// Top of ur .cs file
...
using AndroidCtrl;
using AndroidCtrlUI.Explorer;
using AndroidCtrlUI.Explorer.Actions.Windows;
...


// OnDrop handler
public void OnDrop(object sender, DragEventArgs e)
{
    // Drop destination path
    string dest = "C:\\";

    // Here we check if the drop element includes a DataObject
    if (e.Data is DataObject d && d.ContainsFileDropList())
    {
        // Extract the sender
        string s = d.GetText(TextDataFormat.Text);

        // Check if the sender is the android viewmodel.
        if (s == "android" && d.GetDataPresent(typeof(DeviceInfo)))
        {
            // Now init the copy process
            Copy copy = new Copy(this, (DeviceInfo)d.GetData(typeof(DeviceInfo)), s, "local", dest, d.GetFileDropList(), e.Effects == DragDropEffects.Move);

            // (optional) Here you can define a callback which is raised if the copy window is closed.
            copy.Closed += DropCallback;

            // Show the copy window
            copy.Show();
        }

        // If the sender isn't the android viewmodel, your OnDrop code will be executed.
        else
        {
             // Your OnDrop code goes here.
        }
    }
    e.Handled = true;
}

// (optional) Callback after the window is closed.
private void DropCallback(object sender, EventArgs e)
{
    // Do a refresh or something.
}