android listivew 下拉回弹刷新
来源：互联网 发布：优惠券采集网站源码 编辑：程序博客网 时间：2024/05/22 11:35
该效果是一名国外工程师（johannilsson）的代码，拿来研究了下，自己整合了一下，现在拿出来，跟大家一起分享。
再次感谢这位国外工程师（johannilsson），谢谢！
新浪微博，和QQ空间里面，都有那个下拉刷新的效果，另很多人眼前一亮，细细分析，原理原来如此。
在原作者的基础上，写了一些注释，和帮助大家更好的阅读理解，（可能其中有些地方注释不准，欢迎指正，谢谢）
下面，就亮出关键代码：
**** 自定义listivew （关键代码）
public class PullToRefreshListView extends ListView implements OnScrollListener { private static final int TAP_TO_REFRESH = 1; // 初始状态 private static final int PULL_TO_REFRESH = 2; //拉动刷新 private static final int RELEASE_TO_REFRESH = 3; //释放刷新 private static final int REFRESHING = 4; //正在刷新 private static final String TAG = "PullToRefreshListView"; //刷新接口 private OnRefreshListener mOnRefreshListener; //箭头图片 private static int REFRESHICON = R.drawable.goicon; /** * listview 滚动监听器 */ private OnScrollListener mOnScrollListener; //视图索引器 private LayoutInflater mInflater; /** * 头部视图 内容 -- start */ private RelativeLayout mRefreshView; private TextView mRefreshViewText; private ImageView mRefreshViewImage; private ProgressBar mRefreshViewProgress; private TextView mRefreshViewLastUpdated; /** * 头部视图 内容 -- end */ //当前listivew 的滚动状态 private int mCurrentScrollState; //当前listview 的刷新状态 private int mRefreshState; //动画效果 //变为向下的箭头 private RotateAnimation mFlipAnimation; //变为逆向的箭头 private RotateAnimation mReverseFlipAnimation; //头视图的高度 private int mRefreshViewHeight; //头视图 原始的top padding 属性值 private int mRefreshOriginalTopPadding; // private int mLastMotionY; //是否反弹 private boolean mBounceHack; public PullToRefreshListView(Context context) { super(context); init(context); } public PullToRefreshListView(Context context, AttributeSet attrs) { super(context, attrs); init(context); } public PullToRefreshListView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(context); } private void init(Context context) { // Load all of the animations we need in code rather than through XML //初始化动画 // mFlipAnimation = new RotateAnimation(0, -180, RotateAnimation.RELATIVE_TO_SELF, 0.5f, RotateAnimation.RELATIVE_TO_SELF, 0.5f); mFlipAnimation.setInterpolator(new LinearInterpolator()); mFlipAnimation.setDuration(250); mFlipAnimation.setFillAfter(true); mReverseFlipAnimation = new RotateAnimation(-180, 0, RotateAnimation.RELATIVE_TO_SELF, 0.5f, RotateAnimation.RELATIVE_TO_SELF, 0.5f); mReverseFlipAnimation.setInterpolator(new LinearInterpolator()); mReverseFlipAnimation.setDuration(250); mReverseFlipAnimation.setFillAfter(true); mInflater = (LayoutInflater) context.getSystemService( Context.LAYOUT_INFLATER_SERVICE); mRefreshView = (RelativeLayout) mInflater.inflate(R.layout.pull_to_refresh_header, this, false);//(R.layout.pull_to_refresh_header, null); mRefreshViewText = (TextView) mRefreshView.findViewById(R.id.pull_to_refresh_text); mRefreshViewImage = (ImageView) mRefreshView.findViewById(R.id.pull_to_refresh_image); mRefreshViewProgress = (ProgressBar) mRefreshView.findViewById(R.id.pull_to_refresh_progress); mRefreshViewLastUpdated = (TextView) mRefreshView.findViewById(R.id.pull_to_refresh_updated_at); mRefreshViewImage.setMinimumHeight(50); mRefreshView.setOnClickListener(new OnClickRefreshListener()); mRefreshOriginalTopPadding = mRefreshView.getPaddingTop(); mRefreshState = TAP_TO_REFRESH; addHeaderView(mRefreshView); super.setOnScrollListener(this); measureView(mRefreshView); mRefreshViewHeight = mRefreshView.getMeasuredHeight(); //获取头文件的测量高度 } @Override protected void onAttachedToWindow() { setSelection(1); } @Override public void setAdapter(ListAdapter adapter) { super.setAdapter(adapter); setSelection(1); } /** * Set the listener that will receive notifications every time the list * scrolls. * * @param l The scroll listener. */ @Override public void setOnScrollListener(AbsListView.OnScrollListener l) { mOnScrollListener = l; } /** * Register a callback to be invoked when this list should be refreshed. * * @param onRefreshListener The callback to run. */ public void setOnRefreshListener(OnRefreshListener onRefreshListener) { mOnRefreshListener = onRefreshListener; } /** * Set a text to represent when the list was last updated. * @param lastUpdated Last updated at. */ public void setLastUpdated(CharSequence lastUpdated) { if (lastUpdated != null) { mRefreshViewLastUpdated.setVisibility(View.VISIBLE); mRefreshViewLastUpdated.setText(lastUpdated); } else { mRefreshViewLastUpdated.setVisibility(View.GONE); } } @Override public boolean onTouchEvent(MotionEvent event) { //当前手指的Y值 final int y = (int) event.getY(); //Log.i(TAG, "触屏的Y值"+y); mBounceHack = false; //不反弹 switch (event.getAction()) { case MotionEvent.ACTION_UP: //将垂直滚动条设置为可用状态 if (!isVerticalScrollBarEnabled()) { setVerticalScrollBarEnabled(true); } //如果头部刷新条出现，并且不是正在刷新状态 if (getFirstVisiblePosition() == 0 && mRefreshState != REFRESHING) { if ((mRefreshView.getBottom() >= mRefreshViewHeight || mRefreshView.getTop() >= 0) && mRefreshState == RELEASE_TO_REFRESH) { //如果头部视图处于拉离顶部的情况 // Initiate the refresh mRefreshState = REFRESHING; //将标量设置为，正在刷新 prepareForRefresh(); //准备刷新 onRefresh(); //刷新 } else if (mRefreshView.getBottom() < mRefreshViewHeight || mRefreshView.getTop() <= 0) { // Abort refresh and scroll down below the refresh view // 停止刷新，并且滚动到头部刷新视图的下一个视图 resetHeader(); setSelection(1); //定位在第二个列表项 } } break; case MotionEvent.ACTION_DOWN: mLastMotionY = y; //跟踪手指的Y值 break; case MotionEvent.ACTION_MOVE: //更行头视图的toppadding 属性 applyHeaderPadding(event); break; } return super.onTouchEvent(event); } /**** * 不断的头部的top padding 属性 * @param ev */ private void applyHeaderPadding(MotionEvent ev) { //获取累积的动作数 int pointerCount = ev.getHistorySize(); // Log.i(TAG, "获取累积的动作数"+pointerCount); for (int p = 0; p < pointerCount; p++) { if (mRefreshState == RELEASE_TO_REFRESH) { //如果是释放将要刷新状态 if (isVerticalFadingEdgeEnabled()) { setVerticalScrollBarEnabled(false); } //历史累积的高度 int historicalY = (int) ev.getHistoricalY(p); //Log.i(TAG, "单个动作getHistoricalY值："+historicalY); // Calculate the padding to apply, we divide by 1.7 to // simulate a more resistant effect during pull. int topPadding = (int) (((historicalY - mLastMotionY) - mRefreshViewHeight) / 1.7); mRefreshView.setPadding( mRefreshView.getPaddingLeft(), topPadding, mRefreshView.getPaddingRight(), mRefreshView.getPaddingBottom()); } } } /** * Sets the header padding back to original size. * 使头部视图的toppadding 恢复到初始值 */ private void resetHeaderPadding() { mRefreshView.setPadding( mRefreshView.getPaddingLeft(), mRefreshOriginalTopPadding, mRefreshView.getPaddingRight(), mRefreshView.getPaddingBottom()); } /** * Resets the header to the original state. * 初始化头部视图 状态 */ private void resetHeader() { if (mRefreshState != TAP_TO_REFRESH) { mRefreshState = TAP_TO_REFRESH; //初始刷新状态 //使头部视图的toppadding 恢复到初始值 resetHeaderPadding(); // Set refresh view text to the pull label //将文字初始化 mRefreshViewText.setText(R.string.pull_to_refresh_tap_label); // Replace refresh drawable with arrow drawable //设置初始图片 mRefreshViewImage.setImageResource(REFRESHICON); // Clear the full rotation animation // 清除动画 mRefreshViewImage.clearAnimation(); // Hide progress bar and arrow. //隐藏头视图 mRefreshViewImage.setVisibility(View.GONE); //隐藏进度条 mRefreshViewProgress.setVisibility(View.GONE); } } //测量视图的高度 private void measureView(View child) { //获取头部视图属性 ViewGroup.LayoutParams p = child.getLayoutParams(); if (p == null) { p = new ViewGroup.LayoutParams( ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT); } int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0, p.width); int lpHeight = p.height; int childHeightSpec; //不懂MeasureSpec------------------------------------------------------------------------------------------ if (lpHeight > 0) { //如果视图的高度大于0 childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight, MeasureSpec.EXACTLY); } else { childHeightSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); } child.measure(childWidthSpec, childHeightSpec); //不懂MeasureSpec------------------------------------------------------------------------------------------ } /**** * 滑动事件 */ @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { // When the refresh view is completely visible, change the text to say // "Release to refresh..." and flip the arrow drawable. if (mCurrentScrollState == SCROLL_STATE_TOUCH_SCROLL //如果是接触滚动状态,并且不是正在刷新的状态 && mRefreshState != REFRESHING) { if (firstVisibleItem == 0) { //如果显示出来了第一个列表项 //显示刷新图片 mRefreshViewImage.setVisibility(View.VISIBLE); if ((mRefreshView.getBottom() >= mRefreshViewHeight + 20 || mRefreshView.getTop() >= 0) && mRefreshState != RELEASE_TO_REFRESH) { //如果下拉了listiview,则显示上拉刷新动画 mRefreshViewText.setText(R.string.pull_to_refresh_release_label); mRefreshViewImage.clearAnimation(); mRefreshViewImage.startAnimation(mFlipAnimation); mRefreshState = RELEASE_TO_REFRESH; Log.i(TAG, "现在处于下拉状态"); } else if (mRefreshView.getBottom() < mRefreshViewHeight + 20 && mRefreshState != PULL_TO_REFRESH) { //如果没有到达，下拉刷新距离，则回归原来的状态 mRefreshViewText.setText(R.string.pull_to_refresh_pull_label); if (mRefreshState != TAP_TO_REFRESH) { mRefreshViewImage.clearAnimation(); mRefreshViewImage.startAnimation(mReverseFlipAnimation); Log.i(TAG, "现在处于回弹状态"); } mRefreshState = PULL_TO_REFRESH; } } else { mRefreshViewImage.setVisibility(View.GONE); //隐藏刷新图片 resetHeader(); //初始化，头部 } } else if (mCurrentScrollState == SCROLL_STATE_FLING //如果是自己滚动状态+ 第一个视图已经显示+ 不是刷新状态 && firstVisibleItem == 0 && mRefreshState != REFRESHING) { setSelection(1); mBounceHack = true; //状态为回弹 Log.i(TAG, "现在处于自由滚动到顶部的状态"); } else if (mBounceHack && mCurrentScrollState == SCROLL_STATE_FLING) { setSelection(1); Log.i(TAG, "现在处于自由滚动到顶部的状态"); } if (mOnScrollListener != null) { mOnScrollListener.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount); } } //滚动状态改变 @Override public void onScrollStateChanged(AbsListView view, int scrollState) { mCurrentScrollState = scrollState; if (mCurrentScrollState == SCROLL_STATE_IDLE) { //如果滚动停顿 mBounceHack = false; } if (mOnScrollListener != null) { mOnScrollListener.onScrollStateChanged(view, scrollState); } } //准备刷新 public void prepareForRefresh() { resetHeaderPadding(); //初始化，头部文件 mRefreshViewImage.setVisibility(View.GONE); // We need this hack, otherwise it will keep the previous drawable. mRefreshViewImage.setImageDrawable(null); mRefreshViewProgress.setVisibility(View.VISIBLE); // Set refresh view text to the refreshing label mRefreshViewText.setText(R.string.pull_to_refresh_refreshing_label); mRefreshState = REFRESHING; } //刷新 public void onRefresh() { Log.d(TAG, "执行刷新"); if (mOnRefreshListener != null) { mOnRefreshListener.onRefresh(); } } /** * 刷新完成 的回调函数 * Resets the list to a normal state after a refresh. * @param lastUpdated Last updated at. */ public void onRefreshComplete(CharSequence lastUpdated) { setLastUpdated(lastUpdated); onRefreshComplete(); } /** * 刷新完成回调函数 * Resets the list to a normal state after a refresh. */ public void onRefreshComplete() { Log.d(TAG, "onRefreshComplete"); resetHeader(); // If refresh view is visible when loading completes, scroll down to // the next item. if (mRefreshView.getBottom() > 0) { invalidateViews(); //重绘视图 setSelection(1); } } /** * Invoked when the refresh view is clicked on. This is mainly used when * there's only a few items in the list and it's not possible to drag the * list. */ private class OnClickRefreshListener implements OnClickListener { @Override public void onClick(View v) { if (mRefreshState != REFRESHING) { //准备刷新 prepareForRefresh(); //刷新 onRefresh(); } } } /** * 刷新方法接口 */ public interface OnRefreshListener { public void onRefresh(); }
---------
------
* 如果你还是没有弄明白的话，那就点击下面的链接，来下载整个demo项目:
http://download.csdn.net/detail/zjl5211314/3775209
原作者：johannilsson
选自：https://github.com/johannilsson/android-pulltorefresh
- android listivew 下拉回弹刷新
- android listivew 下拉回弹刷新
- android listivew 下拉回弹刷新
- android listivew 下拉回弹刷新
- android之listivew实现下拉刷新
- android之listivew实现下拉刷新
- Android基础--listivew实现下拉刷新
- ListView下拉回弹刷新
- ListView下拉回弹刷新
- ListView下拉回弹刷新
- Android仿QQ下拉刷新、上拉回弹
- Android ScrollLayout 下拉回弹
- android 下拉回弹的效果
- 我的Android进阶之旅------>Android之ListView实现下拉回弹刷新
- 使用react-native-pull实现跨平台Android&IOS下拉刷新滑动回弹效果
- listivew单条刷新
- android 仿qq5.3，下拉刷新，自动加载更多，下拉回弹，仿IOS橡皮筋效果，通用版，效果完美
- android 仿qq5.3，下拉刷新，自动加载更多，下拉回弹，仿IOS橡皮筋效果，通用版，效果完美
- 通往java高手之路
- 系统库按时间生成IO TOP SQL语句(08点-11点)
- mysql反向解析导致连接慢的问题
- memset()的效率以及源码分析
- centos CR repo
- android listivew 下拉回弹刷新
- UNIX环境中Real time, User time and Sys time
- (l转)HDFS小文件问题及解决方法
- Android系统平台progurad混淆功能使能
- hive的编译模块设计
- 5.7学习心得
- Struts2截取字符串的方法
- ASP.NET页面间数据传递的方法
- 获取sql server时间
