How to populate a message text input base on another message text input.

Question

Hi,
Everybody,i have 5 message text input a,b,c,d,e(say)
now a=b+c+d+e,Now am inserting value for a,b,c,d and after giving this 4 value the value of e will automatically populate.How can we achieve this.
Thanks

Answer 1

Babu,
but my question is why we need to attach ppr for all the 4 elements
we can attach a ppr for 4 element and make a validatiion on other 3 elements, if values are entered or not, if not throw a appropriate exception, if all the values are entered then make the caluculation and assign it to the transient attribute.
Babu, y would I throw the error if user hasn't entered all 4 i just have to show addtion of all four elements in fifth.Other point is how will you decide which is fourth element, any element can be considered as fourth depnds from where u start counting :)!Unless I have attached PPR to all 4, you won't catch any change event in any of the four elements.The event will be one only but all 4 elements will be attached to same(i.e. all will have same event name).Just visulaise the scenario...., you will get what I am trying to say.
--Mukul