android - 带有 Koush ion 的 Android 无尽滚动

Question

我对无尽的滚动ListView和 Koush-ion 库有疑问。问题是如果没有第一个离子请求，无限滚动就无法工作。我的代码：

    @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_news);

    newsList = new ArrayList<>();

    initViews();
    setAdapter();
    ionGetNews(1); //if comment this line listView will be empty.
    listViewNews.setOnScrollListener(new EndlessScrollListener() {
        @Override
        public void onLoadMore(int page, int totalItemsCount) {
            Log.d("Scroll_page", page + "");
            //ionGetNews(page);
            Toast.makeText(NewsActivity.this, page + "", Toast.LENGTH_SHORT).show();
        }
    });
}

private void initViews() {
    listViewNews = (ListView) findViewById(R.id.listViewNews);
}

private void setAdapter() {
    adapterNews = new AdapterNews(NewsActivity.this, newsList);
    listViewNews.setAdapter(adapterNews);
}

private void ionGetNews(int page) {
    JsonObject jo = new JsonObject();
    jo.addProperty("page", page);
    jo.addProperty("type", 0);
    jo.addProperty("favourite_shop", 0);

    Log.d("Json_info", jo.toString());

    Ion.with(NewsActivity.this)
            .load(Constants.POST, Constants.BASE_URL + Constants.NEWS)
            .setJsonObjectBody(jo)
            .asJsonArray()
            .setCallback(new FutureCallback<JsonArray>() {
                @Override
                public void onCompleted(Exception e, JsonArray result) {
                    if (e != null) {

                    }
                    if (result != null) {
                        newsParseJson(result);
                    } else {

                    }
                }
            });
}

    private void newsParseJson(JsonArray array) {
    Gson gson = new Gson();
    Type listType = new TypeToken<List<News>>() {
    }.getType();
    List<News> newses = (List<News>) gson.fromJson(array, listType);
    newsList.addAll(newses);
    adapterNews.notifyDataSetChanged();
    listViewNews.setVisibility(View.VISIBLE);

    Log.d("NewsList", newses.toString());
}

EndlessScrollListener 类：

public abstract class EndlessScrollListener implements AbsListView.OnScrollListener {
    // The minimum amount of items to have below your current scroll position
    // before loading more.
    private int visibleThreshold = 15;
    // The current offset index of data you have loaded
    private int currentPage = 1;
    // The total number of items in the dataset after the last load
    private int previousTotalItemCount = 0;
    // True if we are still waiting for the last set of data to load.
    private boolean loading = true;
    // Sets the starting page index
    private int startingPageIndex = 0;

    public EndlessScrollListener() {
    }

    public EndlessScrollListener(int visibleThreshold) {
        this.visibleThreshold = visibleThreshold;
    }

    public EndlessScrollListener(int visibleThreshold, int startPage) {
        this.visibleThreshold = visibleThreshold;
        this.startingPageIndex = startPage;
        this.currentPage = startPage;
    }

    // This happens many times a second during a scroll, so be wary of the code you place here.
    // We are given a few useful parameters to help us work out if we need to load some more data,
    // but first we check if we are waiting for the previous load to finish.
    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)
    {
        // If the total item count is zero and the previous isn't, assume the
        // list is invalidated and should be reset back to initial state
        if (!loading && (totalItemCount < previousTotalItemCount)) {
            this.currentPage = this.startingPageIndex;
            this.previousTotalItemCount = totalItemCount;
            if (totalItemCount == 0) { this.loading = true; }
        }
        // If it’s still loading, we check to see if the dataset count has
        // changed, if so we conclude it has finished loading and update the current page
        // number and total item count.
        if (loading && (totalItemCount > previousTotalItemCount)) {
            loading = false;
            previousTotalItemCount = totalItemCount;
            currentPage++;
        }

        // If it isn’t currently loading, we check to see if we have breached
        // the visibleThreshold and need to reload more data.
        // If we do need to reload some more data, we execute onLoadMore to fetch the data.
        if (!loading && (totalItemCount - visibleItemCount)<=(firstVisibleItem + visibleThreshold)) {
            onLoadMore(currentPage + 1, totalItemCount);
            loading = true;
        }
    }

    // Defines the process for actually loading more data based on page
    public abstract void onLoadMore(int page, int totalItemsCount);

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        // Don't take any action on changed
    }
}

我做错了什么？如何解决这个问题呢？