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Dialog vs DialogFragment
The Dialog class is the base class for dialogs, but you should avoid instantiating Dialog directly. Instead, use one of it’s subclasses. Dialogs are entirely dependent on Activities. If the screen is rotated, the dialog is dismissed.
A DialogFragment is a fragment that displays a dialog window, floating on top of its activity’s window. This fragment contains a Dialog object, which it displays as appropriate based on the fragment’s state. Using DialogFragment to manage the dialog ensures that it correctly handles lifecycle events such as when the user presses the Back button or rotates the screen.
Links
https://developer.android.com/reference/android/app/Dialog.html https://developer.android.com/reference/android/app/DialogFragment https://developer.android.com/guide/topics/ui/dialogs