Added files of Alex and fixed the code.

UI/app/src/main/java/com/example/capstone/addDriver.java

@@ -0,0 +1,62 @@
+package com.example.capstone;
+
+import android.app.Dialog;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.widget.EditText;
+
+import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatDialogFragment;
+
+public class addDriver extends AppCompatDialogFragment {
+    private EditText fn, ln, ph, em;
+    private addDriverListener listener;
+    @Override
+    public Dialog onCreateDialog(Bundle savedInstanceState) {
+        AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
+        LayoutInflater inflater = getActivity().getLayoutInflater();
+        View view = inflater.inflate(R.layout.add_driver, null);
+
+        builder.setView(view).setTitle("Add Driver").setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
+            @Override
+            public void onClick(DialogInterface dialog, int which) {
+
+            }
+        })
+        .setPositiveButton("Add", new DialogInterface.OnClickListener() {
+            @Override
+            public void onClick(DialogInterface dialog, int which) {
+                String fns = fn.getText().toString();
+                String lns = ln.getText().toString();
+                String phs = ph.getText().toString();
+                String ems = fn.getText().toString();
+                listener.applyTexts(fns, lns, phs, ems);
+            }
+        });
+
+        fn = view.findViewById(R.id.fname);
+        ln = view.findViewById(R.id.lname);
+        ph = view.findViewById(R.id.phone);
+        em = view.findViewById(R.id.email);
+
+        return builder.create();
+    }
+
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+
+        try {
+            listener = (addDriverListener) context;
+        } catch (ClassCastException e) {
+            throw new ClassCastException(context.toString()+"must implement addDriverListener");
+        }
+    }
+
+    public interface addDriverListener{
+        void applyTexts(String fn, String ln, String ph, String em);
+    }
+}