如何使用 Android 4.4 打印框架打印 PDF [关闭]

Question

如何使用 Android 4.4 打印框架打印已下载的​​ PDF？

我查看了开发者文档。但没有运气。任何示例都会有所帮助

Answer 1

在谷歌上花了几个小时后，我找到了解决方案。

PrintManager printManager = (PrintManager) this.getSystemService(Context.PRINT_SERVICE);
String jobName = this.getString(R.string.app_name) + " Document";
printManager.print(jobName, pda, null);

PrintDocumentAdapter pda = new PrintDocumentAdapter(){

    @Override
    public void onWrite(PageRange[] pages, ParcelFileDescriptor destination, CancellationSignal cancellationSignal, WriteResultCallback callback){
        InputStream input = null;
        OutputStream output = null;

        try {

            input = new FileInputStream(file to print);
            output = new FileOutputStream(destination.getFileDescriptor());

            byte[] buf = new byte[1024];
            int bytesRead;

            while ((bytesRead = input.read(buf)) > 0) {
                 output.write(buf, 0, bytesRead);
            }

            callback.onWriteFinished(new PageRange[]{PageRange.ALL_PAGES});

        } catch (FileNotFoundException ee){
            //Catch exception
        } catch (Exception e) {
            //Catch exception
        } finally {
            try {
                input.close();
                output.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    @Override
    public void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, CancellationSignal cancellationSignal, LayoutResultCallback callback, Bundle extras){

        if (cancellationSignal.isCanceled()) {
            callback.onLayoutCancelled();
            return;
        }


        PrintDocumentInfo pdi = new PrintDocumentInfo.Builder("Name of file").setContentType(PrintDocumentInfo.CONTENT_TYPE_DOCUMENT).build();

        callback.onLayoutFinished(pdi, true);
    }
};