how to generate ten random number [on hold]

this is my imageview list

 public ImageView[] IMGS = { iv1, iv2, iv3, iv4, iv5, iv6,iv7,iv8,iv9,iv10,iv11,iv12,iv13,iv14,iv15,iv16,iv17,iv18,iv19,iv20 };

iv1 = (ImageView) findViewById(R.id.imageView1);
    iv2 = (ImageView) findViewById(R.id.imageView2);
    iv3 = (ImageView) findViewById(R.id.imageView3);
    iv4 = (ImageView) findViewById(R.id.imageView4);
    iv5 = (ImageView) findViewById(R.id.imageView5);
    iv6 = (ImageView) findViewById(R.id.imageView6);
    iv7 = (ImageView) findViewById(R.id.imageView7);
    iv8 = (ImageView) findViewById(R.id.imageView8);
    iv9 = (ImageView) findViewById(R.id.imageView9);
    iv10 = (ImageView) findViewById(R.id.imageView10);
   iv11 = (ImageView) findViewById(R.id.imageView11);
    iv12 = (ImageView) findViewById(R.id.imageView12);
    iv13 = (ImageView) findViewById(R.id.imageView13);
    iv14 = (ImageView) findViewById(R.id.imageView14);
    iv15 = (ImageView) findViewById(R.id.imageView15);
    iv16  = (ImageView) findViewById(R.id.imageView16);
    iv17 = (ImageView) findViewById(R.id.imageView17);
    iv18 = (ImageView) findViewById(R.id.imageView18);
    iv19 = (ImageView) findViewById(R.id.imageView19);
    iv20 = (ImageView) findViewById(R.id.imageView20);

I need to randomly generate ten different indexes with this piece of code. How do I set the visiblity? thanks in advance