Handling events across different classes using C# - wpf

Question

I have a property defined in Class A. When the property is changed then i need to raise an event. Another class B should respond to this event and do something. I have done something like this:
Code:
Class A{
string variable = "test";
public delegate void EventHandler(object sender, EventArgs args);
public static event EventHandler ThrowAddEvent = delegate { };
public static event EventHandler ThrowRemoveEvent = delegate { };
public String Name { get; set; }
public int Select { get; set; }
public Window Formref1 { get; set; }
public bool IsSelected
{
get { return IsSlctd; }
set
{
IsSlctd = value;
if (value)
{
ThrowAddEvent(this, new EventArgs());
}
else
{
ThrowRemoveEvent(this, new EventArgs());
}
}
}
}
Another class which is responding to this event is defined as follows:
Class B{
public B(ParsedResult _result)
{
InitializeComponent();
if (_result != null)
{
this.Result = _result;
PopulateColumns1();
DataGrid1.Items.Clear();
DataGrid1.ItemsSource = Populatevariables();
}
}
public void PopulateColumns1()
{
DataGridTextColumn Colvar = new DataGridTextColumn();
Colvar.Header = "Variables";
Colvar.Binding = new Binding("Name");
DataGrid1.Columns.Add(Colvar);
DataGridTemplateColumn Col = new DataGridTemplateColumn();
Col.Header = "Select";
DataTemplate dd = new DataTemplate();
FrameworkElementFactory FF = new FrameworkElementFactory(typeof(CheckBox));
FF.SetBinding(CheckBox.BindingGroupProperty, new Binding("Select"));
FF.SetBinding(CheckBox.IsCheckedProperty, new Binding("IsSelected") { UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
FF.SetValue(FrameworkElement.HorizontalAlignmentProperty, HorizontalAlignment.Center);
dd.VisualTree = FF;
Col.CellTemplate = dd;
DataGrid1.Columns.Add(Col);
}
private List<A> PopulateVariables()
{
CheckBox cb = new CheckBox();
List<A> CharList = new List<A>();
Result.GetCharacteristicList.MoveNext();
IEnumerator<A2LCharacteristic> enumeratorlist = Result.GetCharacteristicList;
for (int i = 0; enumeratorlist.MoveNext(); i++)
{
CharList.Add(new A() { Name = enumeratorlist.Current.Name, Select = i, Formref1 = this});
}
enumeratorlist.Reset();
return CharList;
}
private void OKBtn_Click(object sender, RoutedEventArgs e)
{
A Instance_A = new A();
Instance_A.ThrowAddEvent += (sender1, args) => { Addvrbl(Instance_A.variable); };
Instance_A.ThrowRemoveEvent += (sender2, args) => { RmvVrbl(Instance_A.variable); };
this.Close();
}
public void Addvrbl(string vrbl)
{
if (!(vrbllist.Contains(vrbl)))
{
vrbllist.Add(vrbl);
}
}
public void RmvVrbl(string vrbl)
{
if ((vrbllist.Contains(vrbl)))
{
vrbllist.Remove(vrbl);
}
}
}
The problem is it is not going inside the method "AddVrbl" and "RmvVrbl". I have used the solution from here. Please help.

Answer 1

OK, instead of subscribing to the event of a new instance of A,which will never get triggered/published. When you initializing CharList, you have to subscribe to the event of each A item.
Something like:
for (int i = 0; enumeratorlist.MoveNext(); i++)
{
var obja=new A() { Name = enumeratorlist.Current.Name, Select = i, Formref1 = this};
obja.ThrowAddEvent += ...
obja.ThrowRemoveEvent += ...
CharList.Add(obja);
}
PS: Make sure you un-subscribe these events before removing an item from your CharList.