Unofficial Capacitor plugin for ML Kit Barcode Scanning.12
- 🧩 Optional ready-to-use interface without webview customizations
- 🏎️ Extremely fast
- 📷 Scan multiple barcodes at once
- ⏺️ Define detection area
- 🏞️ Reading barcodes from images
- 🔦 Torch and Autofocus support
- 🔋 Supports Android and iOS
For a complete list of supported barcodes, see BarcodeFormat.
A working example can be found here: https://github.com/robingenz/capacitor-mlkit-plugin-demo
Android |
---|
npm install @capacitor-mlkit/barcode-scanning
npx cap sync
This API requires the following permissions be added to your AndroidManifest.xml
before the application
tag:
<!-- To get access to the camera. -->
<uses-permission android:name="android.permission.CAMERA" />
<!-- To get access to the flashlight. -->
<uses-permission android:name="android.permission.FLASHLIGHT"/>
You also need to add the following meta data in the application
tag in your AndroidManifest.xml
:
<meta-data android:name="com.google.mlkit.vision.DEPENDENCIES" android:value="barcode_ui"/>
<!-- To use multiple models: android:value="face,model2,model3" -->
Enable the databinding library by setting the dataBinding
and enabled
build options to true
in your module-level (app-level) Gradle file (usually android/app/build.gradle
):
android {
...
+ buildFeatures {
+ dataBinding true
+ }
+ dataBinding {
+ enabled = true
+ }
}
This plugin will use the following project variables (defined in your app’s variables.gradle
file):
-
$androidxCameraCamera2Version
version ofcom.google.mlkit:barcode-scanning
(default:1.1.0
) -
$androidxCameraCoreVersion
version ofcom.google.mlkit:barcode-scanning
(default:1.1.0
) -
$androidxCameraLifecycleVersion
version ofcom.google.mlkit:barcode-scanning
(default:1.1.0
) -
$androidxCameraViewVersion
version ofcom.google.mlkit:barcode-scanning
(default:1.1.0
) -
$mlkitBarcodeScanningVersion
version ofcom.google.mlkit:barcode-scanning
(default:17.1.0
) -
$playServicesCodeScannerVersion
version ofcom.google.mlkit:barcode-scanning
(default:16.0.0
)
Add the NSCameraUsageDescription
key to the ios/App/App/Info.plist
file, which tells the user why the app needs to use the camera:
+ <key>NSCameraUsageDescription</key>
+ <string>The app enables the scanning of various barcodes.</string>
No configuration required for this plugin.
A working example can be found here: robingenz/capacitor-mlkit-plugin-demo
import {
BarcodeScanner,
BarcodeFormat,
LensFacing,
} from '@capacitor-mlkit/barcode-scanning';
const startScan = async () => {
// The camera is visible behind the WebView, so that you can customize the UI in the WebView.
// However, this means that you have to hide all elements that should not be visible.
// You can find an example in our demo repository.
// In this case we set a class `barcode-scanner-active`, which then contains certain CSS rules for our app.
document.querySelector('body')?.classList.add('barcode-scanner-active');
// Add the `barcodeScanned` listener
const listener = await BarcodeScanner.addListener(
'barcodeScanned',
async result => {
console.log(result.barcode);
},
);
// Start the barcode scanner
await BarcodeScanner.startScan();
};
const stopScan = async () => {
// Make all elements in the WebView visible again
document.querySelector('body')?.classList.remove('barcode-scanner-active');
// Remove all listeners
await BarcodeScanner.removeAllListeners();
// Stop the barcode scanner
await BarcodeScanner.stopScan();
};
const scanSingleBarcode = async () => {
return new Promise(async resolve => {
document.querySelector('body')?.classList.add('barcode-scanner-active');
const listener = await BarcodeScanner.addListener(
'barcodeScanned',
async result => {
await listener.remove();
document
.querySelector('body')
?.classList.remove('barcode-scanner-active');
await BarcodeScanner.stopScan();
resolve(result.barcode);
},
);
await BarcodeScanner.startScan();
});
};
const scan = async () => {
const { barcodes } = await BarcodeScanner.scan({
formats: [BarcodeFormat.QrCode],
});
return barcodes;
};
const isSupported = async () => {
const { supported } = await BarcodeScanner.isSupported();
return supported;
};
const enableTorch = async () => {
await BarcodeScanner.enableTorch();
};
const disableTorch = async () => {
await BarcodeScanner.disableTorch();
};
const toggleTorch = async () => {
await BarcodeScanner.toggleTorch();
};
const isTorchEnabled = async () => {
const { enabled } = await BarcodeScanner.isTorchEnabled();
return enabled;
};
const isTorchAvailable = async () => {
const { available } = await BarcodeScanner.isTorchAvailable();
return available;
};
const setZoomRatio = async () => {
await BarcodeScanner.setZoomRatio({ zoomRatio: 0.5 });
};
const getZoomRatio = async () => {
const { zoomRatio } = await BarcodeScanner.getZoomRatio();
return zoomRatio;
};
const getMinZoomRatio = async () => {
const { zoomRatio } = await BarcodeScanner.getMinZoomRatio();
return zoomRatio;
};
const getMaxZoomRatio = async () => {
const { zoomRatio } = await BarcodeScanner.getMaxZoomRatio();
return zoomRatio;
};
const openSettings = async () => {
await BarcodeScanner.openSettings();
};
const isGoogleBarcodeScannerModuleAvailable = async () => {
const { available } =
await BarcodeScanner.isGoogleBarcodeScannerModuleAvailable();
return available;
};
const installGoogleBarcodeScannerModule = async () => {
await BarcodeScanner.installGoogleBarcodeScannerModule();
};
const checkPermissions = async () => {
const { camera } = await BarcodeScanner.checkPermissions();
return camera;
};
const requestPermissions = async () => {
const { camera } = await BarcodeScanner.requestPermissions();
return camera;
};
An example of the CSS class barcode-scanner-active
with Ionic Framework could be:
// Hide all elements
body.barcode-scanner-active {
visibility: hidden;
--background: transparent;
--ion-background-color: transparent;
}
// Show only the barcode scanner modal
.barcode-scanner-modal {
visibility: visible;
}
@media (prefers-color-scheme: dark) {
.barcode-scanner-modal {
--background: transparent;
--ion-background-color: transparent;
}
}
An example of the CSS class barcode-scanner-active
without Ionic Framework could be:
// Hide all elements
body.barcode-scanner-active {
visibility: hidden;
}
// Show only the barcode scanner modal
.barcode-scanner-modal {
visibility: visible;
}
If you can't see the camera view, make sure all elements in the DOM are not visible or have a transparent background to debug the issue.
startScan(...)
stopScan()
readBarcodesFromImage(...)
scan(...)
isSupported()
enableTorch()
disableTorch()
toggleTorch()
isTorchEnabled()
isTorchAvailable()
setZoomRatio(...)
getZoomRatio()
getMinZoomRatio()
getMaxZoomRatio()
openSettings()
isGoogleBarcodeScannerModuleAvailable()
installGoogleBarcodeScannerModule()
checkPermissions()
requestPermissions()
addListener('barcodeScanned', ...)
addListener('scanError', ...)
addListener('googleBarcodeScannerModuleInstallProgress', ...)
removeAllListeners()
- Interfaces
- Type Aliases
- Enums
startScan(options?: StartScanOptions | undefined) => Promise<void>
Start scanning for barcodes.
Only available on Android and iOS.
Param | Type |
---|---|
options |
StartScanOptions |
Since: 0.0.1
stopScan() => Promise<void>
Stop scanning for barcodes.
Only available on Android and iOS.
Since: 0.0.1
readBarcodesFromImage(options: ReadBarcodesFromImageOptions) => Promise<ReadBarcodesFromImageResult>
Read barcodes from an image.
Only available on Android and iOS.
Param | Type |
---|---|
options |
ReadBarcodesFromImageOptions |
Returns: Promise<ReadBarcodesFromImageResult>
Since: 0.0.1
scan(options?: ScanOptions | undefined) => Promise<ScanResult>
Scan a barcode with a ready-to-use interface without WebView customization.
On Android, this method is only available on devices with Google Play Services installed. Therefore, no camera permission is required.
Attention: Before using this method on Android, first check if the Google Barcode Scanner module is available
by using isGoogleBarcodeScannerModuleAvailable()
.
Only available on Android and iOS.
Param | Type |
---|---|
options |
ScanOptions |
Returns: Promise<ScanResult>
Since: 0.0.1
isSupported() => Promise<IsSupportedResult>
Returns whether or not the barcode scanner is supported.
Available on Android and iOS.
Returns: Promise<IsSupportedResult>
Since: 0.0.1
enableTorch() => Promise<void>
Enable camera's torch (flash) during a scan session.
Only available on Android and iOS.
Since: 0.0.1
disableTorch() => Promise<void>
Disable camera's torch (flash) during a scan session.
Only available on Android and iOS.
Since: 0.0.1
toggleTorch() => Promise<void>
Toggle camera's torch (flash) during a scan session.
Only available on Android and iOS.
Since: 0.0.1
isTorchEnabled() => Promise<IsTorchEnabledResult>
Returns whether or not the camera's torch (flash) is enabled.
Only available on Android and iOS.
Returns: Promise<IsTorchEnabledResult>
Since: 0.0.1
isTorchAvailable() => Promise<IsTorchAvailableResult>
Returns whether or not the camera's torch (flash) is available.
Only available on Android and iOS.
Returns: Promise<IsTorchAvailableResult>
Since: 0.0.1
setZoomRatio(options: SetZoomRatioOptions) => Promise<void>
Set the zoom ratio of the camera.
Only available on Android and iOS.
Param | Type |
---|---|
options |
SetZoomRatioOptions |
Since: 5.4.0
getZoomRatio() => Promise<GetZoomRatioResult>
Get the zoom ratio of the camera.
Only available on Android and iOS.
Returns: Promise<GetZoomRatioResult>
Since: 5.4.0
getMinZoomRatio() => Promise<GetMinZoomRatioResult>
Get the minimum zoom ratio of the camera.
Only available on Android and iOS.
Returns: Promise<GetMinZoomRatioResult>
Since: 5.4.0
getMaxZoomRatio() => Promise<GetMaxZoomRatioResult>
Get the maximum zoom ratio of the camera.
Only available on Android and iOS.
Returns: Promise<GetMaxZoomRatioResult>
Since: 5.4.0
openSettings() => Promise<void>
Open the settings of the app so that the user can grant the camera permission.
Only available on Android and iOS.
Since: 0.0.1
isGoogleBarcodeScannerModuleAvailable() => Promise<IsGoogleBarcodeScannerModuleAvailableResult>
Check if the Google Barcode Scanner module is available.
If the Google Barcode Scanner module is not available, you can install it by using installGoogleBarcodeScannerModule()
.
Only available on Android.
Returns: Promise<IsGoogleBarcodeScannerModuleAvailableResult>
Since: 5.1.0
installGoogleBarcodeScannerModule() => Promise<void>
Install the Google Barcode Scanner module.
Attention: This only starts the installation.
The googleBarcodeScannerModuleInstallProgress
event listener will
notify you when the installation is complete.
Only available on Android.
Since: 5.1.0
checkPermissions() => Promise<PermissionStatus>
Check camera permission.
Only available on Android and iOS.
Returns: Promise<PermissionStatus>
Since: 0.0.1
requestPermissions() => Promise<PermissionStatus>
Request camera permission.
Only available on Android and iOS.
Returns: Promise<PermissionStatus>
Since: 0.0.1
addListener(eventName: 'barcodeScanned', listenerFunc: (event: BarcodeScannedEvent) => void) => Promise<PluginListenerHandle>
Called when a barcode is scanned.
Available on Android and iOS.
Param | Type |
---|---|
eventName |
'barcodeScanned' |
listenerFunc |
(event: BarcodeScannedEvent) => void |
Returns: Promise<PluginListenerHandle>
Since: 0.0.1
addListener(eventName: 'scanError', listenerFunc: (event: ScanErrorEvent) => void) => Promise<PluginListenerHandle>
Called when an error occurs during the scan.
Available on Android and iOS.
Param | Type |
---|---|
eventName |
'scanError' |
listenerFunc |
(event: ScanErrorEvent) => void |
Returns: Promise<PluginListenerHandle>
Since: 0.0.1
addListener(eventName: 'googleBarcodeScannerModuleInstallProgress', listenerFunc: (event: GoogleBarcodeScannerModuleInstallProgressEvent) => void) => Promise<PluginListenerHandle>
Called when the Google Barcode Scanner module is installed.
Available on Android.
Param | Type |
---|---|
eventName |
'googleBarcodeScannerModuleInstallProgress' |
listenerFunc |
(event: GoogleBarcodeScannerModuleInstallProgressEvent) => void |
Returns: Promise<PluginListenerHandle>
Since: 5.1.0
removeAllListeners() => Promise<void>
Remove all listeners for this plugin.
Since: 0.0.1
Prop | Type | Description | Since |
---|---|---|---|
formats |
BarcodeFormat[] |
Improve the speed of the barcode scanner by configuring the barcode formats to scan for. | 0.0.1 |
lensFacing |
LensFacing |
Configure the camera (front or back) to use. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
barcodes |
Barcode[] |
The detected barcodes. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
bytes |
number[] |
Raw bytes as it was encoded in the barcode. | 0.0.1 |
cornerPoints |
[[number, number], [number, number], [number, number], [number, number]] |
The four corner points of the barcode in clockwise order starting with top-left. This property is currently only supported by the startScan(...) method. |
0.0.1 |
displayValue |
string |
The barcode value in a human readable format. | 0.0.1 |
format |
BarcodeFormat |
The barcode format. | 0.0.1 |
rawValue |
string |
The barcode value in a machine readable format. | 0.0.1 |
valueType |
BarcodeValueType |
The barcode value type. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
formats |
BarcodeFormat[] |
Improve the speed of the barcode scanner by configuring the barcode formats to scan for. | 0.0.1 |
path |
string |
The local path to the image file. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
barcodes |
Barcode[] |
The detected barcodes. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
formats |
BarcodeFormat[] |
Improve the speed of the barcode scanner by configuring the barcode formats to scan for. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
supported |
boolean |
Whether or not the barcode scanner is supported by checking if the device has a camera. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
enabled |
boolean |
Whether or not the torch is enabled. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
available |
boolean |
Whether or not the torch is available. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
zoomRatio |
number |
The zoom ratio to set. | 5.4.0 |
Prop | Type | Description | Since |
---|---|---|---|
zoomRatio |
number |
The zoom ratio. | 5.4.0 |
Prop | Type | Description | Since |
---|---|---|---|
zoomRatio |
number |
The minimum zoom ratio. | 5.4.0 |
Prop | Type | Description | Since |
---|---|---|---|
zoomRatio |
number |
The maximum zoom ratio. | 5.4.0 |
Prop | Type | Description | Since |
---|---|---|---|
available |
boolean |
Whether or not the Google Barcode Scanner module is available. | 5.1.0 |
Prop | Type | Since |
---|---|---|
camera |
CameraPermissionState |
0.0.1 |
Prop | Type |
---|---|
remove |
() => Promise<void> |
Prop | Type | Description | Since |
---|---|---|---|
barcode |
Barcode |
A detected barcode. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
message |
string |
The error message. | 0.0.1 |
Prop | Type | Description | Since |
---|---|---|---|
state |
GoogleBarcodeScannerModuleInstallState |
The current state of the installation. | 5.1.0 |
progress |
number |
The progress of the installation in percent between 0 and 100. | 5.1.0 |
PermissionState | 'limited'
'prompt' | 'prompt-with-rationale' | 'granted' | 'denied'
Members | Value | Description | Since |
---|---|---|---|
Aztec |
'AZTEC' |
Only available on Android and iOS. | 0.0.1 |
Codabar |
'CODABAR' |
Only available on Android and iOS. | 0.0.1 |
Code39 |
'CODE_39' |
Only available on Android and iOS. | 0.0.1 |
Code93 |
'CODE_93' |
Only available on Android and iOS. | 0.0.1 |
Code128 |
'CODE_128' |
Only available on Android and iOS. | 0.0.1 |
DataMatrix |
'DATA_MATRIX' |
Only available on Android and iOS. | 0.0.1 |
Ean8 |
'EAN_8' |
Only available on Android and iOS. | 0.0.1 |
Ean13 |
'EAN_13' |
Only available on Android and iOS. | 0.0.1 |
Itf |
'ITF' |
Only available on Android and iOS. | 0.0.1 |
Pdf417 |
'PDF_417' |
Only available on Android and iOS. | 0.0.1 |
QrCode |
'QR_CODE' |
Only available on Android and iOS. | 0.0.1 |
UpcA |
'UPC_A' |
Only available on Android and iOS. | 0.0.1 |
UpcE |
'UPC_E' |
Only available on Android and iOS. | 0.0.1 |
Members | Value | Since |
---|---|---|
Front |
'FRONT' |
0.0.1 |
Back |
'BACK' |
0.0.1 |
Members | Value | Since |
---|---|---|
CalendarEvent |
'CALENDAR_EVENT' |
0.0.1 |
ContactInfo |
'CONTACT_INFO' |
0.0.1 |
DriversLicense |
'DRIVERS_LICENSE' |
0.0.1 |
Email |
'EMAIL' |
0.0.1 |
Geo |
'GEO' |
0.0.1 |
Isbn |
'ISBN' |
0.0.1 |
Phone |
'PHONE' |
0.0.1 |
Product |
'PRODUCT' |
0.0.1 |
Sms |
'SMS' |
0.0.1 |
Text |
'TEXT' |
0.0.1 |
Url |
'URL' |
0.0.1 |
Wifi |
'WIFI' |
0.0.1 |
Unknown |
'UNKNOWN' |
0.0.1 |
Members | Value | Since |
---|---|---|
UNKNOWN |
0 |
5.1.0 |
PENDING |
1 |
5.1.0 |
DOWNLOADING |
2 |
5.1.0 |
CANCELED |
3 |
5.1.0 |
COMPLETED |
4 |
5.1.0 |
FAILED |
5 |
5.1.0 |
INSTALLING |
6 |
5.1.0 |
DOWNLOAD_PAUSED |
7 |
5.1.0 |
The following error may occur when calling the startScan(...)
method: Attempt to invoke virtual method 'void androidx.camera.view.PreviewView.setScaleType(androidx.camera.view.PreviewView$ScaleType)' on a null object reference
.
In this case, make sure that the databinding library is enabled (see Data Binding).
This plugin uses the Google ML Kit:
See CHANGELOG.md.
See LICENSE.