Show app UID and shared-UID siblings, add uid: search filter (#229)

app/src/main/java/eu/faircode/netguard/AdapterRule.java

@@ -412,16 +412,21 @@ protected FilterResults performFiltering(CharSequence query) {
                     listResult.addAll(listAll);
                 else {
                     String queryStr = query.toString().toLowerCase().trim();
+                    // Apps sharing a UID are controlled together by the VPN (#229), so let
+                    // users explicitly search for them all with a "uid:<number>" query.
+                    boolean uidOnly = queryStr.startsWith("uid:");
+                    String uidStr = uidOnly ? queryStr.substring(4).trim() : queryStr;
                     int uid;
                     try {
-                        uid = Integer.parseInt(queryStr);
+                        uid = Integer.parseInt(uidStr);
                     } catch (NumberFormatException ignore) {
                         uid = -1;
                     }
                     for (Rule rule : listAll)
-                        if (rule.uid == uid ||
-                                rule.packageName.toLowerCase().contains(queryStr) ||
-                                (rule.name != null && rule.name.toLowerCase().contains(queryStr)))
+                        if (uidOnly ? rule.uid == uid
+                                : rule.uid == uid ||
+                                        rule.packageName.toLowerCase().contains(queryStr) ||
+                                        (rule.name != null && rule.name.toLowerCase().contains(queryStr)))
                             listResult.add(rule);
                 }
 

app/src/main/java/net/kollnig/missioncontrol/DetailsActivity.java

@@ -34,6 +34,7 @@
 import android.view.MenuItem;
 import android.view.View;
 
+import android.widget.TextView;
 import android.widget.Toast;
 
 import androidx.appcompat.app.AppCompatActivity;
@@ -153,6 +154,10 @@ protected void onCreate(Bundle savedInstanceState) {
         toolbar.setTitle(getString(R.string.app_info));
         toolbar.setSubtitle(appName);
 
+        // Show the app's UID, and any other installed packages that share it (#229),
+        // since blocking rules are applied per-UID and can therefore affect siblings.
+        showUidInfo(appUid);
+
         // Apply window insets so content avoids status/navigation bars.
         // Use padding (not margin) so the AppBarLayout's colored background
         // extends behind the transparent status bar on API 35+.
@@ -182,6 +187,37 @@ protected void onCreate(Bundle savedInstanceState) {
         });
     }
 
+    /**
+     * Shows the app's UID and, if any other installed packages share it,
+     * their names. Blocking rules in TrackerControl are applied per-UID, so
+     * apps sharing a UID are controlled together (#229) — surfacing this
+     * avoids surprising users when a setting change affects siblings too.
+     *
+     * @param uid The UID of the app being shown
+     */
+    private void showUidInfo(int uid) {
+        TextView tvUid = findViewById(R.id.tvUid);
+        if (uid < 0)
+            return;
+
+        String[] packages = getPackageManager().getPackagesForUid(uid);
+        StringBuilder others = new StringBuilder();
+        if (packages != null)
+            for (String pkg : packages)
+                if (!pkg.equals(appPackageName)) {
+                    if (others.length() > 0)
+                        others.append(", ");
+                    others.append(pkg);
+                }
+
+        String text = getString(R.string.app_uid, uid);
+        if (others.length() > 0)
+            text += "\n" + getString(R.string.app_uid_shared_with, others.toString());
+
+        tvUid.setText(text);
+        tvUid.setVisibility(View.VISIBLE);
+    }
+
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.menu_details, menu);

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

@@ -25,6 +25,19 @@
             app:titleTextColor="@android:color/white"
             app:subtitleTextColor="@android:color/white" />
 
+        <TextView
+            android:id="@+id/tvUid"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="4dp"
+            android:textColor="@android:color/white"
+            android:textSize="12sp"
+            android:alpha="0.75"
+            android:visibility="gone"
+            tools:text="App ID (UID): 10123" />
+
         <com.google.android.material.tabs.TabLayout
             android:id="@+id/tabs"
             android:layout_width="match_parent"

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

@@ -636,6 +636,9 @@ Sincerely,\n\n]]></string>
     <string name="no_internet">No Internet access</string>
     <string name="bypass_vpn_error">"Cannot block Internet. App is excluded from TrackerControl."</string>
 
+    <string name="app_uid">App ID (UID): %1$d</string>
+    <string name="app_uid_shared_with">Shares app ID with: %1$s</string>
+
     <string name="back">Back</string>
 
     <string name="forever_free">Forever Free</string>