Posts by Violet_82 Page 22

Violet_82 89 Posting Whiz in Training

12 Years Ago

Re: jquery :first selector with hidden elements

ahhhh ok I understand now, so it select the first hidden one! thanks for clarifying that! sorry I think I still have troubles getting this idea of multi filtering in my head. I interpreted that as selecting the hidden divs and then the first one, whether it was hiddin or not

Web Development javascript javascript-jquery

Violet_82 89 Posting Whiz in Training

12 Years Ago

usb main charger for laptop

Hi chaps, I have a problem with my dell xps 17 lappy, the connector for the main is really dodgy inside the laptop itself therefore charging it is a nightmare. I was wondering if there is such a thing as a USB main charger that can be plugged in to a usb port of the lappy rather than to the usual power cable connector and charge the battery (I assume the computer needs to be on for it to work).
Have you ever heard anything like that?
thanks

Microsoft Windows windows-vista-7-8

Violet_82 89 Posting Whiz in Training

12 Years Ago

jquery :first selector with hidden elements

Hi there, I was wondering if anybody can help me understanding this code please - well it's more about the usage of :first really):

<!DOCTYPE html>
<html>
<head>
  <style>
span { color:red; cursor:pointer; }
div { margin:3px; width:80px; display:none;
  height:80px; float:left; }
  div#one { background:#f00; }
  div#two { background:#0f0; }
  div#three { background:#00f; }
</style>
  <script src="http://code.jquery.com/jquery-1.9.1.js"></script>
</head>
<body>
  <span>Click here...</span>

    <div id="one"></div>
    <div id="two"></div>
    <div id="three"></div>
<script>
$(document.body).click(function () {
  $("div:hidden:first").fadeIn("slow");
});
    </script>

</body>
</html>

Now, the purpose of this code - taken from http://api.jquery.com/fadeIn/ - is to reveal a square each time you click on the link. What I am not clear about is how the selector works: $("div:hidden:first"). this selects every first hidden div, but the :first filter selects only one element, so I assume it will select always the first div because it is the first one! That said if I remove it to obtain $("div:hidden") then the 3 divs appear at the same time when you click the link. SO my question is, how does the :first filter manage to select only one div each time the link is selected?
thanks

Web Development javascript javascript-jquery

Violet_82 89 Posting Whiz in Training

12 Years Ago

Re: building a simple airline reservation system exercise

ah sorry, I forgot to print the message when the function is first called, plus a few more changes, now it works!!! aaaaaaaaaaaahhh! I can't believe it, it wooooorksss!!
Right, big big thanks to all you guys who've contributed to this thread, thanks a lot for your help and patience!
I have learned a lot from this exercise, and I will make absolutely sure I will come up with a very good pseudocode before I start coding and not the other way around (which is what I have essentially done this time).
Here is the final version of the program in case anybody wants to use it (I doubt it) or use it like a starting point (a bit more likely!)
I suppose I have looked at it so many times that now I miss the obvious!

//ex 7.19 p 333 deitel and deitel
//Seats.java
public class Seats{
    private final int NUMBER_OF_SEATS = 10;
    private boolean[] seats;


    //constructor
    public Seats(){
        //initializing array
        seats = new boolean[ NUMBER_OF_SEATS ];
        //set values to false - doesn't it do automatically?
        for( int counter = 0; counter < seats.length; counter++ ){
            seats[ counter ] = false;
        }//end of loop      
    }//end of constructor

    public int assignSeat( int type){
        int seatPlace = -1; //default seatPlace value
        int firstI = 0;  // firstIndex
        int lastI = 4;
          if ( type == 2 ){
            firstI += 5;//second index
            lastI += 5;
          }  
          for ( int i = firstI; i <= lastI; i++ ){ …