android SwipeRefreshLayout 增加上拉加载更多
大家可能有的没有swipeRefreshLayout这个类，简单说一下，这是v4包里面的，19.1版本的时候就有了，但是当时的样式还是几个横杠，大概在21.0后吧，已经是我这个demo这样了。。挺好看的。一个圆形进度条.所以大家在使用时，请先升级一下自己的v4包,另外大家可能android support library已经是19.1以上了，还是没有，大家要注意一下，上面的Android Support Repository。更新到最新版本
1,继承SwipeRefreshLayout，自定义一个view VRefresh
package demo.veidy.com.veidydemolist;
import android.content.Context;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.widget.AbsListView;
import android.widget.ListView;
/**
* Created by veidy on 2015/1/16.
*/
public class VRefresh extends SwipeRefreshLayout implements AbsListView.OnScrollListener {
/**
* 滑动到最下面时的上拉操作
*/
private int mTouchSlop;
/**
* listview实例
*/
private ListView mListView;
/**
* RecyclerView 实例
*/
private RecyclerView recyclerView;
/**
* 上拉监听器, 到了最底部的上拉加载操作
*/
private OnLoadListener mOnLoadListener;
/**
* ListView的加载中footer
*/
private View mFooterView;
/**
* 按下时的y坐标
*/
private int mYDown;
/**
* 抬起时的y坐标, 与mYDown一起用于滑动到底部时判断是上拉还是下拉
*/
// private int mLastY;
/**
* 是否在加载中 ( 上拉加载更多 )
*/
private boolean isLoading = false;
private float mLastY = -1;
/**
* 最后一行
*/
boolean isLastRow = false;
/**
* 是否还有数据可以加载
*/
private boolean moreData = true;
public VRefresh(Context context) {
super(context);
}
public VRefresh(Context context, AttributeSet attrs) {
super(context, attrs);
mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();
mFooterView = LayoutInflater.from(context).inflate(R.layout.vrefresh_footer, null, false);
}
/**
* 设置默认的childview-必须要设置
*
* @param context
* @param childView
*/
public void setView(Context context, View childView) {
if (childView instanceof ListView) {
mListView = (ListView) childView;
// 设置滚动监听器给ListView, 使得滚动的情况下也可以自动加载
mListView.setOnScrollListener(this);
mListView.setFooterDividersEnabled(false);
Log.d("VRefresh", "获取到listview");
} else if (childView instanceof RecyclerView) {
recyclerView = (RecyclerView) childView;
// 设置滚动监听器给ListView, 使得滚动的情况下也可以自动加载
recyclerView.setOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
Log.d("VRefresh", "dx=" + dx + "---dy=" + dy);
}
});
Log.d("VRefresh", "获取到recyclerView");
}
initWithContext(context);
}
private void initWithContext(Context context) {
if (mListView != null)
mListView.addFooterView(mFooterView, null, false);//设置footview不可点击
// if (recyclerView!=null){
// Log.d("VRefresh","快去自定义recyclerView 加footview吧");
// return;
// }
mFooterView.setVisibility(View.GONE);//默认先隐藏
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
}
/**
* 是否可以加载更多, listview不在加载中, 且为上拉操作.
*
* @param canload 是否还有可以加载的数据
* @return
*/
private boolean canLoad(boolean canload) {
return canload && !isLoading && isPullUp();
}
/**
* 判断是否到了最底部
*/
private boolean isBottom() {
if (mListView != null && mListView.getAdapter() != null) {
return mListView.getLastVisiblePosition() == (mListView.getAdapter().getCount() - 1);
}
return false;
}
/**
* 是否是上拉操作
*
* @return
*/
private boolean isPullUp() {
Log.d("VRefresh", "isPullUp--->");
return (mYDown - mLastY) >= mTouchSlop;
}
/**
* 如果到了最底部,而且是上拉操作.onLoadMore
*/
private void loadData() {
Log.d("VRefresh", "loadData--->");
if (mOnLoadListener != null) {
// 设置状态
setLoading(true);
mOnLoadListener.onLoadMore();
}
}
/**
* @param loading
*/
public void setLoading(boolean loading) {
isLoading = loading;
if (isLoading) {
// mListView.addFooterView(mFooterView);
mFooterView.setVisibility(View.VISIBLE);
} else {
// mListView.removeFooterView(mFooterView);
mFooterView.setVisibility(View.GONE);
mYDown = 0;
mLastY = 0;
}
}
/*
* (non-Javadoc)
* @see android.view.ViewGroup#dispatchTouchEvent(android.view.MotionEvent)
*/
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
final int action = event.getAction();
if (mLastY == -1) {
mLastY = (int) event.getRawY();
}
switch (action) {
case MotionEvent.ACTION_DOWN:
// 按下
mYDown = (int) event.getRawY();
Log.d("VRefresh", "按下");
break;
case MotionEvent.ACTION_MOVE:
// 移动
mLastY = (int) event.getRawY();
final float deltaY = event.getRawY() - mLastY;
Log.d("VRefresh", "移动");
// if (null != mListView && isPullUp()) {
// if (mListView.getLastVisiblePosition() == mTotalItemCount - 1 || deltaY < 0) {
// mListView.setSelection(mTotalItemCount - 1);
// }
// }
break;
default:
// if (isLastRow && canLoad(moreData)) {
// Log.d("VRefresh", "能加载...");
// loadData();
// } else {
// Log.d("VRefresh", "不能加载...");
// }
break;
}
return super.dispatchTouchEvent(event);
}
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
/**
* @param loadListener
*/
public void setOnLoadListener(OnLoadListener loadListener) {
mOnLoadListener = loadListener;
}
@Override
public void onScrollStateChanged(AbsListView absListView, int i) {
}
@Override
public void onScroll(AbsListView absListView, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
//判断是否滚到最后一行
if (firstVisibleItem + visibleItemCount == totalItemCount && totalItemCount > 0) {
//双重判断，应该没有必要
if (absListView.getLastVisiblePosition() == (absListView.getAdapter().getCount() - 1)) {
isLastRow = true;
// mFooterView.setVisibility(View.VISIBLE);
if (canLoad(moreData)) {
Log.d("VRefresh", "滚动到最后一行,加载数据，显示footview");
loadData();
}
}
Log.d("VRefresh", "滚动到最后一行");
} else {
Log.d("VRefresh", "没有滚动到最后一行");
isLastRow = false;
}
}
public static interface OnLoadListener {
public void onLoadMore();
}
public boolean isMoreData() {
return moreData;
}
public void setMoreData(boolean moreData) {
this.moreData = moreData;
}
}
2.创建一个activity--SwipeRefreshDemo,创建activity之前,创建一个xml布局,直接引用自定义控制
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin" > <demo.veidy.com.veidydemolist.VRefresh android:id="@+id/swiperefreshlayou" android:layout_width="match_parent" android:layout_height="match_parent"> <ListView android:id="@+id/lv" android:layout_width="match_parent" android:layout_height="match_parent"> </ListView> </demo.veidy.com.veidydemolist.VRefresh> </RelativeLayout>
3,在activity里面进行设置-核心代码
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_swipe_refresh_layout_view);
initialize();
for (int i = 0; i < 2; i++) {
A a = new A();
a.setDescribe("----" + i);
bean.add(a);
}
//进度条颜色
swiperefreshlayou.setColorSchemeResources(android.R.color.holo_red_light,android.R.color.holo_green_light, android.R.color.holo_blue_bright, android.R.color.holo_orange_light);
// swiperefreshlayou.setProgressBackgroundColor(getResources().getColor(android.R.color.holo_red_light));
swiperefreshlayou.setSize(0);//0和1 圆形进度条两种不同效果 0刚开始有渲染效果
myAdapter = new MyAdapter(bean, this);//listview adapter
swiperefreshlayou.setView(this, lv);//设置嵌套的子view -listview
swiperefreshlayou.setMoreData(false);//设置是否还有数据可加载(一般根据服务器反回来决定)
lv.setAdapter(myAdapter);
swiperefreshlayou.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
Message msg = mhandler.obtainMessage();
msg.what = REFRESH_COMPLETE;
mhandler.sendMessageDelayed(msg, 3000);//3秒后通知停止刷新
}
});
swiperefreshlayou.setOnLoadListener(new VRefresh.OnLoadListener() {
@Override
public void onLoadMore() {
Message msg = mhandler.obtainMessage();
msg.what = LOADMORE_COMPLETE;
mhandler.sendMessageDelayed(msg, 3000);//3秒后通知停止加载更多
}
});
}
加载完成后去handle更新
private static final int REFRESH_COMPLETE = 0;//刷新完成标识
private static final int LOADMORE_COMPLETE = 1;//加载更多完成标识
Handler mhandler = new Handler() {
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what) {
case LOADMORE_COMPLETE:
for (int i = 0; i < 5; i++) {
A a = new A();
a.setDescribe("----" + i);
bean.add(a);
}
myAdapter.notifyDataSetChanged();
swiperefreshlayou.setMoreData(true);//设置还有数据可以加载
swiperefreshlayou.setLoading(false);//停止加载更多
break;
case REFRESH_COMPLETE:
bean.clear();
for (int i = 0; i < 5; i++) {
A a = new A();
a.setDescribe("----" + i);
bean.add(a);
}
swiperefreshlayou.setMoreData(true);//设置还有数据可以加载
myAdapter.notifyDataSetChanged();
swiperefreshlayou.setRefreshing(false);//停止刷新
break;
}
}
};