当我更改 LiveData 的观察者时会发生什么

Question

What happens if I have a ViewModel that observes some LiveData With the following line of code

myViewModel.getData.observe(getViewLifeCycle(),Observer);

what if I have anther LiveData data2 inside my view model and I started observing this data.

myViewModel.getData2.observe(getViewLifeCyle(),Observer);

what happens for the first observer? is that considered to be a memory leak? should I remove all the observers on the data before I go observing anther data?

EDIT: I have the following code for a SearchBar that I use to Observe the data from Room Database.

@Override
            public boolean onQueryTextChange(String s) {
                String query =  "%" + s + "%";
                Log.d(TAG, "onQueryTextChange: " + query);
                problemViewModel.getProblemsByQuery(query).observe(getViewLifecycleOwner(),observer);
                return true;
            }
                
                    

I'm concerned with this line.

problemViewModel.getProblemsByQuery(query).observe(getViewLifecycleOwner(),observer);

I repeat it over and over inside the method whenever the text changes. so will that cause a problem?

Answer 1

There is no leak immediately visible here. You can certainly observe as many LiveData as you want simultaneously - as many as you can fit into memory. And they can all share the same observer object, if that's what you want.