Example Layer Conversation Adapter

conversation-adapter.java

package com.layer.sample.adapters;

import android.database.DataSetObserver;
import android.net.Uri;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Adapter;

import com.layer.sdk.LayerChange;
import com.layer.sdk.LayerChangeEvent;
import com.layer.sdk.LayerChangeEventListener;
import com.layer.sdk.LayerClient;
import com.layer.sdk.exceptions.NotAuthenticatedException;
import com.layer.sdk.exceptions.PersistenceClosedException;
import com.layer.sdk.messaging.Conversation;

import java.util.concurrent.ConcurrentLinkedQueue;

public abstract class LayerConversationsAdapter implements Adapter, LayerChangeEventListener.MainThread {
    private ConcurrentLinkedQueue<DataSetObserver> mDataSetObservers = new ConcurrentLinkedQueue<DataSetObserver>();
    final OrderedIds mIds = new OrderedIds();

    private LayerClient mClient;
    private Options mOptions;

    public LayerConversationsAdapter(LayerClient client, Options options) {
        mClient = client;
        mOptions = (options == null) ? new DefaultOptions() : options;
        refresh();
    }

    public void refresh() {
        mIds.clear();
        try {
            int i = 0;
            for (Uri uri : mClient.getConversationIds()) {
                mIds.append(i++, uri);
            }
        } catch (NotAuthenticatedException e) {
        } catch (PersistenceClosedException e) {
        }

        notifyDataSetChanged();
    }

    public void notifyDataSetChanged() {
        for (DataSetObserver observer : mDataSetObservers) {
            observer.onChanged();
        }
    }


    //=================================
    // Options
    //=================================
    public static class Options {
        boolean mIsUpdateOnMessage;

        public Options() {
        }

        public Options setIsUpdateOnMessage(boolean isUpdateOnMessage) {
            mIsUpdateOnMessage = isUpdateOnMessage;
            return this;
        }

        public boolean isUpdateOnMessage() {
            return mIsUpdateOnMessage;
        }
    }

    public static class DefaultOptions extends Options {
        @Override
        public boolean isUpdateOnMessage() {
            return true;
        }
    }


    //=================================
    // Listener
    //=================================
    @Override
    public void onEventMainThread(LayerChangeEvent event) {
        // TODO: update index from 0 to lastMessageDate when implemented.
        boolean isChange = false;
        for (LayerChange change : event.getChanges()) {
            switch (change.getObjectType()) {
                case CONVERSATION:
                    Conversation conversation = (Conversation) change.getObject();
                    isChange = true;
                    switch (change.getChangeType()) {
                        case INSERT:
                            mIds.insert(0, conversation.getId());
                            break;

                        case UPDATE:
                            if (change.getAttributeName().equals("id")) {
                                Uri oldId = (Uri) change.getOldValue();
                                Uri newId = (Uri) change.getNewValue();
                                mIds.update(oldId, newId, 0);
                            }
                            break;

                        case DELETE:
                            mIds.delete(conversation.getId());
                            break;
                    }
                    break;

                case MESSAGE:
                    if (mOptions.isUpdateOnMessage()) {
                        isChange = true;
                    }
                    break;
            }
        }

        // Update UI?
        if (isChange) {
            notifyDataSetChanged();
        }
    }


    //=================================
    // Adapter
    //=================================
    @Override
    public int getCount() {
        return mIds.size();
    }

    @Override
    public Conversation getItem(int position) {
        try {
            return mClient.getConversation(mIds.getId(position));
        } catch (NotAuthenticatedException e) {
            return null;
        } catch (PersistenceClosedException e) {
            return null;
        }
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public abstract View getView(int position, View convertV, ViewGroup viewGroup);

    @Override
    public abstract int getItemViewType(int position);

    @Override
    public abstract int getViewTypeCount();

    @Override
    public boolean isEmpty() {
        return mIds.isEmpty();
    }

    @Override
    public void registerDataSetObserver(DataSetObserver dataSetObserver) {
        if (!mDataSetObservers.contains(dataSetObserver)) {
            mDataSetObservers.add(dataSetObserver);
        }
    }

    @Override
    public void unregisterDataSetObserver(DataSetObserver dataSetObserver) {
        mDataSetObservers.remove(dataSetObserver);
    }
}