Question

I was wondering if it is a good practice to use anonymous listeners?

For example I have a list of 50 items. Each of them has a onClickListener which is implemented using anonymous listener. Does that mean that I create 50 new items in to heap?

for (x;x;x) {
   item.setOnClickListener(new OnClikListener() {
      ...
    });
}

And if I just create 1 listener object and then assign those 50 list items to that single listener. Will it be more efficient?

OnClickListener listener = new OnClickListener() {
   ...
};

for (x;x;x) {
   item.setOnClickListener(listener);
}

Answer 1

The fact that it’s anonymous is irrelevant. Every object instance you create goes on the heap. If you can reuse the same listener for many buttons, then definitely do it: it will need less memory, and will generate less garbage.