jsp doubts....

Replies

• 

  Anoop Kumar

  I suppose you are using combox to populate date and then selecting it.
  Initially on page load do not select anything then add following like this
  

  
  Anchor1
  Anchor2
  Anchor3
  Anchor4
  
   

  you can send pass parameter also.
  then in yourFunction() javascript: add how to redirect a page using javascript? - Javascript
  You can use Location href Property
• 

  lovejeet

  hey thanks for the reply, but you didn't got the question i guess. sorry if was a bit ambiguous.
  it's for combo box only, where there are several entities, say x, y and z. what i want is that when user selects x, it should redirect to another page say abc.jsp, for y, it should redirect to pqr.jsp and so on....
• 

  Anoop Kumar

  what are xyz....
  if these are radio buttons then just use OnClick() event and call the javascript function.
• 

  lovejeet

  xyz are different entities like anchor1, anchor2 in your example. n ya, onclick() method is a nice solution to that....
• 

  PraveenKumar Purushothaman

  Wait... Lemme say... You got a combobox with values Page 1, Page 2, Page 3. And upon selecting them, they should redirect you to One.jsp, Two.jsp, and Three.jsp accordingly. If this is the case, you can try this:
  

  
    Page 1
    Page 2
    Page 3
  
   
  

  This works in almost all the browsers. Checked just now. Try and let me know... 😀
• 

  lovejeet

  hey thanks a lot #-Link-Snipped-#. yup done. now the next problem is the drop down menu's. i want my 3rd dropdown menu to be based on the values of my 2nd menu, and dat to be dependent on the 1st one. how to do that now???
• 

  PraveenKumar Purushothaman

  lovejeet

  hey thanks a lot #-Link-Snipped-#. yup done. now the next problem is the drop down menu's. i want my 3rd dropdown menu to be based on the values of my 2nd menu, and dat to be dependent on the 1st one. how to do that now???

  So it means 3 individual dropdowns huh???
• 

  PraveenKumar Purushothaman

  You mean like this? The value of the next combo box is dependent on the previous one???
  
  
• 

  lovejeet

  yup. like this. it includes dynamic selection for some dropdown menu's using database too. 😕
• 

  PraveenKumar Purushothaman

  lovejeet

  yup. like this. it includes dynamic selection for some dropdown menu's using database too. 😕

  I guess its getting complicated... Then you got two choices:
  1. Ajax Update
  2. Page Refresh
  
  Which one do you prefer?
• 

  lovejeet

  i do not prefer ajax. wanna keep it as the last option. i tried it for two drop down menu's and it wasn't much tought. but when it comes to more than two and when retrieving the values from database, its all over my head....😛
• 

  PraveenKumar Purushothaman

  If you were using ASP.net, it is damn easy... Check this out: #-Link-Snipped-#
• 

  PraveenKumar Purushothaman

  And I saw this in StackOverflow. Seems promising. Read on...
  
  You need to download JQuery (JavaScript framework) and include that in the head section of the HTML.
  

  Inside the OnChange function for first dropdown call the function to populate the subsequent dropdowns.
  

  $(document).ready(function() {
    $('#DDIdParent').change(function() {
        populateChildDropdown('DDIdParent');
    });
});

  The function is a s follows:
  

  function populateChildDropdown(ddId) {
    var dd = $('#' + ddId);
    $.getJSON('json/mapping?dd=' + ddId, function(opts) {
        $('>option', dd).remove(); // Clear old options first.
        if (opts) {
            $.each(opts, function(key, value) {
                dd.append($('').val(key).text(value));
            });
        } else {
            dd.append($('').text("Please select the parent DD"));
        }
    });
}

  Inside your Servlet's doGet method, you will have a code like this to get the value of subsequent dropdown from the database as a JSON String:
  

          Map options = yourDao.callDatabase(parameter);
        String json = new Gson().toJson(options);
        res.setContentType("application/json");
        res.setCharacterEncoding("UTF-8");
        res.getWriter().write(json);

  You need to map the json/mapping to your servlet inside web.xml. You can also pass parameters from the jquery function if needed.
• 

  lovejeet

  sir ji i want that in jsp, no php or .net allowed...😔
• 

  Anoop Kumar

  Without ajax you need to refresh the page.
  using onChange() even submit the page with some flag. and on sevlet/ jsp, you are using, get all the values. now fetch values for next drop down menu on basis of latest dropdown menu. and come back to the page with all values. and populate the your latest dropdown menu and set all the previous values.
  why not Ajax. you are just fetching data from database.😀
• 

  PraveenKumar Purushothaman

  lovejeet

  sir ji i want that in jsp, no php or .net allowed...😔

  Sir Ji! It is JSP! 😀
  
  And if you really know JavaScript, those things inside PHP block are JavaScripts. No where I have used PHP! Lolz...
• 

  Prasad Ajinkya

  This smells like an assignment 😀
  
  But perhaps you need to do this via simply Javascript.
• 

  lovejeet

  @praveen- oops..... sorry that was a bit confusing by that header of 'php'. will try the code.
  @kidakaka- hahaha.......yup, a part of my project only, but what all i could try was for two menu's and that to without the database. rest i need to take the help...😀
• 

  Prasad Ajinkya

  Here's what you do -
  Declare a javascript array for the URLs.
  
  In the dropdown, the values of each option should map to the index of this URL array.
  
  When the form is submitted, simply invoke a function which will take the value of the dropdown, retrieve the particular URL from that value and change the location to that.
• 

  PraveenKumar Purushothaman

  kidakaka

  Here's what you do -
  Declare a javascript array for the URLs.
  
  In the dropdown, the values of each option should map to the index of this URL array.
  
  When the form is submitted, simply invoke a function which will take the value of the dropdown, retrieve the particular URL from that value and change the location to that.

  Even then it becomes an AJAX Call right?
• 

  Prasad Ajinkya

  Nope. Its still Javascript. Why go into the trouble of AJAX?
  

  
  
  
  
  
      Google
      CE
      Kidakaka
  
  
  
  
  

  Here's the code of what I was thinking.