Double click on selected row does not create tree for more than once

See more:

C#

WPF

System only generate treeview for first selected row like this

ProcessName
         Module
            SubModule
         Thread
            SubThread

But I want if user again select a row system generate another tree like this and so on

ProcessName1
         Module
            SubModule
         Thread
            SubThread
ProcessName2
         Module
            SubModule
         Thread
            SubThread 

What I have tried:

I have create a table that has two column one contain name of processes and second contain ID of processes. When user click on any row user create tree for that row in another panel
This is code of event handler for row selected

private void Row_DoubleClick(object sender, MouseButtonEventArgs e)
        {
            DataGridRow row = sender as DataGridRow;
            // Some operations with this row
            if (row != null)
            {
                var item = row.DataContext as Processes;
                if (item != null)
                {
                    int id = item.ID;
                    var subModules = new List<ITreeNode>();
                    var subThreads = new List<ITreeNode>();
                    for (int i = 0; i <= 3; i++)
                    {
                        subThreads.Add(new SubThread { Name = "subthread" + i });
                    }
                    var nodes = new List<ITreeNode>
        {
            new Thread { Name = "Thread ", ChildNodes = subThreads },
            new Module { Name = "Module ", ChildNodes = subModules }
        };
                    var runprocesses = new List<RunProcesses>();
                    Process myProcess = Process.GetProcessById(id);
                    ProcessModule myProcessModule;
                    //Get all the modules associated with 'myProcess".
                    ProcessModuleCollection myProcessModuleCollection = myProcess.Modules;
                    for (int i = 0; i < myProcessModuleCollection.Count; i++)
                    {
                        myProcessModule = myProcessModuleCollection[i];
                        string s = myProcessModule.FileName;
                        if (i == 1)
                        {
                            runprocesses.Add(new RunProcesses { Name = myProcessModule.FileName, ChildNodes = nodes });
                        }

                        subModules.Add(new SubModule { Name = s });
                        //Console.WriteLine("The moduleName is " + myProcessModule.ModuleName);
                    }

                    TreeView.ItemsSource = runprocesses;

                }
            }

This is the code for table

<pre><Grid>
                            <DataGrid Name="dg" AutoGenerateColumns="False"
                  ItemsSource="{Binding Processes}" SelectionMode="Extended" >
                               
                                <DataGrid.Columns>
                                    <DataGridTextColumn  Binding="{Binding ID}" Header="PID" Width="100"  />
                                    <DataGridTextColumn Binding="{Binding ProcessName}" Header="Process" Width="150"  />
                                </DataGrid.Columns>
                            </DataGrid>
                        </Grid>

I don't know what to do. Kindly guide me where I am wrong