Question

I’m trying to create an android application which will generate random series of values (integer numbers in this case) in a given range (but NOT equal between them) and display them in a simple TextView

Let’s say we have the range R = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]

Each time I press the button “Generate” I want to randomly generate 5 different results

Example for each “Generate”:

• 4, 9, 2, 12, 10
• 5, 1, 6, 8, 13
• 10, 4, 6, 8, 2
• etc…

EDIT (works now) Thanks for all the help!

public class random extends Activity {


static final Integer[] data = new Integer[] {
    1, 2, 3, 4, 5, 6, 7, 8
    };


@Override
public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    setContentView(R.layout.main);

    Random r = new Random();

    Set<Integer> mySet = new HashSet<Integer>();
    while (mySet.size() < 5) {
       int idx = r.nextInt(data.length);
       mySet.add(data[idx]);
    }

    String text = "";
    for (Integer i : mySet) {
       text = text + i + ", "; 
    }
       TextView Numbers = (TextView)findViewById(R.id.shownumbers);
       Numbers.setText(text);
  }
}

Answer 1

Random r = new Random(<a seed number>);

Set<Integer> mySet = new HashSet<Integer>();
while (mySet.size() < 5) {
   int idx = r.nextInt(<length of your data>)
   mySet.add(data[idx]);
}

data contains your range numbers.

String text = "";
for (Integer i : mySet) {
   text = text + i + ", "; 
}

set this text in your TextView.