RecyclerViewHeader

Super fast and easy way to create header for Android RecyclerView.

Lets you create header View for any RecyclerView that uses LinearLayoutManager, GridLayoutManager or StaggeredGridLayoutManager with just a simple method call.

Limitations

Although the library is super easy to use, it has some limitations.

RecyclerViewHeader is based on a ViewGroup being hovered over the RecyclerView (and properly shifted on scroll).

You need to bare in mind that the library is created to be used with relatively simple headers.

E.g. if your header uses a complex layout (with multiple scrolls and focusable elements) or a complicated Touch management system I advice you not to use RecyclerViewHeader, but a proper RecyclerView Adapter that incorporates inflating multiple types of views. There are other libraries on github (for example HeaderRecyclerView by Karumi) that might seem a bit more complicated to use, but are implementing mentioned approach and will fit your needs better.

Usage

For a working implementation of this library see the sample/ folder.

Basically, there are two ways of using RecyclerViewHeader.

Regular approach (super easy to use, but it uses additional Layouts so it's a bit less efficient than the second approach):

1. Create an xml layout file for your header (file can contain any type of View or ViewGroup)

```xml
<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="100dp">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="header"/>

</FrameLayout>
```

2. Create RecyclerViewHeader from xml using static initializer.

RecyclerViewHeader header = RecyclerViewHeader.fromXml(context, R.layout.header);

3. Attach RecyclerViewHeader to your RecyclerView and you're done!

RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
// set LayoutManager for your RecyclerView
header.attachTo(recyclerView);

Header-already-aligned approach (does not introduce any additional Layouts):

1. Place RecyclerViewHeaderlayout above your RecyclerView at the top part of it.

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal|top" />

    <com.bartoszlipinski.recyclerviewheader.RecyclerViewHeader
        android:id="@+id/header"
        android:layout_width="match_parent"
        android:layout_height="100dp"
        android:layout_gravity="center_horizontal|top">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="header"/>

    </com.bartoszlipinski.recyclerviewheader.RecyclerViewHeader>

</FrameLayout>

2. Get the RecyclerViewHeader view object with:

RecyclerViewHeader header = (RecyclerViewHeader) findViewById(R.id.header);

3. Attach RecyclerViewHeader to your RecyclerView (with attachTo(RecyclerView recycler, boolean headerAlreadyAligned)) and that's it.

RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
// set LayoutManager for your RecyclerView
header.attachTo(recyclerView, true);

Important notes

RecyclerViewHeader needs to be called after you've set the LayoutManager for your RecyclerView.

Current implementation of the library can be used with RecyclerViews that use LinearLayoutManager, GridLayoutManager or StaggeredGridLayoutManager.

Currently only vertical implementations of LayoutManagers are supported.

Including In Your Project

You can grab the library via Maven Central. Just add a proper dependency inside your build.gradle. Like this:

dependencies {
    compile 'com.bartoszlipinski.recyclerviewheader:library:1.2.1'
}

Developed by

• Bartosz Lipiński

License

Copyright 2015 Bartosz Lipiński

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.