Access data in the background using a Loader

Any potentially long-running operations should not be done on the UI thread, as this can cause your application to be slow or become non-responsive. The Android OS will bring up the Application Not Responding (ANR) dialog when apps become non-responsive.

Since querying databases can be time-consuming, Android introduced the Loader API in Android 3.0. A Loader processes the query on a background thread and notifies the UI thread when it finishes.

The two primary benefits to Loaders include:

  • Querying the database is (automatically) handled on a background thread
  • The Query auto-updates (when using a Content Provider data source)

To demonstrate a Loader, we will modify the previous SQLite database example to ...

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