GWT RadioButton分组

Question

In my application, I have URN-identified data coming in from the server. I'm in the process of abstracting as far as possible so there is very little to no logical code in my views, and I'm using a generic presenter that wraps those views. All widgets have URNs, making it super easy to map incoming data to a specific widget (until now, a 1 to 1 relationship). This has worked well for pretty much every widget, and now I've reached a point where I'm tripped up.

Assume I have (just for simplicity's sake) two RadioButton elements on a view. These buttons belong to a "group" (just by setting their name values to the same thing), but obviously they're 2 distinct elements. I can't map my URN-identified data to a single widget as in every other case because, in this case, it is two widgets.

Here's an example of what I mean:

Utility Company is a ListBox , so just one widget there. I map each item in the list to a specific Enum value.

Utility Rate is a TextBox , so again just one widget to map.

For Energy Usage, they can select to use either an average for the year or input 12 monthly values. I'm stuck here. I can't map to just one of the RadioButton elements, because then I'd need some extra logic in the view to handle the behavior appropriately.

Am I stuck mapping to just one widget and sticking (unwanted) logic in my view to determine what the state of all of the elements should be based on the value that came in for the one widget that is mapped?

How should I handle this case?

Edit (Solution): Following the concepts of jusio's answer, I came up with a workable solution. Because I didn't want to go sticking special case handling through my logic to take care of a non-widget, I created a RadioButtonSet faux widget ( public class RadioButtonSet <T extends Enum<?> & HasDisplayText> extends Widget implements HasValueChangeHandlers<T>, HasValue<T> ), into which I manually pass the radios I intend to group. Having done that, I can get or set its value and have it fire appropriate events when the user changes the selection. Then mapping the collection of radios is no different than doing so for a listbox. Thanks jusio.

Answer 1

I believe in your case you shouldn't treat radio buttons as two separate widgets, basically in your case you can treat the radio button group as combo box, because behavior is almost the same (the only problem is that you have additional master detail). So basically what you will have to do is to wrap real BO objects into some kind of RadioButtonGroupModel, and give it to view, view can take this model and generate radio buttons (with some editors or whatever else). I remember running into this problem when i was extending databinding FW for JFace, and this was the best way I could find to solve this problem.

Answer 2

If I understood correctly the problem, there are 2 possible solutions:

1. • Give each RadioButton a unique URN (ex: oldURN_1 , oldURN_2)
   • When you send data for a URN, disable the other one
2. Keep the same Name for each RadioButton but add a number variable in the data the server sends indicating which radioButton it is supposed to use (ex: 0 for Average and 1 for Monthly)