@nstudio/nativescript-barcodescanner
v5.0.1
Published
Scan QR/barcodes with your NativeScript app.
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Readme
NativeScript BarcodeScanner
💡 Plugin version 5.0.0+ is compatible with NativeScript 7+ and also supports Mac M1. If you need to target older NativeScript versions, please stick to plugin
nativescript-barcodescanner
3.4.2.
Supported barcode types
iOS and Android
- CODE_39
- CODE_93
- CODE_128
- DATA_MATRIX
- EAN_8
- EAN_13
- ITF (also known as ITF14)
- PDF_417 (on Android only when passed in explicity via
formats
) - QR_CODE
- UPC_A
- UPC_E
Android only
- CODABAR
- MAXICODE
- RSS_14
iOS only
- AZTEC
- CODE_39_MOD_43
- INTERLEAVED_2_OF_5
A note about UPC_A
and EAN_13
When either (or both) of these are specified, both can be returned.
You can check the actual type by inspecting the format
property of the result object.
For details, see #176.
Installation
npm install @nstudio/nativescript-barcodescanner
Embedding the scanner (iOS)
If you need to embed the scanner for Android as well, please consider using the Machine Learning powered Barcode scanner I've added to the ML Kit feature of the NativeScript Firebase plugin!
As you can see, you can style the view any way you like, and even overlay it with an image or button. To recreate the layout above, look at these lines in the demo app.
💡 TIP: If you don't destroy the component/page which embed the scanner (but instead show a modal, or navigate "forward") you can "pause" the scanner (since plugin version 3.4.0). Simply set that
pause
property totrue
when applicable.
XML
<Page xmlns="http://schemas.nativescript.org/tns.xsd" xmlns:Barcode="@nstudio/nativescript-barcodescanner">
Here's an example tag, showing all currently supported options. The property defaults are equal to the scan
function.
<iOS>
<Barcode:BarcodeScannerView
class="scanner-round"
formats="QR_CODE, EAN_13"
beepOnScan="true"
reportDuplicates="true"
preferFrontCamera="false"
pause="{{ pause }}"
scanResult="{{ onScanResult }}" />
</iOS>
Angular
Component / Module:
import { registerElement } from "@nativescript/angular";
registerElement("BarcodeScanner", () => require("@nstudio/nativescript-barcodescanner").BarcodeScannerView);
View:
<BarcodeScanner
class="scanner-round"
formats="QR_CODE, EAN_13"
beepOnScan="true"
reportDuplicates="true"
preferFrontCamera="false"
[pause]="pause"
(scanResult)="onScanResult($event)">
</BarcodeScanner>
Vue
main.ts:
Vue.registerElement('BarcodeScanner', () => require('@nstudio/nativescript-barcodescanner').BarcodeScannerView)
View:
<BarcodeScanner
row="1"
height="300"
formats="QR_CODE, EAN_13, UPC_A"
beepOnScan="true"
reportDuplicates="true"
preferFrontCamera="false"
:pause="pause"
@scanResult="onScanResult"
v-if="isIOS">
</BarcodeScanner>
See 'demo-vue' for details.
iOS runtime permission reason
iOS 10+ requires not only this popup, but also a reason. In this case it's "We'd like to use the Camera ..".
You can provide your own reason for accessing the camera by adding something like this to app/App_Resources/ios/Info.plist
:
<key>NSCameraUsageDescription</key>
<string>My reason justifying fooling around with your camera</string>
To not crash your app in case you forgot to provide the reason this plugin adds an empty reason to the .plist
during build. This value gets overridden by anything you specify yourself.
Usage
Tip: during a scan you can use the volume up/down buttons to toggle the torch.
function: scan (single mode)
TypeScript
import { BarcodeScanner } from "@nstudio/nativescript-barcodescanner";
const barcodescanner = new BarcodeScanner();
barcodescanner.scan({
formats: "QR_CODE, EAN_13",
cancelLabel: "EXIT. Also, try the volume buttons!", // iOS only, default 'Close'
cancelLabelBackgroundColor: "#333333", // iOS only, default '#000000' (black)
message: "Use the volume buttons for extra light", // Android only, default is 'Place a barcode inside the viewfinder rectangle to scan it.'
showFlipCameraButton: true, // default false
preferFrontCamera: false, // default false
showTorchButton: true, // default false
beepOnScan: true, // Play or Suppress beep on scan (default true)
fullScreen: true, // Currently only used on iOS; with iOS 13 modals are no longer shown fullScreen by default, which may be actually preferred. But to use the old fullScreen appearance, set this to 'true'. Default 'false'.
torchOn: false, // launch with the flashlight on (default false)
closeCallback: () => { console.log("Scanner closed")}, // invoked when the scanner was closed (success or abort)
resultDisplayDuration: 500, // Android only, default 1500 (ms), set to 0 to disable echoing the scanned text
orientation: orientation, // Android only, default undefined (sensor-driven orientation), other options: portrait|landscape
openSettingsIfPermissionWasPreviouslyDenied: true, // On iOS you can send the user to the settings app if access was previously denied
presentInRootViewController: true // iOS-only; If you're sure you're not presenting the (non embedded) scanner in a modal, or are experiencing issues with fi. the navigationbar, set this to 'true' and see if it works better for your app (default false).
}).then((result) => {
// Note that this Promise is never invoked when a 'continuousScanCallback' function is provided
alert({
title: "Scan result",
message: "Format: " + result.format + ",\nValue: " + result.text,
okButtonText: "OK"
});
}, (errorMessage) => {
console.log("No scan. " + errorMessage);
}
);
Note that
result.format
above is one of these.
JavaScript
var BarcodeScanner = require("@nstudio/nativescript-barcodescanner").BarcodeScanner;
var barcodescanner = new BarcodeScanner();
barcodescanner.scan({
formats: "QR_CODE,PDF_417", // Pass in of you want to restrict scanning to certain types
cancelLabel: "EXIT. Also, try the volume buttons!", // iOS only, default 'Close'
cancelLabelBackgroundColor: "#333333", // iOS only, default '#000000' (black)
message: "Use the volume buttons for extra light", // Android only, default is 'Place a barcode inside the viewfinder rectangle to scan it.'
showFlipCameraButton: true, // default false
preferFrontCamera: false, // default false
showTorchButton: true, // default false
beepOnScan: true, // Play or Suppress beep on scan (default true)
fullScreen: true, // Currently only used on iOS; with iOS 13 modals are no longer shown fullScreen by default, which may be actually preferred. But to use the old fullScreen appearance, set this to 'true'. Default 'false'.
torchOn: false, // launch with the flashlight on (default false)
closeCallback: function () { console.log("Scanner closed"); }, // invoked when the scanner was closed (success or abort)
resultDisplayDuration: 500, // Android only, default 1500 (ms), set to 0 to disable echoing the scanned text
orientation: "landscape", // Android only, optionally lock the orientation to either "portrait" or "landscape"
openSettingsIfPermissionWasPreviouslyDenied: true // On iOS you can send the user to the settings app if access was previously denied
}).then(
function(result) {
console.log("Scan format: " + result.format);
console.log("Scan text: " + result.text);
},
function(error) {
console.log("No scan: " + error);
}
);
function: scan (bulk / continuous mode)
In this mode the scanner will continuously report scanned codes back to your code,
but it will only be dismissed if the user tells it to, or you call stop
programmatically.
The plugin handles duplicates for you so don't worry about checking those;
every result withing the same scan session is unique unless you set reportDuplicates
to true
.
Here's an example of scanning 3 unique QR codes and then stopping scanning programmatically. You'll notice that the Promise will no longer receive the result as there may be many results:
JavaScript
var count = 0;
barcodescanner.scan({
formats: "QR_CODE",
// this callback will be invoked for every unique scan in realtime!
continuousScanCallback: function (result) {
count++;
console.log(result.format + ": " + result.text + " (count: " + count + ")");
if (count === 3) {
barcodescanner.stop();
}
},
closeCallback: function () { console.log("Scanner closed"); }, // invoked when the scanner was closed
reportDuplicates: false // which is the default
}).then(
function() {
console.log("We're now reporting scan results in 'continuousScanCallback'");
},
function(error) {
console.log("No scan: " + error);
}
);
function: available
Note that the iOS implementation will always return true
at the moment,
on Android we actually check for a camera to be available.
JavaScript
var barcodescanner = require("@nstudio/nativescript-barcodescanner");
barcodescanner.available().then(
function(avail) {
console.log("Available? " + avail);
}
);
function: hasCameraPermission / requestCameraPermission
On Android 6+ you need to request permission to use the camera at runtime when targeting API level 23+.
Even if the uses-permission
tag for the Camera is present in AndroidManifest.xml
.
On iOS 10+ there's something similar going on.
Since version 1.5.0 you can let the plugin handle this for you (if need be a prompt will be shown to the user when the scanner launches), but if for some reason you want to handle permissions yourself you can use these functions.
JavaScript
barcodescanner.hasCameraPermission().then(
function(granted) {
// if this is 'false' you probably want to call 'requestCameraPermission' now
console.log("Has Camera Permission? " + result);
}
);
// if no permission was granted previously this wil open a user consent screen
barcodescanner.requestCameraPermission().then(
function() {
console.log("Camera permission requested");
}
);
Usage with @nativescript/angular
You may have injected the BarcodeScanner
class in your component constructor in the past,
but please don't do that anymore because in release builds you may experience a crash.
So instead of:
// my-component.ts
import { Component, Inject } from '@angular/core';
import { BarcodeScanner } from '@nstudio/nativescript-barcodescanner';
@Component({ ... })
export class MyComponent {
constructor(private barcodeScanner: BarcodeScanner) {
}
//use the barcodescanner wherever you need it. See general usage above.
scanBarcode() {
this.barcodeScanner.scan({ ... });
}
}
Simply do:
// my-component.ts
import { Component, Inject } from '@angular/core';
import { BarcodeScanner } from '@nstudio/nativescript-barcodescanner';
@Component({ ... })
//use the barcodescanner wherever you need it. See general usage above.
scanBarcode() {
new BarcodeScanner().scan({ ... });
}
}
Webpack usage
If you run into an error when Webpacking, open app.module.ts
and add this:
import { BarcodeScanner } from "@nstudio/nativescript-barcodescanner";
export function createBarcodeScanner() {
return new BarcodeScanner();
}
providers: [
{ provide: BarcodeScanner, useFactory: createBarcodeScanner }
]
Troubleshooting
If you get the error TypeError: Cannot read property 'zxing' of undefined
on android, try the following steps:
- Delete the app from your device
- Remove the folder
platforms/android
. This triggers a complete rebuild - run
tns run android
Dependencies / Related Projects
This plugin wraps libaries for Android and iOS to make the barcode scanner easily accessible via a unified API. The Libraries used are:
iOS
Custom Framework to access iOS APIs: https://github.com/EddyVerbruggen/ios-framework-barcodescanner
Android
ZXing: https://github.com/zxing/zxing/releases
As using that library as a direct dependency was not practical, there is a library-project that adopts the sources from ZXing and copiles them into a AAR for usage on android: https://github.com/EddyVerbruggen/barcodescanner-lib-aar/