clickButton in extendsFragment

Help please, what is this error?

E/AndroidRuntime: FATAL EXCEPTION: main Process: ..., PID: 15686 java.lang.IllegalStateException: Could not find method calculate (MainActivity)(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatButton with id 'button' at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.resolveMethod(AppCompatViewInflater.java:327) at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:284) at android.view.View.performClick(View.java:5697) at android.widget.TextView.performClick(TextView.java:10815) at android.view.View$PerformClick.run(View.java:22526) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:158) at android.app.ActivityThread.main(ActivityThread.java:7229) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) 

CalculateActivity.Java

 package ...; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.EditText; import android.widget.TextView; public class CalculatorActivity extends Fragment { TextView calculateTextView; EditText sumEditText; EditText monthEditText; // Integer sum; // Integer months; // Integer percent; @Nullable @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.calculator_main, container, false); // sumEditText = (EditText) getView().findViewById(R.id.sumEditText); // monthEditText = (EditText) getView().findViewById(R.id.monthEditText); // calculateTextView = (TextView) getView().findViewById(R.id.calculateTextView); return view; //inflater.inflate(R.layout.calculator_main, container, false); } //----------------------------------------------------------------------------------------------// //----------------------------------------------------------------------------------------------// @Override public void onViewCreated(View view, Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); getActivity().setTitle("CrCal"); } //----------------------------------------------------------------------------------------------// }