支持上拉加载更多的recyclerView
对于下滑更新，谷歌给了个自己的控件，在v4包里，叫SwipeProgressBar，但其实并不好用，上拉加载更多这个功能谷歌直接就不管了，网上有一些用SwipeProgressBar实现的案例，但是效果都不好，所以我仿ListView上滑加载更多的思路给recyclerView用同样方法实现上拉加载。
特性：
下拉到底并且继续上拉超过一定高度后，松手才会开始刷新
松手后有回弹效果
如果没有达到指定高度，也会自动回弹
上拉超过一定高度，但是不松手，放回原来的位置，不会触发刷新
效果图：
首先是自定义一个recyclerView，重点是在里面加入一个滚动监听，代码如下
import android.content.Context;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import com.imaginato.qravedconsumer.utils.JLogUtils;
/**
* Created by Administrator on 2016/1/27.
*/
public class CustomListRecyclerView extends RecyclerView{
private float mLastY = -1; // save event y
private int footerHeight = -1;
// -- footer view
private CustomDragRecyclerFooterView mFooterView;
private boolean mEnablePullLoad;
private boolean mPullLoading;
private boolean isBottom;
private boolean mIsFooterReady = false;
private boolean mIsInertia = false;
private LoadMoreListener loadMoreListener;
// total list items, used to detect is at the bottom of listview.
// for mScroller, scroll back from header or footer.
private int mScrollBack;
private final static int SCROLLBACK_FOOTER = 1;
private final static int SCROLL_DURATION = 400; // scroll back duration
private final static int PULL_LOAD_MORE_DELTA = 50; // when pull up >= 50px
// at bottom, trigger
// load more.
private final static float OFFSET_RADIO = 1.8f; // support iOS like pull
// feature.
private OnClickListener footerClickListener;
public CustomListRecyclerView(Context context) {
super(context);
initView(context);
}
public CustomListRecyclerView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
}
public CustomListRecyclerView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initView(context);
}
private void updateFooterHeight(float delta) {
if(mFooterView==null)return;
if(delta>60)delta = delta/4;
if(delta>20)delta = delta/2;
// Log.i("Alex2","delta是"+delta);
int height = mFooterView.getBottomMargin() + (int) delta;
if (mEnablePullLoad && !mPullLoading) {
if (height > 200){
mFooterView.setState(CustomDragFooterView.STATE_READY);
mIsFooterReady = true;
// Log.i("Alex2", "ready");
} else {
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
mIsFooterReady = false;
// Log.i("Alex2", "nomal");
}
}
mFooterView.setBottomMargin(height);
}
private void resetFooterHeight() {
int bottomMargin = mFooterView.getBottomMargin()-20;
if (-bottomMargin < 0) {
mScrollBack = SCROLLBACK_FOOTER;
Log.i("Alex2", "准备重置高度,margin是" + bottomMargin + "自高是" + footerHeight);
this.smoothScrollBy(0,-bottomMargin);
//一松手就立即开始加载
if(mIsFooterReady){
startLoadMore();
}
}
}
public void setLoadMoreListener(LoadMoreListener listener){
this.loadMoreListener = listener;
}
public void initView(Context context){
final LinearLayoutManager layoutManager = new LinearLayoutManager(context);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
this.setLayoutManager(layoutManager);
this.footerClickListener = new footerViewClickListener();
this.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
switch (newState){
case RecyclerView.SCROLL_STATE_IDLE:
Log.i("Alex2", "停下了||放手了");
if(isBottom)resetFooterHeight();
break;
case RecyclerView.SCROLL_STATE_DRAGGING:
Log.i("Alex2", "开始拖了,现在margin是" + (mFooterView == null ? "" : mFooterView.getBottomMargin()));
break;
case RecyclerView.SCROLL_STATE_SETTLING:
Log.i("Alex2", "开始惯性移动");
break;
}
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int lastItemPosition = layoutManager.findLastVisibleItemPosition();
Log.i("Alex2","mEnable是"+mEnablePullLoad+"lastitemPosition是"+lastItemPosition+" itemcount是"+layoutManager.getItemCount());
if(lastItemPosition == layoutManager.getItemCount()-1 && mEnablePullLoad) {
isBottom = true;
mFooterView = (CustomDragRecyclerFooterView)layoutManager.findViewByPosition(layoutManager.findLastVisibleItemPosition());//一开始还不能hide，因为hide得到最后一个可见的就不是footerview了
Log.i("Alex2","到底啦！！"+"mfooterView是"+mFooterView);
if(mFooterView!=null) mFooterView.setOnClickListener(footerClickListener);
if(footerHeight==-1 && mFooterView!=null){
mFooterView.show();
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
footerHeight = mFooterView.getMeasuredHeight();//这里的测量一般不会出问题
Log.i("Alex2", "底部高度为" + footerHeight);
}
updateFooterHeight(dy);
}else {
isBottom = false;
}
}
});
}
/**
* enable or disable pull up load more feature.
*
* @param enable
*/
public void setPullLoadEnable(boolean enable) {
mPullLoading = false;
mEnablePullLoad = enable;
if(mFooterView==null)return;
if (!mEnablePullLoad) {
// this.smoothScrollBy(0,-footerHeight);
mFooterView.hide();
mFooterView.setOnClickListener(null);
mFooterView.setBottomMargin(0);
//make sure "pull up" don't show a line in bottom when listview with one page
} else {
mFooterView.show();
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
mFooterView.setVisibility(VISIBLE);
//make sure "pull up" don't show a line in bottom when listview with one page
// both "pull up" and "click" will invoke load more.
mFooterView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startLoadMore();
}
});
}
}
/**
* stop load more, reset footer view.
*/
public void stopLoadMore() {
if (mPullLoading == true) {
mPullLoading = false;
mFooterView.show();
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
}
}
private void startLoadMore() {
mPullLoading = true;
mFooterView.setState(CustomDragFooterView.STATE_LOADING);
Log.i("Alex2", "现在开始加载");
mIsFooterReady = false;
if (loadMoreListener != null) {
loadMoreListener.onLoadMore();
}
}
/**
* 在刷新时要执行的方法
*/
public interface LoadMoreListener{
public void onLoadMore();
}
/**
* 点击loadMore后要执行的事件
*/
class footerViewClickListener implements OnClickListener {
@Override
public void onClick(View v) {
startLoadMore();
}
}
}
然后是底部的自定义View，我这里是一个LinearLayout
import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.qraved.app.R;
public class CustomDragRecyclerFooterView extends LinearLayout {
public final static int STATE_NORMAL = 0;
public final static int STATE_READY = 1;
public final static int STATE_LOADING = 2;
private Context mContext;
private View mContentView;
private View mProgressBar;
private TextView mHintView;
public CustomDragRecyclerFooterView(Context context) {
super(context);
initView(context);
}
public CustomDragRecyclerFooterView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
}
public void setState(int state) {
mHintView.setVisibility(View.INVISIBLE);
mProgressBar.setVisibility(View.INVISIBLE);
mHintView.setVisibility(View.INVISIBLE);
if (state == STATE_READY) {
mHintView.setVisibility(View.VISIBLE);
mHintView.setText(R.string.xlistview_footer_hint_ready);
} else if (state == STATE_LOADING) {
mProgressBar.setVisibility(View.VISIBLE);
} else {
mHintView.setVisibility(View.VISIBLE);
mHintView.setText(R.string.xlistview_footer_hint_normal);
}
}
public void setBottomMargin(int height) {
if (height < 0) return ;
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
lp.bottomMargin = height;
mContentView.setLayoutParams(lp);
}
public int getBottomMargin() {
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
return lp.bottomMargin;
}
/**
* normal status
*/
public void normal() {
mHintView.setVisibility(View.VISIBLE);
mProgressBar.setVisibility(View.GONE);
}
/**
* loading status
*/
public void loading() {
mHintView.setVisibility(View.GONE);
mProgressBar.setVisibility(View.VISIBLE);
}
/**
* hide footer when disable pull load more
*/
public void hide() {
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
lp.height = 1;//这里如果设为0那么layoutManger就会抓不到
mContentView.setLayoutParams(lp);
mContentView.setBackgroundColor(Color.BLACK);//这里的颜色要和自己的背景色一致
}
/**
* show footer
*/
public void show() {
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
lp.height = LayoutParams.WRAP_CONTENT;
lp.width = LayoutParams.MATCH_PARENT;
mContentView.setLayoutParams(lp);
mContentView.setBackgroundColor(Color.WHITE);//这里的颜色要和自己的背景色一致
}
private void initView(Context context) {
mContext = context;
this.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));//recyclerView里不加这句话的话宽度就会不够
LinearLayout moreView = (LinearLayout)LayoutInflater.from(mContext).inflate(R.layout.layout_customdragfooterview, null);
addView(moreView);
moreView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
mContentView = moreView.findViewById(R.id.rlContentView);
mProgressBar = moreView.findViewById(R.id.pbContentView);
mHintView = (TextView)moreView.findViewById(R.id.ctvContentView);
}
}
顺便把自定义的布局也贴出来
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:imaginato="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:id="@+id/rlContentView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp">
<ProgressBar
android:id="@+id/pbContentView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:visibility="invisible" />
<TextView
android:id="@+id/ctvContentView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:textSize="13sp"
/>
</RelativeLayout>
<View
android:id="@+id/line"
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#CCCCCC"
android:visibility="gone" />
</LinearLayout>
最最重要的是适配器的写法，这里我考虑了一个recyclerView有头部，有中间很多item，还有显示loadmore的脚部，对应三个ViewHolder，下面给出一个适配器的案例
public class EventDetailAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
private static final int TYPE_HEADER = 0;
private static final int TYPE_ITEM = 1;
private static final int TYPE_FOOTER = 2;
private final int HEADER = 0;
private final int ITEM = 0;
boolean loadMore;
int restraurantCount;
public EventDetailAdapter(){
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_ITEM) {
//inflate your layout and pass it to view holder
View itemView = LayoutInflater.from(parent.getContext()).inflate(ITEM,null);
return new VHItem(itemView);
} else if (viewType == TYPE_HEADER) {
//inflate your layout and pass it to view holder
View headerView = LayoutInflater.from(parent.getContext()).inflate(HEADER,null);
return new VHHeader(headerView);
} else if(viewType==TYPE_FOOTER){
CustomDragRecyclerFooterView footerView = new CustomDragRecyclerFooterView(parent.getContext());
return new VHFooter(footerView);
}
throw new RuntimeException("there is no type that matches the type " + viewType + " + make sure your using types correctly");
}
public void setPullLoadMoreEnable(boolean enable){
this.loadMore = enable;
}
public boolean getPullLoadMoreEnable(){return loadMore;}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {//相当于getView
Log.i("Alex","正在绑定"+position+" "+holder);
if (holder instanceof VHItem) {
//cast holder to VHItem and set data
initItemView((VHItem) holder,restaurants.get(position-1),position);
}else if (holder instanceof VHHeader) {
//cast holder to VHHeader and set data for header.
}else if(holder instanceof VHFooter){
if(!loadMore)((VHFooter)holder).footerView.hide();//第一次初始化显示的时候要不要显示footerView
}
}
@Override
public int getItemCount() {
return restaurants==null?1:restaurants.size() + 2;
}//这里要考虑到头尾部，多以要加2
/**
* 根据位置判断这里该用哪个ViewHolder
* @param position
* @return
*/
@Override
public int getItemViewType(int position) {
if (isPositionHeader(position))return TYPE_HEADER;
else if(isPositonFooter(position))return TYPE_FOOTER;
return TYPE_ITEM;
}
/**
* 根据position判断现在是不是头部
* @param position
* @return
*/
private boolean isPositionHeader(int position) {
return position == 0;
}
private boolean isPositonFooter(int position){//这里的position从0算起
if(restaurants==null && position==1)return true;
return position==restaurants.size()+1;
}
class VHItem extends RecyclerView.ViewHolder {
RelativeLayout rlRestaurantImage;
ImageView iv_restarantImage,iv_start1,iv_start2,iv_start3,iv_start4,iv_start5;
LinearLayout llBookNow,ll_off;
List<ImageView>starsList = new ArrayList<ImageView>();
CustomTextView tv_reviewNum,tv_detail,tv_distance,tv_restarantName,tv_off;
View itemView,v_divider;
public VHItem(View itemView) {
super(itemView);
rlRestaurantImage = (RelativeLayout)itemView.findViewById(R.id.rlRestaurantImage);
iv_restarantImage = (ImageView)itemView.findViewById(R.id.iv_restarantImage);
llBookNow = (LinearLayout)itemView.findViewById(R.id.llBookNow);
iv_start1 = (ImageView)itemView.findViewById(R.id.iv_start1);
iv_start2 = (ImageView)itemView.findViewById(R.id.iv_start2);
iv_start3 = (ImageView)itemView.findViewById(R.id.iv_start3);
iv_start4 = (ImageView)itemView.findViewById(R.id.iv_start4);
iv_start5 = (ImageView)itemView.findViewById(R.id.iv_start5);
tv_reviewNum = (CustomTextView)itemView.findViewById(R.id.tv_reviewNum);
tv_detail = (CustomTextView)itemView.findViewById(R.id.tv_detail);
tv_distance = (CustomTextView)itemView.findViewById(R.id.tv_distance);
tv_restarantName = (CustomTextView)itemView.findViewById(R.id.tv_restarantName);
v_divider = itemView.findViewById(R.id.v_divider);
starsList.add(iv_start1);starsList.add(iv_start2);starsList.add(iv_start3);starsList.add(iv_start4);starsList.add(iv_start5);
ll_off = (LinearLayout)itemView.findViewById(R.id.ll_off);
tv_off = (CustomTextView)itemView.findViewById(R.id.tv_off);
}
public View getItemView(){return itemView;}
}
class VHHeader extends RecyclerView.ViewHolder {
public VHHeader(View headerView) {
super(headerView);
}
}
class VHFooter extends RecyclerView.ViewHolder {
CustomDragRecyclerFooterView footerView;
public VHFooter(View itemView) {
super(itemView);
footerView = (CustomDragRecyclerFooterView)itemView;
}
}
private void initItemView(VHItem holder,EventDetailRestaurantEntity restaurant,int posion){
if(restaurants==null||restaurants.size()==0){//如果没有restaurant
if(holder.getItemView()!=null)holder.getItemView().setVisibility(View.GONE);
return;
}
holder.tv_reviewNum.setText(restaurant.getRatingCount()+"");
holder.tv_detail.setText(EventProducer.generateDetail(holder.tv_detail.getContext(),restaurant));//计算价格区间
holder.tv_distance.setText(EventProducer.calculateDistance(holder.tv_distance.getContext(), restaurant));
holder.tv_restarantName.setText(restaurant.getTitle()+"");
}
private void initHeaderView(final VHHeader holder) {
}
}
调用方法：
EventDetailAdapter adapter;
adapter = new EventDetailAdapter(banner,restaurants,true);recyclerView.setPullLoadEnable(true);
recyclerView.setLoadMoreListener(new LoadMoreListener{
@Override
public void onLoadMore() {
JLogUtils.i("Alex","执行onLoadMore方法");
}
});
根据上面的原理，可以把recyclerView控件，adapter和footerVIew整合到一个类当中去，方便开发的时候调用，如下
底下这个类具备如下特性：
1、封装了LayoutManager，不要再在外面设置了。
2、内置了FooterVIew及其控制逻辑。
3、给这个recyclerView设置的适配器要用这个recycler里封装好的AlxDragRecyclerViewAdapter，泛型是list的元素。继承这个抽象类，并在这个抽象类的内部写类继承ViewHolder，然后在set...ViewHolder方法中实例化自定义Viewholder，在构造函数中传入布局的id，如果没有头部就把头部的id传0，并且让setHeaderViewHolder方法返回null
import android.content.Context;
import android.graphics.Color;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.qraved.app.R;
import java.util.List;
/**
* Created by Administrator on 2016/1/27.
*/
public class CustomDragRecyclerView extends RecyclerView{
private int footerHeight = -1;
// -- footer view
private CustomDragRecyclerFooterView mFooterView;
private boolean mEnablePullLoad;
private boolean mPullLoading;
private boolean isBottom;
private boolean mIsFooterReady = false;
private LoadMoreListener loadMoreListener;
private AlxDragRecyclerViewAdapter adapter;
// total list items, used to detect is at the bottom of listview.
// for mScroller, scroll back from header or footer.
private int mScrollBack;
private final static int SCROLLBACK_FOOTER = 1;
private final static int SCROLL_DURATION = 400; // scroll back duration
private final static int PULL_LOAD_MORE_DELTA = 50; // when pull up >= 50px
// at bottom, trigger
// load more.
private final static float OFFSET_RADIO = 1.8f; // support iOS like pull
// feature.
private View.OnClickListener footerClickListener;
public CustomDragRecyclerView(Context context) {
super(context);
initView(context);
}
public CustomDragRecyclerView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
}
public CustomDragRecyclerView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initView(context);
}
public void setAdapter(AlxDragRecyclerViewAdapter adapter){
super.setAdapter(adapter);
this.adapter = adapter;
}
private void updateFooterHeight(float delta) {
if(mFooterView==null)return;
if(delta>60)delta = delta/4;
if(delta>20)delta = delta/2;
// Log.i("Alex2","delta是"+delta);
int height = mFooterView.getBottomMargin() + (int) delta;
if (mEnablePullLoad && !mPullLoading) {
if (height > 150){
mFooterView.setState(CustomDragFooterView.STATE_READY);
mIsFooterReady = true;
// Log.i("Alex2", "ready");
} else {
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
mIsFooterReady = false;
// Log.i("Alex2", "nomal");
}
}
mFooterView.setBottomMargin(height);
}
private void resetFooterHeight() {
int bottomMargin = mFooterView.getBottomMargin()-20;
if (-bottomMargin < 0) {
mScrollBack = SCROLLBACK_FOOTER;
Log.i("Alex2", "准备重置高度,margin是" + bottomMargin + "自高是" + footerHeight);
this.smoothScrollBy(0,-bottomMargin);
//一松手就立即开始加载
if(mIsFooterReady){
startLoadMore();
}
}
}
public void setLoadMoreListener(LoadMoreListener listener){
this.loadMoreListener = listener;
}
public void initView(Context context){
final LinearLayoutManager layoutManager = new LinearLayoutManager(context);//自带layoutManager，请勿设置
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
this.setLayoutManager(layoutManager);
this.footerClickListener = new footerViewClickListener();
this.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
switch (newState){
case RecyclerView.SCROLL_STATE_IDLE:
Log.i("Alex2", "停下了||放手了");
if(isBottom)resetFooterHeight();
break;
case RecyclerView.SCROLL_STATE_DRAGGING:
Log.i("Alex2", "开始拖了,现在margin是" + (mFooterView == null ? "" : mFooterView.getBottomMargin()));
break;
case RecyclerView.SCROLL_STATE_SETTLING:
Log.i("Alex2", "开始惯性移动");
break;
}
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int lastItemPosition = layoutManager.findLastVisibleItemPosition();
Log.i("Alex2","mEnable是"+mEnablePullLoad+"lastitemPosition是"+lastItemPosition+" itemcount是"+layoutManager.getItemCount());
if(lastItemPosition == layoutManager.getItemCount()-1 && mEnablePullLoad) {
isBottom = true;
mFooterView = (CustomDragRecyclerFooterView)layoutManager.findViewByPosition(layoutManager.findLastVisibleItemPosition());//一开始还不能hide，因为hide得到最后一个可见的就不是footerview了
Log.i("Alex2","到底啦！！"+"mfooterView是"+mFooterView);
if(mFooterView!=null) mFooterView.setOnClickListener(footerClickListener);
if(footerHeight==-1 && mFooterView!=null){
mFooterView.show();
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
footerHeight = mFooterView.getMeasuredHeight();//这里的测量一般不会出问题
Log.i("Alex2", "底部高度为" + footerHeight);
}
updateFooterHeight(dy);
}else {
isBottom = false;
}
}
});
}
/**
* enable or disable pull up load more feature.
*
* @param enable
*/
public void setPullLoadEnable(boolean enable) {
mPullLoading = false;
mEnablePullLoad = enable;
if(adapter!=null)adapter.setPullLoadMoreEnable(enable);//adapter和recyclerView要同时设置
if(mFooterView==null)return;
if (!mEnablePullLoad) {
// this.smoothScrollBy(0,-footerHeight);
mFooterView.hide();
mFooterView.setOnClickListener(null);
mFooterView.setBottomMargin(0);
//make sure "pull up" don't show a line in bottom when listview with one page
} else {
mFooterView.show();
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
mFooterView.setVisibility(VISIBLE);
//make sure "pull up" don't show a line in bottom when listview with one page
// both "pull up" and "click" will invoke load more.
mFooterView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startLoadMore();
}
});
}
}
/**
* stop load more, reset footer view.
*/
public void stopLoadMore() {
if (mPullLoading == true) {
mPullLoading = false;
mFooterView.show();
mFooterView.setState(CustomDragFooterView.STATE_NORMAL);
}
}
private void startLoadMore() {
mPullLoading = true;
mFooterView.setState(CustomDragFooterView.STATE_LOADING);
Log.i("Alex2", "现在开始加载");
mIsFooterReady = false;
if (loadMoreListener != null) {
loadMoreListener.onLoadMore();
}
}
/**
* 在刷新时要执行的方法
*/
public interface LoadMoreListener{
public void onLoadMore();
}
/**
* 点击loadMore后要执行的事件
*/
class footerViewClickListener implements View.OnClickListener {
@Override
public void onClick(View v) {
startLoadMore();
}
}
public static class CustomDragRecyclerFooterView extends LinearLayout {
public final static int STATE_NORMAL = 0;
public final static int STATE_READY = 1;
public final static int STATE_LOADING = 2;
private Context mContext;
private View mContentView;
private View mProgressBar;
private TextView mHintView;
public CustomDragRecyclerFooterView(Context context) {
super(context);
initView(context);
}
public CustomDragRecyclerFooterView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
}
public void setState(int state) {
mHintView.setVisibility(View.INVISIBLE);
mProgressBar.setVisibility(View.INVISIBLE);
mHintView.setVisibility(View.INVISIBLE);
if (state == STATE_READY) {
mHintView.setVisibility(View.VISIBLE);
mHintView.setText(R.string.xlistview_footer_hint_ready);
} else if (state == STATE_LOADING) {
mProgressBar.setVisibility(View.VISIBLE);
} else {
mHintView.setVisibility(View.VISIBLE);
mHintView.setText(R.string.xlistview_footer_hint_normal);
}
}
public void setBottomMargin(int height) {
if (height < 0) return ;
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
lp.bottomMargin = height;
mContentView.setLayoutParams(lp);
}
public int getBottomMargin() {
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
return lp.bottomMargin;
}
/**
* normal status
*/
public void normal() {
mHintView.setVisibility(View.VISIBLE);
mProgressBar.setVisibility(View.GONE);
}
/**
* loading status
*/
public void loading() {
mHintView.setVisibility(View.GONE);
mProgressBar.setVisibility(View.VISIBLE);
}
/**
* hide footer when disable pull load more
*/
public void hide() {
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
lp.height = 1;//这里如果设为0那么layoutManger就会抓不到
mContentView.setLayoutParams(lp);
mContentView.setBackgroundColor(Color.BLACK);//这里的颜色要和自己的背景色一致
}
/**
* show footer
*/
public void show() {
LayoutParams lp = (LayoutParams)mContentView.getLayoutParams();
lp.height = LayoutParams.WRAP_CONTENT;
lp.width = LayoutParams.MATCH_PARENT;
mContentView.setLayoutParams(lp);
mContentView.setBackgroundColor(Color.WHITE);//这里的颜色要和自己的背景色一致
}
private void initView(Context context) {
mContext = context;
this.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
LinearLayout moreView = (LinearLayout) LayoutInflater.from(mContext).inflate(R.layout.layout_customdragfooterview, null);
addView(moreView);
moreView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
mContentView = moreView.findViewById(R.id.rlContentView);
mProgressBar = moreView.findViewById(R.id.pbContentView);
mHintView = (TextView)moreView.findViewById(R.id.ctvContentView);
}
}
public static abstract class AlxDragRecyclerViewAdapter<T> extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
private static final int TYPE_HEADER = 0;
private static final int TYPE_ITEM = 1;
private static final int TYPE_FOOTER = 2;
private int ITEM;
private int HEADER;
private ViewHolder vhHeader;
private ViewHolder vhItem;
boolean loadMore;
private List<T> dataList;
public List<T> getDataList() {
return dataList;
}
public void setDataList(List<T> dataList) {
this.dataList = dataList;
}
public AlxDragRecyclerViewAdapter(List<T> dataList,int headerLayout,int itemLayout,boolean pullEnable){
this.dataList = dataList;
this.ITEM = itemLayout;
this.HEADER = headerLayout;
this.loadMore = pullEnable;
}
public abstract ViewHolder setItemViewHolder(View itemView);
public abstract ViewHolder setHeaderViewHolder(View headerView);
private T getObject(int position){
if(HEADER!=0 && dataList!=null && dataList.size()>=position)return dataList.get(position-1);//如果有header
if(dataList!=null && dataList.size() >= (position+1))return dataList.get(position);//如果没有header
return null;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_ITEM) {
//inflate your layout and pass it to view holder
View itemView = LayoutInflater.from(parent.getContext()).inflate(ITEM,null);
Log.i("Alex","itemView是"+itemView);
this.vhItem = setItemViewHolder(itemView);
Log.i("Alex","vhItem是"+vhItem);
return vhItem;
} else if (viewType == TYPE_HEADER) {
//inflate your layout and pass it to view holder
View headerView = LayoutInflater.from(parent.getContext()).inflate(HEADER,null);
Log.i("Alex","headerView是"+headerView);
this.vhHeader = setHeaderViewHolder(headerView);
Log.i("Alex","vhItem是"+vhItem);
return this.vhHeader;
} else if(viewType==TYPE_FOOTER){
CustomDragRecyclerFooterView footerView = new CustomDragRecyclerFooterView(parent.getContext());
return new VHFooter(footerView);
}
throw new RuntimeException("there is no type that matches the type " + viewType + " + make sure your using types correctly");
}
public void setPullLoadMoreEnable(boolean enable){
this.loadMore = enable;
}
public boolean getPullLoadMoreEnable(){return loadMore;}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {//相当于getView
Log.i("Alex","正在绑定"+position+" "+holder.getClass());
if (vhItem!=null && holder.getClass() == vhItem.getClass()) {
//cast holder to VHItem and set data
initItemView(holder,position,getObject(position));
}else if (vhHeader!=null && holder.getClass() == vhHeader.getClass()) {
//cast holder to VHHeader and set data for header.
initHeaderView(holder);
}else if(holder instanceof AlxDragRecyclerViewAdapter.VHFooter){
if(!loadMore)((VHFooter)holder).footerView.hide();//第一次初始化显示的时候要不要显示footerView
}
}
@Override
public int getItemCount() {
if(HEADER==0)return dataList==null?0:dataList.size() + 1;//如果没有header
return dataList==null?1:dataList.size() + 2;//如果有header
}//这里要考虑到头尾部，多以要加2
/**
* 根据位置判断这里该用哪个ViewHolder
* @param position
* @return
*/
@Override
public int getItemViewType(int position) {
if (position == 0 && HEADER!=0)return TYPE_HEADER;
else if(isPositonFooter(position))return TYPE_FOOTER;
return TYPE_ITEM;
}
private boolean isPositonFooter(int position){//这里的position从0算起
if(HEADER!=0) {//如果有header
if (dataList == null && position == 1) return true;//如果没有item
return position == dataList.size() + 1;//如果有item(也许为0)
}
//如果没有header
if (dataList == null && position == 0) return true;//第一行就是footer
return position == dataList.size();
}
//自定义Viewholder的事例
// class VHItem extends RecyclerView.ViewHolder {
// public VHItem(View itemView) {
// super(itemView);
// }
// public View getItemView(){return itemView;}
// }
//
// class VHHeader extends RecyclerView.ViewHolder {
//
// public VHHeader(View headerView) {
// super(headerView);
//
// }
// }
class VHFooter extends RecyclerView.ViewHolder {
CustomDragRecyclerFooterView footerView;
public VHFooter(View itemView) {
super(itemView);
footerView = (CustomDragRecyclerFooterView)itemView;
}
}
public abstract void initItemView(ViewHolder itemHolder,int posion,T entity);
public abstract void initHeaderView(final ViewHolder headerHolder);
}
}