tokenize - IOS: Tokenizer on UITextInput is never called -

i have uitextinput implementation 1 small problem seems screwing ability have autocapitalization:

the tokenizer property never gets called (even after calling becomefirstresponder), custom tokenizer never gets instantiated or used.

- (id<uitextinputtokenizer>)tokenizer { nslog(@"%s", __func__); if (tokenizer == nil) {     tokenizer = [mycustomtokenizer alloc] initwithtextinput:self]; } return tokenizer; 

does have idea why happen?

more info may help: uitextinput implementation on subclass of uicollectionview

figured out. returning nil selectedtextrange when should have been returning selection of length 0.