Javafx：从TableCell获取属性

Question

I want to get a property from a model in my TableCell, so I can maipulate the cell depending on that property lets se the following example:

I have a model like:

public class Model {

    private CustomProperty<Integer> appleCount;
    private CustomProperty<Integer> peachCount;

    public Model(Integer appleCount, Integer peachCount) {
        this.appleCount = new CustomIntegerProperty(appleCount);
        this.peachCount = new CustomIntegerProperty(peachCount);
    }

    public CustomProperty<Integer> appleCountProperty() {
        return appleCount;
    }

    public CustomProperty<Integer> peachCountProperty() {
        return peachCount;
    }
}

This model is just a mock of that I have, and I have a few models which have two or more CustomProperty<Integer>

Then I have a few tables that has this Model or a similar class as model of the TableView . I have a custom TableCell with overriden updateItem and there I want to set the cell's text depending on the properties that CustomProperty has for example initialValue, oldValue, etc.Fo example if the initialValue is 0 then set the text empty instead of the 0 that has the cell by default. I have a partial solution for it: creating an interface HasCustomProperty then the Model would implement it, but then there are a few problems:

• I need to add two CustomProperties or a list of them to the interface
• I need to ask somehow in the cell: Are you the appleCount? or Are you the peach cell?

It is sure that in one cell there is only one property, the apple or the peach, so theoretically I should not care about in the cell if I know both of them are CustomIntegerProperties so I know they have initialValue or oldValue so I can set the cell's text depending on it.

I can only get the item, which is a type of Integer, so I don't have the properties of it or is there any way to get the property itself?

A sollution could be to override in every column's cellFactory the updateItem, and there I know for instance this is the appleColumn so get the information from the appleCountProperty, and so on, but this causes a lot of duplicate code if I have to do it in 5-6 places. So I thought I make a custom TableCell and there I manage the text, then I just set for every column that cell for cellFactory() .

Do you have any Idea how can I do it simple without duplicate code?

Answer 1

Based on our discussion - I think the issue you are facing is determining the difference between a user set 0 and an initialized 0 of an IntegerProperty.

Rather than use IntegerProperty which uses int and can't be null - you should use the following in the model:

private ObjectProperty<Integer> appleCountProperty = new SimpleObjectProperty<>();

Then in your table you just bind to it:

@FXML
TableColumn<Model, Integer> appleCountColumn;

//In your initialize

appleCountColumn.setCellValueFactory(data -> data.getValue().appleCountProperty ());

This should give you what you need.