Can i Create the object of a activity in other class?

Question

i have defined a function in mainactivity now i want to access with another class in my app.I have created a object of the mainactivity by using that object i have called th

Answer 1

You cannot just create objects of Activities by using:

MyActivity activity = new MyActivity();

as you would with normal Java classes. All Activities in Android must go through the Activity lifecycle so that they have a valid context attached to them.

By treating an Activity as a normal Java class, you end up with a null context. As most methods in an Activity are called on its Context, you will get a null pointer exception, which is why your app crashes.

Instead, move all such methods which need to be called from other classes into a Utility class which accepts a valid context in its constructor, and then use that context in the methods to do the work.