What are loaders in Android?

Introduced in Android 3.0, loaders make it easy to asynchronously load data in an activity or fragment. They provide asynchronous loading of data. They monitor the source of their data and deliver new results when the content changes.

What is the function of AsyncTaskLoader object?

Abstract Loader that provides an AsyncTask to do the work. See Loader and LoaderManager for more details. Here is an example implementation of an AsyncTaskLoader subclass that loads the currently installed applications from the package manager.

What is AsyncTaskLoader?

AsyncTaskLoader is used to perform an asynchronous task in the background of the application, so the user can also interact with the application during that process. As soon as the task is completed, the result will be updated to the interface.

What is cursor loader in Android?

A CursorLoader is a specialized member of Android’s loader framework specifically designed to handle cursors. In a typical implementation, a CursorLoader uses a ContentProvider to run a query against a database, then returns the cursor produced from the ContentProvider back to an activity or fragment.

When onLoadFinished is called?

onLoadFinished(Loader, D) – called when a loader has finished loading data. onLoaderReset(Loader) – called when a previously created loader is being reset (when you call destroyLoader(int) or when the activity or fragment is destroyed , and thus making its data unavailable.

What is the difference between adapter and loader in Android?

Both provide an abstraction for data access, but the Loader performs the query in the background whereas an Adapter executes in the current (presumably UI) thread. For example, a straightforward way to access a Content Provider is with a SimpleCursorAdapter.

Is AsyncTaskLoader deprecated?

1 Answer. The framework implementation of Loader is deprecated, along with the framework implementation of Fragment . what alternative should we used instead? Use the Support Library edition of AsyncTaskLoader .

What is onPostExecute?

AndroidMobile DevelopmentProgramming. Android AsyncTask going to do background operation on background thread and update on main thread. In android we cant directly touch background thread to main thread in android development. asynctask help us to make communication between background thread to main thread.

What is the difference between AsyncTask and AsyncTaskLoader?

AsyncTask will be re-executed as background thread again, and previous background thread processing was just be redundant and zombie. AsyncTaskLoader will be just re-used basing on Loader ID that registered in Loader Manager before, so avoid re-executing network transaction.

Is CursorLoader deprecated?

This class was deprecated in API level 28. A loader that queries the ContentResolver and returns a Cursor . A CursorLoader must be built with the full information for the query to perform, either through the CursorLoader(android. …

Why async task is bad?

Official Reason for Deprecation of AsyncTask AsyncTask was intended to enable proper and easy use of the UI thread. However, the most common use case was for integrating into UI, and that would cause Context leaks, missed callbacks, or crashes on configuration changes.

How to use asynctask loader in Android app?

android.content.AsyncTaskLoader is a loader that uses AsyncTask to perform the task. It is an abstract class and to use it we need to extend and override its methods. In our example we will iterate a list using ListView. Find some methods that need to be overridden.

When to use baseadapter in asynctaskloader example?

BaseAdapter is a common implementation for other adapters. While using AsyncTaskLoader we need to extend it and override at least a method i.e loadInBackground which perform the user task. After loading data we will set data to adapter and finally call notifyDataSetChanged () to reflect list view on UI.

How to override loadinbackground method in asynctaskloader?

Find some methods that need to be overridden. loadInBackground () : Performs actual task in background and returns the result. onCanceled (D data) : This method is called if task is cancelled before completion. It is used to clean up data post cancellation.

Is there any reason to use asynctask anymore?

Since AsyncTaskLoader does everything AsyncTask can do, and additionally has in-built best practice features such as thread-duplication & pre-mature death prevention. Is there any reason to use AsyncTask anymore? Or should I just blindly use AsyncTaskLoader everywhere AsyncTaskLoader is only useful to load data in an Activity or Fragment.