code: def open_fileswitcher_dlg(self):
          
          if not self.tabs.count():
              return
          if self.fileswitcher_dlg is not None and \
            self.fileswitcher_dlg.is_visible:
              self.fileswitcher_dlg.hide()
              self.fileswitcher_dlg.is_visible = False
              return
          self.fileswitcher_dlg = FileSwitcher(self, self, self.tabs, self.data,
                                               ima.icon('TextFileIcon'))
          self.fileswitcher_dlg.sig_goto_file.connect(self.set_stack_index)
          self.fileswitcher_dlg.show()
          self.fileswitcher_dlg.is_visible = True
docs: Open file list management dialog box