使用 android 查找位置
find location with android
我想在我的 phone (android) 上制作一个程序,让用户找到他的 own_ship 位置和方向,所以我使用 App Inventor 来制作一个应用程序来做到这一点。任何人都可以帮助我制作这个应用程序,因为我是 Android 编程的新手。
我不会使用 Appinventor 来构建这样的应用程序。使用nativeAndroid,通过经纬度获取对象的位置。最好的例子是 following.
不要忘记将此权限添加到清单文件:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
java class 的代码需要类似于以下内容:
public class MainActivity extends Activity implements ConnectionCallbacks,
OnConnectionFailedListener, LocationListener {
// LogCat tag
private static final String TAG = MainActivity.class.getSimpleName();
private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 1000;
private Location mLastLocation;
// Google client to interact with Google API
private GoogleApiClient mGoogleApiClient;
// boolean flag to toggle periodic location updates
private boolean mRequestingLocationUpdates = false;
private LocationRequest mLocationRequest;
// Location updates intervals in sec
private static int UPDATE_INTERVAL = 10000; // 10 sec
private static int FATEST_INTERVAL = 5000; // 5 sec
private static int DISPLACEMENT = 10; // 10 meters
// UI elements
private TextView lblLocation;
private Button btnShowLocation, btnStartLocationUpdates;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lblLocation = (TextView) findViewById(R.id.lblLocation);
btnShowLocation = (Button) findViewById(R.id.btnShowLocation);
btnStartLocationUpdates = (Button) findViewById(R.id.btnLocationUpdates);
// First we need to check availability of play services
if (checkPlayServices()) {
// Building the GoogleApi client
buildGoogleApiClient();
createLocationRequest();
}
// Show location button click listener
btnShowLocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
displayLocation();
}
});
// Toggling the periodic location updates
btnStartLocationUpdates.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
togglePeriodicLocationUpdates();
}
});
}
@Override
protected void onStart() {
super.onStart();
if (mGoogleApiClient != null) {
mGoogleApiClient.connect();
}
}
@Override
protected void onResume() {
super.onResume();
checkPlayServices();
// Resuming the periodic location updates
if (mGoogleApiClient.isConnected() && mRequestingLocationUpdates) {
startLocationUpdates();
}
}
@Override
protected void onStop() {
super.onStop();
if (mGoogleApiClient.isConnected()) {
mGoogleApiClient.disconnect();
}
}
@Override
protected void onPause() {
super.onPause();
stopLocationUpdates();
}
/**
* Method to display the location on UI
* */
private void displayLocation() {
mLastLocation = LocationServices.FusedLocationApi
.getLastLocation(mGoogleApiClient);
if (mLastLocation != null) {
double latitude = mLastLocation.getLatitude();
double longitude = mLastLocation.getLongitude();
lblLocation.setText(latitude + ", " + longitude);
} else {
lblLocation
.setText("(Couldn't get the location. Make sure location is enabled on the device)");
}
}
/**
* Method to toggle periodic location updates
* */
private void togglePeriodicLocationUpdates() {
if (!mRequestingLocationUpdates) {
// Changing the button text
btnStartLocationUpdates
.setText(getString(R.string.btn_stop_location_updates));
mRequestingLocationUpdates = true;
// Starting the location updates
startLocationUpdates();
Log.d(TAG, "Periodic location updates started!");
} else {
// Changing the button text
btnStartLocationUpdates
.setText(getString(R.string.btn_start_location_updates));
mRequestingLocationUpdates = false;
// Stopping the location updates
stopLocationUpdates();
Log.d(TAG, "Periodic location updates stopped!");
}
}
/**
* Creating google api client object
* */
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API).build();
}
/**
* Creating location request object
* */
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL);
mLocationRequest.setFastestInterval(FATEST_INTERVAL);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
mLocationRequest.setSmallestDisplacement(DISPLACEMENT);
}
/**
* Method to verify google play services on the device
* */
private boolean checkPlayServices() {
int resultCode = GooglePlayServicesUtil
.isGooglePlayServicesAvailable(this);
if (resultCode != ConnectionResult.SUCCESS) {
if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
GooglePlayServicesUtil.getErrorDialog(resultCode, this,
PLAY_SERVICES_RESOLUTION_REQUEST).show();
} else {
Toast.makeText(getApplicationContext(),
"This device is not supported.", Toast.LENGTH_LONG)
.show();
finish();
}
return false;
}
return true;
}
/**
* Starting the location updates
* */
protected void startLocationUpdates() {
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
/**
* Stopping location updates
*/
protected void stopLocationUpdates() {
LocationServices.FusedLocationApi.removeLocationUpdates(
mGoogleApiClient, this);
}
/**
* Google api callback methods
*/
@Override
public void onConnectionFailed(ConnectionResult result) {
Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = "
+ result.getErrorCode());
}
@Override
public void onConnected(Bundle arg0) {
// Once connected with google api, get the location
displayLocation();
if (mRequestingLocationUpdates) {
startLocationUpdates();
}
}
@Override
public void onConnectionSuspended(int arg0) {
mGoogleApiClient.connect();
}
@Override
public void onLocationChanged(Location location) {
// Assign the new location
mLastLocation = location;
Toast.makeText(getApplicationContext(), "Location changed!",
Toast.LENGTH_SHORT).show();
// Displaying the new location on UI
displayLocation();
}
我想在我的 phone (android) 上制作一个程序,让用户找到他的 own_ship 位置和方向,所以我使用 App Inventor 来制作一个应用程序来做到这一点。任何人都可以帮助我制作这个应用程序,因为我是 Android 编程的新手。
我不会使用 Appinventor 来构建这样的应用程序。使用nativeAndroid,通过经纬度获取对象的位置。最好的例子是 following.
不要忘记将此权限添加到清单文件:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
java class 的代码需要类似于以下内容:
public class MainActivity extends Activity implements ConnectionCallbacks,
OnConnectionFailedListener, LocationListener {
// LogCat tag
private static final String TAG = MainActivity.class.getSimpleName();
private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 1000;
private Location mLastLocation;
// Google client to interact with Google API
private GoogleApiClient mGoogleApiClient;
// boolean flag to toggle periodic location updates
private boolean mRequestingLocationUpdates = false;
private LocationRequest mLocationRequest;
// Location updates intervals in sec
private static int UPDATE_INTERVAL = 10000; // 10 sec
private static int FATEST_INTERVAL = 5000; // 5 sec
private static int DISPLACEMENT = 10; // 10 meters
// UI elements
private TextView lblLocation;
private Button btnShowLocation, btnStartLocationUpdates;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lblLocation = (TextView) findViewById(R.id.lblLocation);
btnShowLocation = (Button) findViewById(R.id.btnShowLocation);
btnStartLocationUpdates = (Button) findViewById(R.id.btnLocationUpdates);
// First we need to check availability of play services
if (checkPlayServices()) {
// Building the GoogleApi client
buildGoogleApiClient();
createLocationRequest();
}
// Show location button click listener
btnShowLocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
displayLocation();
}
});
// Toggling the periodic location updates
btnStartLocationUpdates.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
togglePeriodicLocationUpdates();
}
});
}
@Override
protected void onStart() {
super.onStart();
if (mGoogleApiClient != null) {
mGoogleApiClient.connect();
}
}
@Override
protected void onResume() {
super.onResume();
checkPlayServices();
// Resuming the periodic location updates
if (mGoogleApiClient.isConnected() && mRequestingLocationUpdates) {
startLocationUpdates();
}
}
@Override
protected void onStop() {
super.onStop();
if (mGoogleApiClient.isConnected()) {
mGoogleApiClient.disconnect();
}
}
@Override
protected void onPause() {
super.onPause();
stopLocationUpdates();
}
/**
* Method to display the location on UI
* */
private void displayLocation() {
mLastLocation = LocationServices.FusedLocationApi
.getLastLocation(mGoogleApiClient);
if (mLastLocation != null) {
double latitude = mLastLocation.getLatitude();
double longitude = mLastLocation.getLongitude();
lblLocation.setText(latitude + ", " + longitude);
} else {
lblLocation
.setText("(Couldn't get the location. Make sure location is enabled on the device)");
}
}
/**
* Method to toggle periodic location updates
* */
private void togglePeriodicLocationUpdates() {
if (!mRequestingLocationUpdates) {
// Changing the button text
btnStartLocationUpdates
.setText(getString(R.string.btn_stop_location_updates));
mRequestingLocationUpdates = true;
// Starting the location updates
startLocationUpdates();
Log.d(TAG, "Periodic location updates started!");
} else {
// Changing the button text
btnStartLocationUpdates
.setText(getString(R.string.btn_start_location_updates));
mRequestingLocationUpdates = false;
// Stopping the location updates
stopLocationUpdates();
Log.d(TAG, "Periodic location updates stopped!");
}
}
/**
* Creating google api client object
* */
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API).build();
}
/**
* Creating location request object
* */
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL);
mLocationRequest.setFastestInterval(FATEST_INTERVAL);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
mLocationRequest.setSmallestDisplacement(DISPLACEMENT);
}
/**
* Method to verify google play services on the device
* */
private boolean checkPlayServices() {
int resultCode = GooglePlayServicesUtil
.isGooglePlayServicesAvailable(this);
if (resultCode != ConnectionResult.SUCCESS) {
if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
GooglePlayServicesUtil.getErrorDialog(resultCode, this,
PLAY_SERVICES_RESOLUTION_REQUEST).show();
} else {
Toast.makeText(getApplicationContext(),
"This device is not supported.", Toast.LENGTH_LONG)
.show();
finish();
}
return false;
}
return true;
}
/**
* Starting the location updates
* */
protected void startLocationUpdates() {
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
/**
* Stopping location updates
*/
protected void stopLocationUpdates() {
LocationServices.FusedLocationApi.removeLocationUpdates(
mGoogleApiClient, this);
}
/**
* Google api callback methods
*/
@Override
public void onConnectionFailed(ConnectionResult result) {
Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = "
+ result.getErrorCode());
}
@Override
public void onConnected(Bundle arg0) {
// Once connected with google api, get the location
displayLocation();
if (mRequestingLocationUpdates) {
startLocationUpdates();
}
}
@Override
public void onConnectionSuspended(int arg0) {
mGoogleApiClient.connect();
}
@Override
public void onLocationChanged(Location location) {
// Assign the new location
mLastLocation = location;
Toast.makeText(getApplicationContext(), "Location changed!",
Toast.LENGTH_SHORT).show();
// Displaying the new location on UI
displayLocation();
}