Saving an ArrayList of custom objects in internal storage

Question

I have an ArrayList of RowItem where RowItem Class have following variables :

public class RowItem
{
   private Bitmap photo;
   private String photoURL ;
   private int online_status;
   private String name;
   private String last_seen;
   private int delete;
   //Getters and Setters ...
}

I want to save this ArrayList into internal storage. Here is the list of things I have already tried but aren't working :

1. Implemented exclusion strategy as indicated in here. Excluded Bitmap from saving as I am Lazy Loading Images From URLs to ListView. But I am still getting errors like :

    java.lang.RuntimeException: Unable to pause activity {com.awesome.clique/com.awesome.clique.Home}: java.lang.IllegalArgumentException: class android.text.BoringLayout declares multiple JSON fields named mPaint.
   

   If I am saving in onPause() or onStop() using SharedPreferences(using gson) or Files.

2. Overridden methods of readObject and writeObject for RowIem class. But it still kept on giving the above error.

Now I am out of options now. I do now think that saving the ArrayList in SQLite database maybe feasible, but I do not know how to save this list into SQLite databse as I have no idea about SQLite and in a glance it seemed very complex. Please help me out.

Answer 1

I would suggest you to look at ORMLite, it will simplify how you work with SQLite.

Take a look at how I implemented a simple model here: https://github.com/slidese/BabyFeed/blob/master/src/se/slide/babyfeed/model/FeedLog.java

And have a look (at that same project) how you work with it, it pretty simple.

Your code would look something like this:

@DatabaseTable
public class RowItem
{
   @DatabaseField(generatedId = true)
   private int id;

   @DatabaseField
   private Bitmap photo;

   @DatabaseField
   private String photoURL;

   @DatabaseField
   private int online_status;

   @DatabaseField
   private String name;

   @DatabaseField
   private String last_seen;

   @DatabaseField
   private int delete;

   //Getters and Setters ...
}

And then:

DatabaseManager.getInstance().addRowItem(row);

You create these helper methods, for example a delete could look like this:

public void deleteRowItem(RowItem row) {
    try {
        getHelper().getRowDao().delete(row);
    } catch (SQLException e) {
        e.printStackTrace();
    }
}