Multiple conditions in triggers and trigger on a question

[andrewtelnov]

It is time to re-work the current trigger mechanism in the library. There are several limitation at the current moment.
At first, there is no way to have a complex condition in the trigger. You may check only one question value.
At second, sometimes, it is more convenient to have the visible trigger on the question/page level: make the question/page visible if: [Boolean expression].

The following tasks has to be implemented:

1. Create a Boolean Expression parser to convert the expression into “Boolean” Graph/Tree. Example of expression: {age} >= 21 and ({smoke} == ‘no’ or {beerlover} == ‘no’)
2. Implement a runner. It will run through this “Boolean” tree, using the question values as variables to get the Boolean result (true or false).
3. Replace the current “name”, “operator” and “value” attributes with a string “condition” attribute, for example name: “age”, operator: “greaterorequal”, value: “21” will become, condition: “{age} >= 21”. Make sure, the old attributes will continue to work (convert them on the fly).
4. Create a new attribute in a question “visibleIf” with the type of the boolean expression (string).
5. Create a visual editor for editing Boolean Expression.

[andrewtelnov]

visibleIf: string attribute into page and question objects is added.
The functional can be tested now. I am starting to work on visual editor.

[ItsJoeTurner]

How can I test this function? This is pretty key for me using this. Great stuff btw.

[andrewtelnov]

I do not publish a new version yet. However, you may follow the instruction (readme.cmd) and build the library from sources. You will have a new property: visibleIf.

[andrewtelnov]

I am using {youquestionName} for question names in expressions.

[thegovind]

@andrewtelnov So I'm guessing this is incomplete?:

Create a Boolean Expression parser to convert the expression into “Boolean” Graph/Tree. Example of expression: {age} >= 21 and ({smoke} == ‘no’ or {beerlover} == ‘no’)

[andrewtelnov]

@git2g Sorry, I did not get the question :-(
{age} >= 21 and ({smoke} == ‘no’ or {beerlover} == ‘no’)
The tree is:

and

1. {age} >= 21
2. or
   2.1) {smoke} == ‘no’
   2.2) {beerlover} == ‘no’

It looks fine to me.

[varunkumar]

It would be great to have this expression parser for setValue trigger as well.

[andrewtelnov]

Here is the example of using contains: https://plnkr.co/edit/vNDIFk?p=preview Thank you, Andrew

…

On Wed, Aug 9, 2017 at 11:01 PM, Gary Bond ***@***.***> wrote: Does the visibleIf conditional evaluation work where the operator is 'contains'? I need to make a question visible if one particular option is selected on a previous multi-select question. I've set it up using the triggers, but I wondered if the expression could be configured at the question rather than at survey level. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#60 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFZKRNTQ6wQTnR0gw9UJwMEENC_Zex8Vks5sWhAqgaJpZM4Js9Pj> .