Foxit PDF SDK
FSDK.LayerTree Class Reference

Public Member Functions

 constructor (document)
 Constructor, from a PDF document. More...
 
 GetDict ()
 Get the dictionary of current object. More...
 
 GetOCGs ()
 Get the "OCGs" PDF array from current object. More...
 
 GetRootNode ()
 Get the root layer node. More...
 
 IsEmpty ()
 Check whether current object is empty or not. More...
 
 SetBaseState (state)
 Set the base state for all layers in the default configuration. More...
 

Static Public Attributes

static e_StateOFF
 The state is OFF.
 
static e_StateON
 Enumeration for PDF layer base state. More...
 
static e_StateUnchanged
 The state is unchanged.
 
static e_StateUndefined
 The state is undefined.
 

Detailed Description

PDF layer nodes are stored in a PDF layer tree. If user wants to retrieve a layer node, user must construct a layer tree object from a PDF document first and then call function FSDK.LayerTree.GetRootNode to get the root layer node of the whole layer tree. Then, user can enumerate all the nodes in the layer tree from the root layer node.

See also
FSDK.LayerNode

Member Function Documentation

◆ constructor()

FSDK.LayerTree.constructor ( document  )

Constructor, from a PDF document.

The constructed layer tree object can be associated with existed layer tree in PDF document. If there is no layer tree in PDF document which can be judged by functoin FSDK.PDFDoc.HasLayer, the constructed layer tree object will build layer related dictionary.

Parameters
[in]documentA valid PDF document object.

◆ GetDict()

FSDK.LayerTree.GetDict ( )

Get the dictionary of current object.

Note
Please refer to "Optional Content Properties Dictionary" in <PDF Reference 1.7> P375 for more details.
Returns
The dictionary of current object. If there is any error, this function will return null.

◆ GetOCGs()

FSDK.LayerTree.GetOCGs ( )

Get the "OCGs" PDF array from current object.

Note
Please refer to "Optional Content Properties Dictionary" in <PDF Reference 1.7> P375 for more details.
Returns
The "OCGs" PDF array. If there is no "OCGs" entry or any error occurs, this function will return null.

◆ GetRootNode()

FSDK.LayerTree.GetRootNode ( )

Get the root layer node.

After getting the root layer node, user can enumerate all layer nodes in current layer tree by functions of class LayerNode.

Returns
Root layer node.

◆ IsEmpty()

FSDK.LayerTree.IsEmpty ( )

Check whether current object is empty or not.

When the current object is empty, that means current object is useless.

Returns
true means current object is empty, while false means not.

◆ SetBaseState()

FSDK.LayerTree.SetBaseState ( state  )

Set the base state for all layers in the default configuration.

If user wants the new state to have effect on rendering result, please construct a new layer context object after this function succeeds, and then use the new LayerContext to Renderer to do rendering.

Parameters
[in]stateLayer usage state. Please refer to values starting from FSDK.LayerTree.e_StateON and this should be one of these values except FSDK.LayerTree.e_StateUndefined.
Returns
true means success, while false means failure.

Member Data Documentation

◆ e_StateON

FSDK.LayerTree.e_StateON
static

Enumeration for PDF layer base state.

Values of this enumeration should be used alone.

The state is ON.