CodeProject Latest postings for Mobile

Forum Guidelines - PLEASE READ

Chris Maunder — Tue, 28 Jul 2009 12:38:00 GMT

When posting your question please:

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When answering a question please:

Read the question carefully
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cheers,
Chris Maunder

The Code Project Co-fou

What tech stack is used in grocery app development?

Suheb Multani — Fri, 28 Jun 2024 14:33:00 GMT

On what technology grocery app is usually developed

entry level tools to deliver web app notifications

M.I.T.I — Tue, 11 Jun 2024 14:59:00 GMT

I found that this could perhaps be a good entry level solution in order to deliver notifications to a mobile friendly React website: implement Push Notifications by using Browser Notifications API
https://developer.mozilla.org/en-US/docs/Web/API/Notifications_API/Using_the_Notifications_API or use for example this framework: https://pushjs.org/
If anyone has some experience using any of the above of competing solutions that would be most appreciated

Error using google_maps_flutter: ^2.5.0 in flutter

Luis M. Rojas — Mon, 04 Dec 2023 13:06:00 GMT

Hello everybody:
I am new in flutter, using flutter version: 3.16.0 a Dart (SDK) 3.2.0
I had checked everything the manuals and forums say (also flutter), but I still have this error:

<pre>C:\Mapas\mapas\android\app\src\debug\AndroidManifest.xml Error:
	uses-sdk:minSdkVersion 19 cannot be smaller than version 20 declared in library [:google_maps_flutter_android] C:\Mapas\mapas\build\google_maps_flutter_android\intermediates\merged_manifest\debug\AndroidManifest.xml as the library might be using APIs not available in 19
	Suggestion: use a compatible library with a minSdk of at most 19,
		or increase this project's minSdk version to at least 20,
		or use tools:overrideLibrary="io.flutter.plugins.googlemaps" to force usage (may lead to runtime failures)

Help Backend - OLX Clone App in React Native

Member 16110642 — Mon, 09 Oct 2023 11:15:00 GMT

I am currently working on setting up the backend for a project template I obtained from GitHub. The frontend setup is complete, however, I've hit a roadblock while integrating the backend, which has brought my progress to a standstill. The issue arises when attempting to connect the frontend with the data from a GraphQL query using Firebase's Realtime Database. Despite numerous attempts to resolve this problem, I have been unable to make any headway, and it's becoming increasingly frustrating.

The tech stack involved in this project includes React Native, GraphQL, and Firebase, as detailed in the repository: [https://github.com/Ninjas-Code-official/olx-app-clone-backend](https://github.com/Ninjas-Code-official/olx-app-clone-backend). 

At this point, I am seeking someone with expertise in these technologies to provide assistance, and if possible, code along with me to resolve this issue. The importance of getting past this hurdle cannot be overstated as it is critical to the progress and eventual success of the project. The complexity and specificity of the problem require a level of understanding and experience that I currently lack, hence the need for external help.

I am more than willing to collaborate and learn in the process. This challenge has become a significant impediment, and any assistance to overcome it would be immensely valued. The goal is to not only resolve the current issue but to also foster a learning environment that will prevent similar challenges in the future. 

I am highly motivated to get this project back on track and would greatly appreciate any help that can be provided. Your expertise and willingness to assist would mean a great deal and would significantly contribute towards moving the project forward.

Significance of AI in mobile app development

kesavan santhinikethan — Sat, 29 Oct 2022 10:47:00 GMT

What is the importance of incorporating AI into the development of mobile apps?

Food Delivery App Development

nithin sethu — Fri, 28 Oct 2022 13:25:00 GMT

Which is the best model for developing a  Food Delivery App?. Cloned app or a custom app, or an MVP?

can anyone help me to solve this error?

Member 15796466 — Thu, 13 Oct 2022 10:51:00 GMT

import 'package:flutter/material.dart';
import './practice2.dart';
import './practice3.dart';
void main()
{
  runApp(MaterialApp(home:Akanksha()));
}
class Akanksha extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return AkankshaState();
  }
}

class AkankshaState extends State<Akanksha>{
  final questions=const[
    {'questionText':'what is your favourite colour?','answers':['black','green','blue'],
    },
    {'questionText':'what is your fav drama?','answers':['black','green','blue'],
    },
    {'questionText':'what is your favourite animal?','answers':['black','green','blue'],
    },
  ];
  var _questionIndex=0;
  void answerQuestion(){
    // var aBool=true;
    // aBool=false;
    setState((){
_questionIndex= _questionIndex+1;
    });
print(_questionIndex);
    if (_questionIndex<questions.length){print('We have more question!');}
else{print('no more questions!');}
  }
  @override
  Widget build(BuildContext context) {


    return Scaffold(
      appBar:AppBar(backgroundColor: Colors.deepOrange,
          title:Text('my app')),
      body:_questionIndex<questions.length ?
      Column(
         //mainAxisAlignment: MainAxisAlignment,
         children: [
           Question( questions[_questionIndex]['questionText'], ), ...
           (
               questions[_questionIndex]['answers'] as List).map((answer){
  return Answer(answerQuestion , answer);
      }).toList(),
// Answer(answerQuestion),
//
// Answer(answerQuestion),
//
//            Answer(answerQuestion),
         ],
       ): Center(child:Text('you did it!')),

    );
  }
}

import 'package:flutter/material.dart';
import './practice2.dart';
import './practice3.dart';
void main()
{
  runApp(MaterialApp(home:Akanksha()));
}
class Akanksha extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return AkankshaState();
  }
}

class AkankshaState extends State<Akanksha>{
  final questions=const[
    {'questionText':'what is your favourite colour?','answers':['black','green','blue'],
    },
    {'questionText':'what is your fav drama?','answers':['black','green','blue'],
    },
    {'questionText':'what is your favourite animal?','answers':['black','green','blue'],
    },
  ];
  var _questionIndex=0;
  void answerQuestion(){
    // var aBool=true;
    // aBool=false;
    setState((){
_questionIndex= _questionIndex+1;
    });
print(_questionIndex);
    if (_questionIndex<questions.length){print('We have more question!');}
else{print('no more questions!');}
  }
  @override
  Widget build(BuildContext context) {


    return Scaffold(
      appBar:AppBar(backgroundColor: Colors.deepOrange,
          title:Text('my app')),
      body:_questionIndex<questions.length ?
      Column(
         //mainAxisAlignment: MainAxisAlignment,
         children: [
           Question( questions[_questionIndex]['questionText'], ), ...
           (
               questions[_questionIndex]['answers'] as List).map((answer){
  return Answer(answerQuestion , answer);
      }).toList(),

         ],
       ): Center(child:Text('you did it!')),

    );
  }
}
 :wtf:

-----------------------------------------------

import 'package:flutter/material.dart';
class Question extends StatelessWidget {
 //final String questionText;
 // Question(this.questionText);
 String questionText;
 Question(this.questionText);
  @override
  Widget build(BuildContext context) {
    return Container(
      margin: EdgeInsets.all(20),
        width: double.infinity,
       child:Text(questionText,style:TextStyle(fontSize: 25),textAlign: TextAlign.center,)

       // child: Text(questionText,style:TextStyle(fontSize: 25),textAlign:TextAlign.center,)
   );
  }
}

------------------------------------------------------------------

import 'package:flutter/material.dart';
class Answer extends StatelessWidget {
  final Function selectHandler;
  final String answerText;
Answer(this.selectHandler, String this.answerText);
  @override
  Widget build(BuildContext context) {
    return Container(
      width:double.infinity,
      child:ElevatedButton(
          style: TextButton.styleFrom(backgroundColor: Colors.blueGrey,
              shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10))),
          onPressed: ()=> selectHandler(),
          child:Text(answerText,style:TextStyle(color:Colors.white,fontSize:20))),
    );
  }
}

Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.'

Luis M. Rojas — Fri, 22 Jul 2022 17:18:00 GMT

Hello, I am new in XAMARIN, i have a simple APP in VS2022.
Here is part of the code:

public interface IRepository
   {
       [Get("/package/")]
       Task<Resultado> GetAllData();
   }

public class PaqueteServicio
   {
       public const string API_BASE_URL = "http://www.mi.traelopaq.net/listarpaqjson.php?text1=2264&text2=pOADSIQMASD.O398AJas&KEYAPI=ODUTRAS.9di23821@ldpli2skjs43&KEYPASo=OASmsjdu38IO1p29AA93JA0OD9K1221";

       private IRepository repo;
       public PaqueteServicio()
       {
           repo = RestService.For<IRepository>(API_BASE_URL);
       }
       public Task<Resultado> Get()
       {
           return repo.GetAllData();
       }
   }

Package.cs

public class Package
{
        [JsonProperty("peso")]
        public string Peso { get; set; }

        [JsonProperty("tracking_number")]
        public string TrackingNumber { get; set; }

        [JsonProperty("contenido")]
        public string Contenido { get; set; }

public class Resultado
  {
      [JsonProperty("results")]
      public Package[] Results { get; set; }
  }

Main:

class MainViewModel : BaseViewModel
   {
       private readonly PaqueteServicio paqueteServicio;
       private List<Package> paqueteList;
       public List<Package> PaqueteList
       {
           get => paqueteList;
           set
           {
               paqueteList = value;
               RaisePropertyChanged();
           }
       }
       public ICommand ClickCommand => new Command(ClickCommandExecute);

       private async void ClickCommandExecute()
       {
           var response= await paqueteServicio.Get();  //This line is the one with the Error
           PaqueteList = response.Results.ToList();
       }

       public MainViewModel()
       {
           paqueteServicio = new PaqueteServicio();
       }
   }

Is is realistic to make money from a small mobile/tablet app?

Patrick Skelton — Sun, 20 Mar 2022 10:54:00 GMT

Is is realistic to make money from a small mobile/tablet app? That's a ridiculously vague question, I know, so I'll add a bit of background.

I'm coming to the end of a long project that has increased my experience of mobile application programming (using Xamarin and C#). I don't yet have another contract lined up. What I do have are ideas for two or three small applications, the smallest of which may take only about a month-or-so to get to a first version. Judging by other applications I have seen in the app store, I'd say that my application is something someone might pay £0-99 or £1-99 to get the Pro version (which I'd advertise in the Standard version). And I am wondering if I can make a few quid?

I don't expect to make much but even £10-£50 per month is still money in the bank. I don't seem to be able to get any kind of answer anywhere whether this is remotely likely. I guess I am hoping that one of you out there has personal experience of this and could at least sketch me an outline of whether this is even worth a go.

Absolutely any advice would be extremely welcome.

- Patrick

Thank you to anyone taking the time to read my posts.

How to get started - app android and ios

David Mikkelsen 2021 — Wed, 02 Mar 2022 19:06:00 GMT

Hi
I program business logik in ERP systems in Visual Studio with vb.net and C#.
Now I would like to try and learn to make app's so maybe one day and I can make app's that show business data.

But beeing new to this I find it difficult to get started. There is a lot of new words I don't know the meaning of and it is difficult to find out how to best start making app's.
I started looking at Xamarin beeing used to VS and all, but I just found out that this seems to be obsolete?
I would like to only write code once and use it on both android and ios - but is this realistic?

So...
Any recommendations where to start?
A good place be be guided through which buzz words I need to know about and the technology they represent?
Should I use Xamarin, or Flutter or...???
Hands on example that makes it easy to learn by doing?

Any recommendations will be appreciated

Another old dog that wants to learn new tricks

SMPP Protocol

Member 12847677 — Wed, 16 Feb 2022 08:07:00 GMT

i want send bulk of messages using SMPP protocol with c#

EVC++ dummy target

charlieg — Wed, 05 Jan 2022 16:19:00 GMT

I know I'm going way, way back here, but maybe someone here has done this a long time ago.... I have a multiplatform project I support - the older platforms use EVC++ 4.0 to build the application, the newer platform uses VS2008 Professional.

In VS2008, I can create a folder, add many subprojects into it, and compile all of them by simply right mouse clicking on the folder and select Build. In effect, the folder is a dummy target, and VS2008 just knows how to build the proper dependency tree.

I'd like to do the same in EVC++, but it has no folder option at the project / workspace level. I can create a simple project and establish dependencies to the subprojects, but EVC++ insists on having an output target of some type.

Anyone know how to fake out EVC++? I know I'm grasping here If I were back in Unix land, I'd just edit my make file and create the dummy target manually. Hmmm, possibilities here.

Charlie Gilley

“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759

Has never been more appropriate.

programming dart

olivier Dakouri — Mon, 04 Oct 2021 18:24:00 GMT

I am looking for a solution to this problem please

Write a calculation function allowing to perform an operation on two numbers according to a given operator.

In addition to the two numbers it will be necessary to pass a 3rd parameter defining the type of operation to be done: + (addition), - (subtraction), * (multiplication), / (division)

How to permanently set location for Android 1Weather?

swampwiz — Sun, 18 Jul 2021 21:35:00 GMT

I was able to stop it from automatically coming up with the location of where my Wifi service is (which for some reason is about 350 miles away), and added a few cities, and selected one of the cities, but then when I got out of the app and back to the Android desktop (or whatever it's called), I get one of the other cities in the list of cities. And I don't feel like having to reboot.

Why is there a difference between the page style in split view and simulated window (in Xamain)?

Alex Dunlop — Sat, 19 Jun 2021 06:03:00 GMT

There is always some difference in the position of my controls in the simulated screen and the split view (Visual Studio 2019). Which one is correct? How can I make them similar?

https://s4.uupload.ir/files/107153-1_j5q.png[^]

dataTable react native

Member 14782979 — Wed, 28 Apr 2021 08:05:00 GMT

hello I want to know how to retrieve the data from an API and display this data in an array for example if I have an array that contains the users how to form an array with their name, first name, city etc ... put the values that I retrieved from an API in react native
please help me with full example

How to get data from GSM module to android studio without including the server?

Rocking Kapil — Sun, 21 Mar 2021 10:05:00 GMT

I am trying to get GSM data into the android studio. However, this data must not come through the server. Basically, sending the data from GSM module from Arduino to android application without including any type of server such as Firebase. Need help

How much does it cost to develop Clubhouse-like application?

Clarence Kennedy — Wed, 17 Mar 2021 15:09:00 GMT

Want to order a clone of Clubhouse from app development company. How much it would cost ?