android - DialogFragment advantages over AlertDialog

When developing an Android app, I've read that it's recommended to use DialogFragment instead of using directly an AlertDialog to show alerts and confirmations.

This is done, for example, on DialogFragment's Documentation: http://developer.android.com/reference/android/app/DialogFragment.html

People also say they prefer this here:
Android DialogFragment vs Dialog

I would like to know the advantages of this approach, since the code becomes more complex.

Thanks

Answer

Use DialogFragment over Dialog:

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• Since the introduction of API level 13:

  
  
  

  the showDialog method from Activity is deprecated.
  Invoking a dialog elsewhere in code is not advisable since you will have to manage the dialog yourself (e.g. orientation change). Not using the showDialog will result in occasional exceptions, the dialog is not linked to any Activity.

  
  
  

  Note about showDialog:

  
  
  

  
  
  

  reference of Dialog: Activities provide a facility to manage the creation, saving and restoring of dialogs. See onCreateDialog(int), onPrepareDialog(int, Dialog), showDialog(int), and dismissDialog(int). If these methods are used, getOwnerActivity() will return the Activity that managed this dialog.

  
  




• Difference between DialogFragment and AlertDialog

  
  
  

  One thing that comes to mind when reading your question. Are they so much different?
  A DialogFragment is pretty similar to a Dialog, it's just wrapped inside a fragment. From Android reference regarding DialogFragment:

  
  
  

  
  

  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. Control of the
  dialog (deciding when to show, hide, dismiss it) should be done
  through the API here, not with direct calls on the dialog.

  
  




• Other notes

  
  
  
  
  
  • Fragments are a natural evolution in the Android framework due to the diversity of devices with different screen sizes.
  
  
  • DialogFragments and Fragments are made available in the support library which makes the class usable in all current used versions of Android.