Add background location disclosure

app/src/main/java/org/traccar/client/MainActivity.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,9 +24,7 @@ public class MainActivity extends AppCompatActivity {
     @Override
     protected void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        if (savedInstanceState == null) {
-            getSupportFragmentManager().beginTransaction().replace(android.R.id.content, new MainFragment()).commit();
-        }
+        setContentView(R.layout.main);
     }
 
 }

app/src/main/java/org/traccar/client/MainFragment.java

@@ -47,6 +47,8 @@ import androidx.preference.PreferenceFragmentCompat;
 import androidx.preference.PreferenceManager;
 import androidx.preference.TwoStatePreference;
 
+import com.google.android.material.snackbar.Snackbar;
+
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Random;
@@ -69,6 +71,7 @@ public class MainFragment extends PreferenceFragmentCompat implements OnSharedPr
     public static final String KEY_WAKELOCK = "wakelock";
 
     private static final int PERMISSIONS_REQUEST_LOCATION = 2;
+    private static final String KEY_DISCLOSURE_SHOWN = "disclosureShown";
 
     private SharedPreferences sharedPreferences;
 
@@ -77,6 +80,7 @@ public class MainFragment extends PreferenceFragmentCompat implements OnSharedPr
 
     @Override
     public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
+
         if (BuildConfig.HIDDEN_APP && Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
             removeLauncherIcon();
         }
@@ -191,6 +195,17 @@ public class MainFragment extends PreferenceFragmentCompat implements OnSharedPr
     public void onResume() {
         super.onResume();
         sharedPreferences.registerOnSharedPreferenceChangeListener(this);
+
+        if (!sharedPreferences.getBoolean(KEY_DISCLOSURE_SHOWN, false)) {
+            Snackbar.make(getView(), R.string.disclosure_location, Snackbar.LENGTH_INDEFINITE)
+                    .addCallback(new Snackbar.Callback() {
+                        @Override
+                        public void onDismissed(Snackbar transientBottomBar, int event) {
+                            sharedPreferences.edit().putBoolean(KEY_DISCLOSURE_SHOWN, true).apply();
+                        }
+                    })
+                    .show();
+        }
     }
 
     @Override

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

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <androidx.fragment.app.FragmentContainerView
+        android:id="@+id/fragment"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:name="org.traccar.client.MainFragment" />
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>

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

@@ -46,4 +46,5 @@
   <string name="hidden_app_name">Device Settings</string>
   <string name="hidden_alert">The app has been hidden. To open it again please dial 8722227 (TRACCAR).</string>
   <string name="error_msg_invalid_url">Please enter a valid http:// or https:// URL</string>
+  <string name="disclosure_location">This app collects location data to enable live tracking even when the app is closed or not in use.</string>
 </resources>