生成后（PDF）通过手机存储中的推送通知打开PDF文件

Question

我正在我的应用程序中生成发票（PDF）。生成PDF文件后，我需要推送通知。用户单击推送通知时，应通过默认应用程序打开PDF文件。

try
{

    Date date2 = new Date();

    DateFormat sdf = new java.text.SimpleDateFormat("dd-MM-yyyy");
    String time = DateUtils.formatDateTime(thisActivity, date2.getTime(), DateUtils.FORMAT_SHOW_TIME);
    String Date = sdf.format(date2);

    Document document = new Document();
    PdfWriter.getInstance(document, new FileOutputStream(Environment.getExternalStorageDirectory() +"/" + Invoice + "invoice.pdf"));
    document.open();
    document.getPageSize();
    PdfPTable table = new PdfPTable(1);
    PdfPCell cell = new PdfPCell();
    cell.addElement(new Paragraph("test"));
    cell.addElement(new Paragraph("test"));
    cell.addElement(new Paragraph("GSTIN : "+ GST));
    cell.addElement(new Paragraph(test));
    cell.addElement(new Paragraph(Email));
    cell.setPadding(5);
    table.addCell(cell);

    PdfPTable table1 = new PdfPTable(2);
    PdfPTable table2 = new PdfPTable(5);


    PdfPCell cell1 = new PdfPCell();
    cell1.addElement(new Paragraph(ShopName));
    cell1.addElement(new Paragraph(ShopAddress));
    cell1.addElement(new Paragraph(LandMark));

    PdfPCell cell2 = new PdfPCell();
    cell2.addElement(new Paragraph("Billing_Invoice Date     : " + Date));
    cell2.addElement(new Paragraph("Billing_Invoice No : "+ Invoice));
    table1.addCell(cell1);
    table1.addCell(cell2);


    PdfPCell serilno = new PdfPCell(new Phrase("S.NO"));
    PdfPCell description = new PdfPCell(new Phrase("Description"));
    PdfPCell qty = new PdfPCell(new Phrase("Qty"));
    PdfPCell price = new PdfPCell(new Phrase("Price"));
    PdfPCell amount = new PdfPCell(new Phrase("Amount"));
    table2.addCell(serilno);
    table2.addCell(description);
    table2.addCell(qty);
    table2.addCell(price);
    table2.addCell(amount);

    int sNO = 0, qTY = 0, TotalCharges = 0, Price = 0;
    String ProductType, Type, Veriety;

    for (int i = 0; i < DeliverOrderlist.size(); i++){

        sNO = i + 1;

        ProductType = DeliverOrderlist.get(i).getProduct();
        Type = DeliverOrderlist.get(i).getType();
        serilno.addElement(new Paragraph(String.valueOf(sNO)));
        Veriety = DeliverOrderlist.get(i).getVariety();
        qTY = DeliverOrderlist.get(i).getUnitCount();
        qty.addElement(new Paragraph(String.valueOf(qTY)));
        description.addElement(new Paragraph(ProductType + " " + Type + " " + Veriety));

    Price = Integer.parseInt(Billing_InvoiceAdapter.dataList.get(i).getEditTextValue());
        Price = enteredNumber[i];
        price.addElement(new Paragraph(String.valueOf(Price)));
        int result = qTY * Price;
        amount.addElement(new Paragraph(String.valueOf(result)));

            TotalCharges += result;
    }
    table2.addCell(serilno);
    table2.addCell(description);
    table2.addCell(qty);
    table2.addCell(price);
    table2.addCell(amount);
    PdfPTable table3 = new PdfPTable(2);
    PdfPCell TotalValue = new PdfPCell(new Phrase("Total Value"));
    PdfPCell TotalCharge = new PdfPCell(new Phrase("Rs: " + String.valueOf(TotalCharges)));
    TotalCharge.setPaddingLeft(50);
    TotalValue.setPaddingTop(5);
    TotalValue.setPaddingBottom(5);
    TotalCharge.setPaddingTop(5);
    TotalCharge.setPaddingBottom(5);
    table3.addCell(TotalValue);

    table3.addCell(TotalCharge);

    String PricenWrods =   EnglishNumberToWords.convert(TotalCharges);
    PdfPTable table4 = new PdfPTable(1);
    PdfPCell AmtnWords = new PdfPCell(new Phrase("Amount in words : " + PricenWrods + " " +  "only"));
    AmtnWords.setPaddingTop(5);
    AmtnWords.setPaddingBottom(5);
    table4.addCell(AmtnWords);

    document.add(table);
    document.add(table1);
    document.add(table2);
    document.add(table3);
    document.add(table4);

    Toast.makeText(thisActivity, "Invoice Generated!!", Toast.LENGTH_SHORT).show();
    document.close();


}

catch (FileNotFoundException e)
{
    // TODO Auto-generated catch block
    e.printStackTrace();
}
catch (DocumentException e)
{
    // TODO Auto-generated catch block
    e.printStackTrace();
}

这是我生成PDF文件（发票）的方式。谁能帮我这个？预先感谢。