PdfRenderer
class PdfRenderer : AutoCloseable
kotlin.Any | |
↳ | 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
android.print.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.
Summary
Nested classes | |
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This class represents a PDF document page for rendering. |
Constants | |
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static Int |
Represents a linearized PDF document. |
static Int |
Represents a non-linearized PDF document. |
static Int |
Represents a PDF with form fields specified using the AcroForm spec |
static Int |
Represents a PDF without form fields |
static Int |
Represents a PDF with form fields specified using the XFAF subset of the XFA spec |
static Int |
Represents a PDF with form fields specified using the entire XFA spec |
Public constructors | |
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PdfRenderer(fileDescriptor: ParcelFileDescriptor) Creates a new instance. |
|
PdfRenderer(fileDescriptor: ParcelFileDescriptor, params: LoadParams) Creates a new instance of PdfRenderer class. |
Public methods | |
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Unit |
close() Closes this renderer. |
Int |
Gets the type of the PDF document. |
Int |
Gets the number of pages in the document. |
Int |
Returns the form type of the loaded PDF |
PdfRenderer.Page |
Opens a page for rendering. |
Boolean |
Gets whether the document prefers to be scaled for printing. |
Unit |
write(destination: ParcelFileDescriptor, removePasswordProtection: Boolean) Saves the current state of the loaded PDF document to the given writable |
Protected methods | |
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Unit |
finalize() |
Constants
DOCUMENT_LINEARIZED_TYPE_LINEARIZED
static val DOCUMENT_LINEARIZED_TYPE_LINEARIZED: Int
Represents a linearized PDF document.
Value: 1
DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED
static val DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED: Int
Represents a non-linearized PDF document.
Value: 0
PDF_FORM_TYPE_ACRO_FORM
static val PDF_FORM_TYPE_ACRO_FORM: Int
Represents a PDF with form fields specified using the AcroForm spec
Value: 1
PDF_FORM_TYPE_NONE
static val PDF_FORM_TYPE_NONE: Int
Represents a PDF without form fields
Value: 0
PDF_FORM_TYPE_XFA_FOREGROUND
static val PDF_FORM_TYPE_XFA_FOREGROUND: Int
Represents a PDF with form fields specified using the XFAF subset of the XFA spec
Value: 3
PDF_FORM_TYPE_XFA_FULL
static val PDF_FORM_TYPE_XFA_FULL: Int
Represents a PDF with form fields specified using the entire XFA spec
Value: 2
Public constructors
PdfRenderer
PdfRenderer(fileDescriptor: ParcelFileDescriptor)
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 android.annotation.WorkerThread
as it can be long-running while loading the document.
Parameters | |
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fileDescriptor |
ParcelFileDescriptor: Seekable file descriptor to read from. This value cannot be null . |
Exceptions | |
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java.io.IOException |
If an error occurs while reading the file. |
java.lang.SecurityException |
If the file requires a password or the security scheme is not supported. |
java.lang.IllegalArgumentException |
If the ParcelFileDescriptor is not seekable. |
java.lang.NullPointerException |
If the file descriptor is null. |
PdfRenderer
PdfRenderer(
fileDescriptor: ParcelFileDescriptor,
params: LoadParams)
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 android.graphics.pdf.LoadParams
is incorrect, the android.graphics.pdf.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 android.annotation.WorkerThread
as it can be long-running while loading the document.
Parameters | |
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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 . |
Exceptions | |
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java.io.IOException |
If an error occurs while reading the file. |
java.lang.SecurityException |
If the file requires a password or the security scheme is not supported by the renderer. |
java.lang.IllegalArgumentException |
If the ParcelFileDescriptor is not seekable. |
java.lang.NullPointerException |
If the file descriptor or load params is null. |
Public methods
close
fun close(): Unit
Closes this renderer. You should not use this instance after this method is called.
Exceptions | |
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java.lang.Exception |
if this resource cannot be closed |
java.lang.IllegalStateException |
If close() is called before invoking this or if any page is opened and not closed |
getDocumentLinearizationType
fun getDocumentLinearizationType(): Int
Gets the type of the PDF document.
Return | |
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Int |
The PDF document type. Value is android.graphics.pdf.PdfRenderer#DOCUMENT_LINEARIZED_TYPE_NON_LINEARIZED , or android.graphics.pdf.PdfRenderer#DOCUMENT_LINEARIZED_TYPE_LINEARIZED |
Exceptions | |
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java.lang.IllegalStateException |
If close() is called before invoking this. |
getPageCount
fun getPageCount(): Int
Gets the number of pages in the document.
Return | |
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Int |
The page count. Value is 0 or greater |
Exceptions | |
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java.lang.IllegalStateException |
If close() is called before invoking this. |
getPdfFormType
fun getPdfFormType(): Int
Returns the form type of the loaded PDF
Exceptions | |
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java.lang.IllegalStateException |
if the renderer is closed |
java.lang.IllegalArgumentException |
if an unexpected PDF form type is returned |
openPage
fun openPage(index: Int): PdfRenderer.Page
Opens a page for rendering.
Parameters | |
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index |
Int: The page index to open, starting from index 0. Value is 0 or greater |
Return | |
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PdfRenderer.Page |
A page that can be rendered. This value cannot be null . |
Exceptions | |
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java.lang.IllegalStateException |
If close() is called before invoking this. |
java.lang.IllegalArgumentException |
If the page number is less than 0 or greater than or equal to the total page count. |
shouldScaleForPrinting
fun shouldScaleForPrinting(): Boolean
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.
Return | |
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Boolean |
If to scale the document. |
Exceptions | |
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java.lang.IllegalStateException |
If close() is called before invoking this. |
write
fun write(
destination: ParcelFileDescriptor,
removePasswordProtection: Boolean
): Unit
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 | |
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destination |
ParcelFileDescriptor: The writable ParcelFileDescriptor This value cannot be null . |
removePasswordProtection |
Boolean: If true, removes password protection from the PDF before saving. |
Exceptions | |
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java.io.IOException |
If there's a write error, or if 'removePasswordSecurity' is true but the document remains encrypted. |
java.lang.IllegalStateException |
If close() is called before invoking this. |
Protected methods
finalize
protected fun finalize(): Unit
Exceptions | |
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java.lang.Throwable |
the Exception raised by this method |