ListView上拉加载更多的写法

listview或者recyclerview 一般我们会用到上拉加载，或者下拉加载

/**
 * Created by Arcturis lfy on 2019/12/12.
 * <p/>
 * 上拉加载更多的listview
 * <p>Copyright 2017 新疆西北星.</p>
 */
public class LoadMoreListView extends ListView implements AbsListView.OnScrollListener  {

    private Context mContext;
    private View mFootView;
    private int mTotalItemCount;
    private OnLoadMoreListener mLoadMoreListener;
    private boolean mIsLoading=false;

    public LoadMoreListView(Context context) {
        super(context);
        init(context);
    }

    public LoadMoreListView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context);
    }

    public LoadMoreListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    private void init(Context context){
        this.mContext=context;
        mFootView= LayoutInflater.from(context).inflate(R.layout.header_view_layout,null);
        setOnScrollListener(this);
    }


    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        // 滑到顶部后自动加载，判断listview已经停止滚动并且最后可视的条目等于 0
        //举一反三这里也可以判断是不是到底部 ，这样 index就是为 总数-1
        int lastVisibleIndex = view.getLastVisiblePosition();
        int firstIndex = view.getFirstVisiblePosition();
        if (!mIsLoading
                && scrollState == OnScrollListener.SCROLL_STATE_IDLE
//                && lastVisibleIndex == mTotalItemCount-1
                && firstIndex == 0
                ) {
            mIsLoading=true;
//            addFooterView(mFootView);
            addHeaderView(mFootView);
            if (mLoadMoreListener!=null) {
                mLoadMoreListener.onloadMore();
            }
        }

    }


    @Override
    public void onScroll(AbsListView absListView, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        mTotalItemCount=totalItemCount;
        if (firstVisibleItem == 0) {
            Toast.makeText(mContext, "滑到顶部",Toast.LENGTH_SHORT).show();
        }
        if (visibleItemCount + firstVisibleItem == totalItemCount) {
            Toast.makeText(mContext, "滑到底部",Toast.LENGTH_SHORT).show();
        }


    }

    public void setOnLoadMoreListener(OnLoadMoreListener listener){
        mLoadMoreListener=listener;
    }

    public interface OnLoadMoreListener{
        void onloadMore();
    }
    public void setLoadCompleted(){
        mIsLoading=false;
//       removeFooterView(mFootView);
        removeHeaderView(mFootView);
    }

}

有一个Layout 就是Progress的在转

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal" android:layout_width="match_parent"
    android:gravity="center"
    android:padding="15dp"
    android:layout_height="match_parent">
    <ProgressBar
        style="@android:style/Widget.ProgressBar.Small"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    <TextView
        android:layout_marginLeft="10dp"
        android:text="正在加载..."
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
</LinearLayout>

那么我们怎么用呢

   mListView.setAdapter(adapter);
        mListView.setOnLoadMoreListener(new LoadMoreListView.OnLoadMoreListener() {
            @Override
            public void onloadMore() {
                loadMore();
            }
        });

 //添加到头部的写法   mData.add(0,object);即可
private void loadMore() {
        new Thread(){
            @Override
            public void run() {
                super.run();
                try {
                    Thread.sleep(2000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                mData.add(0,"111");
                mData.add(0,"222");
                mData.add(0,"333");
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        adapter.notifyDataSetChanged();
                        mListView.setLoadCompleted();
                    }
                });
            }
        }.start();
    }

这样我们就能实现上拉加载更多了！

下载加载更多未给出，大家自己改吧改吧就行了，看注释应该知道咋改了