本文實(shí)例為大家分享了Android實(shí)現(xiàn)系統(tǒng)打印的具體代碼，供大家參考，具體內(nèi)容如下
一、打印圖片
使用PrintHelper類，如：
private void doPhotoPrint() { PrintHelper photoPrinter = new PrintHelper(getActivity()); photoPrinter.setScaleMode(PrintHelper.SCALE_MODE_FIT); Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.droids); photoPrinter.printBitmap("droids.jpg - test print", bitmap);} 可以在應(yīng)用的菜單欄中調(diào)用該方法，當(dāng)printBitmap()方法調(diào)用時(shí)，Android系統(tǒng)的打印界面
會(huì)彈出，用戶可以設(shè)置一些參數(shù)，然后進(jìn)行打印或取消。
二、打印自定義文檔
1.連接到PrintManager類：
private void doPrint() { // Get a PrintManager instance PrintManager printManager = (PrintManager) getActivity() .getSystemService(Context.PRINT_SERVICE); // Set job name, which will be displayed in the print queue String jobName = getActivity().getString(R.string.app_name) + " Document"; // Start a print job, passing in a PrintDocumentAdapter implementation // to handle the generation of a print document printManager.print(jobName, new MyPrintDocumentAdapter(getActivity()), null); //}注：print函數(shù)第二個(gè)參數(shù)為繼承了抽象類PrintDocumentAdapter 的適配器類，第三個(gè)參數(shù)為 PrintAttributes對(duì)象，
可以用來設(shè)置一些打印時(shí)的屬性。
2.創(chuàng)建打印適配器類
打印適配器與Android系統(tǒng)的打印框架進(jìn)行交互，處理打印的生命周期方法。打印過程主要有以下生命周期方法：
注：關(guān)鍵方法有onLayout()和onWrite()，這些方法默認(rèn)都是在主線程中調(diào)用，因此如果打印過程比較耗時(shí)，應(yīng)該在后臺(tái)線程中進(jìn)行。
3.覆蓋onLayout()方法
在onLayout()方法中，你的適配器需要告訴系統(tǒng)框架文本類型，總頁數(shù)等信息，如：
@Overridepublic void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, CancellationSignal cancellationSignal, LayoutResultCallback callback, Bundle metadata) { // Create a new PdfDocument with the requested page attributes mPdfDocument = new PrintedPdfDocument(getActivity(), newAttributes); // Respond to cancellation request if (cancellationSignal.isCancelled() ) { callback.onLayoutCancelled(); return; } // Compute the expected number of printed pages int pages = computePageCount(newAttributes); if (pages > 0) { // Return print information to print framework PrintDocumentInfo info = new PrintDocumentInfo .Builder("print_output.pdf") .setContentType(PrintDocumentInfo.CONTENT_TYPE_DOCUMENT) .setPageCount(pages); .build(); // Content layout reflow is complete callback.onLayoutFinished(info, true); } else { // Otherwise report an error to the print framework callback.onLayoutFailed("Page count calculation failed."); }}注：onLayout（）方法的執(zhí)行有完成，取消，和失敗三種結(jié)果，你必須通過調(diào)用 PrintDocumentAdapter.LayoutResultCallback類的適當(dāng)回調(diào)方法表明執(zhí)行結(jié)果， onLayoutFinished()方法的布爾型參數(shù)指示布局內(nèi)容是否已經(jīng)改變。
onLayout()方法的主要任務(wù)就是計(jì)算在新的設(shè)置下，需要打印的頁數(shù)，如通過打印的方向決定頁數(shù)：private int computePageCount(PrintAttributes printAttributes) { int itemsPerPage = 4; // default item count for portrait mode MediaSize pageSize = printAttributes.getMediaSize(); if (!pageSize.isPortrait()) { // Six items per page in landscape orientation itemsPerPage = 6; } // Determine number of print items int printItemCount = getPrintItemCount(); return (int) Math.ceil(printItemCount / itemsPerPage);}4.覆蓋onWrite()方法
當(dāng)需要將打印結(jié)果輸出到文件中時(shí)，系統(tǒng)會(huì)調(diào)用onWrite（）方法，該方法的參數(shù)指明要打印的頁以及結(jié)果寫入的文件，你的方法實(shí)現(xiàn)需要將頁面的內(nèi)容寫入到一個(gè)多頁面的PDF文檔中，當(dāng)這個(gè)過程完成時(shí)，需要調(diào)用onWriteFinished() 方法，如：
@Overridepublic void onWrite(final PageRange[] pageRanges, final ParcelFileDescriptor destination, final CancellationSignal cancellationSignal, final WriteResultCallback callback) { // Iterate over each page of the document, // check if it's in the output range. for (int i = 0; i < totalPages; i++) { // Check to see if this page is in the output range. if (containsPage(pageRanges, i)) { // If so, add it to writtenPagesArray. writtenPagesArray.size() // is used to compute the next output page index. writtenPagesArray.append(writtenPagesArray.size(), i); PdfDocument.Page page = mPdfDocument.startPage(i); // check for cancellation if (cancellationSignal.isCancelled()) { callback.onWriteCancelled(); mPdfDocument.close(); mPdfDocument = null; return; } // Draw page content for printing drawPage(page); // Rendering is complete, so page can be finalized. mPdfDocument.finishPage(page); } } // Write PDF document to file try { mPdfDocument.writeTo(new FileOutputStream( destination.getFileDescriptor())); } catch (IOException e) { callback.onWriteFailed(e.toString()); return; } finally { mPdfDocument.close(); mPdfDocument = null; } PageRange[] writtenPages = computeWrittenPages(); // Signal the print framework the document is complete callback.onWriteFinished(writtenPages); ...}drawPage()方法實(shí)現(xiàn)：
private void drawPage(PdfDocument.Page page) { Canvas canvas = page.getCanvas(); // units are in points (1/72 of an inch) int titleBaseLine = 72; int leftMargin = 54; Paint paint = new Paint(); paint.setColor(Color.BLACK); paint.setTextSize(36); canvas.drawText("Test Title", leftMargin, titleBaseLine, paint); paint.setTextSize(11); canvas.drawText("Test paragraph", leftMargin, titleBaseLine + 25, paint); paint.setColor(Color.BLUE); canvas.drawRect(100, 100, 172, 172, paint);}以上就是本文的全部內(nèi)容，希望對(duì)大家的學(xué)習(xí)有所幫助，也希望大家多多支持VEVB武林網(wǎng)。
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