Most of the apps today are developed and designed which can perform on all types of networks. While some of us are probably enjoying great connectivity courtesy of our carriers at our school/office/coffees shop wi-fi, there are still some people suffering from poor mobile connections, particularly in emerging markets. If you are developing an Android app you may already fetching information from internet. While doing so there is a chance that internet connection is not available on users handset, connection is slow or fast. Hence its always a good idea to create an app that can perform accordingly on all types of networks.

Facebook has made it known that their goal is to be able to reach and give access to as many markets as possible, and this includes those that still use 2G connections. In this post, we will share how this is possible by Network Connection Class. 

Network Connection Class allows you to check the quality of the internet connection of the current user, it is an android library. It is a simple code that will help you identify what kind of internet connection a user has on his/her device. Network Connection Class currently only measures the user’s downstream bandwidth. Latency is also an important factor, but in our tests, we’ve found that bandwidth is a good proxy for both.

The connection gets classified into several Connection Classes that makes it easy to develop against. The library does this by listening to the existing internet traffic done by your app and notifying you when the user’s connection quality changes. Developers can then use this Connection Class information and adjust the application’s behavior (request lower quality images or video, throttle type-ahead, etc).

The Network Connection Class library takes care of spikes using a moving average of the incoming samples, and also applies some hysteresis (both with a minimum number of samples and amount the average has to cross a boundary before triggering a bucket change):

Code Sample:
Connection Class provides an interface for classes to add themselves as listeners for when the network’s connection quality changes. In the subscriber class, implement ConnectionClassStateChangeListener:

[section_tc][column_tc span=’12’][blockquote_tc style=’style4′ class=”blog-code”]package com.example.android.connectionclasstest;

import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import com.facebook.network.connectionclass.ConnectionClassManager;
import com.facebook.network.connectionclass.ConnectionQuality;
import com.facebook.network.connectionclass.DeviceBandwidthSampler;

import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;

public class MainActivity extends AppCompatActivity {

private static final String TAG = “ConnectionClass-Sample”;
private ConnectionClassManager mConnectionClassManager;
private DeviceBandwidthSampler mDeviceBandwidthSampler;
private TextView mTextView;
private ImageView mImageView;
private ImageLoader imageLoader;
private ProgressBar mRunningBar;
private ConnectionChangedListener mListener;
private int mTries = 0;
private ConnectionQuality mConnectionClass = ConnectionQuality.UNKNOWN;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageLoader = ImageLoader.getInstance();
imageLoader.init(ImageLoaderConfiguration.createDefault(getBaseContext()));
mConnectionClassManager = ConnectionClassManager.getInstance();
mDeviceBandwidthSampler = DeviceBandwidthSampler.getInstance();
mRunningBar = (ProgressBar) findViewById(R.id.runnigBar);
mTextView = (TextView) findViewById(R.id.connectionClass);
mImageView = (ImageView) findViewById(R.id.imageView);
findViewById(R.id.testButton).setOnClickListener(DownloadImage);
mTextView.setText(mConnectionClassManager.getCurrentBandwidthQuality().toString());
mListener = new ConnectionChangedListener();
findViewById(R.id.upload).setOnClickListener(UploadImage);
findViewById(R.id.vdButton).setOnClickListener(PlayVideo);
}

@Override
protected void onPause() {
super.onPause();
mConnectionClassManager.remove(mListener);
}

@Override
protected void onResume() {
super.onResume();

mConnectionClassManager.register(mListener);
}
String connectionQuality=null;

private class ConnectionChangedListener
implements ConnectionClassManager.ConnectionClassStateChangeListener {

@Override
public void onBandwidthStateChange(ConnectionQuality bandwidthState) {
mConnectionClass = bandwidthState;
runOnUiThread(new Runnable() {
@Override
public void run() {

connectionQuality = mConnectionClass.toString();
switch (connectionQuality){
case “POOR”:
double val1 = mConnectionClassManager.getDownloadKBitsPerSecond();
mTextView.setText(“Quality is “+connectionQuality+” “+val1 +” and Bandwidth under 150 kbps so poor quality Image downloaded”);
android.support.design.widget.Snackbar.make(findViewById(R.id.main),”Quality is “+connectionQuality+ val1 +”\n and Bandwidth under 150 kbps so poor\n quality image is downloading”, android.support.design.widget.Snackbar.LENGTH_LONG).show();
new DnloadImage().execute(“http://storage.googleapis.com/ix_choosemuse/uploads/2016/02/android-logo.png”); // 80 kb
break;

case “MODERATE”:
double val2 = mConnectionClassManager.getDownloadKBitsPerSecond();
mTextView.setText(“Quality is “+connectionQuality+” “+val2 +” and Bandwidth between 150 to 550 kbps so moderate quality Image downloaded”);
android.support.design.widget.Snackbar.make(findViewById(R.id.main),”Quality is “+connectionQuality+ val2 +”\n and Bandwidth between 150 to 550 kbps so moderate\n quality Image is downloading”, android.support.design.widget.Snackbar.LENGTH_LONG).show();
new DnloadImage().execute(“http://static.giantbomb.com/uploads/original/15/157771/2312725-a10.jpeg”); // 454 kb
break;

case “GOOD”:
double val3 = mConnectionClassManager.getDownloadKBitsPerSecond();
android.support.design.widget.Snackbar.make(findViewById(R.id.main),”Quality is “+connectionQuality+ val3 +”\n and Bandwidth between 550 to 2000 kbps so good\n quality Image is downloading”, android.support.design.widget.Snackbar.LENGTH_LONG).show();
mTextView.setText(“Quality is “+connectionQuality+” “+val3 +” and Bandwidth between 550 to 2000 kbps so good quality Image downloaded”);
new DnloadImage().execute(“http://techclones.com/wp-content/uploads/2013/09/Best-Dark-HD-Wallpaper-Android1.png”); // 1.04 mb
break;

case “EXCELLENT”:
double val4 = mConnectionClassManager.getDownloadKBitsPerSecond();
mTextView.setText(“Quality is “+connectionQuality+” “+val4 +” and Bandwidth over 2000 kbps so excellent quality Image downloaded”);
android.support.design.widget.Snackbar.make(findViewById(R.id.main),”Quality is “+connectionQuality+ val4 +”\n and Bandwidth over 2000 kbps so high\n quality Image is downlaoding”, android.support.design.widget.Snackbar.LENGTH_LONG).show();
new DnloadImage().execute(“http://static.giantbomb.com/uploads/original/15/157771/2312721-a7.png”); // 2.49 mb
break;

case “UNKNOWN”:
mTextView.setText(“Sorry we are getting nothing”);
break;
}
}
});
}
}

private final View.OnClickListener DownloadImage = new View.OnClickListener() {
@Override
public void onClick(View v) {
mRunningBar.setVisibility(View.VISIBLE);
mTries=0;
String quality = mConnectionClass.toString();
Toast.makeText(MainActivity.this, “Quality ->”+quality, Toast.LENGTH_SHORT).show();
new DnloadImage().execute(“”);
}
};

private final View.OnClickListener UploadImage = new View.OnClickListener() {
@Override
public void onClick(View v) {
//showFileChooser();
Intent intent = new Intent(MainActivity.this, UplaodActivity.class);
startActivity(intent);
}
};

private final View.OnClickListener PlayVideo = new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, VideoActivity.class);
startActivity(intent);
}
};

private class DnloadImage extends AsyncTask<String, Void, Bitmap> {

@Override
protected void onPreExecute() {
mDeviceBandwidthSampler.startSampling();
mRunningBar.setVisibility(View.VISIBLE);
}

@Override
protected Bitmap doInBackground(String… url) {
String imageURL = url[0];
try {
ByteArrayInputStream byteArrayInputStream;
// Bitmap bitmap;
URLConnection connection = new URL(imageURL).openConnection();
connection.setUseCaches(false);
connection.connect();
InputStream input = connection.getInputStream();

try {
Bitmap bitmap = BitmapFactory.decodeStream(input);
return bitmap;
} finally {
input.close();
}
} catch (IOException e) {
Log.e(TAG, “Error while downloading image.”);
}
return null;
}

@Override
protected void onPostExecute(Bitmap bp) {
mDeviceBandwidthSampler.stopSampling();
Toast.makeText(MainActivity.this,””+mTries,Toast.LENGTH_SHORT).show();

if (mConnectionClass == ConnectionQuality.UNKNOWN && mTries < 10) {
mTries++;
new DnloadImage().execute(“https://familysearch.org/learn/wiki/en/images/9/9d/Links-Folder-icon.png”);
}
if (!mDeviceBandwidthSampler.isSampling()) {
mImageView.setImageBitmap(bp);
//imageLoader.getInstance().displayImage(mURL,mImageView);
mRunningBar.setVisibility(View.GONE);

}
}
}
}[/blockquote_tc][/column_tc][/section_tc]

The main way to provide the ConnectionClassManager data is to use the DeviceBandwidthSampler. The DeviceBandwidthSampler samples the device’s underlying network stats, when you tell it you’re performing some sort of network activity (downloading photos, playing a video, etc).

To know more about the Network Connection Class and its implementation, feel free to say hello@mantralabsglobal.com. We would surely respond to your queries.