Offline region feature

.gitignore

@@ -111,4 +111,4 @@ app.*.symbols
 !**/ios/**/default.pbxuser
 !**/ios/**/default.perspectivev3
 !/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages
-!/dev/ci/**/Gemfile.lock
+!/dev/ci/**/Gemfile.lock

README.md

@@ -73,6 +73,41 @@ Support for offline maps is available by *"side loading"* the required map tiles
     }
 ```
 
+## Downloading Offline Regions
+
+An offline region is a defined region of a map that is available for use in conditions with limited or no network connection. Tiles for selected region, style and precision are downloaded from Mapbox using proper SDK methods and stored in application's cache. 
+
+* Beware of selecting big regions, as size might be significant. Here is an online estimator https://docs.mapbox.com/playground/offline-estimator/.
+
+* Call `downloadOfflineRegionStream` with predefined `OfflineRegion` and optionally track progress in the callback function.
+
+```      
+    final Function(DownloadRegionStatus event) onEvent = (DownloadRegionStatus status) {
+      if (status.runtimeType == Success) {
+        // ...
+      } else if (status.runtimeType == InProgress) {
+        int progress = (status as InProgress).progress.round();
+        // ...
+      } else if (status.runtimeType == Error) {
+        // ...
+      }
+    };
+
+    final OfflineRegion offlineRegion = OfflineRegion(
+      bounds: LatLngBounds(
+        northeast: LatLng(52.5050648, 13.3915634),
+        southwest: LatLng(52.4943073, 13.4055383),
+      ),
+      id: 1,
+      minZoom: 6,
+      maxZoom: 18,
+      mapStyleUrl: 'mapbox://styles/mapbox/streets-v11',
+    );
+
+    downloadOfflineRegionStream(offlineRegion, onEvent);
+```
+
+
 ## Location features
 To enable location features in an **Android** application:
 

android/build.gradle

@@ -8,7 +8,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.2.1'
+        classpath 'com.android.tools.build:gradle:3.5.0'
     }
 }
 
@@ -40,6 +40,7 @@ android {
         implementation "com.mapbox.mapboxsdk:mapbox-android-sdk:9.2.0"
         implementation "com.mapbox.mapboxsdk:mapbox-android-plugin-annotation-v9:0.9.0"
         implementation "com.mapbox.mapboxsdk:mapbox-android-plugin-localization-v9:0.12.0"
+        implementation 'com.mapbox.mapboxsdk:mapbox-android-plugin-offline-v9:0.7.0'
     }
     compileOptions {
         sourceCompatibility 1.8

android/src/main/java/com/mapbox/mapboxgl/GlobalMethodHandler.java

@@ -1,18 +1,19 @@
 package com.mapbox.mapboxgl;
 
-import android.content.Context;
 import android.util.Log;
 
+import com.google.gson.Gson;
+import com.google.gson.JsonObject;
+import com.mapbox.mapboxgl.models.OfflineRegionData;
+
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import java.nio.file.Files;
 
 import io.flutter.plugin.common.MethodCall;
 import io.flutter.plugin.common.MethodChannel;
@@ -36,6 +37,20 @@ public void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
                 installOfflineMapTiles(tilesDb);
                 result.success(null);
                 break;
+            case "downloadOfflineRegion":
+                //Get download region arguments from caller
+                Gson gson = new Gson();
+                OfflineRegionData args = gson.fromJson(methodCall.arguments.toString(), OfflineRegionData.class);
+
+                //Start downloading
+                OfflineManagerUtils.downloadRegion(args, result, registrar, gson.fromJson(methodCall.arguments.toString(), JsonObject.class).get("accessToken").getAsString());
+                break;
+            case "getListOfRegions":
+                OfflineManagerUtils.regionsList(result, registrar.context(), new Gson().fromJson(methodCall.arguments.toString(), JsonObject.class).get("accessToken").getAsString());
+                break;
+            case "deleteOfflineRegion":
+                OfflineManagerUtils.deleteRegion(result, registrar.context(), (int) methodCall.argument("id"), new Gson().fromJson(methodCall.arguments.toString(), JsonObject.class).get("accessToken").getAsString());
+                break;
             default:
                 result.notImplemented();
                 break;
@@ -61,6 +76,14 @@ private InputStream openTilesDbFile(String tilesDb) throws IOException {
         }
     }
 
+    private String extractAccessToken(MethodCall methodCall, String fallbackValue) {
+        if (methodCall.hasArgument("accessToken")) {
+            return methodCall.argument("accessToken");
+        }
+
+        return fallbackValue;
+    }
+
     private static int copy(InputStream input, OutputStream output) throws IOException {
         final byte[] buffer = new byte[BUFFER_SIZE];
         final BufferedInputStream in = new BufferedInputStream(input, BUFFER_SIZE);

android/src/main/java/com/mapbox/mapboxgl/MapBoxUtils.java

@@ -0,0 +1,37 @@
+package com.mapbox.mapboxgl;
+
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
+import android.os.Bundle;
+import android.util.Log;
+
+import androidx.annotation.NonNull;
+
+import com.mapbox.mapboxsdk.Mapbox;
+
+abstract class MapBoxUtils {
+    private static final String TAG = "MapboxMapController";
+
+    static Mapbox getMapbox(Context context, String accessToken) {
+        return Mapbox.getInstance(context, accessToken == null ? getAccessToken(context) : accessToken);
+    }
+
+    private static String getAccessToken(@NonNull Context context) {
+        try {
+            ApplicationInfo ai = context.getPackageManager()
+                    .getApplicationInfo(context.getPackageName(), PackageManager.GET_META_DATA);
+            Bundle bundle = ai.metaData;
+            String token = bundle.getString("com.mapbox.token");
+            if (token == null || token.isEmpty()) {
+                throw new NullPointerException();
+            }
+            return token;
+        } catch (Exception e) {
+            Log.e(TAG, "Failed to find an Access Token in the Application meta-data. Maps may not load correctly. " +
+                    "Please refer to the installation guide at https://github.com/tobrun/flutter-mapbox-gl#mapbox-access-token " +
+                    "for troubleshooting advice." + e.getMessage());
+        }
+        return null;
+    }
+}

android/src/main/java/com/mapbox/mapboxgl/MapboxMapController.java

@@ -8,7 +8,6 @@
 import android.app.Activity;
 import android.app.Application;
 import android.content.Context;
-import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 import android.content.res.AssetFileDescriptor;
 import android.content.res.AssetManager;
@@ -150,7 +149,7 @@ final class MapboxMapController
     MapboxMapOptions options,
     String accessToken,
     String styleStringInitial) {
-    Mapbox.getInstance(context, accessToken!=null ? accessToken : getAccessToken(context));
+    MapBoxUtils.getMapbox(context, accessToken);
     this.id = id;
     this.context = context;
     this.activityState = activityState;
@@ -168,23 +167,6 @@ final class MapboxMapController
     this.registrarActivityHashCode = registrar.activity().hashCode();
   }
 
-  private static String getAccessToken(@NonNull Context context) {
-    try {
-      ApplicationInfo ai = context.getPackageManager().getApplicationInfo(context.getPackageName(), PackageManager.GET_META_DATA);
-      Bundle bundle = ai.metaData;
-      String token = bundle.getString("com.mapbox.token");
-      if (token == null || token.isEmpty()) {
-        throw new NullPointerException();
-      }
-      return token;
-    } catch (Exception e) {
-      Log.e(TAG, "Failed to find an Access Token in the Application meta-data. Maps may not load correctly. " +
-        "Please refer to the installation guide at https://github.com/tobrun/flutter-mapbox-gl#mapbox-access-token " +
-        "for troubleshooting advice." + e.getMessage());
-    }
-    return null;
-  }
-
   @Override
   public View getView() {
     return mapView;
@@ -1351,4 +1333,4 @@ public void onFinish() {
     public void onCancel() {
     }
   }
-}
+}

android/src/main/java/com/mapbox/mapboxgl/OfflineChannelHandlerImpl.java

@@ -0,0 +1,58 @@
+package com.mapbox.mapboxgl;
+
+import androidx.annotation.Nullable;
+
+import com.google.gson.Gson;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import io.flutter.plugin.common.BinaryMessenger;
+import io.flutter.plugin.common.EventChannel;
+
+public class OfflineChannelHandlerImpl implements EventChannel.StreamHandler {
+    private EventChannel.EventSink sink;
+    private Gson gson = new Gson();
+
+    OfflineChannelHandlerImpl(BinaryMessenger messenger, String channelName) {
+        EventChannel eventChannel = new EventChannel(messenger, channelName);
+        eventChannel.setStreamHandler(this);
+    }
+
+    @Override
+    public void onListen(Object arguments, EventChannel.EventSink events) {
+        sink = events;
+    }
+
+    @Override
+    public void onCancel(Object arguments) {
+        sink = null;
+    }
+
+    void onError(String errorCode, @Nullable String errorMessage, @Nullable Object errorDetails) {
+        if (sink == null) return;
+        sink.error(errorCode, errorMessage, errorDetails);
+    }
+
+    void onSuccess() {
+        if (sink == null) return;
+        Map<String, Object> body = new HashMap<>();
+        body.put("status", "success");
+        sink.success(gson.toJson(body));
+    }
+
+    void onStart() {
+        if (sink == null) return;
+        Map<String, Object> body = new HashMap<>();
+        body.put("status", "start");
+        sink.success(gson.toJson(body));
+    }
+
+    void onProgress(double progress) {
+        if (sink == null) return;
+        Map<String, Object> body = new HashMap<>();
+        body.put("status", "progress");
+        body.put("progress", progress);
+        sink.success(gson.toJson(body));
+    }
+}