Monodroid - Passing Data To Listview According To Gref Limit

C#, Mono for Android. I need to output a large portion of combined data into ListView. To achieve this, I use the following obvious approach with Adapter: class ItemInfo { publ

Solution 1:

In my project i had the same problem.

1. ItemInfo is managed object, so you don't need to do anything with it, GC collects when it will be necessary.
2. ListView does not load view for each list item at once, so you can control number of created views and dispose them.

Here is my solution

I have removed some unnecessary overrides from BaseAdapter so don't be afraid if it ask you to implement them.

classCustomViewAdapter : BaseAdapter<ItemInfo>
    {
    privatereadonly Context _context;
    private IList<ItemInfo> _items;
    privatereadonly IList<View> _views = new List<View>();

    publicCustomViewAdapter(IntPtr handle)
        : base(handle)
    {
    }

    publicCustomViewAdapter (Context context, IList<ItemInfo> objects)
    {
        _context = context;
        _items = objects;
    }

    privatevoidClearViews()
    {
        foreach (var view in _views)
        {
            view.Dispose();
        }
        _views.Clear();
    }

    publicoverride View GetView(int position, View convertView, ViewGroup parent)
    {
        var inflater = LayoutInflater.From(_context);
        var row = convertView ?? inflater.Inflate(Resource.Layout.ListItemView, parent, false);
        /// set view dataif(!_views.Contains(row))
            _views.Add(row);
        return row;
    }

    publicoverrideint Count
    {
        get { return _items == null ? 0 : _items.Count; }
    }

    publicoverridevoidDispose()
    {
        ClearViews();
        base.Dispose();
    }
} 

Usage example

[Activity]
publicclassMessagesActivity : Activity
{
    private CustomViewAdapter _adapter;

    protectedoverridevoidOnCreate(Android.OS.Bundle savedInstanceState)
    {
       base.OnCreate(savedInstanceState);
       SetContentView(Resource.Layout.ListView);
       _adapter=new CustomViewAdapter(this,Enumerable.Empty<ItemInfo>);
       FindViewById<ListView>(Resource.Id.list).Adapter=_adapter;
    }

    publicoverridevoidFinish()
    {
        base.Finish();
        if(_adapter!=null)
           _adapter.Dispose();
        _adapter=null;
    }
}

Solution 2:

Answer found. I've inherited my ItemInfo class from Java.Lang.Object explicitly and now can call Dispose() when object is no longer needed. This kills leaking GREFs.