我有一个非常简单的应用程序，它从Google融合的位置提供程序API中获取位置数据并显示它。现在，对于Android M +，我想在运行时请求位置权限。以下是我的MainActivity.java文件中的一些相关代码：
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if(checkAndRequestPermissions()) {
// carry on the normal flow, as the case of permissions granted.
mLatitudeTextView = (TextView) findViewById((R.id.latitude_textview));
mLongitudeTextView = (TextView) findViewById((R.id.longitude_textview));
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mLocationManager = (LocationManager)this.getSystemService(Context.LOCATION_SERVICE);
checkLocation(); //check whether location service is enable or not in your phone
}
}
private boolean checkAndRequestPermissions() {
int permissionLocation = ContextCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION);
List<String> listPermissionsNeeded = new ArrayList<>();
if (permissionLocation != PackageManager.PERMISSION_GRANTED) {
listPermissionsNeeded.add(Manifest.permission.ACCESS_FINE_LOCATION);
}
if (!listPermissionsNeeded.isEmpty()) {
ActivityCompat.requestPermissions(this, listPermissionsNeeded.toArray(new String[listPermissionsNeeded.size()]), REQUEST_ID_MULTIPLE_PERMISSIONS);
return false;
}
return true;
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
Log.d(TAG, "Permission callback called-------");
switch (requestCode) {
case REQUEST_ID_MULTIPLE_PERMISSIONS: {
Map<String, Integer> perms = new HashMap<>();
// Initialize the map with both permissions
perms.put(Manifest.permission.ACCESS_FINE_LOCATION, PackageManager.PERMISSION_GRANTED);
// Fill with actual results from user
if (grantResults.length > 0) {
for (int i = 0; i < permissions.length; i++)
perms.put(permissions[i], grantResults[i]);
// Check for both permissions
if (perms.get(Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
Log.d(TAG, "sms & location services permission granted");
// process the normal flow
mLatitudeTextView = (TextView) findViewById((R.id.latitude_textview));
mLongitudeTextView = (TextView) findViewById((R.id.longitude_textview));
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mLocationManager = (LocationManager)this.getSystemService(Context.LOCATION_SERVICE);
checkLocation(); //check whether location service is enable or not in your phone
//else any one or both the permissions are not granted
} else {
Log.d(TAG, "Some permissions are not granted ask again ");
//permission is denied (this is the first time, when "never ask again" is not checked) so ask again explaining the usage of permission
// shouldShowRequestPermissionRationale will return true
//show the dialog or snackbar saying its necessary and try again otherwise proceed with setup.
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_FINE_LOCATION)) {
showDialogOK("Service Permissions are required for this app",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
checkAndRequestPermissions();
break;
case DialogInterface.BUTTON_NEGATIVE:
// proceed with logic by disabling the related features or quit the app.
System.exit(1);
break;
}
}
});
}
//permission is denied (and never ask again is checked)
//shouldShowRequestPermissionRationale will return false
else {
explain("You need to give some mandatory permissions to continue. Do you want to go to app settings?");
// //proceed with logic by disabling the related features or quit the app.
}
}
}
}
}
}
private void showDialogOK(String message, DialogInterface.OnClickListener okListener) {
new AlertDialog.Builder(this)
.setMessage(message)
.setPositiveButton("OK", okListener)
.setNegativeButton("Cancel", okListener)
.create()
.show();
}
private void explain(String msg){
final android.support.v7.app.AlertDialog.Builder dialog = new android.support.v7.app.AlertDialog.Builder(this);
dialog.setMessage(msg)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
// permissionsclass.requestPermission(type,code);
startActivity(new Intent(android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:com.myapp.myapplication")));
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
System.exit(1);
}
});
dialog.show();
}
@Override
public void onConnected(Bundle bundle) {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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.
return;
}
startLocationUpdates();
mLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if(mLocation == null){
startLocationUpdates();
}
if (mLocation != null) {
// mLatitudeTextView.setText(String.valueOf(mLocation.getLatitude()));
//mLongitudeTextView.setText(String.valueOf(mLocation.getLongitude()));
} else {
Toast.makeText(this, "Location not Detected", Toast.LENGTH_SHORT).show();
}
}
protected void startLocationUpdates() {
// Create the location request
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(UPDATE_INTERVAL)
.setFastestInterval(FASTEST_INTERVAL);
// Request location updates
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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.
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest, this);
Log.d("reque", "--->>>>");
}
private boolean checkLocation() {
if(!isLocationEnabled())
showAlert();
return isLocationEnabled();
}
private void showAlert() {
final AlertDialog.Builder dialog = new AlertDialog.Builder(this);
dialog.setTitle("Enable Location")
.setMessage("Your Locations Settings is set to 'Off'.\nPlease Enable Location to " +
"use this app")
.setPositiveButton("Location Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
Intent myIntent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(myIntent);
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
}
});
dialog.show();
}
private boolean isLocationEnabled() {
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
return locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) ||
locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}
到目前为止，以上代码中存在两个问题。 First如果用户确实授予了位置许可，则什么也不会发生。没有显示位置数据。仅当我重新启动应用程序时，我才能看到位置数据。
第二，如果用户选中“不再询问”，并且我的explain（）函数运行，则在显示应用程序设置后立即运行，我收到消息“对不起，我的应用程序已停止”，“确定” ，'取消'。无论我按哪个按钮，我都会保留在应用程序的设置中；如果更改设置并按返回按钮，则它也会关闭。
if (ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED || ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
//Permission not Granted...
requestPermissions(
new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
Constant.RequestPermissions.LOCATIONS);
} else {
//Permission has been already Granted...
}
并添加此侦听器以侦听用户对该权限请求的操作-
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[],
@NonNull int[] grantResults) {
switch (requestCode) {
case Constant.RequestPermissions.LOCATIONS:
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED
&& grantResults[1] == PackageManager.PERMISSION_GRANTED) {
// User Allows Permission access
}
else
{
// User denies Permission access
}
}
好，您必须在两种情况下启动服务：-
1）当用户授予位置访问权限时。
2）用户启动应用程序后已经授予权限再次。
所以您必须同时处理两种方式
尝试一下。
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
public boolean checkLocationPermission() {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission. ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission. ACCESS_FINE_LOCATION)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
new AlertDialog.Builder(this)
.setTitle(R.string.title_location_permission)
.setMessage(R.string.text_location_permission)
.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
})
.create()
.show();
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission. ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
return false;
} else {
return true;
}
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// location-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission. ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
// do your stuff here
}
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
}
return;
}
}
}
OnResume()中的操作
@Override
protected void onResume() {
super.onResume();
if (checkLocationPermission()) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission. ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
// do your stuff here
}
}
}