Printing Frameworkandroid.print

The gist of it

The gist of it

PrintManager

Prerequisites

SDK platform 19

SDK build-tools 19 or later

Something to print with

A Google Cloud Print Ready printer

A printer shared through Google Cloud Print

Print to PDF

ApiDemos

[sdk]/sampes/android-19/legacy/ApiDemos

PrintManager printManager = (PrintManager) context.getSystemService(Context.PRINT_SERVICE);

PrintJob printJob = printManager.print( printJobName, documentAdapter, attributes);

PrintManager

Name for the print job(shown to the user)

Adapter that emits the document

Default print job attributes

PrintDocumentAdapter documentAdapter =

// Directly from an existing WebView webView.createPrintDocumentAdapter();

PrintDocumentAdapterWeb pages

// Create a WebView and start printing when its readyWebView webView = new WebView(context);

webView.setWebViewClient(new WebViewClient() { @Override public void onPageFinished( WebView webView, String url) { // Print to it as before PrintDocumentAdapter documentAdapter = webView.createPrintDocumentAdapter(); }});

webView.loadUrl(url);

PrintDocumentAdapterWeb pages

PrintDocumentAdapter documentAdapter =

// Define a custom print adapter

new MyPrintDocumentAdapter(context);

PrintDocumentAdapterCustom documents

Custom Print Adapters

Events:

onStart()

Print process has begun.

onLayout()

A print setting has changed and the layout of the pages needs to be computed.

Must return expected number of pages.

onWrite()

Render printed pages into a file.

onFinish()

Print process has ended.

Custom Print AdaptersonLayout()

public void onLayout( final PrintAttributes oldAttributes, final PrintAttributes newAttributes, final CancellationSignal cancellationSignal, final LayoutResultCallback callback, final Bundle metadata) {

}

onLayoutFinished( PrintDocumentInfo, boolean)

onLayoutFailed(CharSequence)

onLayoutCancelled()

CONTRACT

Custom Print AdaptersonLayout()

Create a document for printing:

PrintedPdfDocument document = new PrintedPdfDocument(context, newAttributes);

Compute the number of pages using PrintAttributes

Return print information to the print framework:

PrintDocumentInfo info = new PrintDocumentInfo .Builder("print_output.pdf") .setContentType( PrintDocumentInfo.CONTENT_TYPE_DOCUMENT) .setPageCount(pages); .build(); callback.onLayoutFinished(info, true);

Wait for the print framework to invoke onWrite()

Custom Print AdaptersonWrite()

public void onWrite( final PageRange[] pages, final ParcelFileDescriptor destination, final CancellationSignal cancellationSignal, final WriteResultCallback callback) {

}

onWriteFinished(PageRange[])

onWriteFailed(CharSequence)

onWriteCancelled()

CONTRACT

Custom Print AdaptersonWrite()

Start writing a page:

Page page = document.startPage(pageNumber);

Draw onto the page canvas:

page.getCanvas();

Note that elements are specified in points (1/72 inch)

Finish writing the page:

document.finishPage(page);

Inform WriteResultCallback of the PageRange[] printed

Custom Print AdaptersCaveats

If you need a screen context, remember that the printer and screen densities differ!

Obtain the printer density:

printerDensity = Math.max( newAttributes.getResolution().getHorizontalDpi(), newAttributes.getResolution().getVerticalDpi());

Create a new Context to cope with a different Configuration:

Configuration configuration = new Configuration(); configuration.densityDpi = printerDensity; printContext = createConfigurationContext( configuration);

Use this context for creating new views:

View view = new LinearLayout(printContext); view.draw(page.getCanvas());

PrintHelper printHelper = new PrintHelper(context);

// Instruct how the content should scaleprintHelper.setScaleMode(PrintHelper.SCALE_MODE_FIT);

// Get the bitmap for the ImageView's drawableBitmap bitmap = ((BitmapDrawable) mImageView.getDrawable()).getBitmap();

// Print the bitmapprintHelper.printBitmap("Print Bitmap", bitmap);

PrintHelper

Happy printing!