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