147756 - nsIAccessible's accValue returns NS_ERROR_FAILURE

Status: VERIFIED FIXED

(Core :: Disability Access APIs, defect)

Description

[dsirnapalli]

-- Test case attached.
If accValue is not implemented for listbox then it should return
NS_ERROR_NOT_IMPLEMENTED. It should not return NS_ERROR_FAILURE.

Comment 1

[dsirnapalli]

Attachment: Test case to reproduce the bug

Comment 2

[Kyle Yuan]

take it for me...

Comment 3

[Kyle Yuan]

aaron, I found that, we can call
nsCOMPtr<nsIDOMXULMultiSelectControlElement> select(do_QueryInterface
(mDOMNode)); to get a  nsIDOMXULMultiSelectControlElement*, but
nsCOMPtr<nsIDOMXULSelectControlElement> select(do_QueryInterface(mDOMNode)); 
will failed, although nsIDOMXULMultiSelectControlElement inherits from 
nsIDOMXULSelectControlElement.

I'm not sure whether this is a bug of XUL or it should like this.

Comment 4

[Aaron Leventhal]

Attachment: Tells listbox that it supports nsIDOMXULMultiWhateverItIs

Kyle, how's this?

That returns a value if something in the listbox is selected.
It still returns an error if nothing is selected.

Comment 5

[Aaron Leventhal]

Kyle, seeking r= on this as well.

Comment 6

[Kyle Yuan]

1) we should check selectedItem != nsnull, before use it 
http://lxr.mozilla.org/seamonkey/source/accessible/src/xul/nsXULSelectAccessible
.cpp#196

2) there is a similar bug for nsXULComboboxAccessible
http://lxr.mozilla.org/seamonkey/source/xpfe/global/resources/content/bindings/m
enulist.xml#42

3) should we add _retval = NS_LITERAL_STRING(""); at the beginning of 
GetAccValue?

Comment 7

[Aaron Leventhal]

Attachment: Adds Kyle's suggestions

Comment 8

[Kyle Yuan]

Comment on attachment 85788 [details] [diff] [review]
Adds Kyle's suggestions

r=kyle

Comment 9

[Johnny Stenback (:jst)]

Comment on attachment 85788 [details] [diff] [review]
Adds Kyle's suggestions

@@ -190,11 +190,13 @@
   */
 NS_IMETHODIMP nsXULListboxAccessible::GetAccValue(nsAString& _retval)
 {
+  _retval.Assign(NS_LITERAL_STRING(""));

This is just wrong, if you want to empty out the string, then just truncate it,
no need to construct a string wrapper for an empty string just to assign it
into another string. _retval.Truncate(0)!

sr=jst with that change.

Comment 10

[Aaron Leventhal]

fixed

Comment 11

[dsirnapalli]

-- Hi aaron, did you check in the fix.

Comment 12

[Aaron Leventhal]

Yep, that's why I marked it "fixed". Is that crazy or what? :)

Comment 13

[dsirnapalli]

-- no, you usually mention "checked in" after "fixed". I see that for almost all
the bugs you fixed.

Comment 14

[dsirnapalli]

-- I still get NS_ERROR_FAILURE when i run the attached test case. I verified it
on todays trunk build.

Comment 15

[dsirnapalli]

-- hi aaron, it works fine. In Inspect tool it shows right value. Works as
described.

Returns a value if something in the listbox is selected.
It still returns an error if nothing is selected.

Marking the bug back as Fixed.

Comment 16

[dsirnapalli]

-- Verified in todays trunk build. works fine. marking bug as verified.