android.app.Application cannot be cast to android.app.Activity

You are passing the Application Context not the Activity Context with

getApplicationContext();

Wherever you are passing it pass this or ActivityName.this instead.

Since you are trying to cast the Context you pass (Application not Activity as you thought) to an Activity with

(Activity)

you get this exception because you can't cast the Application to Activity since Application is not a sub-class of Activity.

in case your project use dagger, and then this error show up you can add this at android manifest

   <application
        ...
        android: name = ".BaseApplication"
        ...> ...

In my case, when I'm in an activity that extends from AppCompatActivity, it did not work(Activity) getApplicationContext (), I just putthis in its place.

You are getting this error because the parameter required is Activity and you are passing it the Application. So, either you cast application to the Activity like: (Activity)getApplicationContext(); Or you can just type the Activity like: MyActivity.this