I have written many posts previously on Timers in Oracle Forms like 

and 

, but in this post I am simply describing to how to create a timer, stop a timer, re-start a timer and deleting a timer.

 

The following is the screen shot for this example showing a progress bar based on a display item:

 

 

You can also download this form from the following link

 

Create a display item with the following properties:

 

Name: Prgbar

Width: 5

Bevel: Plain

Background Color: blue

 

Write the following code for the "Create Timer" button:

When-Button-Pressed trigger

Declare

v_timer timer;

Begin

-- find timer first if already exists.

v_timer := find_timer('PrgBarTmr');

if id_null(v_timer) then

-- Creating timer for one second... one second = 1000 millisecond

v_timer := Create_Timer('PrgBarTmr', 1000, Repeat);

else

message('already exists.');

end if;

-- will handle this timer in form level when-timer-expired trigger

End;

Write the following code for the "Stop Timer" buton:

When-Button-Pressed trigger

Declare

v_timer timer;

Begin

-- find the timer first

v_timer := find_timer('PrgBarTmr');

if not id_null(v_timer) then

-- this will stop the timer after one millisecond

Set_Timer(v_timer, 1, No_Repeat);

end if;

-- will handle this timer in form level when-timer-expired trigger

End;

Write the following code for the "Re-Start Timer" buton:

When-Button-Pressed trigger

Declare

v_timer timer;

Begin

-- find the timer first

v_timer := find_timer('prgbartmr');

if not id_null(v_timer) then

-- this will re-start the timer after one second

Set_Timer(v_timer, 1000, Repeat);

else

v_timer := create_timer('prgbartmr',1000, Repeat);

end if;

-- will handle this timer in form level when-timer-expired trigger

End;

Write the following code for the "Delete Timer" buton:

When-Button-Pressed trigger

Declare

v_timer timer;

Begin

-- find the timer first

v_timer := find_timer('PrgBarTmr');

if not id_null(v_timer) then

-- this will delete the timer

Delete_Timer(v_timer);

end if;

End;

Then finally write the code for When-Timer-Expired trigger at form level to handle the timer and to do specific task:

When-Timer-Expired trigger

Declare

v_timer_name varchar2(30);

v_width number;

Begin

-- get the timer name first.. to know which timer has expired.. if multiple timer are running

  v_timer_name := get_application_property(timer_name);

  -- check if the same timer with capital letters

  if v_timer_name = 'PRGBARTMR' then

    v_width := get_item_property('blKtmr.prgbar', width);

    if v_width < 100 then

       v_width := v_width + 5;

    else

       v_width := 0;

    end if;

    set_item_property('blktmr.prgbar', width, v_width);

end if;

-- will handle this timer in form level when-timer-expired trigger

End;