Visible If not working if value is [0]

[AleksaDursun]

When my selectField value is 0 the schema does not render the fields that have visibleIf: {selectField: [0]}.
This is the code in my schema.
{ type: 'array', title: 'Columns', items: { type: 'object', properties: { color: { type: 'string', description: 'Color', widget: 'color-picker', } }, }, visibleIf: { selectField: [0] }, }

[daniele-pecora]

A working example on Stackblitz (click) for your schema:

{
  "type": "object",
  "properties": {
    "selectField": {
      "type": "string",
      "widget": "select",
      "oneOf": [
        {
          "enum": ["0"],
          "description": "Zero"
        },
        {
          "enum": ["1"],
          "description": "One"
        }
      ]
    },
    "columns": {
      "type": "array",
      "title": "Columns",
      "items": {
        "type": "object",
        "properties": {
          "color": {
            "type": "string",
            "description": "Color",
            "widget": "color-picker"
          }
        }
      },
      "visibleIf": {
        "selectField": [0]
      }
    }
  }
}

@AleksaDursun would you take a look on it?

[AleksaDursun]

That is the workaround I found as well, but the issue still persists. If the value is equal to 0 (number zero) it does not work.

[KBroichhausen]

Got the same problem.
As far as I can tell it's related to this line:

ngx-schema-form/projects/schema-form/src/lib/model/formproperty.ts

Line 252 in f80c7a5

valid = !!value ? `${expString}` === `${value}` : false;

The truth value of variable value is false if it is equal to the number 0 and double negation still makes it false. This is probably to check if there is no null or undefined in the variable value but this also makes the values NaN, number 0, boolean false and empty string '' to not pass this check.

My workaround is to use "$EXP$ target.value == 0"