How do I set a Boolean field with "yes" and "no" values? I have a content type, I'm trying to add a field that's a boolean. I want the options to be yes or no. This is something I thought would be relatively simple however, I keep getting an error message. I've attached 2 screenshots. 1 is the configuration for my boolean. The other is the error message my site gets. Can someone help me. What am I doing wrong?
The Boolean field accept only 0 and 1 as value.
if you want to add allowed values by PHP Code should be:

0|No
1|Yes 


I create a Boolean field on Content type and i set the On value to Yes and
 off Value to No.
As you see In the below screenshot the value of input is 0 for NO and 1 for Yes.