I want to use a json file with a list containing a lot of li

Question

I want to use a json file with a list containing a lot of lists Each child list contains two unicode strings I want to be able to access a random list using my Android app

czuckie · Answer

< Minty> Start with a small representation of your data structure e g ``` questions q q1 a a1 a2 a3 ca 1 q q2 a a1 a2 a3 ca 0 ``` And get your system parsing that correctly then work on selecting random questions from that

czuckie · Answer

then you can scale up and figure out how things may work

czuckie · Answer

you might find if you have tons of questions it will be worth while ingesting them into a SQLite database instead of parsing JSON every time you want to get a selection of questions

Minty · Answer

``` Q1 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 Discussion Method can be used when n A The topic is very difficult u00a0 B The topic is easy n C The topic is difficult u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 D All of the above n C Q2 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 Which of the following is a teaching aid n A Working Model of Wind Mill u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 B Tape Recorder n C 16mm Film Projector u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 u00a0 D All the above n D ```

Minty · Answer

My data is more like this

czuckie · Answer

what do you think of the data structure

Minty · Answer

It s like Question1 and choices Answer Q2 A

czuckie · Answer

are you in control of the data structure

czuckie · Answer

or has a client given it you

Minty · Answer

It s a question paper data that I extracted using regex from a text file

Minty · Answer

I converted it to json in Python

Minty · Answer

``` data = for r in re findall r Q d+ =Q d+ soup text flags=re S data qa = rs = re findall r Q d+ =Answer a dA D r strip flags=re S ra = re findall r Answer a dA D r strip for rse in rs print rse data qa append rse for rsa in ra if ra index rsa == 0 print The answer is + rsa replace Answer replace strip data qa append rsa replace Answer replace strip print data append data qa for d in data if len d lt 2 data remove d print d jdump = json dumps data with file qNa json w+ as f f write jdump ```

czuckie · Answer

ok cool I would recommend for your own sanity sticking with either u00a0 or n but not both smile

czuckie · Answer

this shouldn t be too tough though

czuckie · Answer

each of the questions could be represented nicely using a `data class Question val question String val answer String `

Minty · Answer

So is the above representation any good for quiz type things ` Question1 and choices Answer Q2 A `

czuckie · Answer

given that you re scraping it from a text block it ll have to do

czuckie · Answer

the reason I was digging was if you had the data in a format of question and then a list of answers and the correct answer

czuckie · Answer

you could make the quiz more dynamic and randomise the order of answers etc

czuckie · Answer

but since the question answers are encoded in the question that s not really viable

Minty · Answer

I m supposed to create the `data class` outside `oncreate` right Can I do it in the main activity classs

czuckie · Answer

you can yeah

Minty · Answer

But I can call data using `index` in a list How do I do that with a data class I still don t understand the concept of data class i guess I ll have to look it up

czuckie · Answer

``` class MainActivity AppCompatActivity data class Question val question String val answer String fun parseQuestions rawQuestionJson String List lt Question gt TODO Parse json override fun onCreate savedInstanceState Bundle super onCreate savedInstanceState setContentView R layout activity main parseQuestions Question 1 A Question 2 B ```

czuckie · Answer

for example

czuckie · Answer

so if you imagine

czuckie · Answer

`class Question val question String val answer String `

czuckie · Answer

if I did ``` val q1 = Question q1 a val q2 = Question q1 a if q1 == q2 println They are equal ```

czuckie · Answer

they are equal would not be printed

czuckie · Answer

if I used a data class kotlin will provide equality methods making that pass

czuckie · Answer

data classes are useful for identifying clumps of data that have a particular meaning

czuckie · Answer

once you parse the JSON you can then go about randomising access to the list

Minty · Answer

How do I dynamically create q1 q2 Would I parse json on the fly and get the data index I want and assign it to q1

Minty · Answer

data 2 question3

czuckie · Answer

how many questions are you dealing with

Minty · Answer

I did a len data there seem to be 1457

czuckie · Answer

that s an impressive amount of questions

czuckie · Answer

you wouldn t want to parse that everytime you wanted a question

czuckie · Answer

I d definitely consider whacking the questions in a database BUT

Minty · Answer

Question papers from 2004 2017 lol

czuckie · Answer

you should be able to get away with ``` private fun parseQuestions rawQuestionJson String List lt Question gt val result = mutableListOf lt Question gt val questionArray = JSONArray rawQuestionJson for i in 0 questionArray length val question = questionArray getJSONArray i result += Question question getString 0 question getString 1 return result ```

czuckie · Answer

line by line we create a mutable list to store questions in We then parse the input JSON we know it s a JSONArray We then iterate over all the child arrays We then add a new Question object to our result list which we can do because it s mutable consisting of the two strings in the child question json array object We then result the result

Minty · Answer

So you add created Question object instances to list That was what was bothering me Thanks BTW is JSONArray an inbuilt function

czuckie · Answer

``` class MainActivity AppCompatActivity data class Question val question String val answer String private fun parseQuestions rawQuestionJson String List lt Question gt val result = mutableListOf lt Question gt val questionArray = JSONArray rawQuestionJson for i in 0 questionArray length val question = questionArray getJSONArray i result += Question question getString 0 question getString 1 return result override fun onCreate savedInstanceState Bundle super onCreate savedInstanceState setContentView R layout activity main var tenQuestions = parseQuestions Question 1 A Question 2 B shuffled take 10 TODO Display ten questions ```

czuckie · Answer

JSONArray is part of `org json` which is shipped with android

czuckie · Answer

`var tenQuestions = parseQuestions Question 1 A Question 2 B shuffled take 10 ` may look like black magic but

czuckie · Answer

``` var tenQuestions = parseQuestions JSONHERE shuffled Randomises the order of list items take 10 Take the first 10 items from the list ```

czuckie · Answer

assuming you want a random collection of questions

czuckie · Answer

subjecting someone to 1407 questions is going to be brutal lol

czuckie · Answer

if this is to help you revise etc

czuckie · Answer

I would really investigate the possibility of teasing out the answer from the questions

czuckie · Answer

it ll help you learn the right answer rather than the right letter wink

Minty · Answer

It s a multiple choice I have created logic for buttons I check the string A B C D and set the answer int to 1 2 3 4 and check in Button

Minty · Answer

What do you mean by teasing out

czuckie · Answer

so if all the questions take the format

czuckie · Answer

This is a question that needs to be answered by one of the following answers A Answer A B Answer B C Answer C D Answer D Correct Answer C Then I would parse the input data to extract This is a question that needs to be answered by one of the following answers the individual answers The correct answer

czuckie · Answer

and I d transform that into the format I explained above

czuckie · Answer

then you could randomise the display of the answers

czuckie · Answer

since you know what the correct answer is you always know that if you display answer C first the first button would be the correct one

czuckie · Answer

any who Lunch time ask questions though

Minty · Answer

I can maybe give a option to display answer too But my main focus is to build a quiz This is my first Kotlin project and I m in love with kotlin already

Minty · Answer

Oh You mean randomising the order of the choices

Minty · Answer

That ll be useful but I have to parse the data first Regex to the rescue

Minty · Answer

But I want to build a simple working project first and add features later

Minty · Answer

Since this is my first project I want to take it easy and build the simple parts first a proof of concept and add features later

Minty · Answer

BTW what do I have to import for JSONArray

Minty · Answer

Never mind imported it

czuckie · Answer

your approach is perfect

czuckie · Answer

build the simplest thing first

czuckie · Answer

go end to end

czuckie · Answer

then beef it up as you go

czuckie · Answer

agile all the way +1