Cannot modify header information

Hello everyone

I am currently developping a plugin that manage two lists (such as the comments list).

Everything is in place and looks ok, and apparently works fine, Except for the checkbox options : i have the following message :

Warning: Cannot modify header information – headers already sent by (output started at C:\Vn\wptest\wp-admin\menu-header.php:148) in C:\Vn\wptest\wp-includes\pluggable.php on line 694

what surprises me most is when i get rid of the javascript files i use to insert in the plugin page, the message does not appear when using the checkbox options.

Any idea ?

my code is very similar to the comments list :

when a checkbox is checked and a button activated, the list processes each item checked in the list and then ‘wp_redirect’ to the same php file (the list) to display a message such as ‘x items processed’.