PdfRenderer
public
final
class
PdfRenderer
extends Object
implements
AutoCloseable
java.lang.Object | |
↳ | android.graphics.pdf.PdfRenderer |
This class enables rendering a PDF document and selecting, searching, fast scrolling, annotations, etc. from Android V. This class is thread safe and can be called by multiple threads however only one thread will be executed at a time as the access is synchronized by internal locking.
If you want to render a PDF, you create a renderer and for every page you want to render, you open the page, render it, and close the page. After you are done with rendering, you close the renderer. After the renderer is closed it should not be used anymore. Note that the pages are rendered one by one, i.e. you can have only a single page opened at any given time.
A typical use of the APIs to render a PDF looks like this:
// create a new renderer PdfRenderer renderer = new PdfRenderer(getSeekableFileDescriptor()); // let us just render all pages final int pageCount = renderer.getPageCount(); for (int i = 0; i < pageCount; i++) { Page page = renderer.openPage(i); // say we render for showing on the screen page.render(mBitmap, null, null, Page.RENDER_MODE_FOR_DISPLAY); // do stuff with the bitmap // close the page page.close(); } // close the renderer renderer.close();
Print preview and print output
If you are using this class to rasterize a PDF for printing or show a print preview, it is recommended that you respect the following contract in order to provide a consistent user experience when seeing a preview and printing, i.e. the user sees a preview that is the same as the printout.
-
Respect the property whether the document would like to be scaled for printing
as per
shouldScaleForPrinting()
. - When scaling a document for printing the aspect ratio should be preserved.
-
Do not inset the content with any margins from the
PrintAttributes
as the application is responsible to render it such that the margins are respected. - If document page size is greater than the printed media size the content should be anchored to the upper left corner of the page for left-to-right locales and top right corner for right-to-left locales.
See also:
Summary
Nested classes | |
---|---|
class |
PdfRenderer.Page
This class represents a PDF document page for rendering. |
Constants | |
---|---|
int |
DOCUMENT_LINEARIZED_TYPE_LINEARIZED
Represents a linearized PDF document. |
int |
DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED
Represents a non-linearized PDF document. |
int |
PDF_FORM_TYPE_ACRO_FORM
Represents a PDF with form fields specified using the AcroForm spec |
int |
PDF_FORM_TYPE_NONE
Represents a PDF without form fields |
int |
PDF_FORM_TYPE_XFA_FOREGROUND
Represents a PDF with form fields specified using the XFAF subset of the XFA spec |
int |
PDF_FORM_TYPE_XFA_FULL
Represents a PDF with form fields specified using the entire XFA spec |
Public constructors | |
---|---|
PdfRenderer(ParcelFileDescriptor fileDescriptor)
Creates a new instance. |
|
PdfRenderer(ParcelFileDescriptor fileDescriptor, LoadParams params)
Creates a new instance of PdfRenderer class. |
Public methods | |
---|---|
void
|
close()
Closes this renderer. |
int
|
getDocumentLinearizationType()
Gets the type of the PDF document. |
int
|
getPageCount()
Gets the number of pages in the document. |
int
|
getPdfFormType()
Returns the form type of the loaded PDF |
PdfRenderer.Page
|
openPage(int index)
Opens a page for rendering. |
boolean
|
shouldScaleForPrinting()
Gets whether the document prefers to be scaled for printing. |
void
|
write(ParcelFileDescriptor destination, boolean removePasswordProtection)
Saves the current state of the loaded PDF document to the given writable
|
Protected methods | |
---|---|
void
|
finalize()
Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. |
Inherited methods | |
---|---|
Constants
DOCUMENT_LINEARIZED_TYPE_LINEARIZED
public static final int DOCUMENT_LINEARIZED_TYPE_LINEARIZED
Represents a linearized PDF document.
Constant Value: 1 (0x00000001)
DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED
public static final int DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED
Represents a non-linearized PDF document.
Constant Value: 0 (0x00000000)
PDF_FORM_TYPE_ACRO_FORM
public static final int PDF_FORM_TYPE_ACRO_FORM
Represents a PDF with form fields specified using the AcroForm spec
Constant Value: 1 (0x00000001)
PDF_FORM_TYPE_NONE
public static final int PDF_FORM_TYPE_NONE
Represents a PDF without form fields
Constant Value: 0 (0x00000000)
PDF_FORM_TYPE_XFA_FOREGROUND
public static final int PDF_FORM_TYPE_XFA_FOREGROUND
Represents a PDF with form fields specified using the XFAF subset of the XFA spec
Constant Value: 3 (0x00000003)
PDF_FORM_TYPE_XFA_FULL
public static final int PDF_FORM_TYPE_XFA_FULL
Represents a PDF with form fields specified using the entire XFA spec
Constant Value: 2 (0x00000002)
Public constructors
PdfRenderer
public PdfRenderer (ParcelFileDescriptor fileDescriptor)
Creates a new instance.
Note: The provided file descriptor must be seekable, i.e. its data being randomly accessed, e.g. pointing to a file.
Note: This class takes ownership of the passed in file descriptor and is responsible for closing it when the renderer is closed.
If the file is from an untrusted source it is recommended to run the renderer in a separate,
isolated process with minimal permissions to limit the impact of security exploits.
Note: The constructor should be instantiated on the
ERROR(/android.annotation.WorkerThread)
as it can be long-running while loading the
document.
Parameters | |
---|---|
fileDescriptor |
ParcelFileDescriptor : Seekable file descriptor to read from.
This value cannot be null . |
Throws | |
---|---|
IOException |
If an error occurs while reading the file. |
SecurityException |
If the file requires a password or the security scheme is not supported. |
IllegalArgumentException |
If the ParcelFileDescriptor is not seekable. |
NullPointerException |
If the file descriptor is null. |
PdfRenderer
public PdfRenderer (ParcelFileDescriptor fileDescriptor, LoadParams params)
Creates a new instance of PdfRenderer class.
Note: The provided file descriptor must be seekable,
i.e. its data being randomly accessed, e.g. pointing to a file. If the password passed in
LoadParams
is incorrect, the
PdfRenderer
will throw a SecurityException
.
Note: This class takes ownership of the passed in file descriptor and is responsible for closing it when the renderer is closed.
If the file is from an untrusted source it is recommended to run the renderer in a separate,
isolated process with minimal permissions to limit the impact of security exploits.
Note: The constructor should be instantiated on the
ERROR(/android.annotation.WorkerThread)
as it can be long-running while loading the document.
Parameters | |
---|---|
fileDescriptor |
ParcelFileDescriptor : Seekable file descriptor to read from.
This value cannot be null . |
params |
LoadParams : Instance of LoadParams specifying params for loading PDF
document.
This value cannot be null . |
Throws | |
---|---|
IOException |
If an error occurs while reading the file. |
SecurityException |
If the file requires a password or the security scheme is not supported by the renderer. |
IllegalArgumentException |
If the ParcelFileDescriptor is not seekable. |
NullPointerException |
If the file descriptor or load params is null. |
Public methods
close
public void close ()
Closes this renderer. You should not use this instance after this method is called.
Throws | |
---|---|
IllegalStateException |
If close() is called before invoking this or if any
page is opened and not closed |
See also:
getDocumentLinearizationType
public int getDocumentLinearizationType ()
Gets the type of the PDF document.
Returns | |
---|---|
int |
The PDF document type.
Value is DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED , or DOCUMENT_LINEARIZED_TYPE_LINEARIZED |
Throws | |
---|---|
IllegalStateException |
If close() is called before invoking this. |
getPageCount
public int getPageCount ()
Gets the number of pages in the document.
Returns | |
---|---|
int |
The page count. Value is 0 or greater |
Throws | |
---|---|
IllegalStateException |
If close() is called before invoking this. |
getPdfFormType
public int getPdfFormType ()
Returns the form type of the loaded PDF
Returns | |
---|---|
int |
Value is PDF_FORM_TYPE_NONE , PDF_FORM_TYPE_ACRO_FORM , PDF_FORM_TYPE_XFA_FULL , or PDF_FORM_TYPE_XFA_FOREGROUND |
Throws | |
---|---|
IllegalStateException |
if the renderer is closed |
IllegalArgumentException |
if an unexpected PDF form type is returned |
openPage
public PdfRenderer.Page openPage (int index)
Opens a page for rendering.
Parameters | |
---|---|
index |
int : The page index to open, starting from index 0.
Value is 0 or greater |
Returns | |
---|---|
PdfRenderer.Page |
A page that can be rendered.
This value cannot be null . |
Throws | |
---|---|
IllegalStateException |
If close() is called before invoking this. |
IllegalArgumentException |
If the page number is less than 0 or greater than or equal to the total page count. |
See also:
shouldScaleForPrinting
public boolean shouldScaleForPrinting ()
Gets whether the document prefers to be scaled for printing. You should take this info account if the document is rendered for printing and the target media size differs from the page size.
Returns | |
---|---|
boolean |
If to scale the document. |
Throws | |
---|---|
IllegalStateException |
If close() is called before invoking this. |
write
public void write (ParcelFileDescriptor destination, boolean removePasswordProtection)
Saves the current state of the loaded PDF document to the given writable
ParcelFileDescriptor
. If the document is password-protected then setting
removePasswordProtection
removes the protection before saving. The PDF document
should already be decrypted with the correct password before writing. Useful for printing or
sharing.
Note: This method closes the provided file descriptor.
Parameters | |
---|---|
destination |
ParcelFileDescriptor : The writable ParcelFileDescriptor
This value cannot be null . |
removePasswordProtection |
boolean : If true, removes password protection from the PDF before
saving. |
Throws | |
---|---|
IOException |
If there's a write error, or if 'removePasswordSecurity' is
true but the document remains encrypted. |
IllegalStateException |
If close() is called before invoking this. |
Protected methods
finalize
protected void finalize ()
Called by the garbage collector on an object when garbage collection
determines that there are no more references to the object.
A subclass overrides the finalize
method to dispose of
system resources or to perform other cleanup.
The general contract of finalize
is that it is invoked
if and when the Java virtual
machine has determined that there is no longer any
means by which this object can be accessed by any thread that has
not yet died, except as a result of an action taken by the
finalization of some other object or class which is ready to be
finalized. The finalize
method may take any action, including
making this object available again to other threads; the usual purpose
of finalize
, however, is to perform cleanup actions before
the object is irrevocably discarded. For example, the finalize method
for an object that represents an input/output connection might perform
explicit I/O transactions to break the connection before the object is
permanently discarded.
The finalize
method of class Object
performs no
special action; it simply returns normally. Subclasses of
Object
may override this definition.
The Java programming language does not guarantee which thread will
invoke the finalize
method for any given object. It is
guaranteed, however, that the thread that invokes finalize will not
be holding any user-visible synchronization locks when finalize is
invoked. If an uncaught exception is thrown by the finalize method,
the exception is ignored and finalization of that object terminates.
After the finalize
method has been invoked for an object, no
further action is taken until the Java virtual machine has again
determined that there is no longer any means by which this object can
be accessed by any thread that has not yet died, including possible
actions by other objects or classes which are ready to be finalized,
at which point the object may be discarded.
The finalize
method is never invoked more than once by a Java
virtual machine for any given object.
Any exception thrown by the finalize
method causes
the finalization of this object to be halted, but is otherwise
ignored.
Throws | |
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Throwable |
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Last updated 2024-06-18 UTC.