Fix up navigation

src/main/res/layout/layout_scanner.xml

@@ -1,15 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
-
-<FrameLayout
+<LinearLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
-    android:layout_height="match_parent">
-
-    <FrameLayout
-        android:id="@+id/content_frame"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent" />
-
+    android:layout_height="match_parent"
+    android:orientation="vertical">
     <include layout="@layout/toolbar_light_dark" />
-</FrameLayout>
+    <me.dm7.barcodescanner.zxing.ZXingScannerView android:id="@+id/scanner"
+                                                  android:layout_width="match_parent"
+                                                  android:layout_height="0dp"
+                                                  android:layout_weight="1"/>
+</LinearLayout>

src/main/scala/com/github/shadowsocks/AppManager.scala

@@ -42,6 +42,7 @@ package com.github.shadowsocks
 import java.util.concurrent.atomic.AtomicBoolean
 
 import android.Manifest.permission
+import android.app.TaskStackBuilder
 import android.content._
 import android.content.pm.PackageManager
 import android.graphics.drawable.Drawable
@@ -220,9 +221,11 @@ class AppManager extends AppCompatActivity with OnMenuItemClickListener {
     toolbar = findViewById(R.id.toolbar).asInstanceOf[Toolbar]
     toolbar.setTitle(R.string.proxied_apps)
     toolbar.setNavigationIcon(R.drawable.abc_ic_ab_back_material)
-    toolbar.setNavigationOnClickListener((v: View) => {
+    toolbar.setNavigationOnClickListener(_ => {
       val intent = getParentActivityIntent
-      if (intent == null) finish else navigateUpTo(intent)
+      if (shouldUpRecreateTask(intent) || isTaskRoot)
+        TaskStackBuilder.create(this).addNextIntentWithParentStack(intent).startActivities()
+      else finish()
     })
     toolbar.inflateMenu(R.menu.app_manager_menu)
     toolbar.setOnMenuItemClickListener(this)

src/main/scala/com/github/shadowsocks/ProfileManagerActivity.scala

@@ -2,7 +2,7 @@ package com.github.shadowsocks
 
 import java.nio.charset.Charset
 
-import android.app.Activity
+import android.app.{Activity, TaskStackBuilder}
 import android.content._
 import android.content.pm.PackageManager
 import android.nfc.NfcAdapter.CreateNdefMessageCallback
@@ -203,9 +203,11 @@ final class ProfileManagerActivity extends AppCompatActivity with OnMenuItemClic
     val toolbar = findViewById(R.id.toolbar).asInstanceOf[Toolbar]
     toolbar.setTitle(R.string.profiles)
     toolbar.setNavigationIcon(R.drawable.ic_navigation_close)
-    toolbar.setNavigationOnClickListener((v: View) => {
+    toolbar.setNavigationOnClickListener(_ => {
       val intent = getParentActivityIntent
-      if (intent == null) finish else navigateUpTo(intent)
+      if (shouldUpRecreateTask(intent) || isTaskRoot)
+        TaskStackBuilder.create(this).addNextIntentWithParentStack(intent).startActivities()
+      else finish()
     })
     toolbar.inflateMenu(R.menu.profile_manager_menu)
     toolbar.setOnMenuItemClickListener(this)

src/main/scala/com/github/shadowsocks/ScannerActivity.scala

@@ -1,6 +1,6 @@
 package com.github.shadowsocks
 
-import android.app.Activity
+import android.app.{Activity, TaskStackBuilder}
 import android.content.Intent
 import android.content.pm.{PackageManager, ShortcutManager}
 import android.os.{Build, Bundle}
@@ -8,16 +8,18 @@ import android.support.v4.app.ActivityCompat
 import android.support.v4.content.ContextCompat
 import android.support.v7.app.AppCompatActivity
 import android.support.v7.widget.Toolbar
-import android.view.{MenuItem, ViewGroup}
 import android.widget.Toast
 import com.google.zxing.Result
 import me.dm7.barcodescanner.zxing.ZXingScannerView
 
+object ScannerActivity {
+  private final val MY_PERMISSIONS_REQUEST_CAMERA = 1
+}
+
 class ScannerActivity extends AppCompatActivity with ZXingScannerView.ResultHandler {
+  import ScannerActivity._
 
-  val MY_PERMISSIONS_REQUEST_CAMERA = 1
-
-  var scannerView: ZXingScannerView = _
+  private var scannerView: ZXingScannerView = _
 
   override def onRequestPermissionsResult(requestCode: Int, permissions: Array[String],
     grantResults: Array[Int]) {
@@ -34,14 +36,21 @@ class ScannerActivity extends AppCompatActivity with ZXingScannerView.ResultHand
     }
   }
 
+  def navigateUp() {
+    val intent = getParentActivityIntent
+    if (shouldUpRecreateTask(intent) || isTaskRoot)
+      TaskStackBuilder.create(this).addNextIntentWithParentStack(intent).startActivities()
+    else finish()
+  }
+
   override def onCreate(state: Bundle) {
     super.onCreate(state)
     setContentView(R.layout.layout_scanner)
-    setupToolbar()
-
-    scannerView = new ZXingScannerView(this)
-    val contentFrame = findViewById(R.id.content_frame).asInstanceOf[ViewGroup]
-    contentFrame.addView(scannerView)
+    val toolbar = findViewById(R.id.toolbar).asInstanceOf[Toolbar]
+    toolbar.setTitle(getTitle)
+    toolbar.setNavigationIcon(R.drawable.abc_ic_ab_back_material)
+    toolbar.setNavigationOnClickListener(_ => navigateUp())
+    scannerView = findViewById(R.id.scanner).asInstanceOf[ZXingScannerView]
     if (Build.VERSION.SDK_INT >= 25) getSystemService(classOf[ShortcutManager]).reportShortcutUsed("scan")
   }
 
@@ -67,29 +76,7 @@ class ScannerActivity extends AppCompatActivity with ZXingScannerView.ResultHand
     val intent = new Intent()
     intent.putExtra("uri", rawResult.getText)
     setResult(Activity.RESULT_OK, intent)
-    navigateUpTo(getParentActivityIntent)
+    navigateUp()
   }
-
-  def setupToolbar() {
-    val toolbar = findViewById(R.id.toolbar).asInstanceOf[Toolbar]
-    setSupportActionBar(toolbar)
-    val ab = getSupportActionBar()
-    if (ab != null) {
-      ab.setDisplayHomeAsUpEnabled(true)
-    }
-  }
-
-  override def onOptionsItemSelected(item: MenuItem): Boolean = {
-    item.getItemId() match {
-      // Respond to the action bar's Up/Home button
-      case android.R.id.home =>
-        setResult(Activity.RESULT_CANCELED, new Intent())
-        finish()
-        return true
-      case _ => // Do nothing
-    }
-    return super.onOptionsItemSelected(item)
-  }
-
 }