IssueTracker

Component used: Data Binding
Version used: 3.4.0-alpha09
Devices/Android versions reproduced on:
Pixel 2 XL/Android 9

android.databinding.ViewDataBinding$LiveDataListener.onChanged cause NullpointerException

       @Override
        public void onChanged(@Nullable Object o) {
            ViewDataBinding binder = mListener.getBinder();
            binder.handleFieldChange(mListener.mLocalFieldId, mListener.getTarget(), 0);
        }

Above code doesn't check nullity of binder which may be null. mListener is a  ViewDataBinding.WeakListener, It's getBinder method goes like this:

 protected ViewDataBinding getBinder() {
            ViewDataBinding binder = get();
            if (binder == null) {
                unregister(); // The binder is dead
            }
            return binder;
        }
When binder is GCed, null is returned and hence LiveDataListener.onChanged will fail with a NullpointerException.