Learn to use WebSockets on Android with OkHttp

compile 'com.squareup.okhttp3:okhttp:3.6.0'
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.ssaurel.websocket.MainActivity">
<Button
android:id="@+id/start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:text="Start !"
android:layout_marginTop="40dp"
android:textSize="17sp"/>
<TextView
android:id="@+id/output"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/start"
android:layout_centerHorizontal="true"
android:textSize="16sp"
android:layout_marginTop="30dp"/>
</RelativeLayout>
private final class EchoWebSocketListener extends WebSocketListener {
private static final int NORMAL_CLOSURE_STATUS = 1000;
@Override
public void onOpen(WebSocket webSocket, Response response) {
webSocket.send("Hello, it's SSaurel !");
webSocket.send("What's up ?");
webSocket.send(ByteString.decodeHex("deadbeef"));
webSocket.close(NORMAL_CLOSURE_STATUS, "Goodbye !");
}
@Override
public void onMessage(WebSocket webSocket, String text) {
output("Receiving : " + text);
}
@Override
public void onMessage(WebSocket webSocket, ByteString bytes) {
output("Receiving bytes : " + bytes.hex());
}
@Override
public void onClosing(WebSocket webSocket, int code, String reason) {
webSocket.close(NORMAL_CLOSURE_STATUS, null);
output("Closing : " + code + " / " + reason);
}
@Override
public void onFailure(WebSocket webSocket, Throwable t, Response response) {
output("Error : " + t.getMessage());
}
}
package com.ssaurel.websocket;import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import okhttp3.WebSocket;
import okhttp3.WebSocketListener;
import okio.ByteString;
public class MainActivity extends AppCompatActivity { private Button start;
private TextView output;
private OkHttpClient client;
private final class EchoWebSocketListener extends WebSocketListener {
private static final int NORMAL_CLOSURE_STATUS = 1000;
@Override
public void onOpen(WebSocket webSocket, Response response) {
webSocket.send("Hello, it's SSaurel !");
webSocket.send("What's up ?");
webSocket.send(ByteString.decodeHex("deadbeef"));
webSocket.close(NORMAL_CLOSURE_STATUS, "Goodbye !");
}
@Override
public void onMessage(WebSocket webSocket, String text) {
output("Receiving : " + text);
}
@Override
public void onMessage(WebSocket webSocket, ByteString bytes) {
output("Receiving bytes : " + bytes.hex());
}
@Override
public void onClosing(WebSocket webSocket, int code, String reason) {
webSocket.close(NORMAL_CLOSURE_STATUS, null);
output("Closing : " + code + " / " + reason);
}
@Override
public void onFailure(WebSocket webSocket, Throwable t, Response response) {
output("Error : " + t.getMessage());
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
start = (Button) findViewById(R.id.start);
output = (TextView) findViewById(R.id.output);
client = new OkHttpClient();
start.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
start();
}
});
} private void start() {
Request request = new Request.Builder().url("ws://echo.websocket.org").build();
EchoWebSocketListener listener = new EchoWebSocketListener();
WebSocket ws = client.newWebSocket(request, listener);
client.dispatcher().executorService().shutdown();
}
private void output(final String txt) {
runOnUiThread(new Runnable() {
@Override
public void run() {
output.setText(output.getText().toString() + "\n\n" + txt);
}
});
}
}

--

--

--

Entrepreneur / Developer / Blogger / Author. In Bitcoin We Trust: https://inbitcoinwetrust.substack.com/

Love podcasts or audiobooks? Learn on the go with our new app.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Sylvain Saurel

Sylvain Saurel

Entrepreneur / Developer / Blogger / Author. In Bitcoin We Trust: https://inbitcoinwetrust.substack.com/

More from Medium

Kotlin Coroutines, putting together the pieces

Kotlin⚡️: Constructors | Erselan Khan

Kotlin Coroutines: Coroutines are NOT light weight threads.

So in love with coding: 2 Kotlin Coroutines Articles & Kobby Plugin Article & Funny Programming 💘