本文为大家分享了Android实现RecyclerView下拉刷新效果的具体代码，供大家参考，具体内容如下
思路
RealPullRefreshView继承了一个LinearLayout 里面放置了一个刷新头布局，将其margin_top设置为负的刷新头的高度的 再添加一个RecyclerView 触摸事件分发机制，当在特定条件下让RealPullRefreshView拦截触摸事件，否则的话，不拦截，让RecyclerView自己去处理触摸事件 在手指下拉时，定义好不同的状态STATE,在不同状态下，处理不同的显示，这里讲不同状态下的刷新头如何显示，抽象为一个接口，用户可以实现这个接口，自定义刷新头的布局和动画 加载更多的功能是利用RecyclerView的多type布局实现的 难点在于触摸事件的拦截，和认真处理各种滑动的问题
使用
xml
<com.example.apple.quickdemo.realview.view.RealPullRefreshView android:id="@+id/real_pull_refresh_view" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" app:refresh_header_view="@layout/headerview"/>
这是headerview
<?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="50dp" android:background="#ff0" android:orientation="horizontal" android:gravity="center"> <TextView android:layout_width="wrap_content" android:layout_height="match_parent" android:background="@color/colorAccent" android:visibility="visible" android:id="@+id/tv" android:gravity="center" android:text="下拉刷新" android:textSize="21sp"/> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@mipmap/ic_launcher" android:id="@+id/iv" /> </LinearLayout>
代码
mRealPullRefreshView.setLayoutManager(mLayoutManager); mRealPullRefreshView.setAdapter(mMyAdapte); //用户可以自定义自己的刷新头布局和动画 //mRealPullRefreshView.setOnPullShowViewListener(new GifOnPullShowViewListerner(mRealPullRefreshView)); mRealPullRefreshView.setOnPullListener(new RealPullRefreshView.OnPullListener() { @Override public void onRefresh() { mHandler.postDelayed(new Runnable() { @Override public void run() { mBodies.add(0, new Body("新数据"+i++,100)); mRealPullRefreshView.refreshFinish(); } }, 3000); } @Override public void onLoadMore() { final List<Body> more=new ArrayList<Body>(); mHandler.postDelayed(new Runnable() { @Override public void run() { for (int i = 0; i < 3; i++) { more.add(new Body("more+++"+i,100)); } mBodies.addAll(more); mRealPullRefreshView.loadMreFinish(); } }, 1500); } });
自定义刷新头布局和动画
package com.example.apple.quickdemo.realview.show; import android.animation.ObjectAnimator; import android.animation.ValueAnimator; import android.util.Log; import android.view.View; import android.widget.ImageView; import android.widget.TextView; import com.example.apple.quickdemo.R; import com.example.apple.quickdemo.realview.view.RealPullRefreshView; /** * Created by apple on 2017/7/9. */ public class ImplOnPullShowViewListener implements RealPullRefreshView.OnPullShowViewListener { private TextView mTv; private ImageView mIv; private ObjectAnimator mAni; View mHeaderView; public ImplOnPullShowViewListener(RealPullRefreshView realPullRefreshView) { mHeaderView = realPullRefreshView.getRefreshHeaderView(); mTv = (TextView) mHeaderView.findViewById(R.id.tv); mIv = (ImageView) mHeaderView.findViewById(R.id.iv); mAni = ObjectAnimator.ofFloat(mIv, "rotation", -15, 15).setDuration(300); mAni.setRepeatCount(ValueAnimator.INFINITE); mAni.setRepeatMode(ValueAnimator.REVERSE); } @Override public void onPullDownRefreshState(int scrollY, int headviewHeight,int deltaY) { mTv.setText("下拉刷新"); float f = -((float) scrollY / (float) headviewHeight); Log.e("tag", f+ ""); Log.e("tag", -scrollY + "scrollY"); mIv.setScaleX(f); mIv.setScaleY(f); } @Override public void onReleaseRefreshState(int scrollY, int deltaY) { mTv.setText("松手刷新"); } @Override public void onRefreshingState() { mTv.setText("正在刷新"); mIv.setScaleX(1.0f); mIv.setScaleY(1.0f); mAni.start(); } @Override public void onDefaultState() { if (mAni.isRunning()){ mAni.end(); mIv.setRotation(0); } } }
源码
package com.example.apple.quickdemo.realview.view; import android.content.Context; import android.content.res.TypedArray; import android.support.annotation.Nullable; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.StaggeredGridLayoutManager; import android.util.AttributeSet; import android.util.Log; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.VelocityTracker; import android.view.View; import android.view.ViewGroup; import android.widget.LinearLayout; import android.widget.Scroller; import android.widget.Toast; import com.example.apple.quickdemo.R; import com.example.apple.quickdemo.realview.show.ImplOnPullShowViewListener; import static android.content.ContentValues.TAG; /** * Created by apple on 2017/7/7. * 下拉刷新 */ public class RealPullRefreshView extends LinearLayout { private int mTouchSlop; // 分别记录上次滑动的坐标 private int mLastX = 0; private int mLastY = 0; // 分别记录上次滑动的坐标(onInterceptTouchEnvent) private int mLastXIntercept = 0; private int mLastYIntercept = 0; private Scroller mScroller; private VelocityTracker mVelocityTracker; private RecyclerView.Adapter mAdapter; public RecyclerView getRecyclerView() { return mRecyclerView; } private RecyclerView mRecyclerView; private int DEFAULT = 0; private final int PULL_DOWN_REFRESH = 1; private final int RELEASE_REFRESH = 2; private final int REFRESHING = 3; private final int LOAD_MORE = 4; private int STATE = DEFAULT; private int rfreshHeaderWidth; private int refreshHeadviewHeight; private OnPullListener mOnPullListener; private View mRefreshHeaderView; private RecyclerView.LayoutManager mLayoutManager; int refreshHeadviewId; public void setLayoutManager(RecyclerView.LayoutManager manager) { this.mLayoutManager = manager; mRecyclerView.setLayoutManager(mLayoutManager); } public void setAdapter(RecyclerView.Adapter adapter) { this.mAdapter = adapter; mRecyclerView.setAdapter(mAdapter); } public View getRefreshHeaderView() { return mRefreshHeaderView; } public void setOnPullShowViewListener(OnPullShowViewListener onPullShowViewListener) { mOnPullShowViewListener = onPullShowViewListener; } private OnPullShowViewListener mOnPullShowViewListener; public void setOnPullListener(OnPullListener onPullListener) { mOnPullListener = onPullListener; } public RealPullRefreshView(Context context) { super(context); initView(context); } public RealPullRefreshView(Context context, @Nullable AttributeSet attrs) { super(context, attrs); initAttrs(context, attrs); // ★★★★★一个坑initAttrs方法里的typedArray去获取属性时，第一次获取的属性全是0，他会马上重走一次构造方法，再次获取一次，才能获得正确的值 // 如果第一次获取的值为0，则不去initView if (refreshHeadviewId != 0) { initView(context); } } public RealPullRefreshView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); initAttrs(context, attrs); if (refreshHeadviewId != 0) { initView(context); } } private void initAttrs(Context context, AttributeSet attrs) { TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.RealPullRefreshView); try { refreshHeadviewId = typedArray.getResourceId(R.styleable.RealPullRefreshView_refresh_header_view, 0); } finally { typedArray.recycle(); } } private void initView(Context context) { mScroller = new Scroller(getContext()); mVelocityTracker = VelocityTracker.obtain(); // 添加headerview // ★ ★ ★ ★ ★ 注意不要用这个方法inflate布局，会导致layout的所有属性失效，height、width、margin // 原因见 http://blog.csdn.net/zhaokaiqiang1992/article/details/36006467 // ★ ★ ★ ★ ★ mRefreshHeaderView = mInflater.inflate(R.layout.headerview, null); mRefreshHeaderView = LayoutInflater.from(context).inflate(refreshHeadviewId, this, false); addView(mRefreshHeaderView); // } // 以下代码主要是为了设置头布局的marginTop值为-headerviewHeight // 注意必须等到一小会才会得到正确的头布局宽高 postDelayed(new Runnable() { @Override public void run() { Log.e("q11", refreshHeadviewHeight + "qqqqqqqqqq " + mRefreshHeaderView.getHeight()); rfreshHeaderWidth = mRefreshHeaderView.getWidth(); refreshHeadviewHeight = mRefreshHeaderView.getHeight(); MarginLayoutParams lp = new LinearLayout.LayoutParams(rfreshHeaderWidth, refreshHeadviewHeight); lp.setMargins(0, -refreshHeadviewHeight, 0, 0); mRefreshHeaderView.setLayoutParams(lp); } }, 100); // 添加RecyclerView mRecyclerView = new RecyclerView(context); addView(mRecyclerView, LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT); // 这里我提供了一个默认的显示效果，如果用户不使用mRealPullRefreshView.setOnPullShowViewListener的话，会默认使用这个 // 用户可以实现OnPullShowViewListener接口，去实现自己想要的显示效果 mOnPullShowViewListener = new ImplOnPullShowViewListener(this); setLoadMore(); } private void setLoadMore() { // 当目前的可见条目是所有数据的最后一个时，开始加载新的数据 mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() { @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { super.onScrolled(recyclerView, dx, dy); int lastCompletelyVisibleItemPosition = -1; if (mLayoutManager instanceof LinearLayoutManager) { LinearLayoutManager manager = (LinearLayoutManager) mLayoutManager; lastCompletelyVisibleItemPosition = manager.findLastVisibleItemPosition(); } else if (mLayoutManager instanceof GridLayoutManager) { GridLayoutManager manager = (GridLayoutManager) mLayoutManager; lastCompletelyVisibleItemPosition = manager.findLastVisibleItemPosition(); } else if (mLayoutManager instanceof StaggeredGridLayoutManager) { StaggeredGridLayoutManager manager = (StaggeredGridLayoutManager) mLayoutManager; lastCompletelyVisibleItemPosition = manager.findLastVisibleItemPositions(new int[manager.getSpanCount()])[0]; } if (lastCompletelyVisibleItemPosition + 1 == mAdapter.getItemCount()) { if (mOnPullListener != null && STATE == DEFAULT) { STATE = LOAD_MORE; mOnPullListener.onLoadMore(); } } } }); } @Override public boolean onInterceptTouchEvent(MotionEvent event) { boolean intercepted = false; int x = (int) event.getX(); int y = (int) event.getY(); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: { intercepted = false; /*if (STATE!=DEFAULT||STATE!=REFRESHING){ if (!mScroller.isFinished()) { mScroller.abortAnimation(); }}*/ break; } case MotionEvent.ACTION_MOVE: { int deltaX = x - mLastXIntercept; int deltaY = y - mLastYIntercept; int firstCompletelyVisibleItemPosition = -1; if (mLayoutManager instanceof LinearLayoutManager) { LinearLayoutManager manager = (LinearLayoutManager) mLayoutManager; firstCompletelyVisibleItemPosition = manager.findFirstCompletelyVisibleItemPosition(); } else if (mLayoutManager instanceof GridLayoutManager) { GridLayoutManager manager = (GridLayoutManager) mLayoutManager; firstCompletelyVisibleItemPosition = manager.findFirstCompletelyVisibleItemPosition(); } else if (mLayoutManager instanceof StaggeredGridLayoutManager) { StaggeredGridLayoutManager manager = (StaggeredGridLayoutManager) mLayoutManager; firstCompletelyVisibleItemPosition = manager.findFirstCompletelyVisibleItemPositions(new int[manager.getSpanCount()])[0]; } // ******************这里说明什么规则下，拦截，其余代码不要动了，其余代码指的是处理滑动冲突的代码*************** if (firstCompletelyVisibleItemPosition == 0 && deltaY > 0 && Math.abs(deltaY) > Math.abs(deltaX)) {//拉倒最顶部，继续往下拉，将拉出头布局，要父布局拦截 intercepted = true; } else if (getScrollY() < 0) {//表示头布局已经向下拉出来，头布局已经显示了，要父布局拦截 intercepted = true; } else if (deltaY < 0) { intercepted = false;//不要父布局拦截了 } else { intercepted = false;//不要父布局拦截了 } // ******************什么规则下，拦截*************** break; } case MotionEvent.ACTION_UP: { intercepted = false; break; } default: break; } Log.d(TAG, "intercepted=" + intercepted); mLastX = x; mLastY = y; mLastXIntercept = x; mLastYIntercept = y; return intercepted; } /** * 下面不同布局，不同的滑动需求 * * @param event * @return */ @Override public boolean onTouchEvent(MotionEvent event) { mVelocityTracker.addMovement(event); int x = (int) event.getX(); int y = (int) event.getY(); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: { if (!mScroller.isFinished()) { mScroller.abortAnimation(); } break; } case MotionEvent.ACTION_MOVE: { int deltaX = x - mLastX; int deltaY = y - mLastY; if (getScrollY() > 0) { //防止在正在刷新状态下，上拉出空白 } else if (getScrollY() <= 0 && getScrollY() > -refreshHeadviewHeight * 5) { // 最多下拉到头布局高度5倍的距离 scrollBy(0, -deltaY / 2); } if (getScrollY() > -refreshHeadviewHeight && STATE != REFRESHING) {//头布局显示不全时，为下拉刷新PULL_DOWN_REFRESH状态 STATE = PULL_DOWN_REFRESH; if (mOnPullShowViewListener != null) { mOnPullShowViewListener.onPullDownRefreshState(getScrollY(), refreshHeadviewHeight, deltaY); } } if (getScrollY() < -refreshHeadviewHeight && STATE != REFRESHING) {//头布局完全显示时，为释放刷新RELEASE_REFRESH状态 STATE = RELEASE_REFRESH; if (mOnPullShowViewListener != null) { mOnPullShowViewListener.onReleaseRefreshState(getScrollY(), deltaY); } } break; } case MotionEvent.ACTION_UP: { final int scrollY = getScrollY(); //松手时，根据所处的状态，让布局滑动到不同的地方，做不同的操作 switch (STATE) { case PULL_DOWN_REFRESH: STATE = DEFAULT; //头布局没有完全显示，完全隐藏头布局 smoothScrollBy(0, -scrollY); break; case RELEASE_REFRESH: STATE = REFRESHING; smoothScrollBy(0, -refreshHeadviewHeight - scrollY); if (mOnPullShowViewListener != null) { mOnPullShowViewListener.onRefreshingState(); } if (mOnPullListener != null) { mOnPullListener.onRefresh(); } break; case REFRESHING: if (getScrollY() < -refreshHeadviewHeight) { smoothScrollBy(0, -refreshHeadviewHeight - scrollY); } else { smoothScrollBy(0, -scrollY); } break; } mVelocityTracker.clear(); break; } default: break; } mLastX = x; mLastY = y; return true; } /** * 当用户使用完下拉刷新回调时，需要调用此方法，将头不去隐藏，将STATE恢复 */ public void refreshFinish() { smoothScrollBy(0, 0 - getScrollY()); getRecyclerView().getAdapter().notifyDataSetChanged(); STATE = DEFAULT; if (mOnPullShowViewListener != null) { mOnPullShowViewListener.onDefaultState(); } Toast.makeText(getContext(), "刷新成功!", Toast.LENGTH_SHORT).show(); } /** * 当用户使用完加载更多后回调时，需要调用此方法，将STATE恢复 */ public void loadMreFinish() { getRecyclerView().getAdapter().notifyDataSetChanged(); STATE = DEFAULT; Toast.makeText(getContext(), "加载成功了!", Toast.LENGTH_SHORT).show(); } /** * 在500毫秒内平滑地滚动多少像素点 * * @param dx * @param dy */ private void smoothScrollBy(int dx, int dy) { mScroller.startScroll(0, getScrollY(), 0, dy, 500); invalidate(); } @Override public void computeScroll() { if (mScroller.computeScrollOffset()) { scrollTo(mScroller.getCurrX(), mScroller.getCurrY()); postInvalidate(); } } /** * 释放资源 */ @Override protected void onDetachedFromWindow() { mVelocityTracker.recycle(); super.onDetachedFromWindow(); } // *************** // ***************** /** * 回调接口 */ public interface OnPullListener { /** * 当下拉刷新正在刷新时，这时候可以去请求数据，记得最后调用refreshFinish()复位 */ void onRefresh(); /** * 当加载更多时 */ void onLoadMore(); } /** * 回调接口，可以通过下面的回调，自定义各种状态下的显示效果 * 可以根据下拉距离scrollY设计动画效果 */ public interface OnPullShowViewListener { /** * 当处于下拉刷新时，头布局显示效果 * * @param scrollY 下拉的距离 * @param headviewHeight 头布局高度 * @param deltaY moveY-lastMoveY,正值为向下拉 */ void onPullDownRefreshState(int scrollY, int headviewHeight, int deltaY); /** * 当处于松手刷新时，头布局显示效果 * * @param scrollY 下拉的距离 * @param deltaY moveY-lastMoveY,正值为向下拉 */ void onReleaseRefreshState(int scrollY, int deltaY); /** * 正在刷新时，页面的显示效果 */ void onRefreshingState(); /** * 默认状态时，页面显示效果，主要是为了复位各种状态 */ void onDefaultState(); } }
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。