Filling SelectOneChoice From Backingbean (ADF)

One of the things I like about developing with JDeveloper and ADF is that you can do an awful lot by just dragging components and data controls and dropping them into a web form. Configure a few properties to control how the component works and looks, and you're done. But sooner or later you do have to write a little Java code.

So, awhile back I needed to display data in SelectOneChoice component after fetching values from the database in a bean using Application module implementation class.

The following is what I did:

1. In the backingbean, define a variable that will hold the selected Value ( i.e. The value which you will select from the selectOneChoice component ) [e.g public String selectedValue;] and make its setter and getter methods.

2. In the backingbean, define an array of selectItem that will fill the selectOneChoice (e.g. public SelectItem[] elements = null; ) and make its getter and setter method.

3. In the getter method of selectItem, write this code :

1. BindingContainer bindings = getBindings();
2. DCIteratorBinding iterator = (DCIteratorBinding)bindings.get("fetchAllServiceProviderTypesIterator");
3. int length = iterator.getRangeSize() > 0 ? iterator.getRangeSize() : new Long(iterator.getEstimatedRowCount()).intValue();
4. elements = new SelectItem[length];
5. SelectItem item = null;
7. for (int i = 0; i < length; i++) {
8. Row row = iterator.getRowAtRangeIndex(i);
10. if (row != null) {
11. item = new SelectItem();
12. item.setValue(row.getAttribute("code").toString());
13. item.setLabel(row.getAttribute("name").toString());
14. }
15. elements[i] = item;
16. }
17. return elements;

Where : fetchAllServiceProviderTypesIterator is the Iterator which its data will fill the selectOneChoice (You must add this iterator in the pageDef).

Now, your final backingbean should look something like this :

1. public class ServiceProviderBacking {
3. /** An array of selectItem that will fill the ServiceProviderType selectOneChoice */
4. public SelectItem[] elements = null;
6. /** Variable to hold the selected Service Provide Type Value */
7. public String selectedValue;
9. private BindingContainer bindings;
11. public void setElements(SelectItem[] elements) {
12. this.elements = elements;
13. }
15. /**
16. * Populate the selectObeChoice with the ServiceProviderType values
17. *
18. * @return
19. */
20. public SelectItem[] getElements() {
22. BindingContainer bindings = getBindings();
23. DCIteratorBinding iterator = (DCIteratorBinding)bindings.get("fetchAllServiceProviderTypesIterator");
24. int length = iterator.getRangeSize() > 0 ? iterator.getRangeSize() : new Long(iterator.getEstimatedRowCount()).intValue();
25. elements = new SelectItem[length];
26. SelectItem item = null;
28. for (int i = 0; i < length; i++) {
29. Row row = iterator.getRowAtRangeIndex(i);
31. if (row != null) {
32. item = new SelectItem();
33. item.setValue(row.getAttribute("code").toString());
34. item.setLabel(row.getAttribute("name").toString());
35. }
36. elements[i] = item;
37. }
38. return elements;
39. }
41. public void setSelectedValue(String selectedValue) {
42. this.selectedValue = selectedValue;
43. }
45. public String getSelectedValue() {
46. return selectedValue;
47. }
49. /**
50. * Get the page bindings
51. *
52. * @return
53. */
54. public BindingContainer getBindings() {
55. if (this.bindings == null) {
56. FacesContext fc = FacesContext.getCurrentInstance();
57. this.bindings =
58. (BindingContainer)fc.getApplication().evaluateExpressionGet(fc,
59. "#{bindings}",
60. BindingContainer.class);
61. }
62. return this.bindings;
63. }
64. }

4. In your page, drag a selectOneChoice component and set its value to :

#{yourBean.selectedValue}

5. Insert f:selectItems inside the af:selectOneChoice and set its value to:

#{yourBean.elements}

That's all there is to it.

By the way, while what I am showing you DOES work, it may not be the optimal solution - if a more experienced ADF developer wants to chime in with a better way please do.