I'm struggling with bindings of non-string types, ...

# tornadofx

[permalmberg]

I'm struggling with bindings of non-string types, specifically `Int`and Double. I have a base class like this:

abstract class BaseProperty<T> internal constructor(val header: String, protected val key: String, protected val defaultValue: T, protected val comp: Component) : ViewModel() {
    var value: T by property(defaultValue)
    fun valueProperty() = getProperty(BaseProperty<T>::value)

    abstract fun updateValue(v: T)
    abstract fun readValue() : T

    fun init()
    {
        value = readValue()
    }

    init {
        valueProperty().onChange {
            updateValue(value)
        }
    }
}

from which I inherit a more specified "property handler":

class IntProperty(header: String, key: String, defaultValue: Int, c: Component) : BaseProperty<Int>(header, key, defaultValue, c) {
	override fun readValue(): Int {
		return comp.getProperty(key, defaultValue)
	}

	override fun updateValue(v: Int) {
		comp.setProperty(key, v)
	}
}

In my ViewBuilder (part of the ViewModel-layer) I do this:

override fun show(property: IntProperty) {
        property.init()
        with(myForm) {
            field(property.header) {
                textfield {
                    bind(property.valueProperty())
                }
            }
        }
    }

i.e. I bind to a

BaseProperty<Int>::value

. This is working fine as long as only numbers are entered. As soon as a . or other non-numbers are entered an exception is thrown. That is in itself is expected and I need to use a converter for that (I also want to add a validator). This is where I run into problems. The examples in the TFX guide all says to use the format textfield(model.name) { } but I can't get that compile since it can't find an overload that matches - it seems want a Number. Do I have any other option than to use Number instead of Int and Double? My backend is in Java so it has no notion of Number.