Alex Alex - 10 months ago 50
Android Question

Updating Parent Fragment from Child Fragment

In my android application, I have two Fragments. Parent Fragment contains list of available Filter Types and when a particular Filter Type is clicked (in Parent Fragment - Yellow Background) corresponding Child Fragment (Pink Background) opens with list of available options for selected filter type. My requirement is once User select/deselect an option in child fragment, it should reflect/update option count (Green color) in parent Fragment.

Please check attached wireframe.

enter image description here

Answer Source

You can use Otto Bus for comunications between Fragments, fragments-activities, services, etc.

Maybe, the first time you can be a little weird if you have not used before but it is very powerful and very easy to use. You can find the library and a tutorial here:

An example. In your adapter or where you have your item click event you cand send a Object by the Bus.

In your bus you invoque the post method and pass the object. (I recommended create a singleton for Bus).

The singleton Bus Provider.

 * Canal de comunicacion
public class BusProvider {

    private static final Bus REST_BUS = new Bus(ThreadEnforcer.ANY);
    private static final Bus UI_BUS = new Bus();

    private BusProvider() {};

    public static Bus getRestBusInstance() {
        return REST_BUS;

    public static Bus getUIBusInstance () {
        return UI_BUS;

You send a Object in the bus (in your child fragment) like this:


And in your parent fragment you subscribe for this event:

public void activitySelected(final Item itemSelected) {


Hope it helps you!!