nativescript-hprt v0.9.7

Nativescript HPRT Thermal Bluetooth Printer

This plugin uses HPRT SDK for Android and iOS (coming soon) from HPRT. At this moment it is tested on mobile bluetooth thermal printers that use 57mm (2.24") rolls. The SDK supports also wifi and other printer features that are not included (yet), we are open for PRs and contributions.

Installation

tns plugin add nativescript-hprt

Demo

You can find demo app here https://github.com/krushkamx/nativescript-hprt-demo

API

Importing the plugin

import { Component, OnInit } from "@angular/core";
import { Hprt, HPRTPrinter } from "nativescript-hprt";

export class YourClass implements OnInit {
    private hprt: Hprt;
  
    constructor() {
        this.hprt = new Hprt();
    }

    ngOnInit(): void {
        
        // Optional, you can enable bluetooth at init (Android only)
        this.enableBluetooth();

    }
}

enableBluetooth

Enables bluetooth if it's turned off, it receives timout value, at this moment it is timeout after which this promise resolves, will try to make automatic. You can call this from ngOnInit() or have a button.

this.hprt.enableBluetooth().then((res) => {
    console.log("BT Enabled", res);
}, (err) => {
    console.log("Error", err);
})

isBluetoothEnabled

Returns true or false depending on bluetooth state

let isBluetoothEnabled = this.hprt.isBluetoothEnabled();

searchPrinters

It returns array of printers discovered.

printers: Array<HPRTPrinter>;

ngOnInit() {    
    this.printers = [];
}

this.hprt.searchPrinters().then(printers => {
    this.printers = printers;
});

connect

You should call this after bluetooth is turned on.

this.hprt.connect(printer).then((res) => {
    console.log("Printer connected");
}, (err) => {
    console.log("Connect error", err)
})

disconnect

Disconnect connected printer, no parameter needed.

this.hprt.disconnect().then((res) => {
    console.log("Disconnected");
}, (err) => {
    console.log("error", err)
})

isConnected

Returns true or false if printer is connected. Useful to call before you perform some print action, so you can connect to printer automatically or manually.

let isConnected = this.hprt.isConnected();

Printing API

You should call this after you've connected to printer

printTextSimple

Prints simple text, default styles.

this.hprt.printTextSimple("Hello world");

printText

Advanced text printing

this.hprt.printText("Hello world", 1, 48, 0);

printTextDouble

Prints double size text

this.hprt.printTextDouble("Hello world");

printTextDoubleHeight

Prints double height text

this.hprt.printTextDoubleHeight("Hello world");

printTextDoubleWidth

Prints double width text

this.hprt.printTextDoubleWidth("Hello world");

printTextUnderline

Prints underline text

this.hprt.printTextUnderline("Hello world");

printTextBold

Prints text in bold

this.hprt.printTextBold("Hello world");

printTextMini

Prints mini text

this.hprt.printTextMini("Hello world");

printTextWhite

Prints text in white

this.hprt.printTextWhite("Hello world");

printTextLeft

Prints left text

this.hprt.printTextLeft("Hello world");

printTextCenter

Prints center text

this.hprt.printTextCenter("Hello world");

printTextRight

Prints right text

this.hprt.printTextRight("Hello world");

Helpers API

newLine

Adds lines (breaks), useful at the end of receipt when you want to leave space to cut it.

this.hprt.newLine(3);

horizontalLine

Adds horizontal line (-------) in 32 characters.

this.hprt.horizontalLine();

Working with workers

Add enable-bluetooth.js to app/workers with this code:

global.onmessage = function(msg) {

    var result = enableBluetooth();

    global.postMessage(result);
}

function enableBluetooth() {
    let mBluetoothAdapter = android.bluetooth.BluetoothAdapter.getDefaultAdapter();

    if (mBluetoothAdapter == null) {
        return { success: false, message: "Bluetooth NOT support", enabled: false}
    }
    else {
        if (mBluetoothAdapter.isEnabled()) {
            if (mBluetoothAdapter.isDiscovering()) {
                return { success: true, message: "Bluetooth is currently in device discovery process.", enabled: false};
            } else {
                return { success: true, message: "Bluetooth is enabled", enabled: true}
            }
        }
        else {
            mBluetoothAdapter.enable();
            return { success: true, message: "", enabled: false};
        }
    }

}

Add connect-printer.js to app/workers with this code:

global.onmessage = function(msg) {
    var request = msg.data;
    var port = request.port;

    var result = connectPrinter(port);

    global.postMessage(result);
}

function connectPrinter(port) {
    let isPortOpen = HPRTAndroidSDK.HPRTPrinterHelper.PortOpen("Bluetooth,"+port.portName);
    
    return isPortOpen;
}

Include workers in your webpack build

Add copying workers in your webpack build

new CopyWebpackPlugin([
    { from: { glob: "*.css" } },
    { from: { glob: "assets/*.css" } },
    { from: { glob: "workers/**" } }, // <-- Add this line to your CopyWebpackPlugin config in webpack.config.js
    { from: { glob: "fonts/**" } },
    { from: { glob: "**/*.jpg" } },
    { from: { glob: "**/*.png" } },
], { ignore: [`${relative(appPath, appResourcesFullPath)}/**`] }),

Tested with printers

• HPRT mobile printers
• G00JPRT
• Bixolon SPP-R200III
• Xprinter P300 (58mm)
• Let us know if works with some other thermal mobile printer

Tested with Android phones

• Samsung S3, Android 4.4
• Redmi 4A, Android 6
• Redmi 4A, Android 7