form validation using Rx

 nameET=findViewById(R.id.nameET);
        phoneET=findViewById(R.id.phoneET);
        submitBTN=findViewById(R.id.submitBTN);
       Observable<CharSequence> nameObservable= RxTextView.textChanges(nameET).skip(1)
               .map(name->name.toString());
       Observable<CharSequence> phoneObservable= RxTextView.textChanges(phoneET).skip(1)
               .map(phone->phone.toString());
        Observable.combineLatest(nameObservable,phoneObservable,(name,phone)->{
            return isValidForm(name.toString(),phone.toString());

        }).subscribeOn(Schedulers.io())
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe(result-> {
            if(result){
                submitBTN.setEnabled(true);
        }
            else{
                submitBTN.setEnabled(false);
            }
    });

    public boolean isValidForm(String name, String phone) {
        boolean validName = !name.isEmpty();

        if (!validName) {
            nameET.setError("Please enter valid name");
        }

        boolean validPhone =!phone.isEmpty();
        boolean validNumber=(phone.length()>10);
        if (!validPhone) {
            phoneET.setError("Incorrect phone number");
        }
        else if(!validNumber){
            phoneET.setError("phone number must be  11 charecter");
        }

        return validName && validPhone && validNumber;
    }