Binding nested field/property to component

Vaadin 6 / 7 / 8 Framework Data Binding
1

Hi,

This is a simple requirement but unfortunately i could not find an answer yet.

class A {
 B b = new B();
}

class B {
 int value;
}

A a = new A();
TextField tf = new TextField(new MethodProperty(a, "b.value"));

Why can i not bind a nested field (b.value in this case) to component? What do i have to do?

2

Take a look at the
POJO Container
 and its PojoItemProperty (IIRC), which might solve your problem.

In the future, such functionality might also get implemented in BeanItem.

3

Hi Henri,

sorry for hooking in but is there a way to notify the table in case the POJO item properties change? In terms of having a collection of users, adding these to the POJOContainer and changin one of these items? I could not figure out any way how to reflect these changes to the UI but I’m pretty sure there must be a way to do so - can u help please?

Thanx, Florian!

4

If you change the values through the Property of the Item (Vaadin data model), they should be automatically reflected on the UI.

If you change the POJOs directly, without Beans Binding (JSR 295; no support for this in Vaadin standard containers), it is not possible for Vaadin to be automatically informed of the changes. Some Vaadin containers might provide a way to explicitly refresh a part or all of the data from the underlying POJOs, but most of the standard ones don’t. Alternatively, you could try to see if setting the same container again for the table helps to explicitly make it refresh (all of) its contents - this might or might not be a solution in your case.