Just for anyone also interested in this project, I believe op gets a very impressive implementationon mqtt chatter. But after I tried the default Java backend, it was messy to be honest, So i re-written it into Golang, now

It looks great, everything works fine. So that mine and share a same client with ops, but with different backend.

Here is some screen shot of mine:

The enhancement based on this version, I did:

• Dark mode switch;
• Users can change their profiles directly in Client;
• Send picture support on Linux && Windows;
• Send picture now can save in local, both PC && phone supported;
• Fix some backend SQL query problems in ops version.
• now we support Chinese && Janpaness, input and sending

Finally after fix some bugs in your backend server java code, I got it run now.

But some problems really bad:

1). the messages can not sort by time (not distinguish coming msgs or my msgs, it should natrually sort by time, but now , its not;

2. Can not send Chinese.

3. Can not send picture.

Hi WahidNasri,

I can't find out how to register a user.

After building the app, here is the terminal output (sorry it seems a bit long)

$ flutter run ...

`💪 Running with sound null safety 💪

An Observatory debugger and profiler on SM G991B is available at: http://127.0.0.1:54479/_RRjKnM55QU=/ The Flutter DevTools debugger and profiler on SM G991B is available at: http://127.0.0.1:54488?uri=http%3A%2F%2F127.0.0.1%3A54479%2F_RRjKnM55QU%3D%2F I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 V/InputMethodManager(12701): Starting input: tba=com.example.flutter_mqtt ic=io.flutter.plugin.editing.InputConnectionAdaptor@22a1f65 mNaviBarColor -855310 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false D/InputMethodManager(12701): startInputInner - Id : 0 I/InputMethodManager(12701): startInputInner - mService.startInputOrWindowGainedFocus D/InputTransport(12701): Input channel constructed: 'ClientS', fd=116 D/InputTransport(12701): Input channel destroyed: 'ClientS', fd=109 D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 V/InputMethodManager(12701): Starting input: tba=com.example.flutter_mqtt ic=io.flutter.plugin.editing.InputConnectionAdaptor@5efb8eb mNaviBarColor -855310 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false D/InputMethodManager(12701): startInputInner - Id : 0 I/InputMethodManager(12701): startInputInner - mService.startInputOrWindowGainedFocus D/InputTransport(12701): Input channel constructed: 'ClientS', fd=115 D/InputTransport(12701): Input channel destroyed: 'ClientS', fd=116 W/IInputConnectionWrapper(12701): getExtractedText on inactive InputConnection W/IInputConnectionWrapper(12701): getTextBeforeCursor on inactive InputConnection W/IInputConnectionWrapper(12701): getExtractedText on inactive InputConnection W/IInputConnectionWrapper(12701): getTextBeforeCursor on inactive InputConnection W/IInputConnectionWrapper(12701): getExtractedText on inactive InputConnection W/IInputConnectionWrapper(12701): getTextBeforeCursor on inactive InputConnection E/SpannableStringBuilder(12701): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length E/SpannableStringBuilder(12701): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length E/SpannableStringBuilder(12701): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length E/SpannableStringBuilder(12701): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length D/InsetsSourceConsumer(12701): setRequestedVisible: visible=true, type=13, host=com.example.flutter_mqtt/com.example.flutter_mqtt.MainActivity, from=android.view.InsetsSourceConsumer.show:229 android.view.InsetsController.showDirectly:1437 android.view.InsetsController.controlAnimationUnchecked:1110 android.view.InsetsController.applyAnimation:1417 android.view.InsetsController.show:962 android.view.ViewRootImpl$ViewRootHandler.handleMessage:6146 android.os.Handler.dispatchMessage:106 android.os.Looper.loop:246 android.app.ActivityThread.main:8595 java.lang.reflect.Method.invoke:-2 I/ViewRootImpl@ea15fdfMainActivity: MSG_RESIZED_REPORT: frame=(0,0,1080,2400) ci=(0,80,0,944) vi=(0,80,0,944) or=1 I/ViewRootImpl@ea15fdfMainActivity: [DP] dp(1) 1 android.view.ViewRootImpl.reportNextDraw:10957 android.view.ViewRootImpl.access$1200:256 android.view.ViewRootImpl$ViewRootHandler.handleMessage:6101 I/SurfaceControl(12701): nativeRelease nativeObject s[-5476376677826290144] I/SurfaceControl(12701): nativeRelease nativeObject e[-5476376677826290144] I/SurfaceControl(12701): assignNativeObject: nativeObject = 0 Surface(name=null)/@0x167b48a / android.view.SurfaceControl.readFromParcel:1117 android.view.IWindowSession$Stub$Proxy.relayout:1820 android.view.ViewRootImpl.relayoutWindow:9005 android.view.ViewRootImpl.performTraversals:3360 android.view.ViewRootImpl.doTraversal:2618 android.view.ViewRootImpl$TraversalRunnable.run:9971 android.view.Choreographer$CallbackRecord.run:1010 android.view.Choreographer.doCallbacks:809 android.view.Choreographer.doFrame:744 android.view.Choreographer$FrameDisplayEventReceiver.run:995 I/SurfaceControl(12701): nativeRelease nativeObject s[-5476376677826253632] I/SurfaceControl(12701): nativeRelease nativeObject e[-5476376677826253632] I/SurfaceControl(12701): nativeRelease nativeObject s[-5476376677826290032] I/SurfaceControl(12701): nativeRelease nativeObject e[-5476376677826290032] I/SurfaceControl(12701): nativeRelease nativeObject s[-5476376677826249488] I/SurfaceControl(12701): nativeRelease nativeObject e[-5476376677826249488] I/ViewRootImpl@ea15fdfMainActivity: Relayout returned: old=(0,0,1080,2400) new=(0,0,1080,2400) req=(1080,2400)0 dur=16 res=0x1 s={true -5476376672993932736} ch=false fn=37 I/ViewRootImpl@ea15fdfMainActivity: [DP] pd() Asnyc report W/libEGL (12701): EGLNativeWindowType 0xb400006e55f60a50 disconnect failed I/ViewRootImpl@ea15fdfMainActivity: [DP] pdf(0) 1 android.view.ViewRootImpl.lambda$performDraw$1$ViewRootImpl:4668 android.view.-$$Lambda$ViewRootImpl$DJd0VUYJgsebcnSohO6h8zc_ONI.run:6 android.os.Handler.handleCallback:938 I/ViewRootImpl@ea15fdfMainActivity: [DP] rdf() I/SurfaceControl(12701): nativeRelease nativeObject s[-5476376677826287232] I/SurfaceControl(12701): nativeRelease nativeObject e[-5476376677826287232] D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 V/InputMethodManager(12701): Starting input: tba=com.example.flutter_mqtt ic=io.flutter.plugin.editing.InputConnectionAdaptor@2dad660 mNaviBarColor -855310 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false D/InputMethodManager(12701): startInputInner - Id : 0 I/InputMethodManager(12701): startInputInner - mService.startInputOrWindowGainedFocus D/InputTransport(12701): Input channel constructed: 'ClientS', fd=111 D/InputTransport(12701): Input channel destroyed: 'ClientS', fd=115 W/IInputConnectionWrapper(12701): getExtractedText on inactive InputConnection W/IInputConnectionWrapper(12701): getTextBeforeCursor on inactive InputConnection D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 D/InputMethodManager(12701): SSI - flag : 0 Pid : 12701 view : com.example.flutter_mqtt D/InputMethodManager(12701): view is not EditText D/InputMethodManager(12701): prepareNavigationBarInfo() DecorView@b50f53d[MainActivity] D/InputMethodManager(12701): getNavigationBarColor() -855310 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 0 I/ViewRootImpl@ea15fdfMainActivity: ViewPostIme pointer 1 I/flutter (12701): 1-2021-09-23 13:29:13.403568 -- MqttClient::connect - keep alive is enabled with a value of 60 seconds I/flutter (12701): 1-2021-09-23 13:29:13.407537 -- MqttConnectionKeepAlive:: Initialised with a keep alive value of 60 seconds I/flutter (12701): 1-2021-09-23 13:29:13.407654 -- MqttConnectionKeepAlive:: Disconnect on no ping response is disabled I/flutter (12701): 1-2021-09-23 13:29:13.409169 -- MqttConnectionHandlerBase::connect - server 172.16.14.99, port 1883 I/flutter (12701): 1-2021-09-23 13:29:13.411321 -- SynchronousMqttServerConnectionHandler::internalConnect entered I/flutter (12701): 1-2021-09-23 13:29:13.411491 -- SynchronousMqttServerConnectionHandler::internalConnect - initiating connection try 0, auto reconnect in progress false I/flutter (12701): 1-2021-09-23 13:29:13.411738 -- SynchronousMqttServerConnectionHandler::internalConnect - insecure TCP selected I/flutter (12701): 1-2021-09-23 13:29:13.412121 -- SynchronousMqttServerConnectionHandler::internalConnect - calling connect I/flutter (12701): 1-2021-09-23 13:29:13.412846 -- MqttNormalConnection::connect - entered`

Also I couldn't find the documentation, so I added the dependency into the same directory as this repository and apparently I can run the application, but in order to login, I must register, right?

Please check my powerful chatbot base on Python SDK:

Hi. I have made writen a chatbot based on this client possible!

And, it was really powerful and convenient to make a bot for anyone.

I am so happy to share the final version based on flutter-mqtt-chat-client, thanks for original ops wonderful job.

For future any body interested on this project:

• You can found python SDK on opensource git url: https://github.com/jinfagang/alfred
• If you want make a chatbot, you can using my another opensource which will be available soon
• You can built any command, function based on your bot and MQTT service! For example, using ESP8266 to control your light!

[ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: FormatException: Unexpected character (at character 2)
{id: e74d8c82-626c-419b-b393-ab6bddcb093e, presenceType: Away, type: Presen...
 ^

#0      _ChunkedJsonParser.fail (dart:convert-patch/convert_patch.dart:1405:5)
#1      _ChunkedJsonParser.parse (dart:convert-patch/convert_patch.dart:935:48)
#2      _parseJson (dart:convert-patch/convert_patch.dart:40:10)
#3      JsonDecoder.convert (dart:convert/json.dart:506:36)
#4      JsonCodec.decode (dart:convert/json.dart:157:41)
#5      jsonDecode (dart:convert/json.dart:96:10)
#6      new MqttOnlineReader.<anonymous closure> (package:flutter_mqtt/MqttImpl/MqttOnlineReader.dart:31:41)
#7      _rootRunUnary (dart:async/zone.dart:1436:47)
#8      _CustomZone.runUnary (dart:async/zone.dart:1335:19)
#9      _CustomZone.runUnaryGuarded (dart:async/zone.dart:1244:7)
#10     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:341:11)
#11     _DelayedData.perform (dart:async/stream_impl.dart:591:14)
#12     _StreamImplEvents.handleNext (dart:async/stream_impl.dart:706:11)
#13     _PendingEvents.schedule.<anonymous closure> (dart:async/stream_impl.dart:663:7)
#14     _rootRun (dart:async/zone.dart:1420:47)
#15     _CustomZone.run (dart:async/zone.dart:1328:19)
#16     _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
#17     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
#18     _rootRun (dart:async/zone.dart:1428:13)
#19     _CustomZone.run (dart:async/zone.dart:1328:19)
#20     _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
#21     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
#22     _microtaskLoop (dart:async/schedule_microtask.dart:40:21)
#23     _startMicrotaskLoop (dart:async/schedule_microtask.dart:49:5)

when sending image