Can't Input when focus a text field

i have a chat field. but while i write something i cannot push any button.
i need to make “write and push enter to send message”.
for i send the message , i need to lost the focus at the textfield

edit :
i mean i dont get any button when i focused on a textfield

Maybe:

Input.eatKeyPressOnTextFieldFocus = false;

http://unity3d.qatohost.com/questions/149483/textfield-eats-all-keys-as-of-340.html

If you’ve started with the example Network Chat.JS, it’s a bit bad that way but is pretty easy to modify for any particular requirement. Hard to say without code, but basically you need to set the initial focus and then keep it on that field, even when new messages come in.