ItemPool

Decouple the item(/nested viewholder) from recyclerview's adapter.

Reuse itemview in every recyclerview.

Setting up

• Add the JitPack repository to your project root build.gradle:

repositories {
    maven { url "https://jitpack.io" }
}

• Add the dependency to your app or lib build.gradle:

dependencies {
    compile 'com.github.nekocode:ItemPool:{lastest-version}'
}

Usage

Firstly, create a new Item class. It can help create the itemView and bind data to the view, just like the behavior of ViewHolder. It is pluggable and can be used for every ItemPool(RecyclerView). Please note that the generic type argument in class declaration define the binding data type of this item.

public class TestItem extends Item<String> {
    TextView textView;

    @NonNull
    @Override
    public View onCreateItemView(@NonNull LayoutInflater inflater, @NonNull ViewGroup parent) {
        View itemView = inflater.inflate(R.layout.item_test, parent, false);
        textView = (TextView) itemView.findViewById(R.id.textView);
        return itemView;
    }

    @Override
    public void onBindItem(@NonNull final RecyclerView.ViewHolder holder, @NonNull String s, ItemEventHandler eventHandler) {
        textView.setText(s);
    }
}

And then obtain an ItemPool instance. (You don't need to create adapter or data list. The ItemPool like a mixture of them.) The next step is to add item types (the class of item) and data to it. It will automatically select the matched item for the data element.

ItemPool items = new ItemPool();
items.addType(TestItem.class);
items.addType(TestItem2.class);

items.add(new Header());
items.add("A");
items.add("B");

items.attachTo(recyclerView);

When data changes, you can call the notify* functions just like adapter's. Such as:

items.notifyDataSetChanged();

If you want to handler the item's events such as itemView click / long click, or childView's event. You can setup an ItemEventHandler for the ItemPool:

items.onEvent(new ItemEventHandler() {
    @Override
    public void onEvent(@NonNull Class<? extends Item> clazz, @NonNull ItemEvent event) {
        if (clazz.equals(TestItem.class)) {
            switch (event.action) {
                case ItemEvent.ITEM_CLICK:
                    // Handler the event
                    break;
            }

        } else if (clazz.equals(TestItem2.class)) {
            switch (event.action) {
                case ItemEvent.ITEM_CLICK:
                    // Handler the event
                    break;

                case TestItem2.CLICK_TEXT:
                    // Handler the event
                    break;
            }
    }
});

However, it will auto trigger the ItemEvent.ITEM_CLICK and ItemEvent.ITEM_LONGCLICK events. But you should trigger childView's event manually. For example:

public class TestItem2 extends Item<Header> {
    public static final int CLICK_TEXT = 1;
    TextView textView;

    // ...

    @Override
    public void onBindItem(@NonNull final RecyclerView.ViewHolder holder, @NonNull Header header, final ItemEventHandler eventHandler) {
        textView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                eventHandler.onEvent(TestItem2.class, event(CLICK_TEXT, null));
            }
        });
    }
}

Note that

It can help you reduce a lot of code but it lose the flexibility of the recyclerview's adapter. In some cases you still need to create an adapter.

By the way, you can also try the AdapterDelegates or FastAdapter.