关于ListView的下拉刷新和上拉加载功能

需要这三个工具类

package com.example.Xlistview.ui;






import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewTreeObserver.OnGlobalLayoutListener;
import android.view.animation.DecelerateInterpolator;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
import android.widget.TextView;


import com.example.Xlistview.R;


public class XListView extends ListView implements OnScrollListener {


private float mLastY = -1; // save event y
private Scroller mScroller; // used for scroll back
private OnScrollListener mScrollListener; // user's scroll listener

// the interface to trigger refresh and load more.
private IXListViewListener mListViewListener;


// -- header view
private XListViewHeader mHeaderView;
// header view content, use it to calculate the Header's height. And hide it
// when disable pull refresh.
private RelativeLayout mHeaderViewContent;
private TextView mHeaderTimeView;
private int mHeaderViewHeight; // header view's height
private boolean mEnablePullRefresh = true;
private boolean mPullRefreshing = false; // is refreashing.


// -- footer view
private XListViewFooter mFooterView;
private boolean mEnablePullLoad;
private boolean mPullLoading;
private boolean mIsFooterReady = false;

// total list items, used to detect is at the bottom of listview.
private int mTotalItemCount;


// for mScroller, scroll back from header or footer.
private int mScrollBack;
private final static int SCROLLBACK_HEADER = 0;
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.


/**
* @param context
*/
public XListView(Context context) {
super(context);
initWithContext(context);
}


public XListView(Context context, AttributeSet attrs) {
super(context, attrs);
initWithContext(context);
}


public XListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initWithContext(context);
}


private void initWithContext(Context context) {
mScroller = new Scroller(context, new DecelerateInterpolator());
// XListView need the scroll event, and it will dispatch the event to
// user's listener (as a proxy).
super.setOnScrollListener(this);


// init header view
mHeaderView = new XListViewHeader(context);
mHeaderViewContent = (RelativeLayout) mHeaderView .findViewById(R.id.xlistview_header_content);
mHeaderTimeView = (TextView) mHeaderView .findViewById(R.id.xlistview_header_time);
addHeaderView(mHeaderView);


// init footer view
mFooterView = new XListViewFooter(context);


// init header height
mHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(
new OnGlobalLayoutListener() {
@SuppressWarnings("deprecation")
@Override
public void onGlobalLayout() {
mHeaderViewHeight = mHeaderViewContent.getHeight();
getViewTreeObserver()
.removeGlobalOnLayoutListener(this);
}
});
}


@Override
public void setAdapter(ListAdapter adapter) {
// make sure XListViewFooter is the last footer view, and only add once.
if (mIsFooterReady == false) {
mIsFooterReady = true;
addFooterView(mFooterView);
}
super.setAdapter(adapter);
}


/**
* enable or disable pull down refresh feature.
* 
* @param enable
*/
public void setPullRefreshEnable(boolean enable) {
mEnablePullRefresh = enable;
if (!mEnablePullRefresh) { // disable, hide the content
mHeaderViewContent.setVisibility(View.INVISIBLE);
} else {
mHeaderViewContent.setVisibility(View.VISIBLE);
}
}


/**
* enable or disable pull up load more feature.
* 
* @param enable
*/
public void setPullLoadEnable(boolean enable) {
mEnablePullLoad = enable;
if (!mEnablePullLoad) {
mFooterView.hide();
mFooterView.setOnClickListener(null);
} else {
mPullLoading = false;
mFooterView.show();
mFooterView.setState(XListViewFooter.STATE_NORMAL);
// both "pull up" and "click" will invoke load more.
mFooterView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startLoadMore();
}
});
}
}


/**
* stop refresh, reset header view.
*/
public void stopRefresh() {
if (mPullRefreshing == true) {
mPullRefreshing = false;
resetHeaderHeight();
}
}


/**
* stop load more, reset footer view.
*/
public void stopLoadMore() {
if (mPullLoading == true) {
mPullLoading = false;
mFooterView.setState(XListViewFooter.STATE_NORMAL);
}
}


/**
* set last refresh time
* 
* @param time
*/
public void setRefreshTime(String time) {
mHeaderTimeView.setText(time);
}


private void invokeOnScrolling() {
if (mScrollListener instanceof OnXScrollListener) {
OnXScrollListener l = (OnXScrollListener) mScrollListener;
l.onXScrolling(this);
}
}


private void updateHeaderHeight(float delta) {
mHeaderView.setVisiableHeight((int) delta
+ mHeaderView.getVisiableHeight());
if (mEnablePullRefresh && !mPullRefreshing) { // 未处于刷新状态，更新箭头
if (mHeaderView.getVisiableHeight() > mHeaderViewHeight) {
mHeaderView.setState(XListViewHeader.STATE_READY);
} else {
mHeaderView.setState(XListViewHeader.STATE_NORMAL);
}
}
setSelection(0); // scroll to top each time
}


/**
* reset header view's height.
*/
private void resetHeaderHeight() {
int height = mHeaderView.getVisiableHeight();
if (height == 0) // not visible.
return;
// refreshing and header isn't shown fully. do nothing.
if (mPullRefreshing && height <= mHeaderViewHeight) {
return;
}
int finalHeight = 0; // default: scroll back to dismiss header.
// is refreshing, just scroll back to show all the header.
if (mPullRefreshing && height > mHeaderViewHeight) {
finalHeight = mHeaderViewHeight;
}
mScrollBack = SCROLLBACK_HEADER;
mScroller.startScroll(0, height, 0, finalHeight - height,
SCROLL_DURATION);
// trigger computeScroll
invalidate();
}


private void updateFooterHeight(float delta) {
int height = mFooterView.getBottomMargin() + (int) delta;
if (mEnablePullLoad && !mPullLoading) {
if (height > PULL_LOAD_MORE_DELTA) { // height enough to invoke load
// more.
mFooterView.setState(XListViewFooter.STATE_READY);
} else {
mFooterView.setState(XListViewFooter.STATE_NORMAL);
}
}
mFooterView.setBottomMargin(height);


// setSelection(mTotalItemCount - 1); // scroll to bottom
}


private void resetFooterHeight() {
int bottomMargin = mFooterView.getBottomMargin();
if (bottomMargin > 0) {
mScrollBack = SCROLLBACK_FOOTER;
mScroller.startScroll(0, bottomMargin, 0, -bottomMargin,
SCROLL_DURATION);
invalidate();
}
}


private void startLoadMore() {
mPullLoading = true;
mFooterView.setState(XListViewFooter.STATE_LOADING);
if (mListViewListener != null) {
mListViewListener.onLoadMore();
}
}


@Override
public boolean onTouchEvent(MotionEvent ev) {
if (mLastY == -1) {
mLastY = ev.getRawY();
}


switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
mLastY = ev.getRawY();
break;
case MotionEvent.ACTION_MOVE:
final float deltaY = ev.getRawY() - mLastY;
mLastY = ev.getRawY();
if (getFirstVisiblePosition() == 0
&& (mHeaderView.getVisiableHeight() > 0 || deltaY > 0)) {
// the first item is showing, header has shown or pull down.
updateHeaderHeight(deltaY / OFFSET_RADIO);
invokeOnScrolling();
} else if (getLastVisiblePosition() == mTotalItemCount - 1
&& (mFooterView.getBottomMargin() > 0 || deltaY < 0)) {
// last item, already pulled up or want to pull up.
updateFooterHeight(-deltaY / OFFSET_RADIO);
}
break;
default:
mLastY = -1; // reset
if (getFirstVisiblePosition() == 0) {
// invoke refresh
if (mEnablePullRefresh && mHeaderView.getVisiableHeight() > mHeaderViewHeight) {
mPullRefreshing = true;
mHeaderView.setState(XListViewHeader.STATE_REFRESHING);
if (mListViewListener != null) {
mListViewListener.onRefresh();
}
}
resetHeaderHeight();
} else if (getLastVisiblePosition() == mTotalItemCount - 1) {
// invoke load more.
if (mEnablePullLoad && mFooterView.getBottomMargin() > PULL_LOAD_MORE_DELTA) {
startLoadMore();
}
resetFooterHeight();
}
break;
}
return super.onTouchEvent(ev);
}


@Override
public void computeScroll() {
if (mScroller.computeScrollOffset()) {
if (mScrollBack == SCROLLBACK_HEADER) {
mHeaderView.setVisiableHeight(mScroller.getCurrY());
} else {
mFooterView.setBottomMargin(mScroller.getCurrY());
}
postInvalidate();
invokeOnScrolling();
}
super.computeScroll();
}


@Override
public void setOnScrollListener(OnScrollListener l) {
mScrollListener = l;
}


@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
if (mScrollListener != null) {
mScrollListener.onScrollStateChanged(view, scrollState);
}
}


@Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
// send to user's listener
mTotalItemCount = totalItemCount;
if (mScrollListener != null) {
mScrollListener.onScroll(view, firstVisibleItem, visibleItemCount,
totalItemCount);
}
}


public void setXListViewListener(IXListViewListener l) {
mListViewListener = l;
}


/**
* you can listen ListView.OnScrollListener or this one. it will invoke
* onXScrolling when header/footer scroll back.
*/
public interface OnXScrollListener extends OnScrollListener {
public void onXScrolling(View view);
}


/**
* implements this interface to get refresh/load more event.
*/
public interface IXListViewListener {
public void onRefresh();


public void onLoadMore();
}

public void setFooterBackgroundRes(int resId) {
if (mFooterView != null) {
mFooterView.setBackgroundResource(resId);
}
}
public void setFooterBackgroundColor(int resId) {
if (mFooterView != null) {
mFooterView.setBackgroundColor(resId);
mFooterView.invalidate();
}
}
// public void showRefresh() {
// mPullRefreshing = true;
// mHeaderView.setVisiableHeight(mHeaderViewHeight);
// mHeaderView.setState(XListViewHeader.STATE_REFRESHING);
// mListViewListener.onRefresh();
// }
}

第二个:

package com.example.Xlistview.ui;


import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;


import com.example.Xlistview.R;


public class XListViewFooter 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 XListViewFooter(Context context) {
super(context);
initView(context);
}

public XListViewFooter(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 ;
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
lp.bottomMargin = height;
mContentView.setLayoutParams(lp);
}

public int getBottomMargin() {
LinearLayout.LayoutParams lp = (LinearLayout.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() {
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
lp.height = 0;
mContentView.setLayoutParams(lp);
}

/**
* show footer
*/
public void show() {
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
lp.height = LayoutParams.WRAP_CONTENT;
mContentView.setLayoutParams(lp);
}

private void initView(Context context) {
mContext = context;
LinearLayout moreView = (LinearLayout)LayoutInflater.from(mContext).inflate(R.layout.xlistview_footer, null);
addView(moreView);
moreView.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));

mContentView = moreView.findViewById(R.id.xlistview_footer_content);
mProgressBar = moreView.findViewById(R.id.xlistview_footer_progressbar);
mHintView = (TextView)moreView.findViewById(R.id.xlistview_footer_hint_textview);
}


}

第三个:

package com.example.Xlistview.ui;


import android.content.Context;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;


import com.example.Xlistview.R;


public class XListViewHeader extends LinearLayout {
private LinearLayout mContainer;
private ImageView mArrowImageView;
private ProgressBar mProgressBar;
private TextView mHintTextView;
private int mState = STATE_NORMAL;


private Animation mRotateUpAnim;
private Animation mRotateDownAnim;

private final int ROTATE_ANIM_DURATION = 180;

public final static int STATE_NORMAL = 0;
public final static int STATE_READY = 1;
public final static int STATE_REFRESHING = 2;


public XListViewHeader(Context context) {
super(context);
initView(context);
}


/**
* @param context
* @param attrs
*/
public XListViewHeader(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
}


private void initView(Context context) {
// 初始情况，设置下拉刷新view高度�?
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LayoutParams.MATCH_PARENT, 0);
mContainer = (LinearLayout) LayoutInflater.from(context).inflate(
R.layout.xlistview_header, null);
addView(mContainer, lp);
setGravity(Gravity.BOTTOM);


mArrowImageView = (ImageView)findViewById(R.id.xlistview_header_arrow);
mHintTextView = (TextView)findViewById(R.id.xlistview_header_hint_textview);
mProgressBar = (ProgressBar)findViewById(R.id.xlistview_header_progressbar);

mRotateUpAnim = new RotateAnimation(0.0f, -180.0f,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
if (isInEditMode()) {
return; 
}
mRotateUpAnim.setDuration(ROTATE_ANIM_DURATION);
mRotateUpAnim.setFillAfter(true);
mRotateDownAnim = new RotateAnimation(-180.0f, 0.0f,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
mRotateDownAnim.setDuration(ROTATE_ANIM_DURATION);
mRotateDownAnim.setFillAfter(true);
}


public void setState(int state) {
if (state == mState) return ;

if (state == STATE_REFRESHING) {// 显示进度
mArrowImageView.clearAnimation();
mArrowImageView.setVisibility(View.INVISIBLE);
mProgressBar.setVisibility(View.VISIBLE);
} else { // 显示箭头图片
mArrowImageView.setVisibility(View.VISIBLE);
mProgressBar.setVisibility(View.INVISIBLE);
}

switch(state){
case STATE_NORMAL:
if (mState == STATE_READY) {
mArrowImageView.startAnimation(mRotateDownAnim);
}
if (mState == STATE_REFRESHING) {
mArrowImageView.clearAnimation();
}
mHintTextView.setText(R.string.xlistview_header_hint_normal);
break;
case STATE_READY:
if (mState != STATE_READY) {
mArrowImageView.clearAnimation();
mArrowImageView.startAnimation(mRotateUpAnim);
mHintTextView.setText(R.string.xlistview_header_hint_ready);
}
break;
case STATE_REFRESHING:
mHintTextView.setText(R.string.xlistview_header_hint_loading);
break;
default:
}

mState = state;
}

public void setVisiableHeight(int height) {
if (height < 0)
height = 0;
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) mContainer
.getLayoutParams();
lp.height = height;
mContainer.setLayoutParams(lp);
}


public int getVisiableHeight() {
return mContainer.getHeight();
}


}

MainActivity：

package com.example.Xlistview;


import java.text.ParseException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.List;
import java.util.Random;


import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.widget.ArrayAdapter;


import com.example.Xlistview.ui.XListView;
import com.example.Xlistview.ui.XListView.IXListViewListener;


public class MainActivity extends Activity implements IXListViewListener {
XListView list = null;
private Handler handler = new Handler();


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
list = (XListView) findViewById(R.id.listview);
list.setXListViewListener(this);
list.setPullLoadEnable(true);// 开启加载更多
list.setPullRefreshEnable(true);// 开启下拉刷新
list.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_expandable_list_item_1, getData()));
}


private List<String> getData() {
List<String> data = new ArrayList<String>();
data.add("测试数据1");
data.add("测试数据2");
data.add("测试数据3");
data.add("测试数据4");
return data;
}


@Override
public void onRefresh() {
// TODO Auto-generated method stub
Log.i("syso", "下拉刷新的时候会触发该方法");
handler.postDelayed(new Runnable() {


@Override
public void run() {
list.setRefreshTime("今天");
list.stopRefresh();// 让下拉刷新的圈圈消失
}
}, 3000);
}


@Override
public void onLoadMore() {
// TODO Auto-generated method stub
Log.i("syso", "上拉加载更多时触发,历史数据");


handler.postDelayed(new Runnable() {


@Override
public void run() {
list.setRefreshTime("今天");
list.stopLoadMore();// 让下拉刷新的圈圈消失
}
}, 3000);
}


}

注意:实现接口，并设置参数。覆盖的方法中最好用handler来模拟耗时任务，不要用sleep