Package 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 Details

    • 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 Details

    • 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 Details

    • 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