updating particular item in list

Question

I have an list of customer object. I need to read them from shared preferences and check for particular object by id with my new object and replace the old one in list with new object and write it to back to pref. This is what I am doing..Is it right?

List<School> schools = readFromPref();
ListIterator<School> iterator = schools.listIterator();
while (iterator.hasNext()) {
School oldSchool = iterator.next();
if (oldSchool.getId().equalsIgnoreCase(newSchool.getId())) {
        iterator.set(newSchool);
        schools.add(newSchool);
    }
}
writeToPref(schools);

@BaluSangem there is difference between List and `listView` – Abdul Kawee Feb 15 '18 at 10:32 — Abdul Kawee, Feb 15 '18 at 10:32
Oh Sorry my bad @AbdulKawee – Balu Sangem Feb 15 '18 at 10:35 — Balu Sangem, Feb 15 '18 at 10:35

Viraj Patel · Answer 1 · 2018-02-15T11:14:39.517

You can use Enhanced For loop to get and update data in your ArrayList.

ArrayList<School> schools = readFromPref();
            int i=0;
            for(School oldSchool : schools){  //Enhanced For loop
                if(oldSchool.getId().equalsIgnoreCase(newSchool.getId())){
                    oldSchool.setId(newSchool.getId());
                    schools.set(i, oldSchool);
                }
                i++;
            }
            writeToPref(schools);

Here is the link of how to save and retrive Object from SharedPreference using Gson.

score 0 · Answer 2 · answered Feb 15 '18 at 10:46

0

Remove schools.add(newSchool); because iterator.set(newSchool); is updating your school list already.

And everything looks good

answered Feb 15 '18 at 10:46

Balu Sangem

712
4
16

score 0 · Answer 3 · answered Feb 15 '18 at 11:55

0

Store your data in form of map where key will be the id of your object,and update the object on key basis

answered Feb 15 '18 at 11:55

yogesh chouhan

111
8

updating particular item in list

3 Answers3