androidrx-javaandroid-viewsearchviewrx-java2

Wait until the user stops typing before executing a heavy search in searchview


Search is central in my app and I need it to work well. Right now I have a SearchView. I need to display the results inline, so I'm using this code.

    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            srl.setVisibility(View.GONE);
            return false;
        }

        @Override
        public boolean onQueryTextChange(String query) {
            currentQuery = query;
            if (query.length()>= 3) {
                searchFor(currentQuery);
            } else {
                srl.setVisibility(View.GONE);
            }
            return false;
        }
    });

The problem may be obvious. Because I use firebase, my searchFor() function is rather heavy and I don't need it to be executed for every single letter. This not only destroys the user experience, it sometimes literally crashes my app if you write down longer words.

What I want is to search when the user stops typing. I guess I need to have a handler that delays it by a second and then cancel that handler everytime a letter key is pressed and set a new one. This theoretically makes sense. I just haven't been able to pull this off myself for a searchView.

Help would be appreciated!


Solution

  • The easiest way to achieve that is RxJava's debounce operator.

    enter image description here

    With combination of Jake Wharton's RxBinding you'll end up with something like this:

    RxSearchView.queryTextChanges(searchView)
            .debounce(1, TimeUnit.SECONDS) // stream will go down after 1 second inactivity of user
            .observeOn(AndroidSchedulers.mainThread())
            .subscribe(new Consumer<CharSequence>() {
                @Override
                public void accept(@NonNull CharSequence charSequence) throws Exception {
                    // perform necessary operation with `charSequence`
                }
            });