empty_value in custom indicator

[miro1360]

How can I compare empty_value from custom indicator buffer?

I need this: When is in buffer empty_value, I need do something.

I make this comparison in Condition block:

Left side (custom indicator buffer) == Right side (Value: ? (EMPTY_VALUE))
true: open buy
false: open sell

What can I give on place for constant "EMPTY_VALUE" into Right side to comparison?

edit1:
I have modified my custom indicator, now on the place of EMPTY_VALUE in buffer get 0. With 0 it is working.

[fxDreema]

"Condition" will not work this way anymore. I decided to make it in a way to not pass at all if the value of one of it's two sides equals to EMPTY_VALUE. But you can try this block called "Indicator is invisible"