Android仿百度外卖自定义下拉刷新效果

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical"android:layout_width="match_parent"android:layout_height="wrap_content"><ImageViewandroid:id="@+id/iv_back1"android:src="@drawable/pull_back"android:layout_width="match_parent"android:layout_height="100dp" /><ImageViewandroid:id="@+id/iv_back2"android:src="@drawable/pull_back"android:layout_width="match_parent"android:layout_height="100dp" /><RelativeLayoutandroid:id="@+id/main"android:layout_centerHorizontal="true"android:layout_width="wrap_content"android:layout_height="wrap_content"><ImageViewandroid:layout_marginTop="45dp"android:id="@+id/iv_rider"android:background="@drawable/pull_rider"android:layout_width="50dp"android:layout_height="50dp" /><ImageViewandroid:id="@+id/wheel1"android:layout_marginLeft="10dp"android:layout_marginTop="90dp"android:background="@drawable/pull_wheel"android:layout_width="15dp"android:layout_height="15dp" /><ImageViewandroid:id="@+id/wheel2"android:layout_marginLeft="40dp"android:layout_marginTop="90dp"android:background="@drawable/pull_wheel"android:layout_width="15dp"android:layout_height="15dp" /></RelativeLayout><ImageViewandroid:id="@+id/ivsun"android:layout_marginTop="20dp"android:layout_toRightOf="@+id/main"android:background="@drawable/pull_sun"android:layout_width="30dp"android:layout_height="30dp" /></RelativeLayout>

<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android" android:interpolator="@android:anim/accelerate_interpolator"><translate android:fromXDelta="100%p" android:toXDelta="0%p"android:repeatMode="restart"android:interpolator="@android:anim/linear_interpolator"android:repeatCount="infinite"android:duration="5000" /></set>

<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android" android:interpolator="@android:anim/accelerate_interpolator"><translate android:fromXDelta="0%p" android:toXDelta="-100%p"android:repeatMode="restart"android:interpolator="@android:anim/linear_interpolator"android:repeatCount="infinite"android:duration="5000" /></set>

<?xml version="1.0" encoding="utf-8"?><set xmlns:android="http://schemas.android.com/apk/res/android"><rotateandroid:fromDegrees="0"android:toDegrees="360"android:duration="1000"android:repeatCount="-1"android:pivotX="50%"android:pivotY="50%" /></set>

package com.hankkin.baidugoingrefreshlayout;import android.widget.AbsListView;import android.widget.ListView;import android.content.Context;import android.util.AttributeSet;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.ViewGroup;import android.view.animation.Animation;import android.view.animation.AnimationUtils;import android.widget.ImageView;import android.widget.RelativeLayout;/*** Created by Hankkin on 16/4/10.*/public class BaiDuRefreshListView extends ListView implements AbsListView.OnScrollListener{private static final int DONE = 0; //刷新完毕状态private static final int PULL_TO_REFRESH = 1; //下拉刷新状态private static final int RELEASE_TO_REFRESH = 2; //释放状态private static final int REFRESHING = 3; //正在刷新状态private static final int RATIO = 3;private RelativeLayout headView; //下拉刷新头private int headViewHeight; //头高度private float startY; //开始Y坐标private float offsetY; //Y轴偏移量private OnBaiduRefreshListener mOnRefreshListener; //刷新接口private int state; //状态值private int mFirstVisibleItem; //第一项可见item索引private boolean isRecord; //是否记录private boolean isEnd; //是否结束private boolean isRefreable; //是否刷新private ImageView ivWheel1,ivWheel2; //轮组图片组件private ImageView ivRider; //骑手图片组件private ImageView ivSun,ivBack1,ivBack2; //太阳、背景图片1、背景图片2private Animation wheelAnimation,sunAnimation; //轮子、太阳动画private Animation backAnimation1,backAnimation2; //两张背景图动画public BaiDuRefreshListView(Context context) {super(context);init(context);}public BaiDuRefreshListView(Context context, AttributeSet attrs) {super(context, attrs);init(context);}public BaiDuRefreshListView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);init(context);}public interface OnBaiduRefreshListener{void onRefresh();}/*** 回调接口，想实现下拉刷新的listview实现此接口* @param onRefreshListener*/public void setOnBaiduRefreshListener(OnBaiduRefreshListener onRefreshListener){mOnRefreshListener = onRefreshListener;isRefreable = true;}/*** 刷新完毕，从主线程发送过来，并且改变headerView的状态和文字动画信息*/public void setOnRefreshComplete(){//一定要将isEnd设置为true，以便于下次的下拉刷新isEnd = true;state = DONE;changeHeaderByState(state);}private void init(Context context) {//关闭view的OverScrollsetOverScrollMode(OVER_SCROLL_NEVER);setOnScrollListener(this);//加载头布局headView = (RelativeLayout) LayoutInflater.from(context).inflate(R.layout.headview,this,false);//测量头布局measureView(headView);//给ListView添加头布局addHeaderView(headView);//设置头文件隐藏在ListView的第一项headViewHeight = headView.getMeasuredHeight();headView.setPadding(0, -headViewHeight, 0, 0);//获取头布局图片组件ivRider = (ImageView) headView.findViewById(R.id.iv_rider);ivSun = (ImageView) headView.findViewById(R.id.ivsun);ivWheel1 = (ImageView) headView.findViewById(R.id.wheel1);ivWheel2 = (ImageView) headView.findViewById(R.id.wheel2);ivBack1 = (ImageView) headView.findViewById(R.id.iv_back1);ivBack2 = (ImageView) headView.findViewById(R.id.iv_back2);//获取动画wheelAnimation = AnimationUtils.loadAnimation(context, R.anim.tip);sunAnimation = AnimationUtils.loadAnimation(context, R.anim.tip1);backAnimation1 = AnimationUtils.loadAnimation(context, R.anim.a);backAnimation2 = AnimationUtils.loadAnimation(context, R.anim.b);state = DONE;isEnd = true;isRefreable = false;}@Overridepublic void onScrollStateChanged(AbsListView absListView, int i) {}@Overridepublic void onScroll(AbsListView absListView, int firstVisibleItem, int visibleItemCount, int totalItemCount) {mFirstVisibleItem = firstVisibleItem;}@Overridepublic boolean onTouchEvent(MotionEvent ev) {if (isEnd) {//如果现在时结束的状态，即刷新完毕了，可以再次刷新了，在onRefreshComplete中设置if (isRefreable) {//如果现在是可刷新状态 在setOnMeiTuanListener中设置为trueswitch (ev.getAction()){//用户按下case MotionEvent.ACTION_DOWN://如果当前是在listview顶部并且没有记录y坐标if (mFirstVisibleItem == 0 && !isRecord) {//将isRecord置为true，说明现在已记录y坐标isRecord = true;//将当前y坐标赋值给startY起始y坐标startY = ev.getY();}break;//用户滑动case MotionEvent.ACTION_MOVE://再次得到y坐标，用来和startY相减来计算offsetY位移值float tempY = ev.getY();//再起判断一下是否为listview顶部并且没有记录y坐标if (mFirstVisibleItem == 0 && !isRecord) {isRecord = true;startY = tempY;}//如果当前状态不是正在刷新的状态，并且已经记录了y坐标if (state!=REFRESHING && isRecord ) {//计算y的偏移量offsetY = tempY - startY;//计算当前滑动的高度float currentHeight = (-headViewHeight+offsetY/3);//用当前滑动的高度和头部headerView的总高度进行比 计算出当前滑动的百分比 0到1float currentProgress = 1+currentHeight/headViewHeight;//如果当前百分比大于1了，将其设置为1，目的是让第一个状态的椭圆不再继续变大if (currentProgress>=1) {currentProgress = 1;}//如果当前的状态是放开刷新，并且已经记录y坐标if (state == RELEASE_TO_REFRESH && isRecord) {setSelection(0);//如果当前滑动的距离小于headerView的总高度if (-headViewHeight+offsetY/RATIO<0) {//将状态置为下拉刷新状态state = PULL_TO_REFRESH;//根据状态改变headerView，主要是更新动画和文字等信息changeHeaderByState(state);//如果当前y的位移值小于0，即为headerView隐藏了}else if (offsetY<=0) {//将状态变为donestate = DONE;stopAnim();//根据状态改变headerView，主要是更新动画和文字等信息changeHeaderByState(state);}}//如果当前状态为下拉刷新并且已经记录y坐标if (state == PULL_TO_REFRESH && isRecord) {setSelection(0);//如果下拉距离大于等于headerView的总高度if (-headViewHeight+offsetY/RATIO>=0) {//将状态变为放开刷新state = RELEASE_TO_REFRESH;//根据状态改变headerView，主要是更新动画和文字等信息changeHeaderByState(state);//如果当前y的位移值小于0，即为headerView隐藏了}else if (offsetY<=0) {//将状态变为donestate = DONE;//根据状态改变headerView，主要是更新动画和文字等信息changeHeaderByState(state);}}//如果当前状态为done并且已经记录y坐标if (state == DONE && isRecord) {//如果位移值大于0if (offsetY>=0) {//将状态改为下拉刷新状态state = PULL_TO_REFRESH;changeHeaderByState(state);}}//如果为下拉刷新状态if (state == PULL_TO_REFRESH) {//则改变headerView的padding来实现下拉的效果headView.setPadding(0,(int)(-headViewHeight+offsetY/RATIO) ,0,0);}//如果为放开刷新状态if (state == RELEASE_TO_REFRESH) {//改变headerView的padding值headView.setPadding(0,(int)(-headViewHeight+offsetY/RATIO) ,0, 0);}}break;//当用户手指抬起时case MotionEvent.ACTION_UP://如果当前状态为下拉刷新状态if (state == PULL_TO_REFRESH) {//平滑的隐藏headerViewthis.smoothScrollBy((int)(-headViewHeight+offsetY/RATIO)+headViewHeight, 500);//根据状态改变headerViewchangeHeaderByState(state);}//如果当前状态为放开刷新if (state == RELEASE_TO_REFRESH) {//平滑的滑到正好显示headerViewthis.smoothScrollBy((int)(-headViewHeight+offsetY/RATIO), 500);//将当前状态设置为正在刷新state = REFRESHING;//回调接口的onRefresh方法mOnRefreshListener.onRefresh();//根据状态改变headerViewchangeHeaderByState(state);}//这一套手势执行完，一定别忘了将记录y坐标的isRecord改为false，以便于下一次手势的执行isRecord = false;break;}}}return super.onTouchEvent(ev);}/*** 根据状态改变headerView的动画和文字显示* @param state*/private void changeHeaderByState(int state){switch (state) {case DONE://如果的隐藏的状态//设置headerView的padding为隐藏headView.setPadding(0, -headViewHeight, 0, 0);startAnim();break;case RELEASE_TO_REFRESH://当前状态为放开刷新break;case PULL_TO_REFRESH://当前状态为下拉刷新startAnim();break;case REFRESHING://当前状态为正在刷新break;default:break;}}/*** 测量View* @param child*/private void measureView(View child) {ViewGroup.LayoutParams p = child.getLayoutParams();if (p == null) {p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);}int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0, p.width);int lpHeight = p.height;int childHeightSpec;if (lpHeight > 0) {childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight,MeasureSpec.EXACTLY);} else {childHeightSpec = MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED);}child.measure(childWidthSpec, childHeightSpec);}/*** 开启动画*/public void startAnim(){ivBack1.startAnimation(backAnimation1);ivBack2.startAnimation(backAnimation2);ivSun.startAnimation(sunAnimation);ivWheel1.startAnimation(wheelAnimation);ivWheel2.startAnimation(wheelAnimation);}/*** 关闭动画*/public void stopAnim(){ivBack1.clearAnimation();ivBack2.clearAnimation();ivSun.clearAnimation();ivWheel1.clearAnimation();ivWheel2.clearAnimation();}}