imammufiid / StickyHeader

A simple lightweight sticky header ItemDecorator for RecyclerView

StickyHeader

The StickyHeader was created mainly because most popular libraries for sticky headers are too complicated or offer much more features than needed. Some of these libraries also break DiffUtils. For performance reason, a header view is created only once while view types and click listeners are not supported.

Also, by customizing this view via supplied adapter, a new sticky header will replace the previous one.

Usage

1. Add mavenCentral() to repositories block in the gradle file.
2. Add implementation 'com.github.shuhart:stickyheader:1.1.0 to the dependencies.
3. Look into the sample for additional details on how to use and configure the library.

An adapter that extends StickyAdapter is necessary for the StickyHeaderItemDecorator that is used to create and bind sticky headers:

@Override
public int getHeaderPositionForItem(int itemPosition) {
    // Return a position of a header that represents an item at adapter position.
    // For the header itself return the same itemPosition.
}

@Override
public void onBindHeaderViewHolder(RecyclerView.ViewHolder holder, int headerPosition) {
    // Update a header content here.
}

@Override
public RecyclerView.ViewHolder onCreateHeaderViewHolder(ViewGroup parent) {
    // Create a ViewHolder for a header (called only once).
}

Then, attach it to the RecyclerView:

StickyHeaderItemDecorator decorator = new StickyHeaderItemDecorator(adapter);
decorator.attachToRecyclerView(recyclerView);

How it works

• A ViewHolder is created by the adapter to reuse and bind every header.
• A header view is drawn on top of the RecyclerView using onDrawOver() callback of ItemDecoration.

License

Copyright 2018 Bogdan Kornev.

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.