本文實例為大家分享了Android實現系統打印的具體代碼，供大家參考，具體內容如下
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);} 可以在應用的菜單欄中調用該方法，當printBitmap()方法調用時，Android系統的打印界面
會彈出，用戶可以設置一些參數，然后進行打印或取消。
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函數第二個參數為繼承了抽象類PrintDocumentAdapter 的適配器類，第三個參數為 PrintAttributes對象，
可以用來設置一些打印時的屬性。
2.創建打印適配器類
打印適配器與Android系統的打印框架進行交互，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：關鍵方法有onLayout()和onWrite()，這些方法默認都是在主線程中調用，因此如果打印過程比較耗時，應該在后臺線程中進行。
3.覆蓋onLayout()方法
在onLayout()方法中，你的適配器需要告訴系統框架文本類型，總頁數等信息，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（）方法的執行有完成，取消，和失敗三種結果，你必須通過調用 PrintDocumentAdapter.LayoutResultCallback類的適當回調方法表明執行結果， onLayoutFinished()方法的布爾型參數指示布局內容是否已經改變。
onLayout()方法的主要任務就是計算在新的設置下，需要打印的頁數，如通過打印的方向決定頁數：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
當需要將打印結果輸出到文件中時，系統會調用onWrite（）方法，該方法的參數指明要打印的頁以及結果寫入的文件，你的方法實現需要將頁面的內容寫入到一個多頁面的PDF文檔中，當這個過程完成時，需要調用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()方法實現：
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容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網。
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