Conditional Rendering

You can use the display attribute to hide/show fields. display will accept either a function or a string and you have access to the field and the model. A string should evaluate true and a function should return true when the field should display.

Asynchronous displays are currently not supported. However there would be ways around this should you need it. Just get creative :)

Using a string expression

{
    key: 'displayMyField',
    type: 'input'
},
{
    key: 'myField',
    type: 'input',
    display: 'model.displayMyField === "yes"'
}

The above example will only display the myField field when the user has written yes in the first field.

Using a function

{
    key: 'displayMyField',
    type: 'input'
},
{
    key: 'myField',
    type: 'input',
    display: function(field, model){
        return model.displayMyField === 'yes';
    }
}

Validation and Conditional Rendering

Sometimes you may require a field to be required or have some sort of validation only when it is displayed. Just go about your validation as normal and Formly will handle the rest.