application.

Parameters:

view - the view state

setUser

public void setUser(String type,
                    String... names)

Specifies one or more users for whom this optional content group is primarily intended.

Parameters:

type - a name that can be Ind (individual), Ttl (title), or Org (organization).

names - one or more text strings representing the name(s) of the individual, position or organization

setPageElement

public void setPageElement(String pe)

Indicates that the group contains a pagination artifact.

Parameters:

pe - one of the following names: "HF" (Header Footer), "FG" (Foreground), "BG" (Background), or "L" (Logo).

getIndirectReference

public PdfIndirectReference getIndirectReference()

Gets the indirect reference to the current layer object.

Specified by:

getIndirectReference in interface IPdfOCG

Returns:

the indirect reference to the object representing the layer

getTitle

public String getTitle()

Gets the title of the layer if it is a title layer, or null if it is a usual layer.

Returns:

the title of the layer if it is a title layer, or null if it is a usual layer

getChildren

public List<PdfLayer> getChildren()

Gets the list of the current child layers of the layer. BE CAREFUL! Do not try to add a child layer using the resultant child list, use #addChild method instead.

Returns:

the list of the current child layers, null if the layer has no children.

isWrappedObjectMustBeIndirect

protected boolean isWrappedObjectMustBeIndirect()

Description copied from class: PdfObjectWrapper

Defines if the object behind this wrapper must be an indirect object in the resultant document.

If this method returns true it doesn't necessarily mean that object must be in the indirect state at any moment, but rather defines that when the object will be written to the document it will be transformed into indirect object if it's not indirect yet.

Return value of this method shouldn't depend on any logic, it should return always true or false.

Specified by:

isWrappedObjectMustBeIndirect in class PdfObjectWrapper<PdfDictionary>

Returns:

true if in the resultant document the object behind the wrapper must be indirect, otherwise false.

getDocument

protected PdfDocument getDocument()

Gets the PdfDocument that owns that layer.

Returns:

the PdfDocument that owns that layer

createTitleSilent

protected static PdfLayer createTitleSilent(String title,
                                            PdfDocument document)

Creates a title layer without registering it in PdfOCProperties.

Parameters:

title - the title of the layer

document - the document this title layer belongs to

Returns:

the created layer

getUsage

protected PdfDictionary getUsage()

Gets the /Usage dictionary, creating a new one if necessary.

Returns:

the /Usage dictionary