Link new device using QrCode.

libraries/qrcode/build.gradle.kts

@@ -19,4 +19,5 @@ dependencies {
     implementation(libs.androidx.camera.view)
     implementation(libs.androidx.camera.camera2)
     implementation(libs.zxing.cpp)
+    implementation(libs.google.zxing)
 }

libraries/qrcode/src/main/kotlin/io/element/android/libraries/qrcode/QrCodeCameraView.kt

@@ -31,6 +31,7 @@ import androidx.compose.ui.draw.clipToBounds
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalInspectionMode
+import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.viewinterop.AndroidView
 import androidx.core.content.ContextCompat
 import androidx.lifecycle.compose.LocalLifecycleOwner
@@ -117,7 +118,13 @@ fun QrCodeCameraView(
                     .background(color = ElementTheme.colors.bgSubtlePrimary),
                 contentAlignment = Alignment.Center,
             ) {
-                Text("CameraView")
+                Text(
+                    text = buildString {
+                        append("CameraView\n")
+                        append(if (isScanning) "scanning" else "frozen")
+                    },
+                    textAlign = TextAlign.Center,
+                )
             }
         } else {
             AndroidView(

libraries/qrcode/src/main/kotlin/io/element/android/libraries/qrcode/QrCodeImage.kt

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.qrcode
+
+import android.graphics.Bitmap
+import android.graphics.Color
+import androidx.annotation.ColorInt
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxHeight
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.asImageBitmap
+import androidx.compose.ui.layout.onSizeChanged
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.IntSize
+import com.google.zxing.BarcodeFormat
+import com.google.zxing.common.BitMatrix
+import com.google.zxing.qrcode.QRCodeWriter
+import io.element.android.libraries.designsystem.modifiers.squareSize
+import io.element.android.libraries.designsystem.utils.ForceMaxBrightness
+
+private fun String.toBitMatrix(size: Int): BitMatrix {
+    return QRCodeWriter().encode(
+        this,
+        BarcodeFormat.QR_CODE,
+        size,
+        size,
+    )
+}
+
+private fun BitMatrix.toBitmap(
+    @ColorInt backgroundColor: Int = Color.WHITE,
+    @ColorInt foregroundColor: Int = Color.BLACK,
+): Bitmap {
+    val colorBuffer = IntArray(width * height)
+    var rowOffset = 0
+    for (y in 0 until height) {
+        for (x in 0 until width) {
+            val arrayIndex = x + rowOffset
+            colorBuffer[arrayIndex] = if (get(x, y)) foregroundColor else backgroundColor
+        }
+        rowOffset += width
+    }
+    return Bitmap.createBitmap(colorBuffer, width, height, Bitmap.Config.ARGB_8888)
+}
+
+@Composable
+fun QrCodeImage(
+    data: String,
+    forceMaxBrightness: Boolean = true,
+    modifier: Modifier = Modifier,
+) {
+    if (forceMaxBrightness) {
+        ForceMaxBrightness()
+    }
+    var size by remember { mutableStateOf(IntSize.Zero) }
+    Box(
+        modifier = modifier
+            .squareSize()
+            .onSizeChanged {
+                size = it
+            },
+    ) {
+        val image = remember(data, size) {
+            val sideSide = maxOf(size.width, size.height).coerceAtLeast(128)
+            data.toBitMatrix(sideSide).toBitmap().asImageBitmap()
+        }
+        Image(
+            contentDescription = null,
+            bitmap = image,
+        )
+    }
+}
+
+@Composable
+@Preview
+internal fun QrCodeViewPreview() {
+    QrCodeImage(
+        modifier = Modifier.fillMaxHeight(),
+        data = "RANDOM_QRCODE_DATA",
+    )
+}