library/src/main/java/de/mrapp/android/view/Chip.java
public final void addCloseListener(@NonNull final CloseListener listener) {
        Condition.INSTANCE.ensureNotNull(listener, "The listener may not be null");
        listeners.add(listener);
    }
public final void addCloseListener(@NonNull final CloseListener listener) {
        Condition.INSTANCE.ensureNotNull(listener, "The listener may not be null");
        listeners.add(listener);
    }
Adds a new listener, which should be notified, when the chip has been closed.

@param listener
The listener, which should be added, as an instance of the type {@link
CloseListener}. The listener may not be null