feat(android): OpenIPC launcher icon + expanded connection settings

android/app/src/main/java/org/openipc/camex/SettingsBottomSheet.java

@@ -16,6 +16,7 @@
 import androidx.annotation.Nullable;
 import com.google.android.material.bottomsheet.BottomSheetDialogFragment;
 import com.google.android.material.button.MaterialButton;
+import com.google.android.material.button.MaterialButtonToggleGroup;
 import com.google.android.material.switchmaterial.SwitchMaterial;
 import com.google.android.material.textfield.TextInputEditText;
 import com.google.android.material.textfield.TextInputLayout;
@@ -29,10 +30,16 @@ public class SettingsBottomSheet extends BottomSheetDialogFragment {
     private static final String PREFS = "camex";
     private static final int DEFAULT_PORT = 5800;
     private static final String DEFAULT_NAME = "android-client";
+    // camex defaults (see src/main.c)
+    private static final int DEFAULT_MTU = 1500;
+    private static final int DEFAULT_KEEPALIVE = 10;
+    private static final int DEFAULT_TIMEOUT = 20;
 
     private TextInputEditText hostInput, portInput, nameInput, pskInput;
+    private TextInputEditText mtuInput, keepaliveInput, timeoutInput;
     private TextInputLayout pskLayout;
     private SwitchMaterial encryptSwitch;
+    private MaterialButtonToggleGroup transportGroup;
 
     @Nullable
     @Override
@@ -52,6 +59,10 @@ public void onViewCreated(@NonNull View v, @Nullable Bundle savedInstanceState)
         pskInput = v.findViewById(R.id.input_psk);
         pskLayout = v.findViewById(R.id.layout_psk);
         encryptSwitch = v.findViewById(R.id.switch_encrypt);
+        transportGroup = v.findViewById(R.id.group_transport);
+        mtuInput = v.findViewById(R.id.input_mtu);
+        keepaliveInput = v.findViewById(R.id.input_keepalive);
+        timeoutInput = v.findViewById(R.id.input_server_timeout);
 
         SharedPreferences prefs = requireContext().getSharedPreferences(PREFS, 0);
         hostInput.setText(prefs.getString("server_host", ""));
@@ -64,6 +75,14 @@ public void onViewCreated(@NonNull View v, @Nullable Bundle savedInstanceState)
 
         encryptSwitch.setOnCheckedChangeListener((b, checked) -> pskLayout.setEnabled(checked));
 
+        // Transport: default UDP unless "tcp" was saved.
+        boolean tcp = "tcp".equals(prefs.getString("transport", "udp"));
+        transportGroup.check(tcp ? R.id.btn_tcp : R.id.btn_udp);
+
+        mtuInput.setText(String.valueOf(prefs.getInt("mtu", DEFAULT_MTU)));
+        keepaliveInput.setText(String.valueOf(prefs.getInt("keepalive", DEFAULT_KEEPALIVE)));
+        timeoutInput.setText(String.valueOf(prefs.getInt("server_timeout", DEFAULT_TIMEOUT)));
+
         MaterialButton save = v.findViewById(R.id.btn_save);
         save.setOnClickListener(view -> save(prefs));
     }
@@ -90,12 +109,37 @@ private void save(SharedPreferences prefs) {
         String name = text(nameInput);
         if (TextUtils.isEmpty(name)) name = DEFAULT_NAME;
 
+        int mtu = parseInt(mtuInput, DEFAULT_MTU);
+        if (mtu < 576 || mtu > 9000) {
+            mtuInput.setError(getString(R.string.err_mtu));
+            return;
+        }
+
+        int keepalive = parseInt(keepaliveInput, DEFAULT_KEEPALIVE);
+        if (keepalive < 0 || keepalive > 3600) {
+            keepaliveInput.setError(getString(R.string.err_keepalive));
+            return;
+        }
+
+        int timeout = parseInt(timeoutInput, DEFAULT_TIMEOUT);
+        if (timeout < 5 || timeout > 3600) {
+            timeoutInput.setError(getString(R.string.err_timeout));
+            return;
+        }
+
+        String transport =
+            transportGroup.getCheckedButtonId() == R.id.btn_tcp ? "tcp" : "udp";
+
         prefs.edit()
             .putString("server_host", host)
             .putInt("server_port", port)
             .putString("name", name)
+            .putString("transport", transport)
             .putBoolean("encrypt", encryptSwitch.isChecked())
             .putString("psk", text(pskInput))
+            .putInt("mtu", mtu)
+            .putInt("keepalive", keepalive)
+            .putInt("server_timeout", timeout)
             .apply();
 
         Toast.makeText(requireContext(), R.string.save, Toast.LENGTH_SHORT).show();
@@ -105,4 +149,14 @@ private void save(SharedPreferences prefs) {
     private static String text(TextInputEditText input) {
         return input.getText() == null ? "" : input.getText().toString().trim();
     }
+
+    private static int parseInt(TextInputEditText input, int fallback) {
+        String s = text(input);
+        if (TextUtils.isEmpty(s)) return fallback;
+        try {
+            return Integer.parseInt(s);
+        } catch (NumberFormatException ignored) {
+            return fallback;
+        }
+    }
 }

android/app/src/main/java/org/openipc/camex/TunnelService.java

@@ -72,6 +72,11 @@ public int onStartCommand(Intent intent, int flags, int startId) {
                 args.add("--name"); args.add(getName());
                 args.add("--server-host"); args.add(getServerHost());
                 args.add("--port"); args.add(String.valueOf(getServerPort()));
+                args.add("--transport"); args.add(getTransport());
+                args.add("--mtu"); args.add(String.valueOf(getInt("mtu", 1500)));
+                args.add("--keepalive"); args.add(String.valueOf(getInt("keepalive", 10)));
+                args.add("--server-timeout");
+                args.add(String.valueOf(getInt("server_timeout", 20)));
                 if (getEncrypt()) {
                     args.add("--encrypt");
                     String psk = getPsk();
@@ -112,6 +117,16 @@ private String getName() {
             .getString("name", "android-client");
     }
 
+    private String getTransport() {
+        // udp (default) or tcp
+        return getSharedPreferences("camex", MODE_PRIVATE)
+            .getString("transport", "udp");
+    }
+
+    private int getInt(String key, int def) {
+        return getSharedPreferences("camex", MODE_PRIVATE).getInt(key, def);
+    }
+
     private boolean getEncrypt() {
         return getSharedPreferences("camex", MODE_PRIVATE)
             .getBoolean("encrypt", false);

android/app/src/main/res/drawable/ic_launcher_background.xml

@@ -10,6 +10,6 @@
     android:viewportWidth="108"
     android:viewportHeight="108">
     <path
-        android:fillColor="#1565C0"
+        android:fillColor="#4D60D9"
         android:pathData="M0,0h108v108H0z" />
 </vector>

android/app/src/main/res/layout/bottom_sheet_settings.xml

@@ -64,11 +64,44 @@
                 android:maxLines="1" />
         </com.google.android.material.textfield.TextInputLayout>
 
+        <!-- Transport: UDP (default) / TCP -->
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="20dp"
+            android:text="@string/transport"
+            android:textSize="14sp" />
+
+        <com.google.android.material.button.MaterialButtonToggleGroup
+            android:id="@+id/group_transport"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="4dp"
+            app:singleSelection="true"
+            app:selectionRequired="true">
+
+            <com.google.android.material.button.MaterialButton
+                android:id="@+id/btn_udp"
+                style="?attr/materialButtonOutlinedStyle"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:text="@string/transport_udp" />
+
+            <com.google.android.material.button.MaterialButton
+                android:id="@+id/btn_tcp"
+                style="?attr/materialButtonOutlinedStyle"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:text="@string/transport_tcp" />
+        </com.google.android.material.button.MaterialButtonToggleGroup>
+
         <com.google.android.material.switchmaterial.SwitchMaterial
             android:id="@+id/switch_encrypt"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:layout_marginTop="16dp"
+            android:layout_marginTop="20dp"
             android:text="@string/encrypt" />
 
         <com.google.android.material.textfield.TextInputLayout
@@ -87,6 +120,57 @@
                 android:maxLines="1" />
         </com.google.android.material.textfield.TextInputLayout>
 
+        <!-- Advanced tunnel parameters -->
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="24dp"
+            android:text="@string/advanced"
+            android:textSize="16sp"
+            android:textStyle="bold" />
+
+        <com.google.android.material.textfield.TextInputLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="8dp"
+            android:hint="@string/mtu">
+
+            <com.google.android.material.textfield.TextInputEditText
+                android:id="@+id/input_mtu"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:inputType="number"
+                android:maxLines="1" />
+        </com.google.android.material.textfield.TextInputLayout>
+
+        <com.google.android.material.textfield.TextInputLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="8dp"
+            android:hint="@string/keepalive">
+
+            <com.google.android.material.textfield.TextInputEditText
+                android:id="@+id/input_keepalive"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:inputType="number"
+                android:maxLines="1" />
+        </com.google.android.material.textfield.TextInputLayout>
+
+        <com.google.android.material.textfield.TextInputLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="8dp"
+            android:hint="@string/server_timeout">
+
+            <com.google.android.material.textfield.TextInputEditText
+                android:id="@+id/input_server_timeout"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:inputType="number"
+                android:maxLines="1" />
+        </com.google.android.material.textfield.TextInputLayout>
+
         <com.google.android.material.button.MaterialButton
             android:id="@+id/btn_save"
             android:layout_width="match_parent"

android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
     <background android:drawable="@drawable/ic_launcher_background" />
-    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <foreground android:drawable="@mipmap/ic_launcher_foreground" />
 </adaptive-icon>

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

@@ -17,7 +17,26 @@
     <string name="server_host">Server host</string>
     <string name="server_port">Server port</string>
     <string name="client_name">Client name</string>
-    <string name="encrypt">Encrypt traffic</string>
+
+    <!-- Transport -->
+    <string name="transport">Transport</string>
+    <string name="transport_udp">UDP</string>
+    <string name="transport_tcp">TCP</string>
+
+    <!-- Security -->
+    <string name="encrypt">Encrypt traffic (ChaCha20-Poly1305)</string>
     <string name="psk">Pre-shared key</string>
+
+    <!-- Advanced -->
+    <string name="advanced">Advanced</string>
+    <string name="mtu">MTU (576–9000)</string>
+    <string name="keepalive">Keepalive, sec (0 = off)</string>
+    <string name="server_timeout">Server timeout, sec (5–3600)</string>
+
     <string name="save">Save</string>
+
+    <!-- Validation errors -->
+    <string name="err_mtu">MTU must be 576–9000</string>
+    <string name="err_keepalive">Keepalive must be 0–3600</string>
+    <string name="err_timeout">Timeout must be 5–3600</string>
 </resources>