JavaFX binding and null values

Question

I was wondering how to bind values where the source of the bind could be null.

I have a property:

private ObjectProperty operation = new         


        

Answer 1

If a 3rd party library is an option, check out EasyBind. Try something like this:

EasyBind.select(operation)
        .selectObject(Operation::nameProperty)
        .orElse("null");

There's also a JavaFX JIRA issue for the type of functionality provided by EasyBind. If you don't want to use a 3rd party library, try Bindings.select:

Bindings.when(operation.isNotNull())
    .then("null")
    .otherwise(Bindings.select(operation, "name"));

Be aware the null checking in Bindings.select isn't super efficient. There's a JIRA issue for it.

Answer 2

Just in case if somebody using not Java itself but Kotlin. It is a good idea to use wonderful tornadofx library. There you can just use operation.select{it.name}. Although, this feature seems not to be documented yet, so it took some time to discover it.