flutter_zpl_printer 0.1.0

Discover, connect to, and print on Zebra ZPL label printers over Bluetooth LE, Wi-Fi/TCP, and USB. Pure-Dart protocol stack, no Link-OS SDK required.

0.1.0

Breaking: full rewrite. The plugin no longer wraps Zebra's Link-OS SDK. It now ships a pure-Dart protocol stack (SGD, ZPL ~HS status, Zebra BLE GATT, USB printer class) with small native shims only where the OS requires them (USB enumeration and permissions). You no longer need to copy proprietary libZSDK_API.a / ZSDK_ANDROID_API.jar binaries into the plugin.

Added

• Three transports, one Connection API
  • Bluetooth LE: BleConnection, MultichannelBleConnection (print + status channels).
  • Wi-Fi / Ethernet: TcpConnection (9100 ZPL, 6101 CPCL), MultichannelTcpConnection (9100 + 9200).
  • USB (experimental, not yet confirmed working on any platform): UsbConnection, UsbDeviceAddress for macOS, Windows, and Android, backed by libusb 1.0.29.
  • ReconnectableConnection decorator with exponential backoff.
• Discovery: DiscoveryService.discoverAll() merges USB, UDP broadcast/multicast, and BLE. Each transport is also available on its own (UsbDiscovery, NetworkDiscovery, BleDiscovery), as is TCP subnet search. UsbHotplugStream.events() reports plug/unplug events.
• ZebraPrinter high-level API: printZpl, getStatus, getSetting / setSetting / doCommand, calibrate, printConfigurationLabel, getMetadata, printImage, file and format storage, and more.
• Utilities: Sgd, FileUtil, FormatUtil, FontUtil, AlertUtil, ProfileUtil, FirmwareUtil, GraphicsUtil (GRF / Z64 image encoding), ZplSanitizer.
• Typed errors: ConnectionException plus 11 USB-specific subclasses (UsbPermissionDeniedException, UsbDeviceBusyException with a remediation hint, and others).
• PrinterSgdKey: a catalog of verified Zebra SGD keys, grouped by category.
• Test support: package:flutter_zpl_printer/flutter_zpl_printer_testing.dart exports FakeUsbPlatform.
• New platforms: macOS and Windows.
• Integration guide based on a production app.

Removed

The 0.0.1 API is gone. Migration:

0.0.1	0.1.0
FlutterZplPrinter().startDiscovery() + onPrinterFound	DiscoveryService.discoverAll() (a Stream<DiscoveredPrinter>)
connect(address, ConnectionType.bluetooth)	ZebraPrinter.connect(BleConnection(deviceId))
connect(address, ConnectionType.wifi)	ZebraPrinter.connect(TcpConnection.zpl(ip))
printZpl(zpl)	printer.printZpl(zpl)
getStatus()	printer.getStatus()
getSettings()	printer.getSetting('allcv') (raw text), or printer.getMetadata()
disconnect()	printer.disconnect()

Classic Bluetooth (iOS MFi / Android SPP) is not supported in 0.1.0. Use Bluetooth LE, which Zebra printers with Bluetooth 4.0 or later support.

Platform status

Tested on hardware with Zebra printers:

Transport	iOS	macOS	Windows	Android
Bluetooth LE	✅	✅	✅	✅
Wi-Fi / TCP	✅	✅	✅	✅
USB	not possible (no USB host on iOS)	not tested	❌ fails in testing	not tested

Known issues

• Windows USB failed when tested with Zebra printers; the cause is not confirmed yet. libusb-1.0.dll is not bundled, printers bound to the ZDesigner/usbprint driver can't be claimed, and the open path assumes fixed endpoints. Plug/unplug events are not emitted on Windows. Bluetooth LE and Wi-Fi work on Windows. Details and workarounds: Known issues → Windows USB. Please report results on the issue tracker.
• Android USB needs libusb-1.0.so built per ABI. The package does not ship it yet, so Android USB calls fail with UsbLibLoadException.

0.0.1

• Initial release.
• Printer discovery via Bluetooth MFi and Wi-Fi.
• Connect/disconnect to Zebra ZPL printers.
• Raw ZPL payload printing.
• Printer hardware status queries.
• Retrieve all printer settings (getSettings).
• Cross-platform error codes for structured error handling.