/*
* Copyright (C) 2018 Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.wifirttscan;
import android.Manifest.permission;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.wifi.ScanResult;
import android.net.wifi.rtt.RangingRequest;
import android.net.wifi.rtt.RangingResult;
import android.net.wifi.rtt.RangingResultCallback;
import android.net.wifi.rtt.WifiRttManager;
import android.os.Bundle;
import android.os.Handler;
import androidx.annotation.NonNull;
import androidx.core.app.ActivityCompat;
import androidx.appcompat.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.List;
/**
* Displays ranging information about a particular access point chosen by the user. Uses {@link
* Handler} to trigger new requests based on
*/
public class AccessPointRangingResultsActivity extends AppCompatActivity {
private static final String TAG = "APRRActivity";
public static final String SCAN_RESULT_EXTRA =
"com.example.android.wifirttscan.extra.SCAN_RESULT";
private static final int SAMPLE_SIZE_DEFAULT = 50;
private static final int MILLISECONDS_DELAY_BEFORE_NEW_RANGING_REQUEST_DEFAULT = 1000;
// UI Elements.
private TextView mSsidTextView;
private TextView mBssidTextView;
private TextView mRangeTextView;
private TextView mRangeMeanTextView;
private TextView mRangeSDTextView;
private TextView mRangeSDMeanTextView;
private TextView mRssiTextView;
private TextView mSuccessesInBurstTextView;
private TextView mSuccessRatioTextView;
private TextView mNumberOfRequestsTextView;
private EditText mSampleSizeEditText;
private EditText mMillisecondsDelayBeforeNewRangingRequestEditText;
// Non UI variables.
private ScanResult mScanResult;
private String mMAC;
private int mNumberOfRangeRequests;
private int mNumberOfSuccessfulRangeRequests;
private int mMillisecondsDelayBeforeNewRangingRequest;
// Max sample size to calculate average for
// 1. Distance to device (getDistanceMm) over time
// 2. Standard deviation of the measured distance to the device (getDistanceStdDevMm) over time
// Note: A RangeRequest result already consists of the average of 7 readings from a burst,
// so the average in (1) is the average of these averages.
private int mSampleSize;
// Used to loop over a list of distances to calculate averages (ensures data structure never
// get larger than sample size).
private int mStatisticRangeHistoryEndIndex;
private ArrayList<Integer> mStatisticRangeHistory;
// Used to loop over a list of the standard deviation of the measured distance to calculate
// averages (ensures data structure never get larger than sample size).
private int mStatisticRangeSDHistoryEndIndex;
private ArrayList<Integer> mStatisticRangeSDHistory;
private WifiRttManager mWifiRttManager;
private RttRangingResultCallback mRttRangingResultCallback;
// Triggers additional RangingRequests with delay (mMillisecondsDelayBeforeNewRangingRequest).
final Handler mRangeRequestDelayHandler = new Handler();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_access_point_ranging_results);
// Initializes UI elements.
mSsidTextView = findViewById(R.id.ssid);
mBssidTextView = findViewById(R.id.bssid);
mRangeTextView = findViewById(R.id.range_value);
mRangeMeanTextView = findViewById(R.id.range_mean_value);
mRangeSDTextView = findViewById(R.id.range_sd_value);
mRangeSDMeanTextView = findViewById(R.id.range_sd_mean_value);
mRssiTextView = findViewById(R.id.rssi_value);
mSuccessesInBurstTextView = findViewById(R.id.successes_in_burst_value);
mSuccessRatioTextView = findViewById(R.id.success_ratio_value);
mNumberOfRequestsTextView = findViewById(R.id.number_of_requests_value);
mSampleSizeEditText = findViewById(R.id.stats_window_size_edit_value);
mSampleSizeEditText.setText(SAMPLE_SIZE_DEFAULT + "");
mMillisecondsDelayBeforeNewRangingRequestEditText =
findViewById(R.id.ranging_period_edit_value);
mMillisecondsDelayBeforeNewRangingRequestEditText.setText(
MILLISECONDS_DELAY_BEFORE_NEW_RANGING_REQUEST_DEFAULT + "");
// Retrieve ScanResult from Intent.
Intent intent = getIntent();
mScanResult = intent.getParcelableExtra(SCAN_RESULT_EXTRA);
if (mScanResult == null) {
finish();
}
mMAC = mScanResult.BSSID;
mSsidTextView.setText(mScanResult.SSID);
mBssidTextView.setText(mScanResult.BSSID);
mWifiRttManager = (WifiRttManager) getSystemService(Context.WIFI_RTT_RANGING_SERVICE);
mRttRangingResultCallback = new RttRangingResultCallback();
// Used to store range (distance) and rangeSd (standard deviation of the measured distance)
// history to calculate averages.
mStatisticRangeHistory = new ArrayList<>();
mStatisticRangeSDHistory = new ArrayList<>();
resetData();
startRangingRequest();
}
private void resetData() {
mSampleSize = Integer.parseInt(mSampleSizeEditText.getText().toString());
mMillisecondsDelayBeforeNewRangingRequest =
Integer.parseInt(
mMillisecondsDelayBeforeNewRangingRequestEditText.getText().toString());
mNumberOfSuccessfulRangeRequests = 0;
mNumberOfRangeRequests = 0;
mStatisticRangeHistoryEndIndex = 0;
mStatisticRangeHistory.clear();
mStatisticRangeSDHistoryEndIndex = 0;
mStatisticRangeSDHistory.clear();
}
private void startRangingRequest() {
// Permission for fine location should already be granted via MainActivity (you can't get
// to this class unless you already have permission. If they get to this class, then disable
// fine location permission, we kick them back to main activity.
if (ActivityCompat.checkSelfPermission(this, permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
finish();
}
mNumberOfRangeRequests++;
RangingRequest rangingRequest =
new RangingRequest.Builder().addAccessPoint(mScanResult).build();
mWifiRttManager.startRanging(
rangingRequest, getApplication().getMainExecutor(), mRttRangingResultCallback);
}
// Calculates average distance based on stored history.
private float getDistanceMean() {
float distanceSum = 0;
for (int distance : mStatisticRangeHistory) {
distanceSum += distance;
}
return distanceSum / mStatisticRangeHistory.size();
}
// Adds distance to history. If larger than sample size value, loops back over and replaces the
// oldest distance record in the list.
private void addDistanceToHistory(int distance) {
if (mStatisticRangeHistory.size() >= mSampleSize) {
if (mStatisticRangeHistoryEndIndex >= mSampleSize) {
mStatisticRangeHistoryEndIndex = 0;
}
mStatisticRangeHistory.set(mStatisticRangeHistoryEndIndex, distance);
mStatisticRangeHistoryEndIndex++;
} else {
mStatisticRangeHistory.add(distance);
}
}
// Calculates standard deviation of the measured distance based on stored history.
private float getStandardDeviationOfDistanceMean() {
float distanceSdSum = 0;
for (int distanceSd : mStatisticRangeSDHistory) {
distanceSdSum += distanceSd;
}
return distanceSdSum / mStatisticRangeHistory.size();
}
// Adds standard deviation of the measured distance to history. If larger than sample size
// value, loops back over and replaces the oldest distance record in the list.
private void addStandardDeviationOfDistanceToHistory(int distanceSd) {
if (mStatisticRangeSDHistory.size() >= mSampleSize) {
if (mStatisticRangeSDHistoryEndIndex >= mSampleSize) {
mStatisticRangeSDHistoryEndIndex = 0;
}
mStatisticRangeSDHistory.set(mStatisticRangeSDHistoryEndIndex, distanceSd);
mStatisticRangeSDHistoryEndIndex++;
} else {
mStatisticRangeSDHistory.add(distanceSd);
}
}
public void onResetButtonClick(View view) {
resetData();
}
// Class that handles callbacks for all RangingRequests and issues new RangingRequests.
private class RttRangingResultCallback extends RangingResultCallback {
private void queueNextRangingRequest() {
mRangeRequestDelayHandler.postDelayed(
new Runnable() {
@Override
public void run() {
startRangingRequest();
}
},
mMillisecondsDelayBeforeNewRangingRequest);
}
@Override
public void onRangingFailure(int code) {
Log.d(TAG, "onRangingFailure() code: " + code);
queueNextRangingRequest();
}
@Override
public void onRangingResults(@NonNull List<RangingResult> list) {
Log.d(TAG, "onRangingResults(): " + list);
// Because we are only requesting RangingResult for one access point (not multiple
// access points), this will only ever be one. (Use loops when requesting RangingResults
// for multiple access points.)
if (list.size() == 1) {
RangingResult rangingResult = list.get(0);
if (mMAC.equals(rangingResult.getMacAddress().toString())) {
if (rangingResult.getStatus() == RangingResult.STATUS_SUCCESS) {
mNumberOfSuccessfulRangeRequests++;
mRangeTextView.setText((rangingResult.getDistanceMm() / 1000f) + "");
addDistanceToHistory(rangingResult.getDistanceMm());
mRangeMeanTextView.setText((getDistanceMean() / 1000f) + "");
mRangeSDTextView.setText(
(rangingResult.getDistanceStdDevMm() / 1000f) + "");
addStandardDeviationOfDistanceToHistory(
rangingResult.getDistanceStdDevMm());
mRangeSDMeanTextView.setText(
(getStandardDeviationOfDistanceMean() / 1000f) + "");
mRssiTextView.setText(rangingResult.getRssi() + "");
mSuccessesInBurstTextView.setText(
rangingResult.getNumSuccessfulMeasurements()
+ "/"
+ rangingResult.getNumAttemptedMeasurements());
float successRatio =
((float) mNumberOfSuccessfulRangeRequests
/ (float) mNumberOfRangeRequests)
* 100;
mSuccessRatioTextView.setText(successRatio + "%");
mNumberOfRequestsTextView.setText(mNumberOfRangeRequests + "");
} else if (rangingResult.getStatus()
== RangingResult.STATUS_RESPONDER_DOES_NOT_SUPPORT_IEEE80211MC) {
Log.d(TAG, "RangingResult failed (AP doesn't support IEEE80211 MC.");
} else {
Log.d(TAG, "RangingResult failed.");
}
} else {
Toast.makeText(
getApplicationContext(),
R.string
.mac_mismatch_message_activity_access_point_ranging_results,
Toast.LENGTH_LONG)
.show();
}
}
queueNextRangingRequest();
}
}
}
