Problems with cl_gui_textedit->set_focus

I tried to set focus on my cl_gui_textedit control programmatically in pbo of my dynpro.

But it doesn't work.

Here's my code.

CALL METHOD editor1->set_readonly_mode
   EXPORTING readonly_mode = cl_gui_textedit=>false.

CALL METHOD editor1->set_focus
   EXPORTING
     control = editor1.

CALL METHOD cl_gui_cfw=>flush.

CALL METHOD editor->SET_SELECTION_POS_IN_LINE
 EXPORTING pos = 5
           line = 1.

I almost tried everything.