QR Code scanning with camera

app/src/main/AndroidManifest.xml

@@ -50,11 +50,8 @@
 
     <!-- Uart access -->
 
-
-    <!-- the xing library will try to bring this permission in but we don't want it -->
-    <uses-permission
-        android:name="android.permission.CAMERA"
-        tools:node="remove" />
+    <!-- zxing library for QR Code scanning using camera -->
+    <uses-permission android:name="android.permission.CAMERA" />
 
     <uses-feature
         android:name="android.hardware.bluetooth_le"
@@ -117,6 +114,12 @@
             android:enabled="true"
             android:exported="false" />
 
+        <!-- zxing for QR Code scanning: lock portrait orientation -->
+        <activity
+            android:name="com.journeyapps.barcodescanner.CaptureActivity"
+            android:screenOrientation="portrait"
+            tools:replace="screenOrientation" />
+
         <activity
             android:name="com.geeksville.mesh.MainActivity"
             android:label="@string/app_name"

app/src/main/java/com/geeksville/mesh/ui/ChannelFragment.kt

@@ -4,6 +4,7 @@ import android.content.ActivityNotFoundException
 import android.content.Intent
 import android.graphics.ColorMatrix
 import android.graphics.ColorMatrixColorFilter
+import android.net.Uri
 import android.os.Bundle
 import android.os.RemoteException
 import android.view.LayoutInflater
@@ -29,6 +30,8 @@ import com.geeksville.mesh.service.MeshService
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import com.google.android.material.snackbar.Snackbar
 import com.google.protobuf.ByteString
+import com.google.zxing.integration.android.IntentIntegrator
+import java.net.MalformedURLException
 import java.security.SecureRandom
 
 
@@ -70,6 +73,7 @@ class ChannelFragment : ScreenFragment("Channel"), Logging {
 
         binding.channelOptions.isEnabled = isEditing
         binding.shareButton.isEnabled = !isEditing
+        binding.scanButton.isEnabled = isEditing
         binding.channelNameView.isEnabled = isEditing
         if (isEditing) // Dim the (stale) QR code while editing...
             binding.qrView.setDim()
@@ -203,6 +207,15 @@ class ChannelFragment : ScreenFragment("Channel"), Logging {
                 .show()
         }
 
+        binding.scanButton.setOnClickListener {
+            val zxingScan = IntentIntegrator.forSupportFragment(this)
+            zxingScan.setCameraId(0)
+            zxingScan.setPrompt("")
+            zxingScan.setBeepEnabled(false)
+            zxingScan.setDesiredBarcodeFormats(IntentIntegrator.QR_CODE)
+            zxingScan.initiateScan()
+        }
+
         // Note: Do not use setOnCheckedChanged here because we don't want to be called when we programmatically disable editing
         binding.editableCheckbox.setOnClickListener { _ ->
 
@@ -287,4 +300,25 @@ class ChannelFragment : ScreenFragment("Channel"), Logging {
 
         return ChannelProtos.ChannelSettings.ModemConfig.UNRECOGNIZED
     }
-}
+
+    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
+        val result = IntentIntegrator.parseActivityResult(requestCode, resultCode, data)
+        if (result != null) {
+            if (result.contents == null) {
+                Snackbar.make(binding.scanButton, R.string.channel_invalid, Snackbar.LENGTH_LONG).show()
+            } else {
+                try {
+                    val intent = Intent(Intent.ACTION_VIEW)
+                    intent.data = ChannelSet(Uri.parse(result.contents)).getChannelUrl(false)
+                    startActivity(intent)
+                } catch (ex: ActivityNotFoundException) {
+                    Snackbar.make(binding.scanButton, R.string.channel_invalid, Snackbar.LENGTH_LONG).show()
+                } catch (ex: MalformedURLException) {
+                    Snackbar.make(binding.scanButton, R.string.channel_invalid, Snackbar.LENGTH_LONG).show()
+                }
+            }
+        } else {
+            super.onActivityResult(requestCode, resultCode, data)
+        }
+    }
+}

app/src/main/res/layout/channel_fragment.xml

@@ -98,30 +98,40 @@
         android:id="@+id/resetButton"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginStart="32dp"
+        android:layout_marginEnd="10dp"
         android:text="@string/reset"
         app:icon="@drawable/ic_twotone_public_24"
         app:layout_constraintBottom_toBottomOf="@id/bottomButtonsGuideline"
-        app:layout_constraintStart_toStartOf="parent" />
+        app:layout_constraintEnd_toStartOf="@id/editableCheckbox" />
+
+    <Button
+        android:id="@+id/scanButton"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="10dp"
+        android:text="Scan"
+        app:layout_constraintBottom_toBottomOf="@id/bottomButtonsGuideline"
+        app:layout_constraintStart_toEndOf="@id/editableCheckbox" />
 
     <CheckBox
         android:id="@+id/editableCheckbox"
+        android:minWidth="0dp"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginStart="8dp"
         android:button="@drawable/sl_lock_24dp"
         app:layout_constraintBottom_toBottomOf="@id/bottomButtonsGuideline"
-        app:layout_constraintStart_toEndOf="@+id/resetButton"></CheckBox>
+        app:layout_constraintLeft_toLeftOf="parent"
+        app:layout_constraintRight_toRightOf="parent" />
 
     <ImageButton
         android:id="@+id/shareButton"
         style="@android:style/Widget.Material.ImageButton"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginEnd="32dp"
+        android:layout_marginEnd="16dp"
         android:contentDescription="@string/share"
         app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintTop_toTopOf="@+id/editableCheckbox"
+        app:layout_constraintBottom_toBottomOf="@id/bottomButtonsGuideline"
         app:srcCompat="@drawable/ic_twotone_share_24" />
 
     <androidx.constraintlayout.widget.Guideline