How to store List of objects in ViewModel to display them in DataGrid?

February 25, 2014

the task pretty simple , i'm sure absolutely general - need display list of objects in datagrid.

in more details:

i have collection of "consoledata" objects (from trading software). each consoledata has

read-only static fields (ticker)
read-only dinamic fiels update every second (price)
mutable static fields - strategy parameters. numbers static can changed user directly datagrid via command (stop loss)

my implementation:

    public class overviewviewmodel
    {
        public observablecollection<consoledata> datalist { get; set; }

        public overviewviewmodel(iwcfmodel model)
        {
            this.datalist = new observablecollection<consoledata>();
            model.dataarrived += new action<list<consoledata>>(model_dataarrived);
        }

        private void model_dataarrived(list<consoledata> datalist)
        {

            // every time receive fresh table - not changes, entire table
            datalist.clear();
            datalist.foreach(x => datalist.add(x));
        }

    }

}

there several problems implementation:

ui selection lost: when new data arrived datalist cleared - ui selection lost.
perfomance: each datalist.add(x) call "updates" observablecollection , forces ui refresh. want update entire table , after refresh ui. current application takes 15% of cpu

so far know 2 solutions problem:

make consoledata implement inotifypropertychanged, instead of "replacing consoledata" in viewmodel "update consoledata" in viewmodel. think solve problem 1 not problem 2. think it's not "mvvm-complained"...
mvvm approach - create consoledataviewmodel , in overviewviewmodel store instances of consoledataviewmodel instead of consoledata. don't know how implement consoledataviewmodel. can read more that?

which solution should select 1 or 2? read more solution 2? can suggest better solution?

please choose first one:

simple example:

http://www.codeproject.com/kb/wpf/stepbystepguidetomvvm.aspx

more complex one:

http://www.codeproject.com/kb/wpf/mvvmepisode1.aspx

http://www.codeproject.com/kb/wpf/mvvmepisode2.aspx

http://www.codeproject.com/kb/wpf/mvvmepisode3.aspx

http://www.codeproject.com/kb/wpf/mvvmepisode4.aspx

Silverlight > MVVM / ViewModel Pattern with Silverlight