Filter Builder. How to detect that the Filter is Cleared or Empty.

[tece321]

I want to detect, from a FilterBuilder object, that it's criteria is in the cleared or not initialized state. How do I do that?

Initially the Filter is cleared with

filterBuilder.clearCriteria();

In some other click handler I want to detect if the Filter Builder is still empty or cleared state.

Do I have to write code

filterBuilder.getCriteria(false)

and then test that the component Criterion has a null value?

Is there not a

filterBuilder.getClearState()

call? True if clear, false if set? Or is this onus on me?

[tece321]

Is there an easier way - an existing method - than this?

AdvancedCriteria crit = filterBuilder.getCriteria();
boolean isCleared = false;
try {
if ( crit.getCriteria()[0] == null ) {
isCleared = true;
}
catch (Exception e) {
isCleared = true;
}

if ( isCleared ) {
do this
}
else {
do that
}

[Isomorphic]

That's not very long (and it's not clear why you have exception handling), but if you want something even shorter, you could use DataSource.compareCriteria() to compare to a known empty criteria.

[tece321]

Agreed. But still think you might add a method to FilterBuilder, when filterBulder.setAllowEmpty(true), that returns a boolean indicating if the builder is in cleared state or not. And I suppose do the correct thing when setAllowEmpty(false).

Experience has shown that checking for null cases is more rigorous between SmartGWT releases by wrapping the check with the exception handler.