com.esri.arcgisruntime.generateofflinemap.MainActivity.java Source code

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Here is the source code for com.esri.arcgisruntime.generateofflinemap.MainActivity.java

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/* Copyright 2018 Esri
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.esri.arcgisruntime.generateofflinemap;

import java.io.File;

import android.Manifest;
import android.app.ProgressDialog;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.Button;
import android.widget.Toast;

import com.esri.arcgisruntime.concurrent.Job;
import com.esri.arcgisruntime.geometry.Envelope;
import com.esri.arcgisruntime.geometry.Point;
import com.esri.arcgisruntime.loadable.LoadStatus;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.view.Graphic;
import com.esri.arcgisruntime.mapping.view.GraphicsOverlay;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.portal.Portal;
import com.esri.arcgisruntime.portal.PortalItem;
import com.esri.arcgisruntime.security.AuthenticationManager;
import com.esri.arcgisruntime.security.DefaultAuthenticationChallengeHandler;
import com.esri.arcgisruntime.symbology.SimpleLineSymbol;
import com.esri.arcgisruntime.tasks.offlinemap.GenerateOfflineMapJob;
import com.esri.arcgisruntime.tasks.offlinemap.GenerateOfflineMapParameters;
import com.esri.arcgisruntime.tasks.offlinemap.GenerateOfflineMapResult;
import com.esri.arcgisruntime.tasks.offlinemap.OfflineMapTask;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = MainActivity.class.getSimpleName();

    private MapView mMapView;
    private Button mTakeMapOfflineButton;
    private GraphicsOverlay mGraphicsOverlay;
    private Graphic mDownloadArea;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // get a reference to the map view
        mMapView = findViewById(R.id.mapView);

        // access button to take the map offline and disable it until map is loaded
        mTakeMapOfflineButton = findViewById(R.id.takeMapOfflineButton);
        mTakeMapOfflineButton.setEnabled(false);

        requestWritePermission();

        // handle authentication with the portal
        AuthenticationManager.setAuthenticationChallengeHandler(new DefaultAuthenticationChallengeHandler(this));

        // create a portal item with the itemId of the web map
        Portal portal = new Portal(getString(R.string.portal_url), false);
        PortalItem portalItem = new PortalItem(portal, getString(R.string.item_id));

        // create a map with the portal item
        ArcGISMap map = new ArcGISMap(portalItem);
        map.addDoneLoadingListener(() -> {
            if (map.getLoadStatus() == LoadStatus.LOADED) {

                // enable the map offline button only after the map is loaded
                mTakeMapOfflineButton.setEnabled(true);

                // limit the map scale to the largest layer scale
                map.setMaxScale(map.getOperationalLayers().get(6).getMaxScale());
                map.setMinScale(map.getOperationalLayers().get(6).getMinScale());
            } else {
                String error = "Map failed to load: " + map.getLoadError().getMessage();
                Toast.makeText(this, error, Toast.LENGTH_LONG).show();
                Log.e(TAG, error);
            }
        });

        // set the map to the map view
        mMapView.setMap(map);

        // create a graphics overlay for the map view
        mGraphicsOverlay = new GraphicsOverlay();
        mMapView.getGraphicsOverlays().add(mGraphicsOverlay);

        // create a graphic to show a box around the extent we want to download
        mDownloadArea = new Graphic();
        mGraphicsOverlay.getGraphics().add(mDownloadArea);
        SimpleLineSymbol simpleLineSymbol = new SimpleLineSymbol(SimpleLineSymbol.Style.SOLID, Color.RED, 2);
        mDownloadArea.setSymbol(simpleLineSymbol);

        // update the download area box whenever the viewpoint changes
        mMapView.addViewpointChangedListener(viewpointChangedEvent -> {
            if (map.getLoadStatus() == LoadStatus.LOADED) {
                // upper left corner of the area to take offline
                android.graphics.Point minScreenPoint = new android.graphics.Point(200, 200);
                // lower right corner of the downloaded area
                android.graphics.Point maxScreenPoint = new android.graphics.Point(mMapView.getWidth() - 200,
                        mMapView.getHeight() - 200);
                // convert screen points to map points
                Point minPoint = mMapView.screenToLocation(minScreenPoint);
                Point maxPoint = mMapView.screenToLocation(maxScreenPoint);
                // use the points to define and return an envelope
                if (minPoint != null && maxPoint != null) {
                    Envelope envelope = new Envelope(minPoint, maxPoint);
                    mDownloadArea.setGeometry(envelope);
                }
            }
        });
    }

    /**
     * Use the generate offline map job to generate an offline map.
     */
    private void generateOfflineMap() {

        // create a progress dialog to show download progress
        ProgressDialog progressDialog = new ProgressDialog(this);
        progressDialog.setTitle("Generate Offline Map Job");
        progressDialog.setMessage("Taking map offline...");
        progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        progressDialog.setIndeterminate(false);
        progressDialog.setProgress(0);

        // when the button is clicked, start the offline map task job
        mTakeMapOfflineButton.setOnClickListener(v -> {
            progressDialog.show();

            // delete any offline map already in the cache
            String tempDirectoryPath = getCacheDir() + File.separator + "offlineMap";
            deleteDirectory(new File(tempDirectoryPath));

            // specify the extent, min scale, and max scale as parameters
            double minScale = mMapView.getMapScale();
            double maxScale = mMapView.getMap().getMaxScale();
            // minScale must always be larger than maxScale
            if (minScale <= maxScale) {
                minScale = maxScale + 1;
            }
            GenerateOfflineMapParameters generateOfflineMapParameters = new GenerateOfflineMapParameters(
                    mDownloadArea.getGeometry(), minScale, maxScale);

            // create an offline map offlineMapTask with the map
            OfflineMapTask offlineMapTask = new OfflineMapTask(mMapView.getMap());

            // create an offline map job with the download directory path and parameters and start the job
            GenerateOfflineMapJob job = offlineMapTask.generateOfflineMap(generateOfflineMapParameters,
                    tempDirectoryPath);

            // replace the current map with the result offline map when the job finishes
            job.addJobDoneListener(() -> {
                if (job.getStatus() == Job.Status.SUCCEEDED) {
                    GenerateOfflineMapResult result = job.getResult();
                    mMapView.setMap(result.getOfflineMap());
                    mGraphicsOverlay.getGraphics().clear();
                    mTakeMapOfflineButton.setEnabled(false);
                    Toast.makeText(this, "Now displaying offline map.", Toast.LENGTH_LONG).show();
                } else {
                    String error = "Error in generate offline map job: " + job.getError().getAdditionalMessage();
                    Toast.makeText(this, error, Toast.LENGTH_LONG).show();
                    Log.e(TAG, error);
                }
                progressDialog.dismiss();
            });

            // show the job's progress with the progress dialog
            job.addProgressChangedListener(() -> progressDialog.setProgress(job.getProgress()));

            // start the job
            job.start();
        });

    }

    /**
     *
     */
    private void requestWritePermission() {
        // request write permission
        String[] reqPermission = { Manifest.permission.WRITE_EXTERNAL_STORAGE };
        int requestCode = 2;
        // for API level 23+ request permission at runtime
        if (ContextCompat.checkSelfPermission(this, reqPermission[0]) == PackageManager.PERMISSION_GRANTED) {
            generateOfflineMap();
        } else {
            // request permission
            ActivityCompat.requestPermissions(this, reqPermission, requestCode);
        }
    }

    /**
     * Handle the permissions request response.
     */
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
            @NonNull int[] grantResults) {
        if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            generateOfflineMap();
            Log.d(TAG, "permission granted");
        } else {
            // report to user that permission was denied
            Toast.makeText(this, getString(R.string.offline_map_write_permission_denied), Toast.LENGTH_SHORT)
                    .show();
        }
    }

    @Override
    protected void onPause() {
        mMapView.pause();
        super.onPause();
    }

    @Override
    protected void onResume() {
        super.onResume();
        mMapView.resume();
    }

    @Override
    protected void onDestroy() {
        mMapView.dispose();
        super.onDestroy();
    }

    /**
     * Recursively deletes all files in the given directory.
     *
     * @param file to delete
     */
    private static void deleteDirectory(File file) {
        if (file.isDirectory())
            for (File subFile : file.listFiles()) {
                deleteDirectory(subFile);
            }
        if (!file.delete()) {
            Log.e(TAG, "Failed to delete file: " + file.getPath());
        }
    }
}