Use text from a text item or string/number from variable in if statement

Setup, Configuration and Use Scripts & Rules
1

I have an old HDTV controlled by an Arduino. The Arduino knows if the state of the TV is “ON” or “OFF”. I’ve been trying to use rules to set a switch on or off by what is received from the Arduino. It’s not working. I’ve tried integers < and >, string ==, you name it.

Right now my rule is:

rule "television"
when 
  Item televisionpower changed
then
  var result = sendHttpGetRequest("URL FOR ARDUINO")  <<--- gets "ON" or "OFF" from Arduino
  tvstatus.postUpdate(result)  <<-- displays ON or OFF on the openhab menu so know it's working to here
  if (tvstatus.state == "ON") television.state = ON  <<-- I've tried tvstatus.state, integer, < >, result ==...lots of stuff
  else television.state = OFF
end

any ideas?

2

In order to set the state of an item you have to use the postUpdate action. Either;

postUpdate(television, ON)

or

television.postUpdate(ON)

Either should work.

3

First, why don’t you use the http binding to get the state from arduino, since you defined an item already?

Second, if you try to compare a string, you have to use a string on both sides of equality sign, so try out
if (tvstatus.state.toString == "ON")
Just as well you could compare states, but states aren’t strings, so you would have to write
if (tvstatus.state == ON) without quotations around the ON. Surely it depends upon your Item Definition (string? switch?) if the state comparison would be successful.

4

I just tried both of those.

if (tvstatus.state.toString == “ON”)

and

if (result == “ON”)

I’m either doing some way wrong or stupid, or comparing to strings to make decisions is not possible

5

it is definitely possible :slightly_smiling:
Could you please make a log what result really does contain?
logInfo("mylog","Result is {}",result) should do it, you will find the log in ./log/openhab.log