pdftron::PDF::OCG::OCMD Class Reference

The OCMD object represents an Optional Content Membership Dictionary (OCMD) that allows the visibility of optional content to depend on the states in a set of optional-content groups (OCG::Group). More...

#include <OCMD.h>

List of all members.

Public Types

enum  VisibilityPolicyType { e_AllOn, e_AnyOn, e_AnyOff, e_AllOff }
 Visibility Policy Type. More...

Public Member Functions

 OCMD (SDF::Obj ocmd)
 Creates a new optional-content group membership dictionary (OCMD) object from an existing SDF/Cos object.
bool IsValid () const
SDF::Obj GetOCGs () const
 Returns the optional-content groups listed under 'OCGs' entry in the object dictionary.
VisibilityPolicyType GetVisibilityPolicy () const
 Returns the optional-content membership dictionary's visibility policy, which determines the visibility of content with respect to the ON-OFF state of OCGs listed in the dictionary.
void SetVisibilityPolicy (VisibilityPolicyType vis_policy)
 Sets the optional-content membership dictionary's visibility policy, which determines the visibility of content with respect to the ON-OFF state of OCGs listed in the dictionary.
SDF::Obj GetVisibilityExpression () const
bool IsCurrentlyVisible (const class Context &context) const
SDF::Obj GetSDFObj () const
 OCMD (const OCMD &g)
 Copy constructor.
OCMDoperator= (const OCMD &g)

Static Public Member Functions

static OCMD Create (PDFDoc &doc, SDF::Obj ocgs, VisibilityPolicyType vis_policy)
 Creates a new optional-content membership dictionary (OCMD) object in the given document for the given groups and visibility policy.


Detailed Description

The OCMD object represents an Optional Content Membership Dictionary (OCMD) that allows the visibility of optional content to depend on the states in a set of optional-content groups (OCG::Group).

The object directly corresponds to the OCMD dictionary (Section 4.10.1 'Optional Content Groups' in PDF Reference).

An OCMD collects a set of OCGs. It sets a visibility policy, so that content in the member groups is visible only when all groups are ON or OFF, or when any of the groups is ON or OFF. This makes it possible to set up complex dependencies among groups. For example, an object can be visible only if some other conditions are met (such as if another layer is visible).


Member Enumeration Documentation

Visibility Policy Type.

A Visibility Policy is used to determine whether an PDF::Element is visible in a given OCG::Context, depending on whether all groups in OCGs array are "ON" or "OFF", or when any of the groups is "ON" or "OFF".

Enumerator:
e_AllOn  visible only if all of the entries in OCGs are ON.
e_AnyOn  visible if any of the entries in OCGs are ON.
e_AnyOff  visible if any of the entries in OCGs are OFF.
e_AllOff  visible only if all of the entries in OCGs are OFF.


Constructor & Destructor Documentation

pdftron::PDF::OCG::OCMD::OCMD ( SDF::Obj  ocmd  ) 

Creates a new optional-content group membership dictionary (OCMD) object from an existing SDF/Cos object.

pdftron::PDF::OCG::OCMD::OCMD ( const OCMD g  ) 

Copy constructor.


Member Function Documentation

static OCMD pdftron::PDF::OCG::OCMD::Create ( PDFDoc doc,
SDF::Obj  ocgs,
VisibilityPolicyType  vis_policy 
) [static]

Creates a new optional-content membership dictionary (OCMD) object in the given document for the given groups and visibility policy.

Parameters:
doc The document in which the new OCMD will be created.
ocgs An array of optional-content groups (OCGs) to be members of the dictionary.
policy The visibility policy that determines the visibility of content with respect to the ON-OFF state of OCGs listed in the dictionary.
Returns:
The newly created OCG::OCMD object.

bool pdftron::PDF::OCG::OCMD::IsValid (  )  const

Returns:
True if this is a valid (non-null) OCMD, false otherwise.

SDF::Obj pdftron::PDF::OCG::OCMD::GetOCGs (  )  const

Returns the optional-content groups listed under 'OCGs' entry in the object dictionary.

Returns:
A dictionary (for a single OCG::Group object), an SDF::Obj array (for multiple OCG::Group objects) or NULL (for an empty OCMD).

VisibilityPolicyType pdftron::PDF::OCG::OCMD::GetVisibilityPolicy (  )  const

Returns the optional-content membership dictionary's visibility policy, which determines the visibility of content with respect to the ON-OFF state of OCGs listed in the dictionary.

Returns:
The visibility policy.

void pdftron::PDF::OCG::OCMD::SetVisibilityPolicy ( VisibilityPolicyType  vis_policy  ) 

Sets the optional-content membership dictionary's visibility policy, which determines the visibility of content with respect to the ON-OFF state of OCGs listed in the dictionary.

Parameters:
vis_policy New visibility policy.

SDF::Obj pdftron::PDF::OCG::OCMD::GetVisibilityExpression (  )  const

Returns:
If the PDOCMD has a visibility expression entry, return the SDF::Obj array object representing the expression, otherwise returns NULL.

bool pdftron::PDF::OCG::OCMD::IsCurrentlyVisible ( const class Context context  )  const

Returns:
true if content tagged with this OCMD is visible in the given context, false if it is hidden.
Based on the optional-content groups listed in the dictionary, the current ON-OFF state of those groups within the specified context, and the dictionary's visibility policy, test whether the content tagged with this dictionary would be visible.

Parameters:
context The context in which the visibility of content is tested.

SDF::Obj pdftron::PDF::OCG::OCMD::GetSDFObj (  )  const

Returns:
Pointer to the underlying SDF/Cos object.

OCMD& pdftron::PDF::OCG::OCMD::operator= ( const OCMD g  ) 


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