Android自定义下拉刷新控件RefreshableView

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:orientation="horizontal"> <ImageView android:id="@+id/imageView_down" android:layout_width="14dp" android:layout_height="24dp" android:padding="2dp" android:src="@drawable/svg_down" /> <ProgressBar android:visibility="gone" android:id="@+id/progressBar" style="?android:attr/progressBarStyle" android:layout_width="20dp" android:layout_height="20dp" android:progressDrawable="@drawable/progressBar" /> <TextView android:padding="15dp" android:id="@+id/textView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/pull_to_refresh" android:textSize="16sp" /></LinearLayout>

package com.pull2refresh;import android.animation.ObjectAnimator;import android.animation.ValueAnimator;import android.annotation.TargetApi;import android.content.Context;import android.os.Build;import android.util.AttributeSet;import android.util.Log;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.ViewConfiguration;import android.view.ViewGroup;import android.view.animation.RotateAnimation;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.ProgressBar;import android.widget.TextView;import shike.xianrou.com.pull2refresh.R;/** * Created by cjh on 16-9-6. */public class RefreshableView extends LinearLayout implements View.OnTouchListener { private static final String TAG = "RefreshableView"; private static final int REFRESHING = 0;//正在刷新 private static final int ORIGINAL = REFRESHING + 1;//初始状态 private static final int RELEASE_TO_REFRESHING = ORIGINAL + 1;//释放即将刷新的状态 private int current_status = ORIGINAL;//当前最新状态 private LinearLayout headView;//刷新layout private TextView textView;//刷新layout中的文字提示 private ImageView imageView;//刷新layout中的箭头 private ProgressBar progressBar;//刷新layout中的进度条 private View view;//手指控制的下拉的View private int hideHeight;//刷新layout要隐藏的高度 private boolean isablePull;//是否可以下拉，例如当 current_status = REFRESHIING 时是不可以下拉拖拽的 private float yDown;//手指按下的坐标 private int touchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop();//界限值，防止手指误触，过于灵敏 private boolean firstLayout = true;//第一次调用onLayout的时候置为false private int maxMarginTop;//刷新Layout能拉下的最大距离 private MarginLayoutParams marginLayoutParams;//刷新layout的MarginLayoutParams private String pull_to_refresh = "下拉可以刷新"; private String release_to_refresh = "释放立即刷新"; private String refreshing = "正在刷新…"; private int original_margin = 0;//针对下拉的View存在MarginTop这中特殊值的处理 public interface PullToRefreshListener { void onRefresh(); } private PullToRefreshListener pullToRefreshListener; public void addPullToRefreshListener(PullToRefreshListener pullToRefreshListener) { this.pullToRefreshListener = pullToRefreshListener; } public RefreshableView(Context context) { super(context); init(); } public RefreshableView(Context context, AttributeSet attrs) { super(context, attrs); init(); } public RefreshableView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(); } @TargetApi(Build.VERSION_CODES.LOLLIPOP) public RefreshableView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); init(); } private void init() { headView = (LinearLayout) LayoutInflater.from(getContext()).inflate(R.layout.refresh_layout, null, true); imageView = (ImageView) headView.findViewById(R.id.imageView_down); progressBar = (ProgressBar) headView.findViewById(R.id.progressBar); textView = (TextView) headView.findViewById(R.id.textView); progressBar.setVisibility(View.GONE); setOrientation(VERTICAL); addView(headView, 0); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); Log.d(TAG, "onlayout"); if (changed && firstLayout) {  //将View的Touch时间的处理交给RefreshableView去处理  view = getChildAt(1);  view.setOnTouchListener(this);  //刷新layout的 marginTop 的最大值设为刷新头的高度  maxMarginTop = headView.getHeight();  //要将控件完全隐藏起来，那么隐藏的高度就设置为控件的高度  hideHeight = -headView.getHeight();  marginLayoutParams = (MarginLayoutParams) headView.getLayoutParams();  marginLayoutParams.topMargin = hideHeight;  headView.setLayoutParams(marginLayoutParams);  //这里必须将firstLayout设置为false,否则在处理Touch是件的过程中，headView在怎么调用setLayoutParams都会被置为初始的隐藏状态  firstLayout = false;  //如果子View是一个ViewGroup 那么就需要计算出子View的MarginTop的值，因为如果MarginTop不为0，那么子View的Y轴坐标和父View的坐标是不一样的  if (view instanceof ViewGroup) {  int[] childLocations = new int[2];  int[] viewLocations = new int[2];  view.getLocationOnScreen(viewLocations);  ((ViewGroup) view).getChildAt(0).getLocationOnScreen(childLocations);  original_margin = childLocations[1] - viewLocations[1];  Log.d(TAG, "onLayout viewLocations[1] " + viewLocations[1]);  Log.d(TAG, "onLayout locations[1] " + childLocations[1]);  Log.d(TAG, "onLayout original_margin " + original_margin);  } } } @Override public boolean onTouch(View view, MotionEvent motionEvent) { if (pullToRefreshListener != null) {  isAblePull();  if (isablePull) {  switch (motionEvent.getAction()) {   case MotionEvent.ACTION_DOWN:   yDown = motionEvent.getRawY();   break;   case MotionEvent.ACTION_MOVE:   float yMove = motionEvent.getRawY();   float distance = yMove - yDown;   //如果手势是向上的，并且手势在Y轴的移动距离小于界限值，那么就不处理   if (distance < 0 || Math.abs(distance) < touchSlop)    return false;   //MarginTop的距离是手势距离的1/2,形成费力延迟的效果   marginLayoutParams.topMargin = (int) (distance / 2 + hideHeight);   Log.d(TAG, "topMargin " + marginLayoutParams.topMargin);   //如果大于最大的MarginTop的值的时候，就将值置为 maxMarginTop   if (marginLayoutParams.topMargin >= maxMarginTop)    marginLayoutParams.topMargin = maxMarginTop;   if (marginLayoutParams.topMargin >= 0) {    //当刷新头完全显示的时候，改变状态，置为 释放刷新的状态    if (current_status != RELEASE_TO_REFRESHING) {    rotate(0, 180);    textView.setText(release_to_refresh);    }    current_status = RELEASE_TO_REFRESHING;   } else {    //否则就置为初始状态    if (current_status != ORIGINAL) {    rotate(180, 360);    textView.setText(pull_to_refresh);    }    current_status = ORIGINAL;   }   headView.setLayoutParams(marginLayoutParams);   break;   case MotionEvent.ACTION_CANCEL:   case MotionEvent.ACTION_UP:   float yUp = motionEvent.getRawY();   float dis = yUp - yDown;   if (dis > 0 && Math.abs(dis) > touchSlop)    switch (current_status) {    //释放刷新    case RELEASE_TO_REFRESHING:     animateMarginTop(marginLayoutParams.topMargin, 0);     imageView.clearAnimation();     imageView.setVisibility(View.GONE);     progressBar.setVisibility(View.VISIBLE);     textView.setText(refreshing);     pullToRefreshListener.onRefresh();     break;    //初始化    case ORIGINAL:     reset();     //从当前的MarginTop的值，转变到隐藏所需的 MarginTop     animateMarginTop(marginLayoutParams.topMargin, hideHeight);     break;    }   else    return false;   break;  }  return true;  } } return false; } /** * 判断是否可以下拉 * * @return */ public boolean isAblePull() { //统一判断，其实主要是对于view是普通View的判断 if (current_status != REFRESHING)  isablePull = true; else  isablePull = false; if (view instanceof ViewGroup) {  isablePull = false;  View childView = ((ViewGroup) view).getChildAt(0);  int[] viewLocations = new int[2];  int[] childViewLocations = new int[2];  view.getLocationOnScreen(viewLocations);  childView.getLocationOnScreen(childViewLocations);  //这一步中的 original_margin 至关重要，就是用来兼容 子View 有MarginTop属性的值，当childView 的Y轴坐标 和 计算出了 Margin 值后的父View坐标相等时，说明此时处于可下拉的状态  if (viewLocations[1] + original_margin == childViewLocations[1])  isablePull = true;  else  isablePull = false; } return isablePull; } private void rotate(int from, int to) { RotateAnimation rotateAnimation = new RotateAnimation(from, to, imageView.getWidth() / 2, imageView.getHeight() / 2); rotateAnimation.setDuration(100); rotateAnimation.setFillAfter(true); imageView.startAnimation(rotateAnimation); } private void animateMarginTop(int from, int to) { ObjectAnimator objectAnimator = ObjectAnimator.ofInt(headView, "cjh", from, to); objectAnimator.setDuration(300); objectAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {  @Override  public void onAnimationUpdate(ValueAnimator valueAnimator) {  int margin = (int) valueAnimator.getAnimatedValue();  marginLayoutParams.topMargin = margin;  headView.setLayoutParams(marginLayoutParams);  } }); objectAnimator.start(); } public void complete() { animateMarginTop(0, hideHeight); reset(); } private void reset() { rotate(180, 360); textView.setText(pull_to_refresh); imageView.setVisibility(View.VISIBLE); progressBar.setVisibility(View.GONE); }}

 <com.pull2refresh.RefreshableView android:id="@+id/refreshableView" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center"> <com.pull2refresh.MTextView  android:id="@+id/mTextView"  android:layout_width="match_parent"  android:layout_height="100dp"  android:background="@color/colorPrimary"  android:gravity="center"  android:text="Hello World!"  android:textSize="22sp" /> </com.pull2refresh.RefreshableView>

... refreshableView.addPullToRefreshListener(new RefreshableView.PullToRefreshListener() {  @Override  public void onRefresh() {  setData();  } });... private void setData() { ObjectAnimator objectAnimator = ObjectAnimator.ofFloat(textView, "text", 1f, 100f); objectAnimator.setDuration(3000); objectAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {  @Override  public void onAnimationUpdate(ValueAnimator valueAnimator) {  textView.setText((Float) valueAnimator.getAnimatedValue());  } }); objectAnimator.addListener(new Animator.AnimatorListener() {  @Override  public void onAnimationStart(Animator animator) {  }  @Override  public void onAnimationEnd(Animator animator) {  refreshableView.complete();  }  @Override  public void onAnimationCancel(Animator animator) {  }  @Override  public void onAnimationRepeat(Animator animator) {  } }); objectAnimator.start(); }