README.md

esc_pos_printer

Printing Method.

There are two methods to print receipt.

1. Using the widget method: The widget method generates an image from the flutter widget and prints generated images. This method is encouraged because it can print in an arbitrary format. For example, column, row, image, text in various languages, divider, underline, struck text, receipt border, QR code, and barcode. If we can render it on a device screen, then it can be printed. But the drawback is the print result on the dot matrix printer is not very good, see the table below. If the print quality for dot matrix printing is required, the developer needs to print using the text command
2. Using text command method: Text commands rely on proper code table mapping, so you need to map the code table for the new printer correctly according to esc_pos_utils readme.md. Note: This method is a legacy method and should not be used if at all possible.

Quickstart

For full example usage, See example folder

General procedure is to

1. Discover

PosPrinter.discover()

2. Connect

PosPrinter.connect()

3. Print widget

PosPrinter.widget()

4. Cut

PosPrinter.cut()

5. Pop drawer

PosPrinter.popDrawer()

6. Transmit data to printer

PosPrinter.transmit()

API Reference

Function Prototype	Return value
PosPrinter.discover({bool onlyKnownProfile = true, PosPrinterInterface interface = PosPrinterInterface.All})	Future<List<dynamic>>

• Description: List discovered printer
• Parameters:
  • onlyKnownProfile: true if you want to only discover printer that supported by the library
  • interface: POS printer inteface to discover

---

Function Prototype	Return value
PosPrinter.connect(dynamic printer,{String? networkPrinterProfile, required GlobalKey globalKey})	Future<PosPrinterStatus>

• Description: connect to the printer
• Parameters:
  • printer: obtained from

    PosPrinter.discover()

  • networkPrinterProfile: required for EscPosNetworkPrinter, obtained from

    PosPrinter.availableProfile

  • globalKey: use for Widget image capturing. Application developer must pass the same globalKey in ReceiptWidget constructor like this

    ReceiptWidget(globalKey: globalKey,child: ReceiptData())

---

Function Prototype	Return value
PosPrinter.widget()	Future

• Description: print the ReceiptWidget that construct with the same globalKey used when connect with

  PosPrinter.connect()

---

Function Prototype	Return value
PosPrinter.cut({PosCutMode mode = PosCutMode.full})	Future<Void>

• Description: cut the paper
• Parameters:
  • mode: cut mode. Only have two possibilities, partial cut and full cut

---

Function Prototype	Return value
PosPrinter.popDrawer()	void

• Description: pop the drawer

---

Function Prototype	Return value
PosPrinter.transmit()	Future<PosPrinterStatus>

• Description: transmit generated commands to connected printer

Implementation notes

• An unsupported printer can be discovered by

// The library will load the default profile when connecting to an unsupported printer. So it will likely not work.
// Be aware that not only POS Printer will be discovered by this method.
// The return value will include other types of devices for that interface.
PosPrinter.discover(onlyKnownProfile: false)

• For ESC/POS Network printer

  • Unlike other interface, Network interface cannot retrieve information from a printer, so the library cannot automatically load correct a profile. An application developer must prompt user to manually load a profile. See PosPrinter.connect() for more details.

• For Star Micronics printer

  • This library should work gracefully with every Star Micronics printer model on every interface without a profile support, due to portability of StarPrnt SDK

Tested Printer.

For full list of verified tested printer, see capabilities.json

Model	Type	Paper Size	Receipt Image
Xprinter XP-N160I	Thermal Printer	80mm
Xprinter XP-58IIH	Thermal Printer	58mm
EPSON U02III	Dot Matrix Printer	80mm
XPrinter-76	Dot Matrix Printer	80mm
Star Micronics TSP100III	Thermal Printer	80mm