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#Fragment examples android#

inflate() method takes three parameters: The id of a layout XML file (inside R.layout), a parent ViewGroup into which the fragment’s View is to be inserted, and a third boolean telling whether the fragment’s View as inflated from the layout XML file should be inserted into the parent ViewGroup. As you can see, the example actually does that by calling layout.inflate(). LayoutInflater is an component which can create View instance based on layout XML files. OnCreateView() method gets a LayoutInflater, a ViewGroup and a Bundle as parameters. View rootView = inflater.inflate(R.agment_sample, parentViewGroup, false) Here’s a sample fragment using onCreateView() for its implementation: public class SampleFragment extends Fragment View onCreateView(LayoutInflater inflater, ViewGroup parentViewGroup, 4.app.FragmentActivity : The base class for all activities using compatibility-based fragment (and loader) features.When using a compatibility package library provided by Google, the following classes are used for implementation. : The class for performing an atomic set of fragment operations.: The class for interacting with fragment objects inside an activity.: The base class for all fragment definitions.

#Fragment examples android#

onDetach() : It’s called after onDestroy(), to notify that the fragment has been disassociated from its hosting activityįragments were added to the Android API in Honeycomb(API 11).

onDestroy() : onDestroy() called to do final clean up of the fragment’s state but Not guaranteed to be called by the Android platform.

If there are things that are needed to be cleaned up specific to the UI, then that logic can be put up in onDestroyView() This is the counterpart to onCreateView() where we set up the UI.

onDestroyView() : It’s called before onDestroy().

onStop() : Fragment going to be stopped by calling onStop().

This is usually where you should commit any changes that should be persisted beyond the current user session

onPause() : The system calls this method as the first indication that the user is leaving the fragment.

onStart() : The onStart() method is called once the fragment gets visible.

If there is something that’s needed to be initialised in the fragment that depends upon the activity’s onCreate() having completed its work then onActivit圜reated() can be used for that initialisation work

onActivit圜reated() :This will be called after onCreate() and onCreateView(), to indicate that the activity’s onCreate() has completed.

This is particularly useful when inheriting the onCreateView() implementation but we need to configure the resulting views, such as with a ListFragment and when to set up an adapter

onViewCreated() : This will be called after onCreateView().

We can return null if the fragment does not provide a UI To draw a UI for the fragment, a View component must be returned from this method which is the root of the fragment’s layout.

onCreateView() : The system calls this callback when it’s time for the fragment to draw its UI for the first time.

You are passed the Activity that will host your fragment onAttach() :This method will be called first, even before onCreate(), letting us know that your fragment has been attached to an activity.Below are the methods of fragment lifecycle. Fragment LifecycleĪndroid fragment lifecycle is illustrated in below image.

The view is then inserted into the ViewGroup parent, and the fragment is alive. The fragment then creates its view and returns it to the activity. Then it gets a reference to the ViewGroup the fragment’s view will be rendered inside. The following diagram shows depicts what happens when a fragment is added to an activity: First the activity obtains a reference to the fragment. The fragment’s view is displayed inside this ViewGroup. A fragment is added to a ViewGroup inside the activity. Because an android fragment is not a view, adding it to an activity looks somewhat different than adding a view (e.g. It is this view which is eventually displayed inside the activity in which the fragment lives. Instead, a fragment has a view inside it. An Android fragment is not by itself a subclass of View which most other UI components are. A activity can contain any number of fragments. A greatest advantage of fragments is that it simplifies the task of creating UI for multiple screen sizes. Fragment should be used within the Activity. Android Fragmentįragment class in Android is used to build dynamic User Interfaces. Today we will learn about Android Fragment Lifecycle and implement a single activity class consisting of two fragments in android application.