Im trying to draw either a green or a red circle forever on to the android screen

im trying to make a game that when a user clicks on a green button it disappears but when a user clicks on a red button they loose im having trouble displaying multiple random buttons continuously on forever onto the screen here is my code

package com.Tripps.thesimplegame;

import java.util.Random;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Paint.FontMetrics;
import android.util.AttributeSet;
import android.view.View;

public class DrawingView extends View {
    int mBackgroundColor = 000000;
    String yo = "#";
    Paint paint;
    final float radius = 230f;
    private long lastUpdated = 0;
    private int lastColor = Color.BLACK;

    public DrawingView(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
    }

    public DrawingView(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub
    }

    public DrawingView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        // TODO Auto-generated constructor stub
    }


    @SuppressLint("DrawAllocation")
    @Override
    protected void onDraw(Canvas canvas){

        String str = "Joke of the day";
        super.onDraw(canvas);
        paint = new Paint();
        Random random = new Random();
        Random randomTwo = new Random();

        //Rect ourRect = new Rect();
        Rect topRect = new Rect();
        Rect backGround = new Rect();

        paint.setColor(Color.BLACK);
        backGround.set(0,0,canvas.getWidth(),canvas.getHeight());
        canvas.drawRect(backGround, paint);


        while(System.currentTimeMillis() > lastUpdated + 1000){
            lastColor = random.nextInt(2) == 1 ? Color.RED : Color.GREEN;
            lastUpdated = System.currentTimeMillis();
            paint.setColor(lastColor);
            canvas.drawCircle(random.nextInt((int) (canvas.getWidth()-radius/2)) + radius/2f, random.nextInt((int) (canvas.getHeight()-radius/2)) + radius/2f, radius, paint);
        }
    }
}