Prepopulate checkbox & checkboxes [#checked] with TRUE or FALSE

Thank you for the patch
Worked also with node checkbox with a small modification
edit[field_designers][und][10]=true

if ($form['#type'] == 'checkbox' && $requestslice >= 1){
  $form['#checked'] = 1;
}

Just attaching an updated patch since I had to use it for my site.

There is an issue with urls like this "edit[field_designers][und][10]=true". Overlay redirect URL try to create 9 array indexes with empty values.

We changed the code to:

if ($form['#type'] == 'checkboxes'){
  $form[$requestslice]['#checked'] = true;
}

and use urls like :

edit[field_designers][und]=10

the first patch worked for me. Thank you!!!

Here is a version that works for checkbox & checkboxes widgets and allows one to check & uncheck fields by either setting a value or not:

Checkboxes:

checked : edit[field_interest][und][1]=1

not checked : edit[field_interest][und][3]=0

Checkbox:

checked : edit[field_thing][und]=1

not checked : edit[field_thing][und]=0

Thanks a lot for the patch jpstrikesback. It didn't quite apply properly for me so I've re-rolled it using branch 7.x-2.x.

Edit field name

The patch reroll by @eddie_c in #6 works great for me.

+1 for #6

I can confirm #6 works great
Please review and submit it to dev

Works great for me, for taxonomy term ref fields too.

Committed, Thanks!

Do you have a solution for drupal 8 - 9 ?Thanks