Android - ListView - 分页

Android - 初心者- ListView - 分页

通常ListView 不会一下呈现大量的资料，有时候下滑到一定的资料后，会再继续加载新的页面资料，

假设第一页是100笔，当滑到第100笔，才会继续下载新的100笔。

这就是ListView的分页功能。

参考网路文章

https://blog.youkuaiyun.com/a123demi/article/details/41021513

实作最简易的版本，如下

Activity 先实作

AbsListView.OnScrollListener

这是ListView要实作覆写的两个方法，好判断是否已滑到最下面

   /**
         *   ListView 分頁功能
         */
    //底部View
    private View footerView;
    //ListView item个数
    int totalItemCount = 0;
    //最后可见的Item
    int lastVisibleItem = 0;
    //是否加载标示
    boolean isLoading = false;
    private int mPage = 1;
    private int mPageSize = 100;
    private boolean mPageEnd = false;

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        //当滑动到底端，并滑动状态为 not scrolling
        if(lastVisibleItem == totalItemCount && scrollState == SCROLL_STATE_IDLE) {
            if (!isLoading) {
                isLoading = true;
                //设置可见
                footerView.setVisibility(View.VISIBLE);
                //加载数据
                if(!mPageEnd) {
                    mPage++;
                    loadDataPage(mPage);
                }
            }
        }
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        this.lastVisibleItem = firstVisibleItem + visibleItemCount;
        this.totalItemCount = totalItemCount;
    }

并且ListView要设定方法与FooterView

        mAdapter = new MemberListAdapter(this);
        mListView.setAdapter(mAdapter);
        mListView.setOnScrollListener(this);
        LayoutInflater mInflater = LayoutInflater.from(this);
        footerView = mInflater.inflate(R.layout.layout_list_footer,null);
        footerView.setVisibility(View.GONE);
        mListView.addFooterView(footerView);

        mPage = 1;
        mPageEnd = false;
        loadDataPage(mPage);
        isLoading = false;
        mListView.setSelection(0);

loadDataPage(int page)则撰写如下

    public void loadDataPage(int page){
        mPage = page;
        MemberDao dao = MemberDao .getInstance(this);
        List<Member> list = dao.getAll(mPage,mPageSize);

        if(list.size()<mPageSize) {
            mPageEnd = true;
        }

        mAdapter.addAll(list);
        mAdapter.notifyDataSetChanged();
        footerView.setVisibility(View.GONE);
        isLoading = false;
    }

再来建立FooterView Layout

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/layout_footer"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:orientation="horizontal" >
    <ProgressBar
        style="?android:attr/progressBarStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="30dp"
        android:layout_marginTop="30dp" />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:text="正在加载..."
        android:textColor="#0000FF" />
</LinearLayout>

应该这样，就可以做好分页功能