How to understand such Java code with lambda?

Question

Android

Kind
There is a fragment, in it it is a lot of CheckedTextView. In fragment

implements View.OnClickListener

to make on all CheckedTextView listener
So here is

checked.setOnClickListener(this::onClick);
or
checked.setOnClickListener(this);

It looks like the output is the same, but what's the difference?

Answer 1

The difference is that when used, the fragment may not implement View.OnClickListener, because the listener is not it, but an anonymous class generated by the lambda. If your fragment still implements View.OnClickListener, then the lambda is completely out of place and redundant.

Answer 2

The difference is that in the first case, an additional anonymous class is created.