how can I store different value in different ArrayList in android

Question

I'm working with string value like this String result "aa,bb,cc,dd,ee".

And already split it into aa bb cc dd ee with

qrList = result.getContents().toString().split("\\,");
List<String> resultToString= new ArrayList(Arrays.asList(qrList));

Then I create four ArrayLists.

 ArrayList<String> strA = new ArrayList();
 ArrayList<String> strB = new ArrayList();
 ArrayList<String> strCD = new ArrayList();
 ArrayList<String> strE = new ArrayList();

When I use this code below to store string into each new ArrayList.

for(int count=0; count<resultToString.size(); count++){
    //separate string to array list
    if(count%5==0){
        strA.add(resultToString.get(count));
    }else if(count%5==1){
        strB.add(resultToString.get(count));
    }else if(count%5==2||count%5==3){
        strCD.add(resultToString.get(count));
    }else if(count==4){
        strE.add(resultToString.get(count));
    }

The correct result would be

strA stored aa
strB stored bb
strCD stored cc and dd
strE stored ee

It doesn't work because I only get the index value at 0 (strA stored aa). What should I do to improve my code?

Do you split work fine? I tried it manually like "aa,bb,cc,dd,ee".toString().split("\\,"); and then you code works fine. — motis10
– motis10, Commented Jun 8, 2017 at 11:03
What you said is not possible. count==4 must be true for your given input — OneCricketeer
– OneCricketeer, Commented Jun 8, 2017 at 11:04

Pavneet_Singh · Accepted Answer · 2017-06-08 11:06:52Z

2

Simply use startsWith and add appropriate values to list

    for(int count=0; count<resultToString.size(); count++){
        //separate string to array list
        String s = resultToString.get(count);

        if(s.startsWith("a")){
            strA.add(s);
        }else if(s.startsWith("b")){
            strB.add(s);
        }else if(s.startsWith("c")||s.startsWith("d")){
            strCD.add(s);
        }else if(s.startsWith("e")){
            strE.add(s);
        }
    }

edited Jun 8, 2017 at 11:06

answered Jun 8, 2017 at 11:01

Pavneet_Singh

37.5k5 gold badges57 silver badges71 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

earthw0rmjim Over a year ago

Instead of giving an alternate solution please explain why his code isn't working.

Pavneet_Singh Over a year ago

@earthw0rmjim by OP What should I do to improve my code

OneCricketeer Over a year ago

I think the strings are arbitrary

Pavneet_Singh Over a year ago

@earthw0rmjim i couldn't find anything wrong so i went for testing and nothing wrong again , it must be something else wrong somewhere , though i suggested a bit clear approached

Koshux · Accepted Answer · 2017-06-08 11:22:05Z

Modulus operator describes the remainder of your equation. Let us show and explain an example:

As explained in this documentation, performing modulus between two values will only show you the remainder value. For e.g. 8 % 3 == 2 because 8 divided by 3 leaves a remainder of 2.

The reason your code is not showing your desired results is due to the usage of your modulus operator. Regarding improving your code, I can tell that all you wanted is to use the Array List index so as to add the string from the resultToString Array List.

Therefore I would modify your loop in the following manner:

for(int count=0; count < resultToString.size(); count++) {
  //separate string to array list
  if (count == 0){
     strA.add(resultToString.get(count));
  } else if (count == 1){
     strB.add(resultToString.get(count));
  } else if (count == 2 || count == 3){
     strCD.add(resultToString.get(count));
  } else if (count == 4){
     strE.add(resultToString.get(count));
  }
}

An alternative is to loop directly on the resulting String[] and use that relative counter in the for loop for e.g.

String[] qrList = results.getContent().toString().split("\\,");

for(int count = 0; count < qrList.length; count++) {
  //each index represents the split string e.g
  // [0] == "aa"
  // [1] == "bb"
  // [2] == "cc"
  // [3] == "dd"
  // [4] == "ee"
  if (count == 0){
     strA.add(qrList[count]);
  } else if (count == 1){
     strB.add(qrList[count]);
  } else if (count == 2 || count == 3){
     strCD.add(qrList[count]);
  } else if (count == 4){
     strE.add(qrList[count]);
  }
}

To Koshux,When I use your code to test, it can't store any value in the ArrayList.

Collectives™ on Stack Overflow

how can I store different value in different ArrayList in android

2 Answers 2

4 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related