PiP

Signed-off-by: Anton Afanasyeu <a.afanasieff@gmail.com>

app/src/main/java/com/foxx/androidcast/AppPreferences.java

@@ -20,6 +20,8 @@ public final class AppPreferences {
     private static final String KEY_PLAY_INCOMING_AUDIO = "play_incoming_audio";
     private static final String KEY_DEV_RECEIVER_DEBUG_OVERLAY = "dev_receiver_debug_overlay";
     private static final String KEY_DEV_GRAB_SESSION_STATS = "dev_grab_session_stats";
+    private static final String KEY_RECEIVER_PIP_USER_DEFINED = "receiver_pip_user_defined";
+    private static final String KEY_RECEIVER_PIP_ENABLED = "receiver_pip_enabled";
 
     private static final String PREFIX_SENDER = "sender_";
     private static final String PREFIX_RECEIVER = "receiver_";
@@ -112,6 +114,38 @@ public final class AppPreferences {
         prefs(context).edit().putBoolean(KEY_DEV_GRAB_SESSION_STATS, grab).apply();
     }
 
+    /**
+     * Receiver PiP: user toggle when set; otherwise derived from PiP support + notifications permission.
+     */
+    public static boolean isReceiverPipEnabled(Context context) {
+        if (prefs(context).getBoolean(KEY_RECEIVER_PIP_USER_DEFINED, false)) {
+            return prefs(context).getBoolean(KEY_RECEIVER_PIP_ENABLED, false);
+        }
+        return defaultReceiverPipEnabled(context);
+    }
+
+    /** Value shown in settings before the user changes the toggle. */
+    public static boolean getReceiverPipEffective(Context context) {
+        return isReceiverPipEnabled(context);
+    }
+
+    public static boolean isReceiverPipUserDefined(Context context) {
+        return prefs(context).getBoolean(KEY_RECEIVER_PIP_USER_DEFINED, false);
+    }
+
+    public static void setReceiverPipUserChoice(Context context, boolean enabled) {
+        prefs(context).edit()
+                .putBoolean(KEY_RECEIVER_PIP_USER_DEFINED, true)
+                .putBoolean(KEY_RECEIVER_PIP_ENABLED, enabled)
+                .apply();
+    }
+
+    private static boolean defaultReceiverPipEnabled(Context context) {
+        return PictureInPictureHelper.isSupported()
+                && PictureInPictureHelper.isAllowedForApp(context)
+                && PermissionHelper.hasReceiverPlaybackReady(context);
+    }
+
     public static CastSettings loadSenderDefaults(Context context) {
         CastSettings s = new CastSettings();
         applyStoredCastSettings(context, PREFIX_SENDER, s);

app/src/main/java/com/foxx/androidcast/CastConfig.java

@@ -5,10 +5,16 @@ public final class CastConfig {
     public static final int DISCOVERY_PORT = 41234;
     /** One UDP browse pass duration (sender shows countdown on Refresh). */
     public static final long DISCOVERY_SCAN_PASS_MS = 30_000;
+    /** Fast scan when user taps Refresh (UDP burst + NSD). */
+    public static final long DISCOVERY_BURST_MS = 5_000;
     /** Idle gap between automatic browse passes. */
     public static final long DISCOVERY_PAUSE_MS = 30_000;
     /** How often the sender broadcasts a discover probe during a scan pass. */
     public static final long DISCOVERY_PROBE_INTERVAL_MS = 1_000;
+    /** Probe interval during burst scan. */
+    public static final long DISCOVERY_BURST_PROBE_MS = 250;
+    /** NSD service type for LAN discovery (in addition to UDP). */
+    public static final String NSD_SERVICE_TYPE = "_androidcast._udp.";
     public static final int CAST_PORT = 41235;
     public static final String DISCOVERY_MAGIC = "ACAST1";
 

app/src/main/java/com/foxx/androidcast/CastSettingsBinder.java

@@ -103,6 +103,7 @@ public final class CastSettingsBinder {
     }
 
     public static void bindReceiver(AppCompatActivity activity, CastSettings settings) {
+        bindReceiverPip(activity);
         bindTransport(activity, settings, R.id.spinner_receiver_transport, true);
         bindVideoCodec(activity, settings, R.id.spinner_receiver_video_codec);
         bindNetworkAdoption(activity, settings, R.id.spinner_receiver_network);
@@ -129,6 +130,7 @@ public final class CastSettingsBinder {
     }
 
     public static void saveReceiver(AppCompatActivity activity, CastSettings settings) {
+        saveReceiverPip(activity);
         readTransport(activity, settings, R.id.spinner_receiver_transport);
         readVideoCodec(activity, settings, R.id.spinner_receiver_video_codec);
         readNetworkAdoption(activity, settings, R.id.spinner_receiver_network);
@@ -312,6 +314,37 @@ public final class CastSettingsBinder {
         readEnumSpinner(activity.findViewById(R.id.spinner_sender_resolution), settings::setResolution);
     }
 
+    public static void bindReceiverPip(AppCompatActivity activity) {
+        CheckBox pip = activity.findViewById(R.id.check_receiver_pip);
+        if (pip == null) {
+            return;
+        }
+        boolean supported = PictureInPictureHelper.isSupported();
+        pip.setEnabled(supported);
+        pip.setOnCheckedChangeListener(null);
+        pip.setChecked(AppPreferences.getReceiverPipEffective(activity));
+        pip.setOnCheckedChangeListener((btn, checked) ->
+                AppPreferences.setReceiverPipUserChoice(activity, checked));
+        if (!supported) {
+            pip.setChecked(false);
+        }
+    }
+
+    /** Re-apply permission-derived default when the user has not chosen explicitly. */
+    public static void refreshReceiverPipFromPermissions(AppCompatActivity activity) {
+        if (AppPreferences.isReceiverPipUserDefined(activity)) {
+            return;
+        }
+        bindReceiverPip(activity);
+    }
+
+    private static void saveReceiverPip(AppCompatActivity activity) {
+        CheckBox pip = activity.findViewById(R.id.check_receiver_pip);
+        if (pip != null && pip.isEnabled()) {
+            AppPreferences.setReceiverPipUserChoice(activity, pip.isChecked());
+        }
+    }
+
     private static void bindReceiverDisplay(AppCompatActivity activity, CastSettings settings) {
         Spinner spinner = activity.findViewById(R.id.spinner_receiver_resolution);
         CastSettings.ReceiverDisplayResolution[] modes = CastSettings.ReceiverDisplayResolution.values();

app/src/main/java/com/foxx/androidcast/CastSettingsFragment.java

@@ -119,6 +119,12 @@ public class CastSettingsFragment extends Fragment {
         });
     }
 
+    @Override
+    public void onResume() {
+        super.onResume();
+        CastSettingsBinder.refreshReceiverPipFromPermissions((AppCompatActivity) requireActivity());
+    }
+
     @Override
     public void onPause() {
         saveAll();

app/src/main/java/com/foxx/androidcast/PermissionHelper.java

@@ -123,8 +123,8 @@ public final class PermissionHelper {
     }
 
     /** Permissions needed before receiver cast / PiP (notifications for foreground service). */
-    public static boolean hasReceiverPlaybackReady(Activity activity) {
-        return missingForReceiverPlayback(activity).isEmpty();
+    public static boolean hasReceiverPlaybackReady(android.content.Context context) {
+        return missingForReceiverPlayback(context).isEmpty();
     }
 
     public static void remindForReceiverPlayback(Activity activity) {
@@ -148,13 +148,15 @@ public final class PermissionHelper {
                 .show();
     }
 
-    private static List<PermissionItem> missingForReceiverPlayback(Activity activity) {
+    private static List<PermissionItem> missingForReceiverPlayback(android.content.Context context) {
         List<PermissionItem> needed = new ArrayList<>();
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
-            if (ContextCompat.checkSelfPermission(activity, Manifest.permission.POST_NOTIFICATIONS)
+            if (ContextCompat.checkSelfPermission(context, Manifest.permission.POST_NOTIFICATIONS)
                     != PackageManager.PERMISSION_GRANTED) {
-                needed.add(new PermissionItem(Manifest.permission.POST_NOTIFICATIONS,
-                        activity.getString(R.string.permission_notifications_cast), true));
+                String label = context instanceof Activity
+                        ? ((Activity) context).getString(R.string.permission_notifications_cast)
+                        : "Notifications (cast status)";
+                needed.add(new PermissionItem(Manifest.permission.POST_NOTIFICATIONS, label, true));
             }
         }
         return needed;

app/src/main/java/com/foxx/androidcast/discovery/DiscoveryManager.java

@@ -56,6 +56,8 @@ public class DiscoveryManager {
         public final long protoVersion;
         /** SHA-256 hex of receiver PIN, empty if anonymous. */
         public final String pinAuth;
+        /** Shown from {@link PinnedReceiversStore} at top of sender list. */
+        public boolean pinnedRecent;
 
         public DiscoveredDevice(String name, String host, int port, String transport, long lastSeenMs) {
             this(name, host, port, transport, lastSeenMs, 0, 0, 0, 0L, "");
@@ -96,6 +98,8 @@ public class DiscoveryManager {
     private final Object lockGuard = new Object();
     private WifiManager.MulticastLock multicastLock;
     private int multicastHolds;
+    private boolean burstScan;
+    private NsdCastDiscovery nsdDiscovery;
 
     public DiscoveryManager(Context context) {
         this.appContext = context.getApplicationContext();
@@ -110,11 +114,18 @@ public class DiscoveryManager {
     }
 
     public void startBrowsing() {
+        startBrowsing(false);
+    }
+
+    /** @param burst shorter UDP pass + NSD (user Refresh). */
+    public void startBrowsing(boolean burst) {
         if (!running.compareAndSet(false, true)) {
             return;
         }
+        burstScan = burst;
         purgeSelfFromDeviceMap();
         notifyScanStarted();
+        startNsdBrowse();
         executor.execute(this::browseLoop);
     }
 
@@ -124,6 +135,8 @@ public class DiscoveryManager {
      */
     public void stop() {
         running.set(false);
+        stopNsdBrowse();
+        stopNsdRegister();
         DatagramSocket toClose = socket;
         socket = null;
         if (toClose != null) {
@@ -154,9 +167,25 @@ public class DiscoveryManager {
         if (!running.compareAndSet(false, true)) {
             return;
         }
+        String pinHash = com.foxx.androidcast.PinAuth.isProtected(pin)
+                ? com.foxx.androidcast.PinAuth.hash(pin) : "";
+        startNsdRegister(deviceName, port, transport, pinHash);
         executor.execute(() -> announceLoop(context, deviceName, port, transport, listening, pin));
     }
 
+    /** Merge device from NSD or pinned list into the browse map. */
+    public void upsertExternal(DiscoveredDevice device) {
+        if (device == null || device.host == null || device.host.isEmpty()) {
+            return;
+        }
+        if (DiscoverySelfFilter.isSelf(appContext, device.host, null)) {
+            return;
+        }
+        String key = device.host + ":" + device.port;
+        devices.put(key, device);
+        notifyListener();
+    }
+
     public void startAnnouncing(String deviceName, int port, String transport, boolean listening) {
         startAnnouncing(appContext, deviceName, port, transport, listening, "");
     }
@@ -170,13 +199,16 @@ public class DiscoveryManager {
             sock.setBroadcast(true);
             sock.setSoTimeout(300);
             byte[] buf = new byte[1024];
-            long deadline = System.currentTimeMillis() + CastConfig.DISCOVERY_SCAN_PASS_MS;
+            long passMs = burstScan ? CastConfig.DISCOVERY_BURST_MS : CastConfig.DISCOVERY_SCAN_PASS_MS;
+            long probeInterval = burstScan ? CastConfig.DISCOVERY_BURST_PROBE_MS
+                    : CastConfig.DISCOVERY_PROBE_INTERVAL_MS;
+            long deadline = System.currentTimeMillis() + passMs;
             long nextProbeMs = System.currentTimeMillis();
             while (running.get() && System.currentTimeMillis() < deadline) {
                 long now = System.currentTimeMillis();
                 if (now >= nextProbeMs) {
                     sendDiscoveryProbe(sock);
-                    nextProbeMs = now + CastConfig.DISCOVERY_PROBE_INTERVAL_MS;
+                    nextProbeMs = now + probeInterval;
                 }
                 DatagramPacket packet = new DatagramPacket(buf, buf.length);
                 try {
@@ -451,6 +483,32 @@ public class DiscoveryManager {
         }
     }
 
+    private void startNsdBrowse() {
+        if (nsdDiscovery == null) {
+            nsdDiscovery = new NsdCastDiscovery(appContext, this::upsertExternal);
+        }
+        nsdDiscovery.startDiscovering();
+    }
+
+    private void stopNsdBrowse() {
+        if (nsdDiscovery != null) {
+            nsdDiscovery.stopDiscovering();
+        }
+    }
+
+    private void startNsdRegister(String deviceName, int port, String transport, String pinAuth) {
+        if (nsdDiscovery == null) {
+            nsdDiscovery = new NsdCastDiscovery(appContext, this::upsertExternal);
+        }
+        nsdDiscovery.register(deviceName, port, transport, pinAuth);
+    }
+
+    public void stopNsdRegister() {
+        if (nsdDiscovery != null) {
+            nsdDiscovery.unregister();
+        }
+    }
+
     private void releaseMulticastLock() {
         synchronized (lockGuard) {
             if (multicastLock == null || multicastHolds <= 0) {

app/src/main/java/com/foxx/androidcast/discovery/NsdCastDiscovery.java

@@ -0,0 +1,196 @@
+package com.foxx.androidcast.discovery;
+
+import android.content.Context;
+import android.net.nsd.NsdManager;
+import android.net.nsd.NsdServiceInfo;
+import android.os.Build;
+import android.util.Log;
+
+import com.foxx.androidcast.CastConfig;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * Android NSD (mDNS) discovery/advertise alongside UDP broadcast.
+ * TXT: port, transport, pin_auth (optional).
+ */
+public final class NsdCastDiscovery {
+    private static final String TAG = "NsdCastDiscovery";
+
+    public interface Host {
+        void onNsdDeviceFound(DiscoveryManager.DiscoveredDevice device);
+    }
+
+    private final Context appContext;
+    private final Host host;
+    private NsdManager nsdManager;
+    private NsdManager.DiscoveryListener discoveryListener;
+    private NsdManager.RegistrationListener registrationListener;
+    private final AtomicBoolean discovering = new AtomicBoolean(false);
+
+    public NsdCastDiscovery(Context context, Host host) {
+        this.appContext = context.getApplicationContext();
+        this.host = host;
+    }
+
+    public void startDiscovering() {
+        if (!discovering.compareAndSet(false, true)) {
+            return;
+        }
+        nsdManager = (NsdManager) appContext.getSystemService(Context.NSD_SERVICE);
+        if (nsdManager == null) {
+            discovering.set(false);
+            return;
+        }
+        discoveryListener = new NsdManager.DiscoveryListener() {
+            @Override
+            public void onDiscoveryStarted(String serviceType) {
+                Log.d(TAG, "NSD discovery started");
+            }
+
+            @Override
+            public void onServiceFound(NsdServiceInfo service) {
+                if (service == null || service.getServiceType() == null) {
+                    return;
+                }
+                if (!service.getServiceType().contains("_androidcast")) {
+                    return;
+                }
+                nsdManager.resolveService(service, new NsdManager.ResolveListener() {
+                    @Override
+                    public void onResolveFailed(NsdServiceInfo serviceInfo, int errorCode) {
+                        Log.d(TAG, "NSD resolve failed: " + errorCode);
+                    }
+
+                    @Override
+                    public void onServiceResolved(NsdServiceInfo info) {
+                        publishResolved(info);
+                    }
+                });
+            }
+
+            @Override
+            public void onServiceLost(NsdServiceInfo service) {}
+
+            @Override
+            public void onDiscoveryStopped(String serviceType) {
+                discovering.set(false);
+            }
+
+            @Override
+            public void onStartDiscoveryFailed(String serviceType, int errorCode) {
+                Log.w(TAG, "NSD start failed: " + errorCode);
+                discovering.set(false);
+            }
+
+            @Override
+            public void onStopDiscoveryFailed(String serviceType, int errorCode) {
+                discovering.set(false);
+            }
+        };
+        try {
+            nsdManager.discoverServices(CastConfig.NSD_SERVICE_TYPE, NsdManager.PROTOCOL_DNS_SD,
+                    discoveryListener);
+        } catch (Exception e) {
+            Log.w(TAG, "NSD discover: " + e.getMessage());
+            discovering.set(false);
+        }
+    }
+
+    public void stopDiscovering() {
+        if (!discovering.get() || nsdManager == null || discoveryListener == null) {
+            discovering.set(false);
+            return;
+        }
+        try {
+            nsdManager.stopServiceDiscovery(discoveryListener);
+        } catch (Exception ignored) {
+        }
+        discoveryListener = null;
+        discovering.set(false);
+    }
+
+    public void register(String serviceName, int port, String transport, String pinAuth) {
+        nsdManager = (NsdManager) appContext.getSystemService(Context.NSD_SERVICE);
+        if (nsdManager == null) {
+            return;
+        }
+        NsdServiceInfo info = new NsdServiceInfo();
+        info.setServiceName(sanitizeServiceName(serviceName));
+        info.setServiceType(CastConfig.NSD_SERVICE_TYPE);
+        info.setPort(port);
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            info.setAttribute("transport", transport != null ? transport : CastConfig.DEFAULT_TRANSPORT);
+            if (pinAuth != null && !pinAuth.isEmpty()) {
+                info.setAttribute("pin_auth", pinAuth);
+            }
+        }
+        registrationListener = new NsdManager.RegistrationListener() {
+            @Override
+            public void onRegistrationFailed(NsdServiceInfo serviceInfo, int errorCode) {
+                Log.w(TAG, "NSD register failed: " + errorCode);
+            }
+
+            @Override
+            public void onUnregistrationFailed(NsdServiceInfo serviceInfo, int errorCode) {}
+
+            @Override
+            public void onServiceRegistered(NsdServiceInfo serviceInfo) {
+                Log.i(TAG, "NSD registered " + serviceInfo.getServiceName());
+            }
+
+            @Override
+            public void onServiceUnregistered(NsdServiceInfo serviceInfo) {}
+        };
+        try {
+            nsdManager.registerService(info, NsdManager.PROTOCOL_DNS_SD, registrationListener);
+        } catch (Exception e) {
+            Log.w(TAG, "NSD register: " + e.getMessage());
+        }
+    }
+
+    public void unregister() {
+        if (nsdManager == null || registrationListener == null) {
+            return;
+        }
+        try {
+            nsdManager.unregisterService(registrationListener);
+        } catch (Exception ignored) {
+        }
+        registrationListener = null;
+    }
+
+    private void publishResolved(NsdServiceInfo info) {
+        if (info == null || info.getHost() == null) {
+            return;
+        }
+        String hostAddress = info.getHost().getHostAddress();
+        int port = info.getPort();
+        if (port <= 0) {
+            port = CastConfig.CAST_PORT;
+        }
+        String transport = CastConfig.DEFAULT_TRANSPORT;
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            byte[] t = info.getAttributes().get("transport");
+            if (t != null) {
+                transport = new String(t).trim();
+            }
+        }
+        String name = info.getServiceName() != null ? info.getServiceName().replace('_', ' ') : hostAddress;
+        DiscoveryManager.DiscoveredDevice device = new DiscoveryManager.DiscoveredDevice(
+                name, hostAddress, port, transport, System.currentTimeMillis());
+        host.onNsdDeviceFound(device);
+    }
+
+    private static String sanitizeServiceName(String name) {
+        String s = name != null ? name : "AndroidCast";
+        s = s.replaceAll("[^a-zA-Z0-9-]", "");
+        if (s.length() < 1) {
+            s = "AndroidCast";
+        }
+        if (s.length() > 63) {
+            s = s.substring(0, 63);
+        }
+        return s;
+    }
+}

app/src/main/java/com/foxx/androidcast/discovery/PinnedReceiversStore.java

@@ -0,0 +1,90 @@
+package com.foxx.androidcast.discovery;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+
+import org.json.JSONArray;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Last successful cast targets shown at the top of the sender device list. */
+public final class PinnedReceiversStore {
+    private static final String PREFS = "androidcast_pinned_receivers";
+    private static final String KEY_ENTRIES = "entries";
+    private static final int MAX_PINNED = 5;
+
+    private PinnedReceiversStore() {}
+
+    public static void recordSuccess(Context context, DiscoveryManager.DiscoveredDevice device) {
+        if (context == null || device == null) {
+            return;
+        }
+        List<DiscoveryManager.DiscoveredDevice> list = load(context);
+        String key = device.host + ":" + device.port;
+        list.removeIf(d -> (d.host + ":" + d.port).equals(key));
+        DiscoveryManager.DiscoveredDevice copy = new DiscoveryManager.DiscoveredDevice(
+                device.name, device.host, device.port, device.transport, System.currentTimeMillis(),
+                device.videoCodecs, device.audioCodecs, device.placeholderId, device.protoVersion,
+                device.pinAuth);
+        copy.pinnedRecent = true;
+        list.add(0, copy);
+        while (list.size() > MAX_PINNED) {
+            list.remove(list.size() - 1);
+        }
+        save(context, list);
+    }
+
+    public static List<DiscoveryManager.DiscoveredDevice> load(Context context) {
+        List<DiscoveryManager.DiscoveredDevice> out = new ArrayList<>();
+        SharedPreferences p = context.getApplicationContext().getSharedPreferences(PREFS, Context.MODE_PRIVATE);
+        String raw = p.getString(KEY_ENTRIES, "[]");
+        try {
+            JSONArray arr = new JSONArray(raw);
+            for (int i = 0; i < arr.length(); i++) {
+                JSONObject o = arr.getJSONObject(i);
+                DiscoveryManager.DiscoveredDevice d = new DiscoveryManager.DiscoveredDevice(
+                        o.optString("name", "?"),
+                        o.optString("host", ""),
+                        o.optInt("port", 0),
+                        o.optString("transport", "udp"),
+                        o.optLong("last_seen_ms", 0L),
+                        o.optInt("video_codecs", 0),
+                        o.optInt("audio_codecs", 0),
+                        o.optInt("placeholder_id", 0),
+                        o.optLong("proto_version", 0L),
+                        o.optString("pin_auth", ""));
+                d.pinnedRecent = true;
+                if (!d.host.isEmpty() && d.port > 0) {
+                    out.add(d);
+                }
+            }
+        } catch (Exception ignored) {
+        }
+        return out;
+    }
+
+    private static void save(Context context, List<DiscoveryManager.DiscoveredDevice> list) {
+        JSONArray arr = new JSONArray();
+        for (DiscoveryManager.DiscoveredDevice d : list) {
+            try {
+                JSONObject o = new JSONObject();
+                o.put("name", d.name);
+                o.put("host", d.host);
+                o.put("port", d.port);
+                o.put("transport", d.transport);
+                o.put("last_seen_ms", d.lastSeenMs);
+                o.put("video_codecs", d.videoCodecs);
+                o.put("audio_codecs", d.audioCodecs);
+                o.put("placeholder_id", d.placeholderId);
+                o.put("proto_version", d.protoVersion);
+                o.put("pin_auth", d.pinAuth);
+                arr.put(o);
+            } catch (Exception ignored) {
+            }
+        }
+        context.getApplicationContext().getSharedPreferences(PREFS, Context.MODE_PRIVATE)
+                .edit().putString(KEY_ENTRIES, arr.toString()).apply();
+    }
+}

app/src/main/java/com/foxx/androidcast/receiver/ReceiverPlaybackActivity.java

@@ -247,7 +247,8 @@ public class ReceiverPlaybackActivity extends DrawerHostActivity {
     @Override
     public void onUserLeaveHint() {
         super.onUserLeaveHint();
-        if (castSessionActive && PermissionHelper.hasReceiverPlaybackReady(this)) {
+        if (castSessionActive && AppPreferences.isReceiverPipEnabled(this)
+                && PermissionHelper.hasReceiverPlaybackReady(this)) {
             tryEnterPictureInPicture();
         }
     }
@@ -403,7 +404,8 @@ public class ReceiverPlaybackActivity extends DrawerHostActivity {
         }
         videoWidth = width;
         videoHeight = height;
-        if (castSessionActive && PermissionHelper.hasReceiverPlaybackReady(this)) {
+        if (castSessionActive && AppPreferences.isReceiverPipEnabled(this)
+                && PermissionHelper.hasReceiverPlaybackReady(this)) {
             PictureInPictureHelper.applyParams(this, videoWidth, videoHeight);
         }
         applyAspectRatio();
@@ -509,7 +511,9 @@ public class ReceiverPlaybackActivity extends DrawerHostActivity {
 
     private void onCastSessionStarted() {
         castSessionActive = true;
-        PermissionHelper.remindForReceiverPlayback(this);
+        if (AppPreferences.isReceiverPipEnabled(this)) {
+            PermissionHelper.remindForReceiverPlayback(this);
+        }
         updatePipUi();
     }
 
@@ -522,7 +526,8 @@ public class ReceiverPlaybackActivity extends DrawerHostActivity {
         if (pipButton == null) {
             return;
         }
-        boolean show = castSessionActive && PictureInPictureHelper.isSupported()
+        boolean show = castSessionActive && AppPreferences.isReceiverPipEnabled(this)
+                && PictureInPictureHelper.isSupported()
                 && PermissionHelper.hasReceiverPlaybackReady(this);
         pipButton.setVisibility(show ? View.VISIBLE : View.GONE);
         if (show) {
@@ -531,7 +536,7 @@ public class ReceiverPlaybackActivity extends DrawerHostActivity {
     }
 
     private void tryEnterPictureInPicture() {
-        if (!castSessionActive) {
+        if (!castSessionActive || !AppPreferences.isReceiverPipEnabled(this)) {
             return;
         }
         if (!PermissionHelper.hasReceiverPlaybackReady(this)) {

app/src/main/java/com/foxx/androidcast/sender/DeviceListAdapter.java

@@ -18,6 +18,7 @@ import java.util.Set;
 
 /** Device list with single or multi selection. */
 public class DeviceListAdapter extends BaseAdapter {
+  private final Context context;
   private final LayoutInflater inflater;
   private final boolean multiSelect;
   private final List<DiscoveryManager.DiscoveredDevice> devices = new ArrayList<>();
@@ -25,6 +26,7 @@ public class DeviceListAdapter extends BaseAdapter {
   private final Set<Integer> selectedPositions = new LinkedHashSet<>();
 
   public DeviceListAdapter(Context context, boolean multiSelect) {
+    this.context = context;
     inflater = LayoutInflater.from(context);
     this.multiSelect = multiSelect;
   }
@@ -109,7 +111,9 @@ public class DeviceListAdapter extends BaseAdapter {
     }
     TextView label = row.findViewById(R.id.device_label);
     DiscoveryManager.DiscoveredDevice d = devices.get(position);
-    label.setText(d.name + " — " + d.host + " [" + d.transport.toUpperCase() + "]");
+    String prefix = d.pinnedRecent
+            ? context.getString(R.string.discovery_pinned_label) + " · " : "";
+    label.setText(prefix + d.name + " — " + d.host + " [" + d.transport.toUpperCase() + "]");
     boolean selected = multiSelect ? selectedPositions.contains(position) : position == selectedPosition;
     row.setActivated(selected);
     row.setSelected(selected);

app/src/main/java/com/foxx/androidcast/sender/SenderActivity.java

@@ -30,6 +30,7 @@ import com.foxx.androidcast.PermissionHelper;
 import com.foxx.androidcast.PlatformCastSupport;
 import com.foxx.androidcast.R;
 import com.foxx.androidcast.discovery.DiscoveryManager;
+import com.foxx.androidcast.discovery.PinnedReceiversStore;
 import com.foxx.androidcast.discovery.ReceiverCompatibility;
 import com.google.android.material.switchmaterial.SwitchMaterial;
 
@@ -57,6 +58,7 @@ public class SenderActivity extends DrawerHostActivity {
 
     private DiscoveryPhase discoveryPhase = DiscoveryPhase.IDLE;
     private int discoverySecondsLeft;
+    private boolean lastScanBurst;
     private final Runnable autoScanRunnable = () -> beginScanPass(false);
 
     private String pendingPin;
@@ -148,7 +150,9 @@ public class SenderActivity extends DrawerHostActivity {
             @Override
             public void onScanStarted() {
                 discoveryPhase = DiscoveryPhase.SCANNING;
-                discoverySecondsLeft = (int) (CastConfig.DISCOVERY_SCAN_PASS_MS / 1000);
+                long passMs = lastScanBurst
+                        ? CastConfig.DISCOVERY_BURST_MS : CastConfig.DISCOVERY_SCAN_PASS_MS;
+                discoverySecondsLeft = Math.max(1, (int) (passMs / 1000));
                 discoveryProgress.setVisibility(View.VISIBLE);
             }
 
@@ -209,12 +213,26 @@ public class SenderActivity extends DrawerHostActivity {
         if (deviceAdapter == null) {
             return;
         }
-        java.util.List<DiscoveryManager.DiscoveredDevice> compatible = new java.util.ArrayList<>();
-        for (DiscoveryManager.DiscoveredDevice d : lastDiscovered) {
+        java.util.LinkedHashMap<String, DiscoveryManager.DiscoveredDevice> merged =
+                new java.util.LinkedHashMap<>();
+        for (DiscoveryManager.DiscoveredDevice d : PinnedReceiversStore.load(this)) {
             if (ReceiverCompatibility.isCompatible(d, castSettings)) {
-                compatible.add(d);
+                merged.put(d.host + ":" + d.port, d);
             }
         }
+        for (DiscoveryManager.DiscoveredDevice d : lastDiscovered) {
+            if (!ReceiverCompatibility.isCompatible(d, castSettings)) {
+                continue;
+            }
+            String key = d.host + ":" + d.port;
+            DiscoveryManager.DiscoveredDevice prev = merged.get(key);
+            if (prev != null && prev.pinnedRecent) {
+                d.pinnedRecent = true;
+            }
+            merged.put(key, d);
+        }
+        java.util.List<DiscoveryManager.DiscoveredDevice> compatible =
+                new java.util.ArrayList<>(merged.values());
         deviceAdapter.setDevices(compatible);
         if (statusText == null) {
             return;
@@ -297,7 +315,8 @@ public class SenderActivity extends DrawerHostActivity {
                 discovery.clearDevices();
             }
         }
-        discovery.startBrowsing();
+        lastScanBurst = userInitiated;
+        discovery.startBrowsing(userInitiated);
     }
 
     private void startCastFlow() {
@@ -341,6 +360,7 @@ public class SenderActivity extends DrawerHostActivity {
                 Toast.makeText(this, R.string.transport_mismatch, Toast.LENGTH_LONG).show();
                 return;
             }
+            PinnedReceiversStore.recordSuccess(this, d);
             pendingTargets.add(new CastReceiverTarget(d.name, d.host, d.port, d.transport,
                     d.videoCodecs, d.audioCodecs, d.placeholderId));
         }

app/src/main/java/com/foxx/androidcast/stats/SessionStatsRecorder.java

@@ -8,6 +8,7 @@ import com.foxx.androidcast.network.control.NetworkStatsSnapshot;
 import com.foxx.androidcast.network.transport.StreamProtectionMode;
 import com.foxx.androidcast.network.transport.TransportLossStats;
 
+import org.json.JSONArray;
 import org.json.JSONObject;
 
 /**
@@ -36,6 +37,8 @@ public final class SessionStatsRecorder {
     private int fpsSamples;
 
     private final TransportLossStats lossTotals = new TransportLossStats();
+    private final JSONArray samples = new JSONArray();
+    private long lastSampleMs;
 
     public SessionStatsRecorder(String role, String transport) {
         this.role = role;
@@ -82,6 +85,7 @@ public final class SessionStatsRecorder {
         if (s == null) {
             return;
         }
+        appendTimeSample(s);
         if (s.rttMs > 0) {
             sumRttMs += s.rttMs;
         }
@@ -130,6 +134,39 @@ public final class SessionStatsRecorder {
         }
     }
 
+    private void appendTimeSample(NetworkStatsSnapshot s) {
+        long now = System.currentTimeMillis();
+        if (now - lastSampleMs < 2000L) {
+            return;
+        }
+        lastSampleMs = now;
+        try {
+            JSONObject pt = new JSONObject();
+            pt.put("t_ms", now - startedMs);
+            if (s.rttMs > 0) {
+                pt.put("rtt_ms", s.rttMs);
+            }
+            if (s.lossRatio > 0) {
+                pt.put("loss_ratio", s.lossRatio);
+            }
+            int videoKbps = s.sendBitrateKbps > 0 ? s.sendBitrateKbps : s.recvBitrateKbps;
+            if (videoKbps > 0) {
+                pt.put("video_bitrate_kbps", videoKbps);
+            }
+            if (s.encodeFps > 0) {
+                pt.put("encode_fps", s.encodeFps);
+            }
+            if (s.targetBitrateKbps > 0) {
+                pt.put("target_bitrate_kbps", s.targetBitrateKbps);
+            }
+            if (s.congestionLevel > 0) {
+                pt.put("congestion_level", s.congestionLevel);
+            }
+            samples.put(pt);
+        } catch (Exception ignored) {
+        }
+    }
+
     public void mergeSettings(CastSettings settings) {
         if (settings == null) {
             return;
@@ -209,6 +246,9 @@ public final class SessionStatsRecorder {
                 udp.put("recv_damaged_video_frames", lossTotals.recvDamagedVideoFrames);
             }
             root.put("udp", udp);
+            if (samples.length() > 0) {
+                root.put("samples", samples);
+            }
 
             SessionStatsStore.saveSession(context, startedMs, root);
         } catch (Exception ignored) {

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

@@ -218,6 +218,19 @@
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content" />
 
+            <CheckBox
+                android:id="@+id/check_receiver_pip"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="8dp"
+                android:text="@string/label_receiver_pip" />
+
+            <TextView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/receiver_pip_hint"
+                android:textSize="12sp" />
+
             <TextView
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"

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

@@ -195,10 +195,13 @@
     <string name="codec_speex">Speex</string>
     <string name="codec_opus">Opus</string>
     <string name="codec_audio_auto">AUTO (AAC)</string>
-    <string name="pip_enter">Картинка в картинке</string>
-    <string name="pip_unavailable">Режим «картинка в картинке» недоступен на этом устройстве</string>
-    <string name="pip_disabled_title">Картинка в картинке отключена</string>
-    <string name="pip_disabled_message">Разрешите картинку в картинке для Android Cast в настройках системы.</string>
+    <string name="pip_enter">Картинка в картинке (PiP)</string>
+    <string name="pip_unavailable">Режим «картинка в картинке» (PiP) недоступен на этом устройстве</string>
+    <string name="pip_disabled_title">PiP отключено</string>
+    <string name="pip_disabled_message">Разрешите PiP для Android Cast в настройках системы.</string>
     <string name="pip_permissions_hint">Уведомления нужны, чтобы приёмник оставался активным при трансляции в фоне.</string>
     <string name="permission_notifications_cast">Уведомления (статус трансляции)</string>
+    <string name="label_receiver_pip">PiP (приёмник)</string>
+    <string name="receiver_pip_hint">При включении приёмник может свернуться в плавающее окно во время трансляции (нужны уведомления). Выключено, если PiP недоступен.</string>
+    <string name="discovery_pinned_label">Недавние</string>
 </resources>

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

@@ -201,4 +201,7 @@
     <string name="pip_disabled_message">Allow picture-in-picture for Android Cast in system settings, then try again.</string>
     <string name="pip_permissions_hint">Notifications keep the receiver visible while casting in the background.</string>
     <string name="permission_notifications_cast">Notifications (cast status)</string>
+    <string name="label_receiver_pip">Enable picture-in-picture (receiver)</string>
+    <string name="receiver_pip_hint">When on, the receiver can shrink to a floating window during cast (after notifications are allowed). Off by default if PiP is unavailable.</string>
+    <string name="discovery_pinned_label">Recent</string>
 </resources>

settings.gradle

@@ -18,3 +18,5 @@ dependencyResolutionManagement {
 
 rootProject.name = "AndroidCast"
 include ':app'
+include ':session-studio'
+project(':session-studio').projectDir = file('desktop/session-studio')