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What is the difference? The android documentation doesn't have a description for notifyDataSetInvalidated(). I was thinking maybe you call that function to notify all registered listeners, but use notifyDataSetChanged() to not notify them?

Spidy
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1 Answers1

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Changed means the data set changed. Individual items updated, or items were added or removed. Invalidated means the data source is no longer available.

adamp
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    To expand on this, a response from Romain Guy: "notifyDataSetInvalidated() means that the data inside the adapter is no longer valid. This will cause ListView to stop populating. There should seldom be any reason to use it." – Glendon Trullinger Jun 17 '11 at 00:25
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    To further explain @Glendon's comment, [this Google groups thread](https://groups.google.com/d/topic/android-developers/1tsRQczqbt0/discussion) and [this one](https://groups.google.com/d/topic/android-developers/WJshF8aZeUY/discussion) contained similar questions that were answered by an Android framework engineer named Romain Guy. – Jeff Axelrod Jun 22 '11 at 14:49
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    If anyone is interested in what happens programmatically behind the scenes when calling these methods, see my answer [here](http://stackoverflow.com/questions/3219779/android-what-does-adapter-notifydatasetinvalidated-do/7734032#7734032) – Tony Chan Oct 12 '11 at 00:28
  • The documentation for these methods has been expanded for an upcoming release. – adamp Oct 12 '11 at 04:39