Warning: Missing argument 1 for CrudKit\Pages\BasicLoginPage::preprocess(), called in C:\xampp\htdocs\kit\vendor\skyronic\crudkit\src\CrudKit\CrudKitApp.php on line 51 and defined in C:\xampp\htdocs\kit\vendor\skyronic\crudkit\src\CrudKit\Pages\BasicLoginPage.php on line 67

[ispcpr]

Warning: Missing argument 1 for CrudKit\Pages\BasicLoginPage::preprocess(), called in C:\xampp\htdocs\kit\vendor\skyronic\crudkit\src\CrudKit\CrudKitApp.php on line 51 and defined in C:\xampp\htdocs\kit\vendor\skyronic\crudkit\src\CrudKit\Pages\BasicLoginPage.php on line 67

[rstuckart]

In /vendor/skyronic/crudkit/src/CrudKit/CrudKitApp.php, public function useLogin calls $login->preprocess (); I changed it to $login->preprocess ($this); and there are no errors.

[nzjs]

Had the same issue, resolved with the fix by @rstuckart

[sidgitind]

@rstuckart solution works

[Byter-Bit]

Again, rstuckart's solution works; line 52 in CrudKitApp.php. Many thanks rstuckart.

[marco-gagliardi]

tried the solution, no more errors, but logging in with provided credentials apparently does nothing.. (I see the login form, and no error/wrong credentials message is shown)

[twysto]

If you look at the preprocess function in the BasicLoginPage class (vendor\skyronic\crudkit\src\CrudKit\Pages\BasicLoginPage.php) you will notice that the $app parameter is never used anywhere.
In my opinion a better fix to this issue would be to remove this $app parameter rather than passing an object that is useless.

For those who have difficulties to login, the Login/Pass to use are:
admin/demo
or
user/demo