Checkbox property for indeterminate state.


I have to write JavaScript expression in order to implement indeterminate checkboxes.  I think it is very useful the indeterminate state is controllable by an expression of its property.

And the indeterminate checkbox styles for Silk UI web template supported by OutSystems are also expected.

Created on 13 Aug 2018
Comments (11)

"Indetermined" is not a supported value by the OutSystems Boolean data type and changing that would be a huge breaking change. The alternative would be to make a new data type for this, meaning that developers would need to convert between the new data type and Boolean whenever the two data types need to interface, and the conversion could not be done automatically because you would need to decide on a case-by-case basis how to handle "indeterminate". Not saying this wouldn't be useful, but it's a LOT of pain for the entire community.


A new data type? Why?
"indeterminate" is just an additional property of checkbox.


Changed the category to Components

Yes, I am aware that it exists as an HTML thing.

How do you SET or GET the value? OutSystems doesn't have a "NullBoolean" or an "indeterminate" value for booleans. How do you bind this to an OutSystems datatype since there is no datatype for "true/false/unknown"? No user inputs appear in OutSystes that cannot be represented as data because they all get bound to a variable.


I expect an additional property for "indeterminate" like "Visible" or "Enabled".   They are independent from "Variable" property.  We have responsibility for the consistency between our logics/data and these properties.

So how do you read the value from it?

You don't read the properties (except ID and Valid and ValidationMessage) of widgets at runtime. You read their VALUES from the bound variables, and the value of the checkbox is currently bound to a Boolean variable.

Sure, the PROPERTY can say "this checkbox allows indeterminate". How do you read that value without a new datatype that supports true/false/indeterminate?


I need to set "indeterminate" property but don't need to get value of the property.  The property defines how-to-look only.  Like "Visible" and "Enabled" properties.

Currently I use an expression with script to obtain "indeterminate" looks like below.
It would be useful that OutSystems managed script of checkbox widget includes like this.

OK, so basically you have a use case (needing to make an indeterminate checkbox without actually needing to know its value) that is actually pretty unusual. Most other projects, if they put a checkbox on the screen, they need to know the value. It only works for you because of your particular use case. but your implementation (not needing data) doesn't work for many people.


My idea is based on that "indeterminate" is one of the appearance properties like "Visible" and "Enabled" and they are independent from checkboxes value.
However no one likes the idea.  My opinion seems to be unusual.

Thank you for the discussion, Justin.

Changed the category to Frontend