Question

public class ExpAdapter : BaseExpandableListAdapter
{
  private int seed = 1000;

  public override View GetChildView(int groupPosition, int childPosition, bool isLastChild, View convertView, ViewGroup parent)
    {
        if (convertView == null)
        {
            LayoutInflater inflater = (LayoutInflater) context.GetSystemService(Context.LayoutInflaterService);
            convertView = inflater.Inflate(Resource.Layout.inspection_row_2, null);
        }

        int currentID;
        Random randomizer = new Random(seed);

        TextView question = (TextView) convertView.FindViewById(Resource.Id.questionText);
        RadioGroup radio = (RadioGroup) convertView.FindViewWithTag("actionGroup");
        currentID = randomizer.Next(1,101);
        radio.Id = currentID;
        RadioButton pass = (RadioButton) convertView.FindViewWithTag("passed");
        currentID = randomizer.Next(1,101);
        pass.Id = currentID;
        RadioButton fail = (RadioButton) convertView.FindViewWithTag("failed");
        currentID = randomizer.Next(1,101);
        fail.Id = currentID;
        RadioButton correct = (RadioButton)convertView.FindViewWithTag("corrected");
        currentID = randomizer.Next(1,101);
        correct.Id = currentID;
        RadioButton na = (RadioButton)convertView.FindViewWithTag("na");
        currentID = randomizer.Next(1,101);
        na.Id = currentID;

        string[][] items = questions.childItems();
        question.Text = items[groupPosition][childPosition];

        seed++;

        return convertView;
    }
}

Using a breakpoint to step through the above, currentID = 1 throughout execution. The above method gets called repeatedly as MonoDroid creates the child group of controls under the parent group and currentID is ALWAYS = 1. I have also tried creating currentID and randomizer as private static variables within the entire class. Same result.

EDIT: I attempted to create the new Random instances with a seed value that differed for each call to GetChildView. Code is edited above to show how I did that. Still the value of currentID is always = 1. Below is screen shot of information for randomizer in Locals. This information looks the same regardless of what the seed number is. ???

Answer 1

Randomizer is calculated with system time in milliseconds. So, if you call it rapidly, ie in same millisecond, they get seeded with same number, thus resulting in same random number.