Question

The current app that I’m creating is using gson to parse and populate a listview via a remotely hosted json file. I have an options menu inside my app that I would like to use that will allow users to select/deselect items so that they will either show (if selected) or not show (if deselected) inside the listview that is shown on screen via the remote json file.

My question is, how do I go about implementing this function? Can I simply use a shared preferences? Is it even possible to hide certain list items while using a json file?

I’ve been having a lot of trouble trying to figure this out so any and all help will be greatly appreciated.

Answer 1

Using a custom ArrayAdapter you could “choose” what is displayed according to some prefs (I would do the filtering on the list of objects you pass to the constructor).
Something like that:

public class DbAdapter extends ArrayAdapter<Db> {
    private SharedPreferences preferences;
    int resource;
    String response;
    Context context;
    //Initialize adapter
    public DbAdapter(Context context, int resource, List<Database> items) {
        super(context, resource);
        this.preferences = PreferenceManager.getDefaultSharedPreferences(context);
        filter(items);
        this.resource=resource;
    }

    private final void filter(final List<Database> input) {
        final String pref = this.preferences.getString("some_key", "");
        for (Database db : input) {
            if (!pref.contains(db.dbid + ",")) {
                this.add(db);
            } 
        }
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        LinearLayout DbView;
        //Get the current Database object
        Database db = this.getItem(position);
// ...

This assumes that the preference “some_key” contains a comma separated list of dbId (like 1,5,12,)

NB not tested