How to pass values in 1 form to another

[maveric]

Hi all..

I am developing an application which require passing of values from one form (dialog) to another form (Dialog)..
i had tried many ways but could not attain in getting so...

Actually what i need is....
I have taken an qwt plot widget in the if i right click on plot i get a context menu...
when i choose Change Scale option i get another small dialog asking for entering a value in the line edit..
now what i need is when i enter a particular value in the small dialog it should come back to the main dialog and change the x-axis scale ...
i Have tried enough methods... but failed..
well i am not even getting a particular value to the main dialog...

so any one please help me how to do this...

Thanks in advance....