Get Application Context Returns Null

Get application context returns null

Create in onCreate() an instance of getApplicationContext() (mContext) then call MyApp.getContext() from everywhere in your app and you will get your application context statically.

public class MyApp extends Application {
    private static Context mContext;

    public static Context getContext() {
        return mContext;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        mContext = getApplicationContext();    
    }
}

Remember to declare into your AndroidManifest.xml

<application android:name="com.mypackage.mypackage.MyApp">
...
...
...
</application>

Why am I getting getApplicationcontext() null?

In the constructor it is way too early to access the app context. Try to move this code into the onCreate method.

More datails about the life cycle can be found in the documentation

getApplicationContext() returns null in Application class

You must use static

public class Shopper extends Application {
private static Context context;

@Override
public void onCreate() {
    super.onCreate();
    context = getApplicationContext();
}

public static Context getContext() {
    return context;
}
}

And use

Shopper.getContext();

getApplicationContext() returns null in a Service

You are running your Service in a different process so it has no communication with the Actual Application process..

Try to remove this line from your service

android:process=":pointservice"

After your application is finished Application context is becomes null. At most situations there is no need to run the service in a different process. Also it is not recommended.

For more information check here

1. Service in another process
2. service reference Example2

Spring application context is null

I think you need specify spring to set autowire these beans. For example

@Autowired
private ApplicationContext springContainer;

Another suggestion is use ApplicationContextProvider which implements springs ApplicationContextAware interface.

public class ApplicationContextProvider implements ApplicationContextAware {
    private static ApplicationContext context;

    public static ApplicationContext getApplicationContext() {
        return context;
    }

    @Override
    public void setApplicationContext(ApplicationContext ctx) {
        context = ctx;
    }
}

You can get the application context via ApplicationContextProvider.getApplicationContext();

Why getContext() in fragment sometimes returns null?

First of all, as you can see on this link, the method onCreateView() inside the fragment's lifecycle comes after onAttach(), so you should have already a context at that point. You may wonder, why does getContext() return null then? the problem lies on where you are creating your adapter:

App.getApiService().getLatestNews().enqueue(new Callback<LatestNews>() {
        @Override
        public void onResponse(Call<LatestNews> call, Response<LatestNews> response) {
            if (response.isSuccessful() && response.body().isSuccessfull()){
                adapter = new LastNewsRVAdapter(getContext(), response.body().getData(), sideBanner);
                rvLatestNews.setAdapter(adapter);
                tvSonkuKabar.setVisibility(View.VISIBLE);
            }
        }

        @Override
        public void onFailure(Call<LatestNews> call, Throwable t) {

        }
    });

Though you are specifying a callback in onCreateView(), that does not mean the code inside that callback will run at that point. It will run and create the adapter after the network call is done. With that in mind, your callback may run after that point in the lifecycle of the fragment. What I mean is that the user can enter that screen (fragment) and go to another fragment or return to the previous one before the network request finishes (and the callback runs). If that happens, then getContext() could return null if the user leaves the fragment (onDetach() may have been called).

Besides, you can have memory leaks also, in case the activity is destroyed before your network request finishes. So you have two issues there.

My suggestions to solve those issues are:

1. in order to avoid the null pointer exception and the memory leak, you should cancel the network request when the onDestroyView() inside the fragment is being called (retrofit returns an object that can cancel the request: link).

2. Another option that will prevent the null pointer exception is to move the creation of the adapter LastNewsRVAdapter outside the callback and keep a reference to it in the fragment. Then, use that reference inside the callback to update the content of the adapter: link

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