FastAdapter

The RecyclerView is one of the most used widgets in the Android world, and with it you have to implement an Adapter which provides the items for the view. Most use cases require the same base logic, but require you to write everything again and again.

The FastAdapter is here to simplify this process. You don't have to worry about the adapter anymore. Just write the logic for how your view/item should look like, and you are done. This library has a fast and highly optimized core which provides core functionality, most apps require. It also prevents common mistakes by taking away those steps from the devs. Beside being blazing fast, minimizing the code you need to write, it is also really easy to extend. Just provide another adapter implementation, hook into the adapter chain, custom select / deselection behaviors. Everything is possible.

A quick overview:

• Click / Long-Click listeners
• Selection / Multi-Selection (MultiselectSample, CheckBoxSample, RadioButtonSample)
• Expandable items (ExpandableSample, IconGridSample ,AdvancedSample)
• Write less code, get better results
• Highly optimized code
• Simple Drag & Drop (SimpleItemListSample)
• Headers (StickyHeaderSample, AdvancedSample)
• Footers
• Filter (SimpleItemListSample)
• Includes suggestions from the Android Team
• Easily extensible
• Endless Scroll (EndlessScrollSample)
• "Leave-Behind"-Pattern (SwipeListSample)
• Split item view and model (ModelItem, MultiTypeModelItem)
• Chain other Adapters (SimpleItemListSample, StickyHeaderSample)
• Comes with useful Helpers
• ActionModeHelper (MultiselectSample)
• UndoHelper (MultiselectSample)
• More to come...
• FastScroller (external lib) (SimpleItemListSample)

Preview

Demo

You can try it out here Google Play (or download the latest release from GitHub)

Screenshots

Include in your project

Using Maven

The library is split up into core, commons, and extensions. The core functions are included in the following dependency.

implementation 'com.mikepenz:fastadapter:3.2.5'
implementation  'com.android.support:appcompat-v7:${latestSupportLib}'
implementation  'com.android.support:recyclerview-v7:${latestSupportLib}'

The commons package comes with some useful helpers (which are not needed in all cases) This one for example includes the FastItemAdapter

implementation 'com.mikepenz:fastadapter-commons:3.2.5'

Expandable support is included and can be added via this

implementation 'com.mikepenz:fastadapter-extensions-expandable:3.2.5'
//The tiny Materialize library used for its useful helper classes
implementation 'com.mikepenz:materialize:${latestVersion}'

Many helper classes are included in the following dependency. (This functionality also needs the Expandable extension

implementation 'com.mikepenz:fastadapter-extensions:3.2.5'
implementation  'com.android.support:design:${versions.supportLib}'
//The tiny Materialize library used for its useful helper classes
implementation 'com.mikepenz:materialize:${latestVersion}'

v3.0.x

v3 is a huge new release and comes with a big set of new changes. If you previously used the FastAdapter and head over to the MIGRATION GUIDE on how to get started with v3. In case you are searching v2.x head over here to it here.

How to use

1. Implement your item (the easy way)

Just create a class which extends the AbstractItem as shown below. Implement the methods, and your item is ready.

public class SimpleItem extends AbstractItem<SimpleItem, SimpleItem.ViewHolder> {
    public String name;
    public String description;

    //The unique ID for this type of item
    @Override
    public int getType() {
        return R.id.fastadapter_sampleitem_id;
    }

    //The layout to be used for this type of item
    @Override
    public int getLayoutRes() {
        return R.layout.sample_item;
    }

    @Override
    public ViewHolder getViewHolder(@NonNull View v) {
        return new ViewHolder(v);
    }

    /**
     * our ViewHolder
     */
    protected static class ViewHolder extends FastAdapter.ViewHolder<SimpleItem> {
        @BindView(R.id.material_drawer_name)
        TextView name;
        @BindView(R.id.material_drawer_description)
        TextView description;

        public ViewHolder(View view) {
            super(view);
            ButterKnife.bind(this, view);
        }

        @Override
        public void bindView(SimpleItem item, List<Object> payloads) {
            StringHolder.applyTo(item.name, name);
            StringHolder.applyToOrHide(item.description, description);
        }

        @Override
        public void unbindView(SimpleItem item) {
            name.setText(null);
            description.setText(null);
        }
    }
}

2. Set the Adapter to the RecyclerView

//create the ItemAdapter holding your Items
ItemAdapter itemAdapter = new ItemAdapter();
//create the managing FastAdapter, by passing in the itemAdapter
FastAdapter fastAdapter = FastAdapter.with(itemAdapter);

//set our adapters to the RecyclerView
recyclerView.setAdapter(fastAdapter);

//set the items to your ItemAdapter
itemAdapter.add(ITEMS);

3. Click listener

fastAdapter.withSelectable(true);
fastAdapter.withOnClickListener(new OnClickListener<Item>() {
    @Override
    public boolean onClick(View v, IAdapter<Item> adapter, Item item, int position) {
       // Handle click here
	return true;
    }
});

4. Click listeners for views inside your item

//just add an `EventHook` to your `FastAdapter` by implementing either a `ClickEventHook`, `LongClickEventHook`, `TouchEventHook`, `CustomEventHook`
fastItemAdapter.withEventHook(new ClickEventHook<SampleItem>() {
    
    @Nullable
    @Override
    public View onBind(@NonNull RecyclerView.ViewHolder viewHolder) {
        //return the views on which you want to bind this event
        if (viewHolder instanceof SampleItem.ViewHolder) {
            return ((ViewHolder) viewHolder).view;
        }
        return null;
    }

    @Override
    public void onClick(View v, int position, FastAdapter<SampleItem> fastAdapter, SampleItem item) {
        //react on the click event
    }
});

5. Filter

// Call this in onQueryTextSubmit() & onQueryTextChange() when using SearchView
itemAdapter.filter("yourSearchTerm");

itemAdapter.getItemFilter().withFilterPredicate(new IItemAdapter.Predicate<Item>() {
    @Override
    public boolean filter(Item item, CharSequence constraint) {
	return item.getName().startsWith(String.valueOf(constraint));
    }
});

filter() will return true to indicate which items will be removed. Returning false indicates items that will be retained.

6. Drag and drop

First, attach ItemTouchHelper to RecyclerView.

SimpleDragCallback dragCallback = new SimpleDragCallback(this);
ItemTouchHelper touchHelper = new ItemTouchHelper(dragCallback);
touchHelper.attachToRecyclerView(recyclerView);

Implement ItemTouchCallback interface in your Activity, and override the itemTouchOnMove() method.

@Override
   public boolean itemTouchOnMove(int oldPosition, int newPosition) {
       Collections.swap(fastAdapter.getAdapterItems(), oldPosition, newPosition); // change position
       fastAdapter.notifyAdapterItemMoved(oldPosition, newPosition);
       return true;
   }

7. Using different ViewHolders (like HeaderView)

Start by initializing your adapters:

// Head is a model class for your header
ItemAdapter<Header> headerAdapter = new ItemAdapter<>();

Initialize a Model FastAdapter:

ItemAdapter<IItem> itemAdapter = new ItemAdapter<>();

Finally, set the adapter:

FastAdapter fastAdapter = FastAdapter.with(headerAdapter, itemAdapter); //the order defines in which order the items will show up
recyclerView.setAdapter(fastAdapter);

8. Infinite (endless) scrolling

Create a FooterAdapter. We need this to display a loading ProgressBar at the end of our list. (Don't forget to pass it into FastAdapter.with(..))

ItemAdapter<ProgressItem> footerAdapter = new ItemAdapter<>();

Keep in mind that ProgressItem is provided by FastAdapter’s extensions.

recyclerView.addOnScrollListener(new EndlessRecyclerOnScrollListener(footerAdapter) {
    @Override
    public void onLoadMore(int currentPage) {
	footerAdapter.clear();
	footerAdapter.add(new ProgressItem().withEnabled(false));
	// Load your items here and add it to FastAdapter
	fastAdapter.add(NEWITEMS);
    }
});

For the complete tutorial and more features such as multi-select and CAB check out the sample app.

Advanced Usage

Proguard

• As of v2.5.0 there are no more known requirements to use the FastAdapter with Proguard

ExpandableItems

The FastAdapter comes with support for expandable items. After adding the dependency set up the Expandable extension via:

expandableExtension = new ExpandableExtension<>();
fastAdapter.addExtension(expandableExtension);

Expandable items have to implement the IExpandable interface, and the sub items the ISubItem interface. This allows better support. The sample app provides sample implementations of those. (Those in the sample are kept Model which allows them to be used with different parent / subitems)

As of the way how SubItems and their state are handled it is highly recommended to use the identifier based StateManagement. Just add withPositionBasedStateManagement(false) to your FastAdapter setup.

A simple item just needs to extend from the AbstractExpandableItem and provide the Parent, the ViewHolder and the SubItems it will contain as type.

public class SimpleSubExpandableItem extends AbstractExpandableItem<SimpleSubExpandableItem, SimpleSubExpandableItem.ViewHolder, SubItem> {

    /**
     * BASIC ITEM IMPLEMENTATION
     */
}

Articles

• RecyclerView Adapter made easy (FastAdapter v2.x)

Libs used in sample app:

Mike Penz:

• AboutLibraries https://github.com/mikepenz/AboutLibraries
• Android-Iconics https://github.com/mikepenz/Android-Iconics
• ItemAnimators https://github.com/mikepenz/ItemAnimators
• MaterialDrawer https://github.com/mikepenz/MaterialDrawer

Other Libs:

• Butterknife https://github.com/JakeWharton/butterknife
• Glide https://github.com/bumptech/glide
• MaterialScrollBar https://github.com/krimin-killr21/MaterialScrollBar
• StickyRecyclerHeadersAdapter https://github.com/timehop/sticky-headers-recyclerview

Developed By

• Mike Penz

  • mikepenz.com - mikepenz@gmail.com
  • paypal.me/mikepenz

• Fabian Terhorst

  • github.com/FabianTerhorst - fabian.terhorst@gmail.com
  • paypal.me/fabianterhorst

Contributors

This free, open source software was also made possible by a group of volunteers that put many hours of hard work into it. See the CONTRIBUTORS.md file for details.

Special mentions

I want to give say thanks to some special contributors who provided some huge PRs and many changes to improve this great library.

• MFlisar

License

Copyright 2017 Mike Penz

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.