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Android

Posted by dlpuxdzztg
dlpuxdzztg
8,243 Points

ArrayList in SQLite

I'm trying to create a SQLiteHelper for my 'ListItem' object. This is my code so far:

    private static final String DB_NAME = "easylist.db";
    private static final int DB_VERSION = 1;

    // List table functionality...
    public static final String LISTS_TABLE = "LISTS";
    public static final String LISTS_NAME = "NAME";
    public static final int LISTS_CHECKED = 0;

    public ListSQLiteHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {

    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

    }

However, my ListItem object also has an ArrayList value, which I also intent to save:

    private ArrayList<TaskItem> mListsList; // The list's array of tasks
    private String mListName; // The name of the list
    private int mImportant; // Whether the item is important

Edit: My TaskItem objects have values of their own:

    private String mTaskName; // Name of task
    private int mChecked; // Whether the item is checked

How would I save an ArrayList in an SQLiteHelper object?

1 Answer

Ben Deitch
STAFF
Ben Deitch
Treehouse Teacher
Ben Deitch
Ben Deitch
Treehouse Teacher

I'd probably store the tasks array as a delimited String, and then recreate the tasks when you load the data. For example, if I have to take out the trash and mow the lawn, then I'd use this String (using a tilde ~ for the delimiter): "take out the trash~mow the lawn".

dlpuxdzztg
dlpuxdzztg
8,243 Points

How would I go about saving the other values in a delimited string?

Ben Deitch
Ben Deitch
Treehouse Teacher
Ben Deitch
Ben Deitch
Treehouse Teacher

What other values do you have?

dlpuxdzztg
dlpuxdzztg
8,243 Points

Shoot, I should have mentioned this earlier; each TaskItem object in my list has their own string and int values. I'll post the code for the TaskItem values.

Ben Deitch
Ben Deitch
Treehouse Teacher
Ben Deitch
Ben Deitch
Treehouse Teacher

You just need an extra delimiter: "take out the trash$$$0~mow the lawn$$$1"

Here's some code that shows how to do it (it's in Kotlin but it should be very similar for Java):

      val s = "take out the trash$$$0~mow the lawn$$$1"
      val items: List<String> = s.split("~")
      items.forEach {
        val itemPieces = it.split("$$$")
        val taskName= itemPieces[0]
        val checked = itemPieces[1]
        print("$taskName, $checked")
      }

Prints:

take out the trash, 0
mow the lawn, 1
dlpuxdzztg
dlpuxdzztg
8,243 Points

Interesting, I might actually look into that first before proceeding; this might not be the only case I need this.