title: add value into NSArray with looping xcode
body: <p>My client does not want date of birth input with three separate UIPickerView thus I may need to create three picker view and input value into it. For Birth Date and Month is no problem as adding like that</p>
  
  <pre><code>pickerArray = @[@"1", @"2", @"3", @"4", @"5", @"6", @"7", @"8", @"9", @"10",
                          @"11", @"12", @"13", @"14", @"15", @"16", @"17", @"18", @"19", @"20",
                          @"21", @"22", @"23", @"24", @"25", @"26", @"27", @"28", @"29", @"30", @"31"];
  </code></pre>
  
  <p>But for Birth Year, I don't need to spend my time to manually add year value into UIPickerView. I want to set "start year" and "end year" into loop and add these into UIPickerView. It can be feasible to do?</p>