Question

I have a string array which holds the names of the weekdays:

private final String[] weekdays = new String[]{"Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"};

I have set Monday as the first day of the week by default.

Now I have given the user the option to select if s/he wants to set either Sunday or Monday as the first day of the week:

if (firstDay == 0) {
    holder.txtWeekdays.setText(weekdays[position]);
 }

Using the same String array how do I set Sunday as the first day of the Week?

else {
     holder.txtWeekdays.setText(weekdays[position]-1);  //this returns an error 
}

UPDATED CODE:

public class CalendarWeekAdapter extends BaseAdapter{

private final String[] weekdays = new String[]{"Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"};
Context mContext;

   private LayoutInflater mInflater;
   public CalendarWeekAdapter(Context c)
   {
          mContext=c;
          mInflater = LayoutInflater.from(c);
   }
   public int getCount()
   {
          return weekdays.length;
   }
   public Object getItem(int position)
   {
          return position;
   }
   public long getItemId(int position)
   {
          return position;
   }
   public View getView(int position, View convertView, ViewGroup parent)
   {
          ViewHolder holder=null;
          if(convertView==null)
          {
                 convertView = mInflater.inflate(R.layout.calendar_week_gridcell, parent,false);
                 holder = new ViewHolder();
                 holder.txtWeekdays=(TextView)convertView.findViewById(R.id.weekdays);
                 if(position==0)
                 {                             
                       convertView.setTag(holder);
                 }
          }
          else
          {
                 holder = (ViewHolder) convertView.getTag();
          }

          if (firstDay == 0) {
              holder.txtWeekdays.setText(weekdays[position]);
          }
          else {
              holder.txtWeekdays.setText(weekdays[position]); 
          }

          return convertView;
   }

}
static class ViewHolder
{        
      TextView txtWeekdays;                 
}

Answer 1

You are trying to subtract 1 from a string. That’s not really going to work.

What you need to do is create a method that returns the day of the week. Something like this:

public String getDayOfWeek(int day, int firstDay) {
   String[] weekdays;
   if (firstDay == 0)
      weekdays = new String[]{"Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"};
   else
      weekdays = new String[]{"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
   return weekdays[day];
}

Now, you COULD do this by position (using weekdays[position - 1]), but the above will help you avoid errors in your code (indexing -1 for example), and give you more clarity as to what is being returned.