在异步任务 onPostExecution 之后在当前位置绘制一个标记 [英] Plot a marker on current location after async-task onPostExecution
本文介绍了在异步任务 onPostExecution 之后在当前位置绘制一个标记的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在开发一个应用程序，我在其中使用 AsyncTask 绘制标记.我正在尝试在 onPostExeution() 上为当前位置绘制标记并将我的相机移动到当前位置.我尝试了几种方法来实现这一点，但不幸的是应用程序崩溃了.所以你们能指导我在当前位置绘制标记并移动我的一旦我在 onPostExecute() 中收到位置更新，就将相机移到那个地方.
I am developing an app where I am using AsyncTask to plot a marker. I am trying to plot marker on onPostExeution() for current location and move my camera to current location.I have tried few ways to acheive this but unfortunately app crashes.So guys can you guide me to plot a marker on current location and move my camera to that place once i receive location update in onPostExecute().
这是我的代码 -
Here's my code -
MainActivity.java
MainActivity.java
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener,OnMapReadyCallback {
SupportMapFragment sMapFragment;
public GoogleMap mMap;
private HttpURLConnection urlConnection = null;
private BufferedReader reader = null;
private String forecastJsonStr = null;
private String url = "my_url";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
sMapFragment = SupportMapFragment.newInstance();
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
sMapFragment.getMapAsync(this);
android.support.v4.app.FragmentManager sFM = getSupportFragmentManager();
sFM.beginTransaction().add(R.id.Map, sMapFragment).commit();
}
//Search option
public void onMapSearch(View view) throws IOException {
//hide button when button is pressed
InputMethodManager inputManager = (InputMethodManager) getSystemService(this.INPUT_METHOD_SERVICE);
inputManager.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
//preview the entered address as an Tost in bar
EditText locationSearch = (EditText) findViewById(R.id.editText);
String location = locationSearch.getText().toString();
//this will animate camera and zoom 12.0f
mMap.animateCamera(CameraUpdateFactory.zoomTo(12.0f));
//further address search codes
List<Address> addressList = null;
//if nothing will be entered in the edit-text will not show a toast rather than crashing of thekha app
if (locationSearch.getText().toString().equals("")) {
Toast.makeText(this, "Please enter an Address", Toast.LENGTH_LONG).show();
} else {
//process of exception handling and finding location
if (location != null || !location.equals("")) {
Geocoder geocoder = new Geocoder(this);
try {
addressList = geocoder.getFromLocationName(location, 1);
} catch (IOException e) {
e.printStackTrace();
}
//if address is greater than one then these processes will happen
if (addressList.size() > 0) {
Address address = addressList.get(0);
LatLng latLng = new LatLng(address.getLatitude(), address.getLongitude());
mMap.addMarker(new MarkerOptions()
.position(latLng)
.title(location + " is Here ")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_BLUE)));
mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
Toast.makeText(this, location + " is here, Zoom In or Zoom Out to make your Thekha Visible ", Toast.LENGTH_LONG)
.show(); //popup type to show entered data
} else {
//process where entered entry will not gonna find , this will gonna a toast to show popup
Toast.makeText(this, "Entered Address Not Found", Toast.LENGTH_LONG).show();
}
}
}
}
//Async task
ProgressDialog pd = null;
private class RetriveMarkerTask extends AsyncTask<String, Void, String> {
private Context context;
public RetriveMarkerTask(Context context) {
this.context = context;
}
@Override
protected void onPreExecute() {
pd = new ProgressDialog(MainActivity.this);
pd.setTitle("Please wait ...");
pd.setMessage("Connecting to Loofre Network");
pd.setCancelable(false);
pd.show();
}
protected String doInBackground(String... markerGetUrl) {
try {
// Construct the URL for the OpenWeatherMap query
// Possible parameters are avaiable at OWM's forecast API page, at
// http://openweathermap.org/API#forecast
URL url1 = new URL(url);
// Create the request to OpenWeatherMap, and open the connection
urlConnection = (HttpURLConnection) url1.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
forecastJsonStr = buffer.toString();
} catch (IOException e) {
Log.e("PlaceholderFragment", "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
forecastJsonStr = "Error, an exception was raised.";
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e("PlaceholderFragment", "Error closing stream", e);
}
}
}
return forecastJsonStr;
}
//on post execution
protected void onPostExecute(String markers) {
Log.d("string response", markers);
Toast.makeText(MainActivity.this, "Plotting Thekha", Toast.LENGTH_LONG).show();
try {
JSONArray jsonArray = new JSONArray(markers);
for (int i = 0; i < jsonArray.length(); i++) {
//create marker of each place in the json data
JSONObject jsonObject = jsonArray.getJSONObject(i);
String placeName = jsonObject.getString("name");
String placeAddress = jsonObject.getString("address");
double latitude = jsonObject.getJSONArray("latlang").getDouble(0);
double longitude = jsonObject.getJSONArray("latlang").getDouble(1);
LatLng loc = new LatLng(latitude, longitude);
//marker size change code
int height = 150;
int width = 150;
BitmapDrawable bitmapDrawable = (BitmapDrawable) getResources().getDrawable(R.drawable.thekhaicon);
Bitmap b = bitmapDrawable.getBitmap();
Bitmap smallMarker = Bitmap.createScaledBitmap(b, width, height, false);
//marker size change code ends here
//mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(loc, 13));
mMap.addMarker(new MarkerOptions()
.icon(BitmapDescriptorFactory.fromBitmap(smallMarker))
.title(placeName)
.snippet(placeAddress)
.position(loc)
);
LatLng dwarka = new LatLng(28.570317, 77.32182);
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(dwarka, 13));
mMap.addMarker(
new MarkerOptions()
.title("Wine Beer Liquor Shop, Sector 18, Noida")
.snippet("Sector 18, Near Centre Stage Mall, Noida")
.position(dwarka));
}
pd.dismiss();
} catch (JSONException e) {
e.printStackTrace();
}
}
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_camera) {
// Handle the camera action
} else if (id == R.id.nav_gallery) {
} else if (id == R.id.nav_slideshow) {
} else if (id == R.id.nav_manage) {
} else if (id == R.id.call_us) {
Intent intent = new Intent(Intent.ACTION_CALL);
intent.setData(Uri.parse("tel:+919717001947"));
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return true;
}
startActivity(intent);
} else if (id == R.id.about_us) {
Intent intent = new Intent(this,ScrollingActivity.class);
this.startActivity(intent);
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
@Override
public void onMapReady(GoogleMap googleMap) {
Toast.makeText(this, "Connecting Server", Toast.LENGTH_LONG).show();
mMap = googleMap;
try {
RetriveMarkerTask markerTask = new RetriveMarkerTask(MainActivity.this);
markerTask.execute(url);
}catch (Exception e){
Toast.makeText(this,"Can not fetch data",Toast.LENGTH_LONG).show();
}
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission
(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
}
//tool bar and other tool related on map uiSettings
// mMap.setMyLocationEnabled(true);
mMap.getUiSettings().setZoomControlsEnabled(true);
mMap.getUiSettings().setMapToolbarEnabled(true);
mMap.getUiSettings().setMyLocationButtonEnabled(true);
}
我的 manifest.xml 文件 -
my manifest.xml file -
<!--
The ACCESS_COARSE/FINE_LOCATION permissions are not required to use
Google Maps Android API v2, but you must specify either coarse or fine
location permissions for the 'MyLocation' functionality.
-->
<uses-permission android:name="android.permission.CALL_PHONE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSWEVICES" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<application
android:name="android.support.multidex.MultiDexApplication"
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="Thekha"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar"></activity>
<!--
The API key for Google Maps-based APIs is defined as a string resource.
(See the file "res/values/google_maps_api.xml").
Note that the API key is linked to the encryption key used to sign the APK.
You need a different API key for each encryption key, including the release key that is used to
sign the APK for publishing.
You can define the keys for the debug and release targets in src/debug/ and src/release/.
-->
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="AIzaSyAma5WZ9H5yskkt3AsQwc3aeQOFCyc9aGo" />
<activity android:name=".LoginActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ScrollingActivity"
android:label="@string/title_activity_scrolling"
android:theme="@style/AppTheme.NoActionBar"></activity>
</application>
推荐答案
嘿@Kuldeep 试试这个.
Hey @Kuldeep try this out.
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener,OnMapReadyCallback {
SupportMapFragment sMapFragment;
public GoogleMap mMap;
private HttpURLConnection urlConnection = null;
private BufferedReader reader = null;
private String forecastJsonStr = null;
private String url = "my_url";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
sMapFragment = SupportMapFragment.newInstance();
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
sMapFragment.getMapAsync(this);
android.support.v4.app.FragmentManager sFM = getSupportFragmentManager();
sFM.beginTransaction().add(R.id.Map, sMapFragment).commit();
}
//Search option
public void onMapSearch(View view) throws IOException {
//hide button when button is pressed
InputMethodManager inputManager = (InputMethodManager) getSystemService(this.INPUT_METHOD_SERVICE);
inputManager.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
//preview the entered address as an Tost in bar
EditText locationSearch = (EditText) findViewById(R.id.editText);
String location = locationSearch.getText().toString();
//this will animate camera and zoom 12.0f
mMap.animateCamera(CameraUpdateFactory.zoomTo(12.0f));
//further address search codes
List<Address> addressList = null;
//if nothing will be entered in the edit-text will not show a toast rather than crashing of thekha app
if (locationSearch.getText().toString().equals("")) {
Toast.makeText(this, "Please enter an Address", Toast.LENGTH_LONG).show();
} else {
//process of exception handling and finding location
if (location != null || !location.equals("")) {
Geocoder geocoder = new Geocoder(this);
try {
addressList = geocoder.getFromLocationName(location, 1);
} catch (IOException e) {
e.printStackTrace();
}
//if address is greater than one then these processes will happen
if (addressList.size() > 0) {
Address address = addressList.get(0);
LatLng latLng = new LatLng(address.getLatitude(), address.getLongitude());
mMap.addMarker(new MarkerOptions()
.position(latLng)
.title(location + " is Here ")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_BLUE)));
mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
Toast.makeText(this, location + " is here, Zoom In or Zoom Out to make your Thekha Visible ", Toast.LENGTH_LONG)
.show(); //popup type to show entered data
} else {
//process where entered entry will not gonna find , this will gonna a toast to show popup
Toast.makeText(this, "Entered Address Not Found", Toast.LENGTH_LONG).show();
}
}
}
}
//Async task
ProgressDialog pd = null;
private class RetriveMarkerTask extends AsyncTask<String, Void, String> {
private Context context;
public RetriveMarkerTask(Context context) {
this.context = context;
}
@Override
protected void onPreExecute() {
pd = new ProgressDialog(MainActivity.this);
pd.setTitle("Please wait ...");
pd.setMessage("Connecting to Loofre Network");
pd.setCancelable(false);
pd.show();
}
protected String doInBackground(String... markerGetUrl) {
try {
// Construct the URL for the OpenWeatherMap query
// Possible parameters are avaiable at OWM's forecast API page, at
// http://openweathermap.org/API#forecast
URL url1 = new URL(url);
// Create the request to OpenWeatherMap, and open the connection
urlConnection = (HttpURLConnection) url1.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
forecastJsonStr = buffer.toString();
} catch (IOException e) {
Log.e("PlaceholderFragment", "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
forecastJsonStr = "Error, an exception was raised.";
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e("PlaceholderFragment", "Error closing stream", e);
}
}
}
return forecastJsonStr;
}
//on post execution
protected void onPostExecute(String markers) {
Log.d("string response", markers);
Toast.makeText(MainActivity.this, "Plotting Thekha", Toast.LENGTH_LONG).show();
try {
JSONArray jsonArray = new JSONArray(markers);
for (int i = 0; i < jsonArray.length(); i++) {
//create marker of each place in the json data
JSONObject jsonObject = jsonArray.getJSONObject(i);
String placeName = jsonObject.getString("name");
String placeAddress = jsonObject.getString("address");
double latitude = jsonObject.getJSONArray("latlang").getDouble(0);
double longitude = jsonObject.getJSONArray("latlang").getDouble(1);
LatLng loc = new LatLng(latitude, longitude);
//marker size change code
int height = 150;
int width = 150;
BitmapDrawable bitmapDrawable = (BitmapDrawable) getResources().getDrawable(R.drawable.thekhaicon);
Bitmap b = bitmapDrawable.getBitmap();
Bitmap smallMarker = Bitmap.createScaledBitmap(b, width, height, false);
mMap.clear();
mMap.addMarker(new MarkerOptions()
.icon(BitmapDescriptorFactory.fromBitmap(smallMarker))
.title(placeName)
.snippet(placeAddress)
.position(loc));
mMap.addMarker(new MarkerOptions()
.icon(BitmapDescriptorFactory.fromBitmap(smallMarker))
.title(placeName)
.snippet(placeAddress)
.position(new LatLng(gps.getLatitude(),gps.getLongitude())));
CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(new LatLng(gps.getLatitude(),gps.getLongitude()), 12);
map.animateCamera(cameraUpdate);
}
pd.dismiss();
} catch (JSONException e) {
e.printStackTrace();
}
}
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_camera) {
// Handle the camera action
} else if (id == R.id.nav_gallery) {
} else if (id == R.id.nav_slideshow) {
} else if (id == R.id.nav_manage) {
} else if (id == R.id.call_us) {
Intent intent = new Intent(Intent.ACTION_CALL);
intent.setData(Uri.parse("tel:+919717001947"));
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return true;
}
startActivity(intent);
} else if (id == R.id.about_us) {
Intent intent = new Intent(this,ScrollingActivity.class);
this.startActivity(intent);
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
@Override
public void onMapReady(GoogleMap googleMap) {
Toast.makeText(this, "Connecting Server", Toast.LENGTH_LONG).show();
mMap = googleMap;
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission
(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
}
//tool bar and other tool related on map uiSettings
// mMap.setMyLocationEnabled(true);
mMap.getUiSettings().setZoomControlsEnabled(true);
mMap.getUiSettings().setMapToolbarEnabled(true);
mMap.getUiSettings().setMyLocationButtonEnabled(true);
double lat=0;
double lon=0;
GPSTracker gps=new GPSTracker(MainActivity.this);
if(gps.canGetLocation())
{
lat=gps.getLatitude();
lon=gps.getLongitude();
}
try {
LatLng myloc= new LatLng(lat,lon);
mMap.addMarker(new MarkerOptions().position(myloc).title("Marker in my Locaiton"));
mMap.moveCamera(CameraUpdateFactory.newLatLng(myloc));
RetriveMarkerTask markerTask = new RetriveMarkerTask(MainActivity.this);
markerTask.execute(url);
}catch (Exception e){
Toast.makeText(this,"Can not fetch data",Toast.LENGTH_LONG).show();
}
}
这里是 GPSTracker.java 类.
Here is GPSTracker.java class.
import android.app.AlertDialog;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.provider.Settings;
import android.util.Log;
public class GPSTracker extends Service implements LocationListener {
private final Context mContext;
// flag for GPS status
boolean isGPSEnabled = false;
// flag for network status
boolean isNetworkEnabled = false;
// flag for GPS status
boolean canGetLocation = false;
Location location; // location
double latitude; // latitude
double longitude; // longitude
// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
// Declaring a Location Manager
protected LocationManager locationManager;
public GPSTracker(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// getting network status
isNetworkEnabled = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
// no network provider is enabled
} else {
this.canGetLocation = true;
// First get location from Network Provider
if (isNetworkEnabled) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null) {
// location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
// if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return location;
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
* */
public void stopUsingGPS(){
if(locationManager != null){
locationManager.removeUpdates(GPSTracker.this);
}
}
/**
* Function to get latitude
* */
public double getLatitude(){
if(location != null){
latitude = location.getLatitude();
}
// return latitude
return latitude;
}
/**
* Function to get longitude
* */
public double getLongitude(){
if(location != null){
longitude = location.getLongitude();
}
// return longitude
return longitude;
}
/**
* Function to check GPS/wifi enabled
* @return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog
* On pressing Settings button will lauch Settings Options
* */
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS is settings");
// Setting Dialog Message
alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// On pressing Settings button
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
// on pressing cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public IBinder onBind(Intent arg0) {
return null;
}
}
这篇关于在异步任务 onPostExecution 之后在当前位置绘制一个标记的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
