Oracle Forms: Dynamic Change in mode of buttons according to certain events

Example


Create Block Named as BLK_BUTTONS
Create following Buttons in BLK_BUTTONS
PB_ENTER_QUERY
PB_EXECUTE_QUERY 
PB_CANCEL_QUERY
PB_SAVE
PB_DELETE
PB_ADD
PB_CLEAR
PB_SCROLL_UP
PB_SCROLL_DOWN 
PB_NEXT_RECORD 
PB_PREVIOUS_RECORD 
PB_PREVIOUS_SCREEN 
PB_NEXT_SCREEN 
PB_EXIT



Form-Level:
UserDefined-Trigger:
  if :system.mode in ('ENTER-QUERY') then
  disable all buttons except execute query, cancel query and exit form
  else
  enable all buttons except cancel query

  if :system.trigger_record = '1' then
  disable previous record, first record 
  enable next record, last record

  if :system.last_record = 'TRUE' then
  disable next record, last record
  enable previous record, first record

WHEN-NEW-RECORD-INSTANCE
  execute_trigger('UserDefined-Trigger');
  
  
-----------------------------------------------------------------------------------------
-- run toolref button commands
  if upper(substr(:system.trigger_item,1,9)) = 'BLK_BUTTONS' then
    if :system.trigger_item = 'BLK_BUTTONS.PB_ENTER_QUERY' then
      do_key('enter_query');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_EXECUTE_QUERY' then
      do_key('execute_query');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_CANCEL_QUERY' then
      do_key('exit_form');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_SAVE' then
      do_key('commit_form');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_DELETE' then
      do_key('delete_record');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_ADD' then
      do_key('create_record');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_CLEAR' then
      do_key('clear_form');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_SCROLL_UP' then
      do_key('scroll_up');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_SCROLL_DOWN' then
      do_key('scroll_down');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_NEXT_RECORD' then
      do_key('down');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_PREVIOUS_RECORD' then
      do_key('up');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_PREVIOUS_SCREEN' then
      do_key('previous_block');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_NEXT_SCREEN' then
      do_key('next_block');
    elsif :system.trigger_item = 'BLK_BUTTONS.PB_EXIT' then
      do_key('exit_form');
    end if;

  end if;  -- BLK_BUTTONS commands