Nghe sự kiện điều hướng

Hiện/ẩn mã Java cho hoạt động điều hướng.

package com.example.navsdkmultidestination;

import android.content.pm.PackageManager;
import android.os.Bundle;
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.Toast;
import androidx.annotation.NonNull;
import com.google.android.libraries.navigation.ArrivalEvent;
import com.google.android.libraries.navigation.Camera;
import com.google.android.libraries.navigation.ListenableResultFuture;
import com.google.android.libraries.navigation.LocationEvent;
import com.google.android.libraries.navigation.NavigationApi;
import com.google.android.libraries.navigation.Navigator;
import com.google.android.libraries.navigation.RoadSnappedLocationProvider;
import com.google.android.libraries.navigation.SimulationOptions;
import com.google.android.libraries.navigation.SupportNavigationFragment;
import com.google.android.libraries.navigation.TimeAndDistance;
import com.google.android.libraries.navigation.Waypoint;
import java.util.ArrayList;
import java.util.List;

/**
 * An activity that displays a map and a navigation UI, guiding the user
 * from their current location to multiple destinations, also known as waypoints.
 */
public class NavigationActivityMultiDestination extends AppCompatActivity {

    private static final String TAG = NavigationActivityMultiDestination.class.getSimpleName();
    private static final String DISPLAY_BOTH = "both";
    private static final String DISPLAY_TOAST = "toast";
    private static final String DISPLAY_LOG = "log";

    private Navigator mNavigator;
    private RoadSnappedLocationProvider mRoadSnappedLocationProvider;
    private SupportNavigationFragment mNavFragment;
    private final List<Waypoint> mWaypoints = new ArrayList<>();

    private Navigator.ArrivalListener mArrivalListener;
    private Navigator.RouteChangedListener mRouteChangedListener;
    private Navigator.RemainingTimeOrDistanceChangedListener
        mRemainingTimeOrDistanceChangedListener;
    private RoadSnappedLocationProvider.LocationListener mLocationListener;

    private Bundle mSavedInstanceState;
    private static final String KEY_JOURNEY_IN_PROGRESS = "journey_in_progress";
    private boolean mJourneyInProgress = false;

    // Set fields for requesting location permission.
    private static final int PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION = 1;
    private boolean mLocationPermissionGranted;

    /**
     * Sets up the navigator when the activity is created.
     * @param savedInstanceState The activity state bundle.
     */
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Save the navigator state, used to determine whether a journey is in progress.
        mSavedInstanceState = savedInstanceState;
        if (mSavedInstanceState != null
                && mSavedInstanceState.containsKey(KEY_JOURNEY_IN_PROGRESS)) {
            mJourneyInProgress = (mSavedInstanceState.getInt(KEY_JOURNEY_IN_PROGRESS) != 0);
        }

        setContentView(R.layout.activity_main);

        // Initialize the Navigation SDK.
        initializeNavigationSdk();
    }

    /**
     * Releases navigation listeners when the activity is destroyed.
     */
    @Override
    protected void onDestroy() {
        super.onDestroy();

        if ((mJourneyInProgress) && (this.isFinishing())) {
            mNavigator.removeArrivalListener(mArrivalListener);
            mNavigator.removeRouteChangedListener(mRouteChangedListener);
            mNavigator.removeRemainingTimeOrDistanceChangedListener(
                mRemainingTimeOrDistanceChangedListener);
            if (mRoadSnappedLocationProvider != null) {
                mRoadSnappedLocationProvider.removeLocationListener(mLocationListener);
            }
            displayMessage("OnDestroy: Released navigation listeners.", DISPLAY_LOG);
        }
    }

    /**
     * Saves the state of the app when the activity is paused.
     */
    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        if (mJourneyInProgress) {
            outState.putInt(KEY_JOURNEY_IN_PROGRESS, 1);
        } else {
            outState.putInt(KEY_JOURNEY_IN_PROGRESS, 0);
        }
    }

    /**
     * Starts the Navigation SDK and sets the camera to follow the device's location.
     * Calls the navigateToPlaces() method when the navigator is ready.
     */
    private void initializeNavigationSdk() {
        /*
         * Request location permission, so that we can get the location of the
         * device. The result of the permission request is handled by a callback,
         * onRequestPermissionsResult.
         */
        if (ContextCompat.checkSelfPermission(this.getApplicationContext(),
                android.Manifest.permission.ACCESS_FINE_LOCATION)
                    == PackageManager.PERMISSION_GRANTED) {
            mLocationPermissionGranted = true;
        } else {
            ActivityCompat.requestPermissions(this,
                    new String[] { android.Manifest.permission.ACCESS_FINE_LOCATION },
                    PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION);
        }

        if (!mLocationPermissionGranted) {
            displayMessage("Error loading Navigation SDK: "
                    + "The user has not granted location permission.", DISPLAY_BOTH);
            return;
        }

        // Get a navigator.
        NavigationApi.getNavigator(this, new NavigationApi.NavigatorListener() {
                    /**
                     * Sets up the navigation UI when the navigator is ready for use.
                     */
                    @Override
                    public void onNavigatorReady(Navigator navigator) {
                        displayMessage("Navigator ready.", DISPLAY_BOTH);
                        mNavigator = navigator;
                        mNavFragment = (SupportNavigationFragment) getFragmentManager()
                                .findFragmentById(R.id.navigation_fragment);

                        // Set the camera to follow the device location with 'TILTED' driving view.
                        mNavFragment.getCamera().followMyLocation(Camera.Perspective.TILTED);

                        // Navigate to the specified places.
                        navigateToPlaces();
                    }

                    /**
                     * Handles errors from the Navigation SDK.
                     * @param errorCode The error code returned by the navigator.
                     */
                    @Override
                    public void onError(@NavigationApi.ErrorCode int errorCode) {
                        switch (errorCode) {
                            case NavigationApi.ErrorCode.NOT_AUTHORIZED:
                                displayMessage("Error loading Navigation SDK: Your API key is "
                                        + "invalid or not authorized to use the Navigation SDK.",
                                        DISPLAY_BOTH);
                                break;
                            case NavigationApi.ErrorCode.TERMS_NOT_ACCEPTED:
                                displayMessage("Error loading Navigation SDK: User did not accept "
                                        + "the Navigation Terms of Use.", DISPLAY_BOTH);
                                break;
                            case NavigationApi.ErrorCode.NETWORK_ERROR:
                                displayMessage("Error loading Navigation SDK: Network error.",
                                        DISPLAY_BOTH);
                                break;
                            case NavigationApi.ErrorCode.LOCATION_PERMISSION_MISSING:
                                displayMessage("Error loading Navigation SDK: Location permission "
                                        + "is missing.", DISPLAY_BOTH);
                                break;
                            default:
                                displayMessage("Error loading Navigation SDK: " + errorCode,
                                        DISPLAY_BOTH);
                        }
                    }
                });
    }

    /**
     * Requests directions from the user's current location to a list of waypoints.
     */
    private void navigateToPlaces() {

        // Set up a waypoint for each place that we want to go to.
        createWaypoint("ChIJq6qq6jauEmsRJAf7FjrKnXI", "Sydney Star");
        createWaypoint("ChIJ3S-JXmauEmsRUcIaWtf4MzE", "Sydney Opera House");
        createWaypoint("ChIJLwgLFGmuEmsRzpDhHQuyyoU", "Sydney Conservatorium of Music");

        // If this journey is already in progress, no need to restart navigation.
        // This can happen when the user rotates the device, or sends the app to the background.
        if (mSavedInstanceState != null
                && mSavedInstanceState.containsKey(KEY_JOURNEY_IN_PROGRESS)
                && mSavedInstanceState.getInt(KEY_JOURNEY_IN_PROGRESS) == 1) {
            return;
        }

        // Create a future to await the result of the asynchronous navigator task.
        ListenableResultFuture<Navigator.RouteStatus> pendingRoute =
                mNavigator.setDestinations(mWaypoints);

        // Define the action to perform when the SDK has determined the route.
        pendingRoute.setOnResultListener(
                new ListenableResultFuture.OnResultListener<Navigator.RouteStatus>() {
                    @Override
                    public void onResult(Navigator.RouteStatus code) {
                        switch (code) {
                            case OK:
                                mJourneyInProgress = true;
                                // Hide the toolbar to maximize the navigation UI.
                                if (getActionBar() != null) {
                                    getActionBar().hide();
                                }

                                // Register some listeners for navigation events.
                                registerNavigationListeners();

                                // Display the time and distance to each waypoint.
                                displayTimesAndDistances();

                                // Enable voice audio guidance (through the device speaker).
                                mNavigator.setAudioGuidance(
                                        Navigator.AudioGuidance.VOICE_ALERTS_AND_GUIDANCE);

                                // Simulate vehicle progress along the route for demo/debug builds.
                                if (BuildConfig.DEBUG) {
                                    mNavigator.getSimulator().simulateLocationsAlongExistingRoute(
                                            new SimulationOptions().speedMultiplier(5));
                                }

                                // Start turn-by-turn guidance along the current route.
                                mNavigator.startGuidance();
                                break;
                            // Handle error conditions returned by the navigator.
                            case NO_ROUTE_FOUND:
                                displayMessage("Error starting navigation: No route found.",
                                        DISPLAY_BOTH);
                                break;
                            case NETWORK_ERROR:
                                displayMessage("Error starting navigation: Network error.",
                                        DISPLAY_BOTH);
                                break;
                            case ROUTE_CANCELED:
                                displayMessage("Error starting navigation: Route canceled.",
                                        DISPLAY_BOTH);
                                break;
                            default:
                                displayMessage("Error starting navigation: "
                                        + String.valueOf(code), DISPLAY_BOTH);
                        }
                    }
                });
    }

    /**
     * Creates a waypoint from a given place ID and title.
     * @param placeId The ID of the place to be converted to a waypoint.
     * @param title A descriptive title for the waypoint.
     */
    private void createWaypoint(String placeId, String title) {
        try {
                mWaypoints.add(
                  Waypoint.builder()
                         .setPlaceIdString(placeId)
                         .setTitle(title)
                         .build()
                );
        } catch (Waypoint.UnsupportedPlaceIdException e) {
            displayMessage("Error starting navigation: Place ID is not supported: " + placeId,
                    DISPLAY_BOTH);
        }
    }

    /**
     * Displays the calculated travel time and distance to each waypoint.
     */
    private void displayTimesAndDistances() {
        List<TimeAndDistance> timesAndDistances = mNavigator.getTimeAndDistanceList();
        int leg = 1;
        String message = "You're on your way!";
        for (TimeAndDistance timeAndDistance : timesAndDistances) {
            message = message + "\nRoute leg: " + leg++
                    + ": Travel time (seconds): " + timeAndDistance.getSeconds()
                    + ". Distance (meters): " + timeAndDistance.getMeters();
        }
        displayMessage(message, DISPLAY_BOTH);
    }

    /**
     * Registers some event listeners to show a message and take other necessary steps
     * when specific navigation events occur.
     */
    private void registerNavigationListeners() {
        mArrivalListener = new Navigator.ArrivalListener() {
            @Override
            public void onArrival(ArrivalEvent arrivalEvent) {
                displayMessage("onArrival: You've arrived at a waypoint: "
                        + mNavigator.getCurrentRouteSegment().getDestinationWaypoint().getTitle(),
                        DISPLAY_BOTH);
                // Start turn-by-turn guidance for the next leg of the route.
                if (arrivalEvent.isFinalDestination()) {
                    displayMessage("onArrival: You've arrived at the final destination.",
                            DISPLAY_BOTH);
                } else {
                    mNavigator.continueToNextDestination();
                    mNavigator.startGuidance();
                }
            }
        };
        // Listens for arrival at a waypoint.
        mNavigator.addArrivalListener(mArrivalListener);

        mRouteChangedListener = new Navigator.RouteChangedListener() {
            @Override
            public void onRouteChanged() {
                displayMessage("onRouteChanged: The driver's route has changed. Current waypoint: "
                        + mNavigator.getCurrentRouteSegment().getDestinationWaypoint().getTitle(),
                        DISPLAY_LOG);
            }
        };
        // Listens for changes in the route.
        mNavigator.addRouteChangedListener(mRouteChangedListener);

        // Listens for road-snapped location updates.
        mRoadSnappedLocationProvider =
                NavigationApi.getRoadSnappedLocationProvider(getApplication());
        mLocationListener =
            new RoadSnappedLocationProvider.LocationListener() {
                        @Override
                        public void onLocationChanged(LocationEvent locationEvent) {
                            displayMessage("onLocationUpdated: Navigation engine has provided a new"
                                            + " road-snapped location: "
                                            + locationEvent.getLocation().toString(),
                                    DISPLAY_LOG);
                        }
                    };
        if (mRoadSnappedLocationProvider != null) {
            mRoadSnappedLocationProvider.addLocationListener(mLocationListener);
        } else {
            displayMessage("ERROR: Failed to get a location provider", DISPLAY_LOG);
        }

        mRemainingTimeOrDistanceChangedListener =
            new Navigator.RemainingTimeOrDistanceChangedListener() {
                    @Override
                    public void onRemainingTimeOrDistanceChanged() {
                        displayMessage("onRemainingTimeOrDistanceChanged: Time or distance estimate"
                                + " has changed.",
                                DISPLAY_LOG);
                    }
                };
        // Listens for changes in time or distance.
        mNavigator.addRemainingTimeOrDistanceChangedListener(60, 100,
                mRemainingTimeOrDistanceChangedListener);
    }

    /**
     * Handles the result of the request for location permissions.
     */
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[],
                                           @NonNull int[] grantResults) {
        mLocationPermissionGranted = false;
        switch (requestCode) {
            case PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION: {
                // If request is canceled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    mLocationPermissionGranted = true;
                }
            }
        }
    }

    /**
     * Shows a message on screen and in the log. Used when something goes wrong.
     * @param errorMessage The message to display.
     */
    private void displayMessage(String errorMessage, String displayMedium) {
        if (displayMedium.equals(DISPLAY_BOTH) || displayMedium.equals(DISPLAY_TOAST)) {
            Toast.makeText(this, errorMessage, Toast.LENGTH_LONG).show();
        }

        if (displayMedium.equals(DISPLAY_BOTH) || displayMedium.equals(DISPLAY_LOG)) {
            Log.d(TAG, errorMessage);
        }
    }
}