I'm trying to create an AlertDialog where both a message (in a TextView, for instance) and a MultiChoice-list can be displayed at the same time, but I'm a bit lost as to how to do it.
Will I have to create my own subclass of AlertDialog, or is there an easier way to do it?
Use DialogFragment for customization
for more info https://developer.android.com/reference/android/app/DialogFragment.html
You could create a normal AlertDialog but, instead of using the setMessage() method, you could just use a custom layout (you can inflate it in a View or even create a custom view) and use then the setView() method of the AlertDialog class.