Added QR code scanning.

res/layout/activity_seed.xml

@@ -96,6 +96,17 @@
             app:labeledEditText_background="@color/loki_darkest_gray"
             app:labeledEditText_label="@string/activity_key_pair_public_key_edit_text_label"/>
 
+        <Button
+            android:id="@+id/scanQRButton"
+            android:layout_width="match_parent"
+            android:layout_height="50dp"
+            android:background="@color/transparent"
+            android:elevation="0dp"
+            android:stateListAnimator="@null"
+            android:text="@string/fragment_scan_qr_code_title"
+            android:textColor="@color/signal_primary"
+            android:visibility="gone" />
+
         <Button
             android:id="@+id/toggleRestoreModeButton"
             android:layout_width="match_parent"
@@ -123,7 +134,7 @@
             android:layout_height="50dp"
             android:background="@color/transparent"
             android:textColor="@color/signal_primary"
-            android:text="Link Device"
+            android:text="@string/activity_key_pair_toggle_mode_button_title_3"
             android:elevation="0dp"
             android:stateListAnimator="@null" />
 

res/layout/fragment_scan_qr_code.xml

@@ -24,13 +24,14 @@
             android:layout_height="match_parent"/>
 
         <TextView
+            android:id="@+id/descriptionTextView"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:layout_weight="1"
             android:padding="32dp"
             android:gravity="center"
             android:background="@color/loki_darkest_gray"
-            android:text="@string/fragment_scan_qr_code_explanation"
+            android:text="@string/fragment_scan_qr_code_explanation_new_conversation"
             android:textColor="?android:textColorPrimary" />
 
     </LinearLayout>

res/layout/view_device_linking.xml

@@ -16,6 +16,13 @@
         android:indeterminate="true"
         android:progressTint="@color/white" />
 
+    <ImageView
+        android:id="@+id/qrCodeImageView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:background="@color/white" />
+
     <TextView
         android:id="@+id/titleTextView"
         style="@style/Signal.Text.Headline"

res/values/strings.xml

@@ -1638,7 +1638,8 @@
     <string name="view_device_linking_cancel_button_title">Cancel</string>
     <!-- Scan QR code fragment -->
     <string name="fragment_scan_qr_code_title">Scan QR Code</string>
-    <string name="fragment_scan_qr_code_explanation">Scan the QR code of the person you\'d like to securely message. They can find their QR code by going into Loki Messenger\'s in-app settings and clicking \"Show QR Code\".</string>
+    <string name="fragment_scan_qr_code_explanation_new_conversation">Scan the QR code of the person you\'d like to securely message. They can find their QR code by going into Loki Messenger\'s in-app settings and clicking \"Show QR Code\".</string>
+    <string name="fragment_scan_qr_code_explanation_link_device">Scan the QR code of the device you would like to link.</string>
     <string name="fragment_scan_qr_code_camera_permission_dialog_message">Loki Messenger needs camera access to scan QR codes.</string>
     <!-- Conversation activity -->
     <string name="activity_conversation_copy_public_key_button_title">Copy public key</string>

src/org/thoughtcrime/securesms/loki/DeviceLinkingView.kt

@@ -4,13 +4,17 @@ import android.content.Context
 import android.graphics.Color
 import android.graphics.PorterDuff
 import android.os.Handler
-import android.text.Editable
-import android.text.TextWatcher
 import android.util.AttributeSet
+import android.util.DisplayMetrics
 import android.view.View
 import android.widget.LinearLayout
 import kotlinx.android.synthetic.main.view_device_linking.view.*
+import kotlinx.android.synthetic.main.view_device_linking.view.cancelButton
+import kotlinx.android.synthetic.main.view_device_linking.view.explanationTextView
+import kotlinx.android.synthetic.main.view_device_linking.view.titleTextView
 import network.loki.messenger.R
+import org.thoughtcrime.securesms.qr.QrCode
+import org.thoughtcrime.securesms.util.ServiceUtil
 import org.thoughtcrime.securesms.util.TextSecurePreferences
 import org.whispersystems.signalservice.loki.api.PairingAuthorisation
 import org.whispersystems.signalservice.loki.crypto.MnemonicCodec
@@ -55,6 +59,19 @@ class DeviceLinkingView private constructor(context: Context, attrs: AttributeSe
         }
         authorizeButton.visibility = View.GONE
         authorizeButton.setOnClickListener { authorizePairing() }
+
+        // QR Code
+        spinner.visibility = if (mode == Mode.Master) View.GONE else View.VISIBLE
+        qrCodeImageView.visibility = if (mode == Mode.Master) View.VISIBLE else View.GONE
+        if (mode == Mode.Master) {
+            val hexEncodedPublicKey = TextSecurePreferences.getLocalNumber(context)
+            val displayMetrics = DisplayMetrics()
+            ServiceUtil.getWindowManager(context).defaultDisplay.getMetrics(displayMetrics)
+            val size = displayMetrics.widthPixels - 2 * toPx(96, resources)
+            val qrCode = QrCode.create(hexEncodedPublicKey, size)
+            qrCodeImageView.setImageBitmap(qrCode)
+        }
+
         cancelButton.setOnClickListener { cancel() }
     }
     // endregion
@@ -64,6 +81,7 @@ class DeviceLinkingView private constructor(context: Context, attrs: AttributeSe
         if (mode != Mode.Master || pairingAuthorisation.type != PairingAuthorisation.Type.REQUEST || this.pairingAuthorisation != null) { return }
         this.pairingAuthorisation = pairingAuthorisation
         spinner.visibility = View.GONE
+        qrCodeImageView.visibility = View.GONE
         val titleTextViewLayoutParams = titleTextView.layoutParams as LayoutParams
         titleTextViewLayoutParams.topMargin = toPx(16, resources)
         titleTextView.layoutParams = titleTextViewLayoutParams

src/org/thoughtcrime/securesms/loki/ScanQRCodeFragment.kt

@@ -3,6 +3,7 @@ package org.thoughtcrime.securesms.loki
 import android.content.res.Configuration
 import android.os.Bundle
 import android.support.v4.app.Fragment
+import android.support.v7.app.AppCompatActivity
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -14,8 +15,15 @@ import org.thoughtcrime.securesms.qr.ScanningThread
 
 class ScanQRCodeFragment : Fragment() {
     private val scanningThread = ScanningThread()
+    private var viewCreated = false
     var scanListener: ScanListener? = null
         set(value) { field = value; scanningThread.setScanListener(scanListener) }
+    var mode: Mode = Mode.NewConversation
+        set(value) { field = value; updateDescription(); }
+
+    // region Types
+    enum class Mode { NewConversation, LinkDevice }
+    // endregion
 
     override fun onCreateView(layoutInflater: LayoutInflater, viewGroup: ViewGroup?, bundle: Bundle?): View? {
         return layoutInflater.inflate(R.layout.fragment_scan_qr_code, viewGroup, false)
@@ -23,10 +31,12 @@ class ScanQRCodeFragment : Fragment() {
 
     override fun onViewCreated(view: View, bundle: Bundle?) {
         super.onViewCreated(view, bundle)
+        viewCreated = true
         when (resources.configuration.orientation) {
             Configuration.ORIENTATION_LANDSCAPE -> overlayView.orientation = LinearLayout.HORIZONTAL
             else -> overlayView.orientation = LinearLayout.VERTICAL
         }
+        updateDescription()
     }
 
     override fun onResume() {
@@ -35,8 +45,10 @@ class ScanQRCodeFragment : Fragment() {
         this.cameraView.onResume()
         this.cameraView.setPreviewCallback(scanningThread)
         this.scanningThread.start()
-        val activity = activity as NewConversationActivity
+        if (activity is AppCompatActivity) {
-        activity.supportActionBar!!.setTitle(R.string.fragment_scan_qr_code_title)
+            val activity = activity as AppCompatActivity
+            activity.supportActionBar?.setTitle(R.string.fragment_scan_qr_code_title)
+        }
     }
 
     override fun onPause() {
@@ -55,4 +67,13 @@ class ScanQRCodeFragment : Fragment() {
         cameraView.onResume()
         cameraView.setPreviewCallback(scanningThread)
     }
+
+    fun updateDescription() {
+        if (!viewCreated) { return }
+        val text = when (mode) {
+            Mode.NewConversation -> R.string.fragment_scan_qr_code_explanation_new_conversation
+            Mode.LinkDevice -> R.string.fragment_scan_qr_code_explanation_link_device
+        }
+        descriptionTextView.setText(text)
+    }
 }

src/org/thoughtcrime/securesms/loki/SeedActivity.kt

@@ -1,11 +1,13 @@
 package org.thoughtcrime.securesms.loki
 
+import android.Manifest
 import android.content.ClipData
 import android.content.ClipboardManager
 import android.content.Context
 import android.content.Intent
 import android.os.AsyncTask
 import android.os.Bundle
+import android.support.v4.app.FragmentManager
 import android.view.View
 import android.view.inputmethod.InputMethodManager
 import android.widget.Toast
@@ -19,6 +21,8 @@ import org.thoughtcrime.securesms.database.Address
 import org.thoughtcrime.securesms.database.DatabaseFactory
 import org.thoughtcrime.securesms.database.IdentityDatabase
 import org.thoughtcrime.securesms.logging.Log
+import org.thoughtcrime.securesms.permissions.Permissions
+import org.thoughtcrime.securesms.qr.ScanListener
 import org.thoughtcrime.securesms.util.Hex
 import org.thoughtcrime.securesms.util.TextSecurePreferences
 import org.whispersystems.curve25519.Curve25519
@@ -32,7 +36,7 @@ import org.whispersystems.signalservice.loki.utilities.retryIfNeeded
 import java.io.File
 import java.io.FileOutputStream
 
-class SeedActivity : BaseActionBarActivity(), DeviceLinkingDelegate {
+class SeedActivity : BaseActionBarActivity(), DeviceLinkingDelegate, ScanListener {
     private lateinit var languageFileDirectory: File
     private var mode = Mode.Register
         set(newValue) { field = newValue; updateUI() }
@@ -57,6 +61,23 @@ class SeedActivity : BaseActionBarActivity(), DeviceLinkingDelegate {
         toggleRestoreModeButton.setOnClickListener { mode = Mode.Restore }
         toggleLinkModeButton.setOnClickListener { mode = Mode.Link }
         mainButton.setOnClickListener { handleMainButtonTapped() }
+        scanQRButton.setOnClickListener {
+            Permissions.with(this)
+                    .request(Manifest.permission.CAMERA)
+                    .ifNecessary()
+                    .withPermanentDenialDialog(getString(R.string.fragment_scan_qr_code_camera_permission_dialog_message))
+                    .onAllGranted {
+                        val fragment = ScanQRCodeFragment()
+                        fragment.mode = ScanQRCodeFragment.Mode.LinkDevice
+                        fragment.scanListener = this
+                        supportFragmentManager.beginTransaction().replace(android.R.id.content, fragment).addToBackStack("QR").commitAllowingStateLoss()
+                        publicKeyEditText.clearFocus()
+                        val inputMethodManager = getSystemService(INPUT_METHOD_SERVICE) as InputMethodManager
+                        inputMethodManager.hideSoftInputFromWindow(publicKeyEditText.windowToken, 0)
+                    }
+                    .onAnyDenied { Toast.makeText(this, R.string.fragment_scan_qr_code_camera_permission_dialog_message, Toast.LENGTH_SHORT).show() }
+                    .execute()
+        }
         Analytics.shared.track("Seed Screen Viewed")
     }
     // endregion
@@ -106,6 +127,7 @@ class SeedActivity : BaseActionBarActivity(), DeviceLinkingDelegate {
         mnemonicEditText.visibility = restoreModeVisibility
         linkExplanationTextView.visibility = linkModeVisibility
         publicKeyEditText.visibility = linkModeVisibility
+        scanQRButton.visibility = linkModeVisibility
         toggleRegisterModeButton.visibility = if (mode != Mode.Register) View.VISIBLE else View.GONE
         toggleRestoreModeButton.visibility = if (mode != Mode.Restore) View.VISIBLE else View.GONE
         toggleLinkModeButton.visibility = if (mode != Mode.Link) View.VISIBLE else View.GONE
@@ -236,4 +258,14 @@ class SeedActivity : BaseActionBarActivity(), DeviceLinkingDelegate {
         TextSecurePreferences.setPromptedPushRegistration(this, false)
     }
     // endregion
+    override fun onQrDataFound(data: String?) {
+        runOnUiThread {
+            if (data != null && PublicKeyValidation.isValid(data.trim())) {
+                publicKeyEditText.setText(data.trim())
+                supportFragmentManager.popBackStackImmediate("QR", FragmentManager.POP_BACK_STACK_INCLUSIVE)
+                handleMainButtonTapped()
+            }
+        }
+    }
+    // endregion
 }

src/org/thoughtcrime/securesms/qr/QrCode.java

@@ -5,12 +5,15 @@ import android.graphics.Color;
 import android.support.annotation.NonNull;
 
 import com.google.zxing.BarcodeFormat;
+import com.google.zxing.EncodeHintType;
 import com.google.zxing.WriterException;
 import com.google.zxing.common.BitMatrix;
 import com.google.zxing.qrcode.QRCodeWriter;
 
 import org.thoughtcrime.securesms.logging.Log;
 
+import java.util.HashMap;
+
 public class QrCode {
 
   public static final String TAG = QrCode.class.getSimpleName();
@@ -18,10 +21,12 @@ public class QrCode {
   public static @NonNull Bitmap create(String data) {
     return create(data, 1024);
   }
-
+  public static @NonNull Bitmap create(String data, int size) { return create(data, size, 2); }
-  public static @NonNull Bitmap create(String data, int size) {
+  public static @NonNull Bitmap create(String data, int size, int margin) {
     try {
-      BitMatrix result = new QRCodeWriter().encode(data, BarcodeFormat.QR_CODE, size, size);
+      HashMap<EncodeHintType, Integer> hintMap = new HashMap<>();
+      hintMap.put(EncodeHintType.MARGIN, margin);
+      BitMatrix result = new QRCodeWriter().encode(data, BarcodeFormat.QR_CODE, size, size, hintMap);
       Bitmap    bitmap = Bitmap.createBitmap(result.getWidth(), result.getHeight(), Bitmap.Config.ARGB_8888);
 
       for (int y = 0; y < result.getHeight(); y++) {