android call,msg,email

package com.example.hstu.callmsgemail;

import android.content.Intent;
import android.net.Uri;
import android.provider.Telephony;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    private Button email,msg,call;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        email = (Button)findViewById(R.id.emailID);
        msg = (Button)findViewById(R.id.msgID);
        email = (Button)findViewById(R.id.callID);

        call.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String phone = "01791810207";
                Intent intent = new Intent(Intent.ACTION_DIAL, Uri.fromParts("tel",phone,null));
                startActivities(intent);
            }
        });
    }
}