Run UserControl code in backcolorchanged event C#

Question

i want to execute a piece of code when a labels backcolor is changed..

following is the code

private void lbl_ps_BackColorChanged(object sender, EventArgs e)
    {
        if (lbl_ps.BackColor == Color.Green)
       {
            menu_ctrl.setup_array = str_array;
            indx = 0;
        }
    }

here 'menu_ctrl' is a usercontrol where this setup_array consists of following code

public string[] setup_array
    {
        get
        {
            return list_array;
        }

        set
        {
            list_array = value;
            setup_list(value);
        }
    }

private void setup_list(string[] list_item)
    {
        //this.Width = 266;
        this.Height = 181;
        for (int i = 0; i < n; i++)
        {
            this.Controls.Remove(labels[i]);
        }
        label1.Visible = false;
        this.BorderStyle = BorderStyle.None;
        indx_abs = 0; indx_rel = 0;
        n = list_item.Length;

        Array.Resize(ref labels, n);

        for (int i = 0; i < n; i++)
        {
            labels[i] = new CustomText();
            labels[i].Left = 20;
            labels[i].Top = ((30) * i)+1;
            labels[i].IsSelected = false;
            this.Controls.Add(labels[i]);
            labels[i].Text = list_item[i];
        }

        labels[indx_abs].IsSelected = true;
    }

but the code wont execute....it works fine if i call this code from a button click event.. but it wont execute in backcolorchange event

any help?

EDIT:i tried break point and i got this error in the first for loop in setup_list function

Cross-thread operation not valid: Control 'CustomText' accessed from a thread other than the thread it was created on.

the error was caught deep inside a reference dll i've been using. btw a function in this dll is raising this colorchanged event

Answer 1

thanks to @Nati Dobkin!!

i was able to identify the the code trigger was being created on a new thread.. and found this on the internet to force run a code in main thread.

this.Invoke(new MethodInvoker(() => 
           { 
                //run your code here
           }));