Single-instance app, talker info in notification

- MainActivity singleTask, SplashActivity singleTop: re-launching from
  launcher or notification never creates a second instance
- Splash skips the 4s animation when the main screen is already open
- Foreground notification shows 'Говорит: CALLSIGN' / 'Последний:
  CALLSIGN'; tapping it brings the app back to the front

app/src/main/AndroidManifest.xml

@@ -28,6 +28,7 @@
         <activity
             android:name=".SplashActivity"
             android:exported="true"
+            android:launchMode="singleTop"
             android:screenOrientation="portrait"
             android:theme="@style/Theme.SvxRemote">
             <intent-filter>
@@ -39,6 +40,7 @@
         <activity
             android:name=".MainActivity"
             android:exported="false"
+            android:launchMode="singleTask"
             android:screenOrientation="portrait"
             android:configChanges="orientation|screenSize|keyboardHidden" />
 

app/src/main/java/ru/ua1zbe/svxremote/MainActivity.kt

@@ -78,6 +78,7 @@ class MainActivity : Activity(), SvxService.Listener {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
+        SplashActivity.mainAlive = true
         setContentView(R.layout.activity_main)
         window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
         checkForUpdates()
@@ -174,6 +175,7 @@ class MainActivity : Activity(), SvxService.Listener {
 
     override fun onDestroy() {
         super.onDestroy()
+        SplashActivity.mainAlive = false
         svc?.listener = null
         unbindService(svcConn)
     }

app/src/main/java/ru/ua1zbe/svxremote/SplashActivity.kt

@@ -9,15 +9,23 @@ import android.view.animation.AccelerateDecelerateInterpolator
 /** Красивая заставка с плавным появлением логотипа. */
 class SplashActivity : Activity() {
 
+    companion object {
+        @Volatile
+        var mainAlive = false
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
+        if (mainAlive) {
+            openMain()
+            return
+        }
         setContentView(R.layout.activity_splash)
 
         val title = findViewById<View>(R.id.splash_title)
         val subtitle = findViewById<View>(R.id.splash_subtitle)
         val line = findViewById<View>(R.id.splash_line)
 
-        val baseAlpha = title.alpha
         title.alpha = 0f
         subtitle.alpha = 0f
         line.alpha = 0f
@@ -44,10 +52,19 @@ class SplashActivity : Activity() {
             .start()
 
         window.decorView.postDelayed({
-            val intent = Intent(this, MainActivity::class.java)
-            startActivity(intent)
-            overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out)
-            finish()
+            openMain()
         }, 4000)
     }
+
+    private fun openMain() {
+        val intent = Intent(this, MainActivity::class.java)
+            .addFlags(
+                Intent.FLAG_ACTIVITY_NEW_TASK or
+                    Intent.FLAG_ACTIVITY_CLEAR_TOP or
+                    Intent.FLAG_ACTIVITY_SINGLE_TOP
+            )
+        startActivity(intent)
+        overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out)
+        finish()
+    }
 }

app/src/main/java/ru/ua1zbe/svxremote/SvxService.kt

@@ -3,6 +3,7 @@ package ru.ua1zbe.svxremote
 import android.app.Notification
 import android.app.NotificationChannel
 import android.app.NotificationManager
+import android.app.PendingIntent
 import android.app.Service
 import android.content.Intent
 import android.os.Binder
@@ -53,11 +54,22 @@ class SvxService : Service(), ReflectorClient.Callbacks {
         nm.createNotificationChannel(
             NotificationChannel("svx", "SVXRemote", NotificationManager.IMPORTANCE_LOW)
         )
+        updateNotification(getString(R.string.notif_connected))
+    }
+
+    private fun updateNotification(text: String) {
+        val contentIntent = PendingIntent.getActivity(
+            this, 0,
+            Intent(this, MainActivity::class.java)
+                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_SINGLE_TOP),
+            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
+        )
         val n = Notification.Builder(this, "svx")
             .setContentTitle("SVXRemote")
-            .setContentText(getString(R.string.notif_connected))
+            .setContentText(text)
             .setSmallIcon(android.R.drawable.ic_menu_call)
             .setOngoing(true)
+            .setContentIntent(contentIntent)
             .build()
         startForeground(1, n)
     }
@@ -86,7 +98,10 @@ class SvxService : Service(), ReflectorClient.Callbacks {
 
     override fun onState(state: Int, detail: String?) {
         when (state) {
-            ReflectorClient.STATE_READY -> engine.startDecoder()
+            ReflectorClient.STATE_READY -> {
+                updateNotification(getString(R.string.notif_connected))
+                engine.startDecoder()
+            }
             ReflectorClient.STATE_DISCONNECTED -> {
                 engine.stopDecoder()
                 stopForeground(STOP_FOREGROUND_REMOVE)
@@ -100,10 +115,12 @@ class SvxService : Service(), ReflectorClient.Callbacks {
     }
 
     override fun onTalkerStart(tg: Long, callsign: String) {
+        updateNotification(getString(R.string.notif_talking, callsign))
         listener?.onTalkerStart(tg, callsign)
     }
 
     override fun onTalkerStop(tg: Long, callsign: String) {
+        updateNotification(getString(R.string.notif_last_talker, callsign))
         listener?.onTalkerStop(tg, callsign)
     }
 

app/src/main/res/values/strings.xml

@@ -34,6 +34,8 @@
     <string name="status_auth_failed">Ошибка авторизации</string>
     <string name="status_error">Ошибка: %1$s</string>
     <string name="notif_connected">Соединение с рефлектором активно</string>
+    <string name="notif_talking">Говорит: %1$s</string>
+    <string name="notif_last_talker">Последний: %1$s</string>
 
     <string name="btn_connect">Подключиться</string>
     <string name="btn_disconnect">Отключиться</string>