NodeFlow is an Android library that provides a simple way to visualize hierarchical content. Perfect for displaying items that are organized in categories / subcategories.

Requirements

Android 4.0+ (Ice Cream Sandwich and later)

Using NodeFlow

Step 1

Add the following line to the dependencies section of your build.gradle file

compile 'com.telenav.nodeflow:nodeflow:0.1.2'

Step 2

Extend NodeFlowLayout class and implement abstract methods

public class MyFlow extends NodeFlowLayout {

...

    //define root node and populate it with data
    Node<String> root = Node.get("root").addChildren(Arrays.asList("child1", "child2", "child3"));

    @Override
    protected Node<?> getRootNode() {
        return root;
    }

    @Override
    protected View getContentView(Node<?> node) {
        //inflate view
        ViewGroup v = (ViewGroup) LayoutInflater.from(getContext()).inflate(R.layout.content, this, false);
        //populate with content
        ((TextView) v.findViewById(R.id.content_title)).setText(node.getData());
        return v;
    }

    @Override
    protected View getHeaderView(Node<?> node) {
        //inflate view
        ViewGroup v = (ViewGroup) LayoutInflater.from(getContext()).inflate(R.layout.header, this, false);
        //populate with content
        ((TextView) v.findViewById(R.id.list_item_text)).setText(node.getData());
        return v;
    }
}

Step 3

Add extended view to a layout

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.yourpackage.MyFlow
        android:id="@+id/nodeFlow"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</RelativeLayout>

Step 4 (Optional)

Set node change listener & animation duration

 MyFlow nodeFlow = ((MyFlow) findViewById(R.id.nodeFlow));
 nodeFlow.setNodeChangeListener(new OnActiveNodeChangeListener() {...});
 nodeFlow.setAnimationDuration(500);

Sample

For a more detailed example check the demoapp module.

License

Apache License, Version 2.0