Kotlin 101: How to communicate to a Bluetooth device Part 2

[@kleanlins]

I'm sorry, but how did you get that UUID?

[@ASDoublecAp]

Bro, I just wanted to say THANKS. You’re a genius and you saved my project. THANKS again :’)

[@AndreasHel197]

how can i read data from the device?

[@pauloborralho152]

perfect, it works great! Thank you for your effort and your patience to do this. I know nothing about kotlin or android studio and I think this is the best way to learn. Old cell phones can be recycled and usefull again with apps. I (as other people here) will try to send serial data from a HC06 to the cell phone and process/save it. I also liked your calm style, and your explaining everything. Great Job

[@josecastellanos4836]

Bestest example about this interaction, Thanks for your help...

[@sudhir1274]

Clear and concise tutorial. Very useful.

[@florianmoser7459]

Great tutorial! But please use a series resistor for the led.

[@rmirabelle]

You already pass Context as c in the default constructor. Just declare it as a val [val c:Context] instead of as a parameter [c:Context] and you can avoid the leaky copy of Context that you create and use [c] where needed instead of [context]

[@Tutos-ME]

It doesn´t work, could you help me? Everything´s working fine, when I clic a button in the app the arduino 'TX' led turns on, but LED connected to Pin 13 does not. Maybe is 'cause in the app you have sendCommand("a") & sendCommand("b") A&B toByteArray , and arduino expects a '1' or '0'. How can I fix this? Thanks

[@poobels]

Same Problem here. Have you been able to fix it? Nevermind. You were right. I just changed "a" and "b" to "1" and "0" in ControlActivity.kt and it worked. Ty

[@Tutos-ME]

@@poobels you could also change Arduino file to expect A and B

[@carlosproduction4183]

Hi, thank you again ! I have "Unresolved SelectDeviceActivity" ! Do you have an idea ?

[@KiroLive]

I have the same issue, did you fix it?

[@carlosproduction4183]

@@KiroLive No, I didn't ! I try to mail the video creator but they seems to be dead (or, at least, out of the game) !

[@sepldepl4540]

I think he renamed the MainActivity to SelectDeviceActivity or somethig so u just need to switch SelectDeviceActivity to MainActivity (tahts what i did)

[@ballaownz]

Same here, any ideas?

[@the-fantabulous-g]

@@ballaownz It's what sepldepl said; we change the line where we define class for MainActivity.kt (or SelectDeviceActivity.kt, if you renamed the file but not the classname) from: class MainActivity : AppCompatActivity() { to: class SelectDeviceActivity : AppCompatActivity() { This solved my issue here

[@iamrobert505]

Where did you get the UUID from? does it work with any device? you didn't explain that part

[@Morphinwithyou]

Dude you're awesome. Thanks!

[@marcocastaneda2385]

Where do I get the UUID?

[@dork3nergy]

Great tutorial. Works like a charm. Thanks!

[@antonyhelsby9374]

I copied your code exactly and when I run the app with the bluetooth module running on the arduino, it says no paired devices found. I checked on my phones usual bluetooth in settings and it can pick up several paired devices, but they're not visible from this app that we made...

[@marcelocampossilva7024]

This is an excellent tutorial!! I am looking for read data from the Bluetooth and make some routines to search the devices, so , I don't need to pair before. Would you have plans to release some tutorial to perform these as well? Thanks again for sharing your knowledge! I really appreciate it.

[@insu1213]

WoW Such an amazing tutorial Thank you so much!

[@mathewthomas3014]

thank you so much man...... you literally saved my life

[@omakaroto]

please make a similar tutorial but for BLE communication with an arduino, and how to store our datas

[@eingskywalker9116]

I have done exactly as you have shown here, app is working but it doesn't showing paired devices in listview

[@JR_7272]

Async and a couple other things are out of date. does anyone know of an updated one?

[@animongahajime9302]

Excellent Tutorial, but can you please help with update? AsyncTask is deprecated now and i dont know what to do :(

[@ole1907]

File -> Project Structure -> Modules -> Compile Sdk Version -> 28, Then is works

[@syedaffanhameed14]

Hi!, how can we read the RSSI value of that bluetooth signal? can anyone please answer it?

[@rafo5547]

AMAZING tutorial thanks

[@matiassenger2349]

Nice tutorial! Thanks

[@ordinarygamer5917]

How can i use toast inside postexecute in your program? 🙏

[@diegoflores4587]

its so awesome you are the only person how do this witout appinventor ty so much

[@danny117hd]

Consider using the screen magnifier.

[@cabrillafiestera]

Thank you so much from Spain¡

[@ksaweryc]

Is there any possibility to display names of bluetooth devices instead of their MAC Addresses? Thanks in advance! :) (Btw great video!!!)

[@ksaweryc]

OK guys I've figured it by myself :) Instead of ArrayList we can simpy use ArrayList and then we can add elements to our list by using "device.name". Code: val names : ArrayList = ArrayList() if (m_pairedDevices.isNotEmpty()) { for (device : BluetoothDevice in m_pairedDevices) { names.add(device.name) //Log.i("device", ""+device) } } else { toast("No paired BT devices found...") } val adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, names) If I'm wrong in this point please tell me - I'm not so experienced with android studio and Kotlin :)

[@theoberessi6794]

@@ksaweryc I tried to replaced it like you did but the app crashed when i tried to connect to a device. It's because we use the object BluetoothDevice in the other activity, so instead i jest added your code with the alreading existing code : val list : ArrayList = ArrayList() val names : ArrayList = ArrayList() if(m_pairedDevices.isNotEmpty()){ for(device: BluetoothDevice in m_pairedDevices){ list.add(device) names.add(device.name) Log.i("device", ""+device) } } else { Toast.makeText(this, "No paired bluetooth devices found", Toast.LENGTH_SHORT).show() } val adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, names)

[@AceDBahrah]

this is really good tutorial! everything works fine, but can it receive something from arduino??

[@canererhadim3772]

Good question

[@bseyhaOLI]

​@@canererhadim3772 Ben de aynı şeyi araştırıyorum ? Bu sorunu çözebildin mi

[@best_songs_ever3889]

it uses bluetooth or BLE?

[@jonahosterried7832]

What does he exactly send to the Bluetooth module?

[@rc5016]

Great tutorial!! It works !!

[@rikef.7349]

This is a great tutorial, I really like it. I tried the app and everything works, but I couldn't connect to the bluetooth device. The logcat says: couldn't connect Do you know this problem and may know how I can fix it?

[@JamCluster]

I am trying this tutorial several days ago but using a raspberry PI but does not work, anyway, many thanks for the usefull information!

[@Geology0526]

Interesting video but how can we receive datas from an arduino to the application ? (And how can we display it ?)

[@apptaura8131]

Hi Devpax, thanks for the comment. We have a tutorial about reading data from an Arduino via Bluetooth coming very soon.

[@onlytacobell]

I can't wait for this. These tutorials are helpful, but I haven't figured out how to read my Arduino code on my own.

[@fiqrizurani4549]

@@apptaura8131 do you have upload the tutorial?

[@bseyhaOLI]

@@apptaura8131 Where is it ? :)

[@IsraelLopezMascorro]

Great job! I am getting this error "isSocketAllowdBySecurityPolicy start :device null" Some idea? thanks

[@MatejZimic]

Hello, Where can I find Arduino code? Thank You

[@SangPham-dq8br]

I have an error: Inactivity, disconnecting from the service. I don't know how to fix it. Can you help me? Thanks

[@kleanlins]

How can I read data from m_bluetoothSocket instead of write? I just want to show my arduino's data inside the app.

[@kleanlins]

Anyway. I've discovered. Just use Reader. val reader = Reader(m_bluetoothSocket!!.inputStream) reader.nextLine() (depends on your data stream)

[@adiilhammaulana]

@@kleanlins hi, can u share your code ? i am new in kotlin - [e-mail] - thanks

[@AndreasHel197]

could any of you share your code? cant seem to figure out how to read data from the device connected.

[@theoberessi6794]

Hi, can you share your code please ? I can't figure it out :/

[@Medina656]

Thanks, it works!!!

[@beardedkumquat654]

ASyncTask has since been deprecated. Does anybody know an alternative?

[@hannes.b]

Hey, I have the same problem. Have you found an answer yet :)

[@pablotomey9976]

one alternative is Coroutines

[@snowiethetoolguy]

Great tutorial!!! . Can or have you done one on getting data from an Arduino back to Android device. ie sensor data etc??

[@snowiethetoolguy]

Managed to get some code written up in Kotlin.... Thanks for your effort in making these videos. As a noob i reference them often

[@alaanasef5162]

@@snowiethetoolguy i am trying to read data from arduino can you refer me to that code, thanks in advance

[@snowiethetoolguy]

@@alaanasef5162 contact me at [e-mail] .I'll forward you what i have..

[@theoberessi6794]

Hi ! Can you tell us how you did it please ? i've written this code but in a loop but it the progress dialogue of the doInBackground function won't disapear : fun checkReceive(){ if (m_bluetoothSocket != null) { var input = m_bluetoothSocket!!.inputStream var buffer: ByteArray = ByteArray(1024) var bytes: Int try { bytes = input.read(buffer) var incomingMessage = String(buffer, 0, bytes); Toast.makeText(this, incomingMessage, Toast.LENGTH_SHORT).show() } catch (e: IOException){ e.printStackTrace() } } }

[@snowiethetoolguy]

@@theoberessi6794 I've setup a background thread the looks for data received in the BT buffer and acts on that.. whats your email I'll send you some code snippets

[@valentindoche4405]

Good Tutorial

[@richardthibault7473]

Is this a new App or an addition to Part 1

[@apptaura8131]

Hi Richard, thanks for the comment. This video is a continuation from part one, both videos make one app

[@Leo-wz8pu]

HII .. I'm not sure, but I see too much code

[@jorgebh10]

Thank you so much!

[@MrShivamgautam1]

Where is the Arduino code?

[@apptaura8131]

Hi Shivam. We have added a link to where we got the Arduino code in the description.

[@MrShivamgautam1]

Apps In The Sky thanks for the code! Though I have tried this code but it does not work if I change 1 and 0 with 'a' and 'b' in Arduino. So I made the app send 1 or 0 instead and it worked. Great tutorial man!👍

[@bevx2080]

@@MrShivamgautam1 In my case even 1 and 0 doesn't work :(

[@diegoflores4587]

why you make private the fun?

[@apptaura8131]

Hi Diego, thanks for the comment. The reason for making the functions private is because I didn't want other Classes/Activities from calling them. If there is a specific function that you want to know about please let us know.

[@diegoflores4587]

ok ty

[@pavolmeravy961]

Too bad it didn't have a sequel. Getting data into Android.

[@elektronika922]

OMG, we need 2 hours to create one simple BT app to start the LED! How meny we need to create calculator app? 22 days?

[@TorIvanBoine]

If it only would work.

[@felangga]

SOS for the morse code