Users can generate QR codes with their name & email using native Android code that automatically clears on logout/new login for security.

android/app/build.gradle

@@ -72,6 +72,11 @@ def enableProguardInReleaseBuilds = false
  */
 def jscFlavor = 'io.github.react-native-community:jsc-android:2026004.+'
 
+repositories {
+    google()
+    mavenCentral()
+}
+
 android {
     ndkVersion rootProject.ext.ndkVersion
     buildToolsVersion rootProject.ext.buildToolsVersion
@@ -116,4 +121,7 @@ dependencies {
     } else {
         implementation jscFlavor
     }
+
+    // QR Code generation
+    implementation 'com.google.zxing:core:3.5.1'
 }

android/app/src/main/java/com/lynkeduppro/MyNativeModule.kt

@@ -4,6 +4,12 @@ import com.facebook.react.bridge.ReactApplicationContext
 import com.facebook.react.bridge.ReactContextBaseJavaModule
 import com.facebook.react.bridge.ReactMethod
 import com.facebook.react.bridge.Promise
+import android.graphics.Bitmap
+import android.graphics.Color
+import android.util.Base64
+import java.io.ByteArrayOutputStream
+import java.nio.charset.StandardCharsets
+import java.security.MessageDigest
 
 class MyNativeModule(private val reactContext: ReactApplicationContext)
     : ReactContextBaseJavaModule(reactContext) {
@@ -16,4 +22,36 @@ class MyNativeModule(private val reactContext: ReactApplicationContext)
     fun greet(name: String, promise: Promise) {
         promise.resolve("Hello $name from Android(Kotlin)!")
     }
+
+    @ReactMethod
+    fun generateQRCode(data: String, width: Int, height: Int, promise: Promise) {
+        try {
+            val bitmap = createQRCodeBitmap(data, width, height)
+            val base64Image = bitmapToBase64(bitmap)
+            promise.resolve(base64Image)
+        } catch (e: Exception) {
+            promise.reject("QR_CODE_ERROR", "Failed to generate QR code: ${e.message}")
+        }
+    }
+
+    private fun createQRCodeBitmap(data: String, width: Int, height: Int): Bitmap {
+        // Use ZXing library for QR code generation
+        val qrCodeWriter = com.google.zxing.qrcode.QRCodeWriter()
+        val bitMatrix = qrCodeWriter.encode(data, com.google.zxing.BarcodeFormat.QR_CODE, width, height)
+        
+        val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565)
+        for (y in 0 until height) {
+            for (x in 0 until width) {
+                bitmap.setPixel(x, y, if (bitMatrix[x, y]) Color.BLACK else Color.WHITE)
+            }
+        }
+        return bitmap
+    }
+
+    private fun bitmapToBase64(bitmap: Bitmap): String {
+        val outputStream = ByteArrayOutputStream()
+        bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream)
+        val byteArray = outputStream.toByteArray()
+        return "data:image/png;base64," + Base64.encodeToString(byteArray, Base64.DEFAULT)
+    }
 }