다른 클래스에 MainActivity 클래스 전달

1. MainActivity.java

 

package ...
 
import android.app.Activity;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.Toast;
 
public class MainActivity extends AppCompatActivity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
 
        Person person01 = new Person("철수", this);
        person01.walk(10);
 
        Person person02 = new Person("영희", this);
        person02.walk(10);
 
        Person person03 = new Person("민희", this);
        person03.walk(10);
 
        Person person04 = person03;
        person04.walk(10);
 
        String outName = person04.name;
        System.out.println("person04.name : " + outName);
        person03.name = "민정";
 
        System.out.println("person04.name : " + outName);
 
 
        Leg outLeg = person04.leg;
        System.out.println("person04.leg : " + outLeg.left);
        person03.leg.left = "왼쪽 다리";
 
        System.out.println("person04.leg : " + outLeg.left);
 
        Leg outLeg2 = person04.getLeg();
        System.out.println("person04.leg : " + outLeg2.right);
        person03.leg.right = "오른쪽 다리";
 
        System.out.println("person04.leg : " + outLeg2.right);
    }
}
 
class Person {
    String name;
    Leg leg = new Leg();
 
    Activity activity;      //*
 
    public Person() {       // Default Constructor
 
    }
 
    public Person(String inName, MainActivity inActivity) {     //*
        name = inName;
        activity = inActivity;          //*
    }
 
 
    public void walk(int speed) {
        Toast.makeText(activity.getApplicationContext(), name + "이(가) " + speed + "km 속도로 걸어갑니다.", Toast.LENGTH_LONG).show(); //*
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public void setLeg(Leg leg) {
        this.leg = leg;
    }
 
    public void run(int speed) {
        System.out.println(name + "이(가) " + speed + "km 속도로 뛰어갑니다.");
    }
 
    public Leg getLeg() {
        return leg;
    }
}
 
class Leg {
    String left = "왼쪽";
    String right = "오른쪽";
}