Android – checkboxpreference dependency not found error

I have this Check@R_ 923_ 2419@Preference

Check@R_923_2419@Preference sendToEmailPref = new Check@R_923_2419@Preference(this);
sendToEmailPref.setTitle("Send To Email");
sendToEmailPref.setDependency("emailList");

I want to set its dependency on a key "emaillist", a custom build preference that stores email recipients as strings

However, I received this error

Caused by: java.lang.IllegalStateException: Dependency not found.....

resolvent:

After calling addpreference, you should call setdependency, which is very useful to me!