请求位置服务 Android答案

【问题标题】：Requesting for Location Services Android请求位置服务 Android
【发布时间】：2016-09-24 14:43:17
【问题描述】：

我正在使用此代码让用户激活位置服务。我想显示用户对话框以接受以启用位置服务，然后将它们重定向到 LOCATION_SETTINGS 页面。但是如果没有用户从用户那里接受它，它就会重定向到位置设置。

if(lm==null)
    lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
try{
    gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
}catch(Exception ex){}
try{
    network_enabled = lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}catch(Exception ex){}

if(!gps_enabled && !network_enabled){
    dialog = new AlertDialog.Builder(this);
    dialog.setMessage(this.getResources().getString(R.string.gps_network_not_enabled));
    dialog.setPositiveButton(this.getResources().getString(R.string.open_location_settings), new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface paramDialogInterface, int paramInt) {
            // TODO Auto-generated method stub
            Intent myIntent = new Intent( Settings.ACTION_LOCATION_SOURCE_SETTINGS);
            startActivity(myIntent);
            //get gps
        }
    });
    dialog.setNegativeButton(this.getString(R.string.Cancel), new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface paramDialogInterface, int paramInt) {
            // TODO Auto-generated method stub
            finish();
        }
    });
    dialog.show();

}

【问题讨论】：

标签： android

【解决方案1】：

据我了解，您尝试启用该位置。

您可以显示一个对话框来启用该位置，而不是将它们重定向到 LOCATION_SETTING 页面。

一步一步的过程。

首先你需要设置一个 GoogleApiClient 并实现 GoogleApiClient CallBackMethods。

protected synchronized void buildGoogleApiClient() {
        mGoogleApiClient = new Builder(this)
                .addApi(LocationServices.API)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API).build();
        mGoogleApiClient.connect();   
}

回调方法

@Override
public void onConnected(Bundle bundle) {
    Log.d("OnConnected", "Connection successful");
    settingsrequest();
}

@Override
public void onConnectionSuspended(int i) {
    mGoogleApiClient.connect();
}

@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
    Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = " + connectionResult.getErrorCode());
}

googleapiclient 连接后，onconnected 方法将调用，settingsRequest 方法将调用。

protected static final int REQUEST_CHECK_SETTINGS = 0x1;
LocationRequest locationRequest;


public void settingsrequest() {
    locationRequest = LocationRequest.create();
    locationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
    locationRequest.setInterval(30 * 1000);
    locationRequest.setNumUpdates(1);
    locationRequest.setExpirationDuration(20000);
    locationRequest.setFastestInterval(500);
    LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(locationRequest);
    builder.setAlwaysShow(true); //this is the key ingredient
    PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());
    result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
        @Override
        public void onResult(LocationSettingsResult result) {
            final Status status = result.getStatus();
            final LocationSettingsStates state = result.getLocationSettingsStates();
            switch (status.getStatusCode()) {
                case LocationSettingsStatusCodes.SUCCESS: {
                    LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, locationRequest, this);
                }
                // All location settings are satisfied. The client can initialize location
                // requests here.
                break;
                case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                    // Location settings are not satisfied. But could be fixed by showing the user
                    // a dialog.
                    try {
                        // Show the dialog by calling startResolutionForResult(),
                        // and check the result in onActivityResult().
                        status.startResolutionForResult(MainTab.this, REQUEST_CHECK_SETTINGS);
                    } catch (IntentSender.SendIntentException e) {
                        // Ignore the error.
                    }
                    break;
                case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                    // Location settings are not satisfied. However, we have no way to fix the
                    // settings so we won't show the dialog.
                    break;
            }
        }
    });
}

status.startResolutionForResult(MainTab.this, REQUEST_CHECK_SETTINGS) 将显示一个对话框请求位置。

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    switch (requestCode) {
   // Check for the integer request code originally supplied to startResolutionForResult().
        case REQUEST_CHECK_SETTINGS:
            switch (resultCode) {
                case Activity.RESULT_OK:
                    LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, locationRequest, this);
                    break;
                case Activity.RESULT_CANCELED:
                    break;
            }
            break;
    }
}

LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, locationRequest, this) 将为已更改的位置设置监听器。

随着位置的改变，onLocationChanged 方法将被调用。

 @Override
public void onLocationChanged(Location location) {
      prevLocation  = location;
      //Do you work
}

希望对您有所帮助。

【讨论】：