java - 在 Android 运行时请求位置权限

Question

我有一个非常简单的应用程序，它从 Google 的融合位置提供商 API 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。下面是我的 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，上述代码存在两个问题。 首先如果用户确实授予位置权限，则不会发生任何事情。不显示位置数据。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()函数在显示应用程序的设置后立即运行，我会收到消息“抱歉，我的应用程序已停止” 、'确定'、'取消'。无论我按哪个按钮，我都会保留应用程序的设置，如果我更改设置并按后退按钮，它也会关闭。

Answer 1

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...

            }

并添加此监听器以监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

                }
    }