How to cancel or reject user dialog in onCreate method?

I created a custom dialog MyCustomDialogthat extends Dialog. I create and display my own dialog box as follows:

new MyCustomDialog(myContext).show();

I override the method Dialog.onCreate(Bundle savedInstanceState)to complete my initialization. I also check this method to see if a condition is met, and if not, I would like to reject / cancel my dialog. I tried to call methods cancel()and dismiss()in my conversations onCreate(Bundle savedInstanceState)and onStart(), but it has no effect.

Does anyone know how to cancel or reject a dialog (from a dialog box) before displaying it?