android ListView实现下拉上拉刷新功能

主ListView类：

package com.carcare.refresh;/*** @file XListView.java* @package me.maxwin.view* @create Mar 18, 2012 6:28:41 PM* @author Maxwin* @description An ListView support (a) Pull down to refresh, (b) Pull up to load more.* 		Implement IXListViewListener, and see stopRefresh() / stopLoadMore().*/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.BaseAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
import android.widget.TextView;import com.carcare.updataversion.cjh.R;public class NListView extends ListView implements OnScrollListener {private float mLastY = -1; // save event yprivate Scroller mScroller; // used for scroll backprivate OnScrollListener mScrollListener; // user's scroll listener// the interface to trigger refresh and load more.private IXListViewListener mListViewListener;// -- header viewprivate NListViewHeader 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 heightprivate boolean mEnablePullRefresh = true;private boolean mPullRefreshing = false; // is refreashing.// -- footer viewprivate NListViewFooter mFooterView;private RelativeLayout mFooterViewContent;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 durationprivate 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 NListView(Context context) {super(context);initWithContext(context);}public NListView(Context context, AttributeSet attrs) {super(context, attrs);initWithContext(context);}public NListView(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 viewmHeaderView = new NListViewHeader(context);mHeaderViewContent = (RelativeLayout) mHeaderView.findViewById(R.id.xlistview_header_content);mHeaderTimeView = (TextView) mHeaderView.findViewById(R.id.xlistview_header_time);addHeaderView(mHeaderView);// init footer viewmFooterView = new NListViewFooter(context);mFooterViewContent = (RelativeLayout) mFooterView.findViewById(R.id.xlistview_footer_content);// init header heightmHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {@Overridepublic void onGlobalLayout() {mHeaderViewHeight = mHeaderViewContent.getHeight();getViewTreeObserver().removeGlobalOnLayoutListener(this);}});}@Overridepublic 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 contentmHeaderViewContent.setVisibility(View.INVISIBLE);} else {mFooterViewContent.setVisibility(View.VISIBLE);}}/*** enable or disable pull up load more feature.* * @param enable*/public void setPullLoadEnable(boolean enable) {mEnablePullLoad = enable;if (!mEnablePullLoad) {mFooterViewContent.setVisibility(View.INVISIBLE);mFooterView.setOnClickListener(null);} else {mPullLoading = false;mFooterViewContent.setVisibility(View.VISIBLE);mFooterView.setState(NListViewFooter.STATE_NORMAL);// both "pull up" and "click" will invoke load more.mFooterView.setOnClickListener(new OnClickListener() {@Overridepublic 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(NListViewFooter.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(NListViewHeader.STATE_READY);} else {mHeaderView.setState(NListViewHeader.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 computeScrollinvalidate();}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(NListViewFooter.STATE_READY);} else {mFooterView.setState(NListViewFooter.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(NListViewFooter.STATE_LOADING);if (mListViewListener != null) {mListViewListener.onLoadMore();}}@Overridepublic 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; // resetif (getFirstVisiblePosition() == 0) {// invoke refreshif (mEnablePullRefresh&& mHeaderView.getVisiableHeight() > mHeaderViewHeight) {mPullRefreshing = true;mHeaderView.setState(NListViewHeader.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);}@Overridepublic void computeScroll() {if (mScroller.computeScrollOffset()) {if (mScrollBack == SCROLLBACK_HEADER) {mHeaderView.setVisiableHeight(mScroller.getCurrY());} else {mFooterView.setBottomMargin(mScroller.getCurrY());}postInvalidate();invokeOnScrolling();}super.computeScroll();}@Overridepublic void setOnScrollListener(OnScrollListener l) {mScrollListener = l;}@Overridepublic void onScrollStateChanged(AbsListView view, int scrollState) {if (mScrollListener != null) {mScrollListener.onScrollStateChanged(view, scrollState);}}@Overridepublic void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount) {// send to user's listenermTotalItemCount = 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();}
}

ListView的FootView：

package com.carcare.refresh;
/*** @file XFooterView.java* @create Mar 31, 2012 9:33:43 PM* @author Maxwin* @description XListView's footer*/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.carcare.updataversion.cjh.R;public class NListViewFooter extends LinearLayout {public final static int STATE_NORMAL = 0;public final static int STATE_READY = 1;public final static int STATE_LOADING = 2;public final static int STATE_END = 3;private Context mContext;private View mContentView;private View mProgressBar;private TextView mHintView;public NListViewFooter(Context context) {super(context);initView(context);}public NListViewFooter(Context context, AttributeSet attrs) {super(context, attrs);initView(context);}public void setState(int state) {mHintView.setVisibility(View.GONE);mProgressBar.setVisibility(View.GONE);mHintView.setVisibility(View.GONE);if (state == STATE_READY) {mHintView.setVisibility(View.VISIBLE);mHintView.setText("松开刷新数据");} else if (state == STATE_LOADING) {mProgressBar.setVisibility(View.VISIBLE);} else if(state == STATE_NORMAL){mHintView.setVisibility(View.VISIBLE);mHintView.setText("查看更多消息");}else{mHintView.setVisibility(View.GONE);mProgressBar.setVisibility(View.GONE);mHintView.setVisibility(View.GONE);}}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);}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.FILL_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);}}

 ListView的HeaderView:

package com.carcare.refresh;/*** @file XListViewHeader.java* @create Apr 18, 2012 5:22:27 PM* @author Maxwin* @description XListView's header*/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.carcare.updataversion.cjh.R;public class NListViewHeader 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 NListViewHeader(Context context) {super(context);initView(context);}/*** @param context* @param attrs*/public NListViewHeader(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.FILL_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);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("下拉刷新");break;case STATE_READY:if (mState != STATE_READY) {mArrowImageView.clearAnimation();mArrowImageView.startAnimation(mRotateUpAnim);mHintTextView.setText("松开刷新");}break;case STATE_REFRESHING:mHintTextView.setText("正在刷新");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();}}

 XML布局：

xlistview_footer.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="fill_parent"android:layout_height="wrap_content" ><RelativeLayoutandroid:id="@+id/xlistview_footer_content"android:layout_width="fill_parent"android:layout_height="wrap_content"android:padding="10dp" ><ProgressBarandroid:id="@+id/xlistview_footer_progressbar"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"android:visibility="invisible"android:indeterminateDrawable="@drawable/progress_medium_white" /><TextViewandroid:id="@+id/xlistview_footer_hint_textview"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"android:text="查看更多消息" android:textColor="#000000"/></RelativeLayout></LinearLayout>

 xlistview_header.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="fill_parent"android:layout_height="wrap_content"android:gravity="bottom" ><RelativeLayoutandroid:id="@+id/xlistview_header_content"android:layout_width="fill_parent"android:layout_height="60dp" ><LinearLayoutandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"android:gravity="center"android:orientation="vertical" android:id="@+id/xlistview_header_text"><TextViewandroid:id="@+id/xlistview_header_hint_textview"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="下拉刷新" android:textColor="#000000"/><LinearLayoutandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_marginTop="3dp" ><TextViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:textSize="12sp" android:textColor="#000000"/><TextViewandroid:id="@+id/xlistview_header_time"android:layout_width="wrap_content"android:layout_height="wrap_content"android:textSize="12sp"android:textColor="#000000" /></LinearLayout></LinearLayout><ImageViewandroid:id="@+id/xlistview_header_arrow"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_alignLeft="@id/xlistview_header_text"android:layout_centerVertical="true"android:layout_marginLeft="-35dp"android:src="@drawable/news_z_arrow_down" /><ProgressBarandroid:id="@+id/xlistview_header_progressbar"android:layout_width="30dp"android:layout_height="30dp"android:layout_alignLeft="@id/xlistview_header_text"android:layout_centerVertical="true"android:layout_marginLeft="-40dp"android:visibility="invisible" android:indeterminateDrawable="@drawable/progress_medium_white"/></RelativeLayout></LinearLayout>