mirror of
https://github.com/tauri-apps/plugins-workspace.git
synced 2026-04-23 11:36:13 +02:00
feat: add barcode scanner plugin (#536)
This commit is contained in:
Lucas Fernandes Nogueira
committed by
GitHub
GitHub
parent
eccd6f977a
commit
454428cd50
@@ -0,0 +1,438 @@
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// Copyright 2019-2023 Tauri Programme within The Commons Conservancy
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// SPDX-License-Identifier: Apache-2.0
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// SPDX-License-Identifier: MIT
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package app.tauri.barcodescanner
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import android.Manifest
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import android.annotation.SuppressLint
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import android.app.Activity
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import android.content.Context
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import android.content.Context.MODE_PRIVATE
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import android.content.Intent
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import android.content.SharedPreferences
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import android.content.pm.PackageManager
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import android.graphics.Color
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import android.graphics.drawable.Drawable
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import android.net.Uri
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import android.os.Build
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import android.os.VibrationEffect
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import android.os.Vibrator
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import android.provider.Settings
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import android.util.Size
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import android.view.ViewGroup
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import android.webkit.WebView
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import android.widget.FrameLayout
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import androidx.activity.result.ActivityResult
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import androidx.camera.core.Camera
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import androidx.camera.core.CameraSelector
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import androidx.camera.core.ImageAnalysis
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import androidx.camera.core.ImageProxy
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import androidx.camera.core.Preview
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import androidx.camera.lifecycle.ProcessCameraProvider
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import androidx.camera.view.PreviewView
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import androidx.core.content.ContextCompat
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import androidx.lifecycle.LifecycleOwner
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import app.tauri.Logger
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import app.tauri.PermissionState
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import app.tauri.annotation.ActivityCallback
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import app.tauri.annotation.Command
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import app.tauri.annotation.Permission
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import app.tauri.annotation.PermissionCallback
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import app.tauri.annotation.TauriPlugin
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import app.tauri.plugin.Invoke
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import app.tauri.plugin.JSArray
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import app.tauri.plugin.JSObject
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import app.tauri.plugin.Plugin
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import com.google.common.util.concurrent.ListenableFuture
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import com.google.mlkit.vision.barcode.BarcodeScannerOptions
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import com.google.mlkit.vision.barcode.BarcodeScanning
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import com.google.mlkit.vision.barcode.common.Barcode
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import com.google.mlkit.vision.common.InputImage
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import org.json.JSONException
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import java.util.Collections
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import java.util.concurrent.ExecutionException
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private const val PERMISSION_ALIAS_CAMERA = "camera"
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private const val PERMISSION_NAME = Manifest.permission.CAMERA
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private const val PREFS_PERMISSION_FIRST_TIME_ASKING = "PREFS_PERMISSION_FIRST_TIME_ASKING"
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@TauriPlugin(
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permissions = [
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Permission(strings = [Manifest.permission.CAMERA], alias = "camera")
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]
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)
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class BarcodeScannerPlugin(private val activity: Activity) : Plugin(activity),
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ImageAnalysis.Analyzer {
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private lateinit var webView: WebView
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private var previewView: PreviewView? = null
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private var cameraProviderFuture: ListenableFuture<ProcessCameraProvider>? = null
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private var cameraProvider: ProcessCameraProvider? = null
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private var graphicOverlay: GraphicOverlay? = null
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private var camera: Camera? = null
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private var vibrator: Vibrator? = null
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private var scannerOptions: BarcodeScannerOptions? = null
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private var scanner: com.google.mlkit.vision.barcode.BarcodeScanner? = null
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private var requestPermissionResponse: JSObject? = null
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private var windowed = false
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// declare a map constant for allowed barcode formats
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private val supportedFormats = supportedFormats()
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private var savedInvoke: Invoke? = null
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private var webViewBackground: Drawable? = null
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override fun load(webView: WebView) {
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super.load(webView)
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this.webView = webView
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}
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private fun supportedFormats(): Map<String, Int> {
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val map: MutableMap<String, Int> = HashMap()
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map["UPC_A"] = Barcode.FORMAT_UPC_A
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map["UPC_E"] = Barcode.FORMAT_UPC_E
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map["EAN_8"] = Barcode.FORMAT_EAN_8
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map["EAN_13"] = Barcode.FORMAT_EAN_13
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map["CODE_39"] = Barcode.FORMAT_CODE_39
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map["CODE_93"] = Barcode.FORMAT_CODE_93
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map["CODE_128"] = Barcode.FORMAT_CODE_128
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map["CODABAR"] = Barcode.FORMAT_CODABAR
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map["ITF"] = Barcode.FORMAT_ITF
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map["AZTEC"] = Barcode.FORMAT_AZTEC
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map["DATA_MATRIX"] = Barcode.FORMAT_DATA_MATRIX
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map["PDF_417"] = Barcode.FORMAT_PDF417
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map["QR_CODE"] = Barcode.FORMAT_QR_CODE
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return Collections.unmodifiableMap(map)
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}
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private fun hasCamera(): Boolean {
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return activity.packageManager
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.hasSystemFeature(PackageManager.FEATURE_CAMERA_ANY)
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}
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private fun setupCamera(cameraDirection: String, windowed: Boolean) {
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activity
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.runOnUiThread {
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val previewView = PreviewView(activity)
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previewView.layoutParams = FrameLayout.LayoutParams(
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ViewGroup.LayoutParams.MATCH_PARENT,
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ViewGroup.LayoutParams.MATCH_PARENT
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)
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this.previewView = previewView
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val graphicOverlay = GraphicOverlay(activity)
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graphicOverlay.layoutParams = FrameLayout.LayoutParams(
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ViewGroup.LayoutParams.MATCH_PARENT,
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ViewGroup.LayoutParams.MATCH_PARENT
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)
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this.graphicOverlay = graphicOverlay
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val parent = webView.parent as ViewGroup
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parent.addView(previewView)
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parent.addView(graphicOverlay)
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this.windowed = windowed
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if (windowed) {
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webView.bringToFront()
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webViewBackground = webView.background
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webView.setBackgroundColor(Color.TRANSPARENT)
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}
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val cameraProviderFuture = ProcessCameraProvider.getInstance(activity)
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cameraProviderFuture.addListener(
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{
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try {
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val cameraProvider = cameraProviderFuture.get()
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bindPreview(
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cameraProvider,
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if (cameraDirection == "front") CameraSelector.LENS_FACING_FRONT else CameraSelector.LENS_FACING_BACK
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)
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this.cameraProvider = cameraProvider
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} catch (e: InterruptedException) {
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// ignored
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} catch (_: ExecutionException) {
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// ignored
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}
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},
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ContextCompat.getMainExecutor(activity)
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)
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this.cameraProviderFuture = cameraProviderFuture
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}
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}
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private fun bindPreview(cameraProvider: ProcessCameraProvider, cameraDirection: Int) {
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activity
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.runOnUiThread {
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val preview = Preview.Builder().build()
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val cameraSelector =
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CameraSelector.Builder().requireLensFacing(cameraDirection).build()
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preview.setSurfaceProvider(previewView?.surfaceProvider)
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val imageAnalysis = ImageAnalysis.Builder()
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.setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST)
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.setTargetResolution(Size(1280, 720))
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.build()
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imageAnalysis.setAnalyzer(
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ContextCompat.getMainExecutor(activity),
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this
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)
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try {
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camera = cameraProvider.bindToLifecycle(
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activity as LifecycleOwner,
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cameraSelector,
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preview,
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imageAnalysis
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)
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} catch (e: Exception) {
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// TODO
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}
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}
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}
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private fun dismantleCamera() {
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activity
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.runOnUiThread {
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if (cameraProvider != null) {
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cameraProvider?.unbindAll()
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val parent = webView.parent as ViewGroup
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parent.removeView(previewView)
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parent.removeView(graphicOverlay)
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camera = null
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previewView = null
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graphicOverlay = null
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}
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}
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}
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private fun getFormats(invoke: Invoke): List<Int> {
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val jsFormats = invoke.getArray("formats", JSArray())
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val formats = ArrayList<Int>()
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for (i in 0 until jsFormats.length()) {
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try {
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val targetedFormat: String = jsFormats.getString(i)
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val targetedBarcodeFormat =
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supportedFormats[targetedFormat]
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if (targetedBarcodeFormat != null) {
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formats.add(targetedBarcodeFormat)
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}
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} catch (e: JSONException) {
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e.printStackTrace()
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}
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}
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return formats
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}
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private fun prepare(direction: String, windowed: Boolean) {
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dismantleCamera()
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setupCamera(direction, windowed)
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}
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private fun destroy() {
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dismantleCamera()
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savedInvoke = null
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if (windowed) {
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if (webViewBackground != null) {
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webView.background = webViewBackground
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webViewBackground = null
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} else {
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webView.setBackgroundColor(Color.WHITE)
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}
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}
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}
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@Suppress("DEPRECATION")
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private fun configureCamera(formats: List<Int>) {
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activity
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.runOnUiThread {
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val vibrator =
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activity.getSystemService(Context.VIBRATOR_SERVICE) as Vibrator
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this.vibrator = vibrator
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if (previewView == null) {
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throw Exception("Something went wrong configuring the BarcodeScanner")
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}
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if (formats.isNotEmpty()) {
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val mappedFormats = mapFormats(formats)
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val options =
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BarcodeScannerOptions.Builder()
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.setBarcodeFormats(Barcode.FORMAT_QR_CODE, *mappedFormats).build()
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scannerOptions = options
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scanner = BarcodeScanning.getClient(options)
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} else {
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val options = BarcodeScannerOptions.Builder()
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.setBarcodeFormats(Barcode.FORMAT_ALL_FORMATS).build()
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scannerOptions = options
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scanner = BarcodeScanning.getClient(options)
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}
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}
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}
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private fun mapFormats(integers: List<Int>): IntArray {
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val ret = IntArray(integers.size)
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for (i in ret.indices) {
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if (integers[i] != Barcode.FORMAT_QR_CODE) ret[i] = integers[i]
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}
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return ret
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}
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override fun analyze(image: ImageProxy) {
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@SuppressLint("UnsafeOptInUsageError") val mediaImage = image.image
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if (mediaImage != null) {
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val inputImage =
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InputImage.fromMediaImage(mediaImage, image.imageInfo.rotationDegrees)
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scanner
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?.process(inputImage)
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?.addOnSuccessListener { barcodes ->
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if (barcodes.isNotEmpty()) {
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val barcode = barcodes[0]
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val bounds = barcode.boundingBox
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val rawValue = barcode.rawValue ?: ""
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val rawFormat = barcode.format
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var format: String? = null
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for (entry in supportedFormats.entries) {
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if (entry.value == rawFormat) {
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format = entry.key
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break
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}
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}
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val s = bounds?.flattenToString()
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val jsObject = JSObject()
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jsObject.put("content", rawValue)
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jsObject.put("format", format)
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jsObject.put("bounds", s)
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savedInvoke?.resolve(jsObject)
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destroy()
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}
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}
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?.addOnFailureListener { e ->
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Logger.error(e.message ?: e.toString())
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}
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?.addOnCompleteListener {
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image.close()
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mediaImage.close()
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}
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}
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}
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@Command
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fun vibrate(invoke: Invoke) {
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if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
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vibrator!!.vibrate(
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VibrationEffect.createOneShot(
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50,
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VibrationEffect.DEFAULT_AMPLITUDE
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)
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)
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}
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invoke.resolve()
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}
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@Command
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fun cancel(invoke: Invoke) {
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destroy()
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savedInvoke?.reject("cancelled")
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invoke.resolve()
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}
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@Command
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fun scan(invoke: Invoke) {
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savedInvoke = invoke
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if (hasCamera()) {
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if (getPermissionState("camera") != PermissionState.GRANTED) {
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throw Exception("No permission to use camera. Did you request it yet?")
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} else {
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webViewBackground = null
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prepare(invoke.getString("cameraDirection", "back"), invoke.getBoolean("windowed", false))
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configureCamera(getFormats(invoke))
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}
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}
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}
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private fun markFirstPermissionRequest() {
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val sharedPreference: SharedPreferences =
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activity.getSharedPreferences(PREFS_PERMISSION_FIRST_TIME_ASKING, MODE_PRIVATE)
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sharedPreference.edit().putBoolean(PERMISSION_NAME, false).apply()
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}
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private fun firstPermissionRequest(): Boolean {
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return activity.getSharedPreferences(PREFS_PERMISSION_FIRST_TIME_ASKING, MODE_PRIVATE)
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.getBoolean(PERMISSION_NAME, true)
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}
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@SuppressLint("ObsoleteSdkInt")
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@PermissionCallback
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fun cameraPermissionCallback(invoke: Invoke) {
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if (requestPermissionResponse == null) {
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return
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}
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val requestPermissionResponse = requestPermissionResponse!!
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val granted = getPermissionState(PERMISSION_ALIAS_CAMERA) === PermissionState.GRANTED
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if (granted) {
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requestPermissionResponse.put(PERMISSION_ALIAS_CAMERA, PermissionState.GRANTED)
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} else {
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if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
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if (!activity.shouldShowRequestPermissionRationale(PERMISSION_NAME)) {
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requestPermissionResponse.put(PERMISSION_ALIAS_CAMERA, PermissionState.DENIED)
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}
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} else {
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requestPermissionResponse.put(PERMISSION_ALIAS_CAMERA, PermissionState.GRANTED)
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}
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}
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invoke.resolve(requestPermissionResponse)
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this.requestPermissionResponse = null
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}
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@SuppressLint("ObsoleteSdkInt")
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@Command
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override fun requestPermissions(invoke: Invoke) {
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val requestPermissionResponse = JSObject()
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this.requestPermissionResponse = requestPermissionResponse
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if (getPermissionState(PERMISSION_ALIAS_CAMERA) === PermissionState.GRANTED) {
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requestPermissionResponse.put(PERMISSION_ALIAS_CAMERA, PermissionState.GRANTED)
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} else {
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if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
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if (firstPermissionRequest() || activity.shouldShowRequestPermissionRationale(
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PERMISSION_NAME
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)
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) {
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markFirstPermissionRequest()
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requestPermissionForAlias(
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PERMISSION_ALIAS_CAMERA,
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invoke,
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"cameraPermissionCallback"
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)
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return
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} else {
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requestPermissionResponse.put(PERMISSION_ALIAS_CAMERA, PermissionState.DENIED)
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}
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} else {
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requestPermissionResponse.put(PERMISSION_ALIAS_CAMERA, PermissionState.GRANTED)
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}
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}
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invoke.resolve(requestPermissionResponse)
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}
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@Command
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fun openAppSettings(invoke: Invoke) {
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val intent = Intent(
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Settings.ACTION_APPLICATION_DETAILS_SETTINGS,
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Uri.fromParts("package", activity.packageName, null)
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)
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intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
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startActivityForResult(invoke, intent, "openSettingsResult")
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}
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@ActivityCallback
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private fun openSettingsResult(invoke: Invoke, result: ActivityResult) {
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invoke.resolve()
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}
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}
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@@ -0,0 +1,192 @@
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// Copyright 2019-2023 Tauri Programme within The Commons Conservancy
|
||||
// SPDX-License-Identifier: Apache-2.0
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// SPDX-License-Identifier: MIT
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package app.tauri.barcodescanner
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import android.content.Context
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import android.graphics.Canvas
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import android.graphics.Matrix
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import android.graphics.Paint
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import android.util.AttributeSet
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import android.view.View
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import com.google.android.gms.common.internal.Preconditions
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class GraphicOverlay: View {
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private val lock = Any()
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private val graphics: MutableList<Graphic> = ArrayList()
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private val transformationMatrix = Matrix()
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private var imageWidth = 0
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private var imageHeight = 0
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private var scaleFactor = 1.0f
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private var postScaleWidthOffset = 0f
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private var postScaleHeightOffset = 0f
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private var isImageFlipped = false
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private var needUpdateTransformation = true
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abstract class Graphic(private val overlay: GraphicOverlay) {
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abstract fun draw(canvas: Canvas?)
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protected fun drawRect(
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canvas: Canvas,
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left: Float,
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top: Float,
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right: Float,
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bottom: Float,
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paint: Paint?
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) {
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canvas.drawRect(left, top, right, bottom, paint!!)
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}
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protected fun drawText(canvas: Canvas, text: String?, x: Float, y: Float, paint: Paint?) {
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canvas.drawText(text!!, x, y, paint!!)
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}
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/** Adjusts the supplied value from the image scale to the view scale. */
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fun scale(imagePixel: Float): Float {
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return imagePixel * overlay.scaleFactor
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}
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val applicationContext
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get() = overlay.context.applicationContext
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fun isImageFlipped(): Boolean {
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return overlay.isImageFlipped
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}
|
||||
|
||||
fun translateX(x: Float): Float {
|
||||
return if (overlay.isImageFlipped) {
|
||||
overlay.width - (scale(x) - overlay.postScaleWidthOffset)
|
||||
} else {
|
||||
scale(x) - overlay.postScaleWidthOffset
|
||||
}
|
||||
}
|
||||
|
||||
fun translateY(y: Float): Float {
|
||||
return scale(y) - overlay.postScaleHeightOffset
|
||||
}
|
||||
|
||||
fun getTransformationMatrix(): Matrix {
|
||||
return overlay.transformationMatrix
|
||||
}
|
||||
|
||||
fun postInvalidate() {
|
||||
overlay.postInvalidate()
|
||||
}
|
||||
|
||||
fun updatePaintColorByZValue(
|
||||
paint: Paint,
|
||||
canvas: Canvas,
|
||||
visualizeZ: Boolean,
|
||||
rescaleZForVisualization: Boolean,
|
||||
zInImagePixel: Float,
|
||||
zMin: Float,
|
||||
zMax: Float
|
||||
) {
|
||||
if (!visualizeZ) {
|
||||
return
|
||||
}
|
||||
|
||||
val zLowerBoundInScreenPixel: Float
|
||||
val zUpperBoundInScreenPixel: Float
|
||||
if (rescaleZForVisualization) {
|
||||
zLowerBoundInScreenPixel = (-0.001f).coerceAtMost(scale(zMin))
|
||||
zUpperBoundInScreenPixel = 0.001f.coerceAtLeast(scale(zMax))
|
||||
} else {
|
||||
val defaultRangeFactor = 1f
|
||||
zLowerBoundInScreenPixel = -defaultRangeFactor * canvas.width
|
||||
zUpperBoundInScreenPixel = defaultRangeFactor * canvas.width
|
||||
}
|
||||
val zInScreenPixel = scale(zInImagePixel)
|
||||
if (zInScreenPixel < 0) {
|
||||
val v = (zInScreenPixel / zLowerBoundInScreenPixel * 255).toInt()
|
||||
paint.setARGB(0, 0, 255, 0)
|
||||
} else {
|
||||
val v = (zInScreenPixel / zUpperBoundInScreenPixel * 255).toInt()
|
||||
paint.setARGB(0, 0, 255, 0)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
constructor(context: Context): super(context)
|
||||
|
||||
constructor(context: Context, attrs: AttributeSet): super(context, attrs) {
|
||||
addOnLayoutChangeListener { _, _, _, _, _, _, _, _, _ ->
|
||||
needUpdateTransformation = true
|
||||
}
|
||||
}
|
||||
|
||||
fun clear() {
|
||||
synchronized(lock) { graphics.clear() }
|
||||
postInvalidate()
|
||||
}
|
||||
|
||||
fun add(graphic: Graphic) {
|
||||
synchronized(lock) { graphics.add(graphic) }
|
||||
}
|
||||
|
||||
fun remove(graphic: Graphic) {
|
||||
synchronized(lock) { graphics.remove(graphic) }
|
||||
postInvalidate()
|
||||
}
|
||||
|
||||
fun setImageSourceInfo(imageWidth: Int, imageHeight: Int, isFlipped: Boolean) {
|
||||
Preconditions.checkState(imageWidth > 0, "image width must be positive")
|
||||
Preconditions.checkState(imageHeight > 0, "image height must be positive")
|
||||
synchronized(lock) {
|
||||
this.imageWidth = imageWidth
|
||||
this.imageHeight = imageHeight
|
||||
isImageFlipped = isFlipped
|
||||
needUpdateTransformation = true
|
||||
}
|
||||
postInvalidate()
|
||||
}
|
||||
|
||||
fun getImageWidth(): Int {
|
||||
return imageWidth
|
||||
}
|
||||
|
||||
fun getImageHeight(): Int {
|
||||
return imageHeight
|
||||
}
|
||||
|
||||
private fun updateTransformationIfNeeded() {
|
||||
if (!needUpdateTransformation || imageWidth <= 0 || imageHeight <= 0) {
|
||||
return
|
||||
}
|
||||
val viewAspectRatio = width.toFloat() / height
|
||||
val imageAspectRatio = imageWidth.toFloat() / imageHeight
|
||||
postScaleWidthOffset = 0f
|
||||
postScaleHeightOffset = 0f
|
||||
if (viewAspectRatio > imageAspectRatio) {
|
||||
// The image needs to be vertically cropped to be displayed in this view.
|
||||
scaleFactor = width.toFloat() / imageWidth
|
||||
postScaleHeightOffset = (width.toFloat() / imageAspectRatio - height) / 2
|
||||
} else {
|
||||
// The image needs to be horizontally cropped to be displayed in this view.
|
||||
scaleFactor = height.toFloat() / imageHeight
|
||||
postScaleWidthOffset = (height.toFloat() * imageAspectRatio - width) / 2
|
||||
}
|
||||
transformationMatrix.reset()
|
||||
transformationMatrix.setScale(scaleFactor, scaleFactor)
|
||||
transformationMatrix.postTranslate(-postScaleWidthOffset, -postScaleHeightOffset)
|
||||
if (isImageFlipped) {
|
||||
transformationMatrix.postScale(-1f, 1f, width / 2f, height / 2f)
|
||||
}
|
||||
needUpdateTransformation = false
|
||||
}
|
||||
|
||||
override fun onDraw(canvas: Canvas?) {
|
||||
super.onDraw(canvas)
|
||||
synchronized(lock) {
|
||||
updateTransformationIfNeeded()
|
||||
for (graphic in graphics) {
|
||||
graphic.draw(canvas)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user