자바 graphics사용으로 그림

package com.example.emt00.myapplication;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

class MyView extends View {
    public MyView(Context context) {
        super(context);
        setBackgroundColor(Color.BLUE);
    }
    @Override
    protected void onDraw(Canvas canvas) {
        Paint paint = new Paint();
        paint.setColor(Color.YELLOW);
        paint.setStrokeWidth(20);
        canvas.drawLine(100,100,700,100,paint);
        canvas.drawRect(100,300,700,700,paint);
        canvas.drawCircle(300,1200,200,paint);
        paint.setTextSize(80);
        canvas.drawText("This is a test.",100,900,paint);
    }
}



public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        MyView w = new MyView(this);
        setContentView(w);
    }
}