Default value for the ModelWrapper field method

[svedie]

When I define a ModelWrapper in the ViewModel:

ModelWrapper<MyObject> wrapper = new ModelWrapper<>();

all values of MyObject are initialized with null.

Now, when I use the wrapper to retreive the values and they are null, an NullPointerException is thrown.

This definition of an observable list property:

ObservableList<String> numberProperty() {
   return wrapper.field("number", MyObject::getNummer, MyObject::setNummer);
}

throws an NullPointerException if I use it to initialize an ComboBox or an ListView.

It would be helpfull, if one could define an default value in the ModelWrapper for the getter method. If there is no default value is defined, then the behavior is as now implemented.

[manuel-mauky]

Hi, this is already possible. There are overloaded field methods that are taking an additional argument for the default value. See this example:

public StringProperty nameProperty() {
    return wrapper.field("name", MyObject::getName, MyObject:setName, "default value here");
}

For your example with an observable list it would be:

ObservableList<String> numberProperty() {
   return wrapper.field("number", MyObject::getNummer, MyObject::setNummer, new ArrayList<>());
}

[svedie]

Thanks!

I missed this one method :(