What is lifecycle for RecyclerView adapter?

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I think the best way to do that would be to:

  1. Keep a subscription reference in the SiteAdapter.ViewHolder
  2. unsubscribe the subscription object in onBindViewHolder (it’s called when the ViewHolder is reused)
  3. Keep the CompositeSubscription object in your adapter
  4. Use the onDetachedFromRecyclerView method of your Adapter to unsubscribe the compositeSubscription

Like so:

public class SiteAdapter extends RecyclerView.Adapter<SiteAdapter.ViewHolder> {

    private CompositeSubscription compositeSubscription = new CompositeSubscription();

    // other needed SiteAdapter methods

    @Override
    public void onBindViewHolder(SiteAdapter.ViewHolder holder, int position) {
        if (holder.subscription != null && !holder.subscription.isUnsubscribed()) {
            compositeSubscription.remove(holder.subscription);
            // this will unsubscribe the subscription as well
        }
        Site site = sites.get(position);
        holder.siteName.setText(site.getName());
        requestHolderLogo(holder, site.getLinks().getLogoUrl());
    }

    private void requestHolderLogo(final SiteAdapter.ViewHolder holder, final String logoUrl) {
        holder.subscription = presenter.bitmap(logoUrl)
                .subscribe(
                        bitmap -> {
                            holder.siteLogo.setImageBitmap(bitmap);
                            holder.siteLogo.setVisibility(View.VISIBLE);
                        },
                        error -> {
                            holder.siteName.setVisibility(View.VISIBLE);
                        });
        compositeSubscription.add(holder.subscription);
    }

    @Override
    public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
        compositeSubscription.unsubscribe();
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {

        public Subscription subscription;

        // some holder-related stuff

        public ViewHolder(View itemView) {
            super(itemView);
            // init holder
        }
    }
}

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