dynamic dropdowns

[Patrick Mallahan]

If i want a user to be able to add another drop down box by clicking a button how would I do this?
[ July 19, 2005: Message edited by: Bear Bibeault ]

[Bear Bibeault]

You could either make a round-trip to the server to have the JSP re-write the page, or, if all the necessary data is at your disposal, you could do it all with Javascript on the client side. Or, you could use a combination Ajax approach.

Which makes more sense for your situation?

[Patrick Mallahan]

Probably JavaScript since the data is going to be the same in the drop down lists. I just need an onClick event on a link that creates a similar drop down list.

[Bear Bibeault]

Easiest course of action would probably be to render the drop-down on the first pass and hide it with a CSS display rule. Then, in the onclick hander, you can simply reveal it.

Moving to the HTML/Javascript forum for further discussion.

[Patrick Mallahan]

but what if somone wanted multiple >2 drop downs?

[Bear Bibeault]

You can hide and reveal as many as you want.

Now, if the values in the dropdowns are not known up-front, and they are dependent on what the user selects, that's a horse of a different color.

Luckily, it's also a horse that's been discussed in this very forum many times.

[Bear Bibeault]

Btw, I changed the subject of this post to reflect the specific question better.

[Patrick Mallahan]

future reference than, because this may actully help me a lot. How do I change the values in drop down 2 based on dropdown one without reloading the page?

[Bear Bibeault]

If you know what the values will be up-front, and the number is relatively small, you can just create Javascript variables with the info and do it all in Javascript on the client side.

If you need to contact the server without a page reload, you can use XMLHttpRequest (aka Ajax technology) to make a "behind the scenes" request to the server to obtain the info you need to repopulate the dropdown(s).