Android中ScrollView中嵌套RecyclerView的完美解决办法

  import java.lang.reflect.Field;import com.loopj.android.http.BuildConfig;import android.content.Context;import android.graphics.Rect;import android.support.v4.view.ViewCompat;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.util.Log;import android.view.View;/** * 重写 LinearLayoutManager 为了ScrollView可以显示RecyclerView 垂直布局 * * @author M.Z */public class FullyLinearLayoutManager2 extends LinearLayoutManager {     private static boolean canMakeInsetsDirty = true;    private static Field insetsDirtyField = null;     private static final int CHILD_WIDTH = 0;    private static final int CHILD_HEIGHT = 1;    private static final int DEFAULT_CHILD_SIZE = 100;     private final int[] childDimensions = new int[2];    private final RecyclerView view;     private int childSize = DEFAULT_CHILD_SIZE;    private boolean hasChildSize;    private int overScrollMode = ViewCompat.OVER_SCROLL_ALWAYS;    private final Rect tmpRect = new Rect();     public FullyLinearLayoutManager2(Context context) {        super(context);        this.view = null;    }     public FullyLinearLayoutManager2(Context context, int orientation, boolean reverseLayout) {        super(context, orientation, reverseLayout);        this.view = null;    }     public FullyLinearLayoutManager2(RecyclerView view) {        super(view.getContext());        this.view = view;        this.overScrollMode = ViewCompat.getOverScrollMode(view);    }     public FullyLinearLayoutManager2(RecyclerView view, int orientation, boolean reverseLayout) {        super(view.getContext(), orientation, reverseLayout);        this.view = view;        this.overScrollMode = ViewCompat.getOverScrollMode(view);    }     public void setOverScrollMode(int overScrollMode) {        if (overScrollMode < ViewCompat.OVER_SCROLL_ALWAYS || overScrollMode > ViewCompat.OVER_SCROLL_NEVER)            throw new IllegalArgumentException("Unknown overscroll mode: " + overScrollMode);        if (this.view == null) throw new IllegalStateException("view == null");        this.overScrollMode = overScrollMode;        ViewCompat.setOverScrollMode(view, overScrollMode);    }     public static int makeUnspecifiedSpec() {        return View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);    }     @Override    public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) {        final int widthMode = View.MeasureSpec.getMode(widthSpec);        final int heightMode = View.MeasureSpec.getMode(heightSpec);         final int widthSize = View.MeasureSpec.getSize(widthSpec);        final int heightSize = View.MeasureSpec.getSize(heightSpec);         final boolean hasWidthSize = widthMode != View.MeasureSpec.UNSPECIFIED;        final boolean hasHeightSize = heightMode != View.MeasureSpec.UNSPECIFIED;         final boolean exactWidth = widthMode == View.MeasureSpec.EXACTLY;        final boolean exactHeight = heightMode == View.MeasureSpec.EXACTLY;         final int unspecified = makeUnspecifiedSpec();         if (exactWidth && exactHeight) {            // in case of exact calculations for both dimensions let's use default "onMeasure" implementation            super.onMeasure(recycler, state, widthSpec, heightSpec);            return;        }         final boolean vertical = getOrientation() == VERTICAL;         initChildDimensions(widthSize, heightSize, vertical);         int width = 0;        int height = 0;         // it's possible to get scrap views in recycler which are bound to old (invalid) adapter entities. This        // happens because their invalidation happens after "onMeasure" method. As a workaround let's clear the        // recycler now (it should not cause any performance issues while scrolling as "onMeasure" is never        // called whiles scrolling)        recycler.clear();         final int stateItemCount = state.getItemCount();        final int adapterItemCount = getItemCount();        // adapter always contains actual data while state might contain old data (f.e. data before the animation is        // done). As we want to measure the view with actual data we must use data from the adapter and not from  the        // state        for (int i = 0; i < adapterItemCount; i++) {            if (vertical) {                if (!hasChildSize) {                    if (i < stateItemCount) {                        // we should not exceed state count, otherwise we'll get IndexOutOfBoundsException. For such items                        // we will use previously calculated dimensions                        measureChild(recycler, i, widthSize, unspecified, childDimensions);                    } else {                        logMeasureWarning(i);                    }                }                height += childDimensions[CHILD_HEIGHT];                if (i == 0) {                    width = childDimensions[CHILD_WIDTH];                }                if (hasHeightSize && height >= heightSize) {                    break;                }            } else {                if (!hasChildSize) {                    if (i < stateItemCount) {                        // we should not exceed state count, otherwise we'll get IndexOutOfBoundsException. For such items                        // we will use previously calculated dimensions                        measureChild(recycler, i, unspecified, heightSize, childDimensions);                    } else {                        logMeasureWarning(i);                    }                }                width += childDimensions[CHILD_WIDTH];                if (i == 0) {                    height = childDimensions[CHILD_HEIGHT];                }                if (hasWidthSize && width >= widthSize) {                    break;                }            }        }         if (exactWidth) {            width = widthSize;        } else {            width += getPaddingLeft() + getPaddingRight();            if (hasWidthSize) {                width = Math.min(width, widthSize);            }        }         if (exactHeight) {            height = heightSize;        } else {            height += getPaddingTop() + getPaddingBottom();            if (hasHeightSize) {                height = Math.min(height, heightSize);            }        }         setMeasuredDimension(width, height);         if (view != null && overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS) {            final boolean fit = (vertical && (!hasHeightSize || height < heightSize))                    || (!vertical && (!hasWidthSize || width < widthSize));             ViewCompat.setOverScrollMode(view, fit ? ViewCompat.OVER_SCROLL_NEVER : ViewCompat.OVER_SCROLL_ALWAYS);        }    }     private void logMeasureWarning(int child) {        if (BuildConfig.DEBUG) {            Log.w("LinearLayoutManager", "Can't measure child #" + child + ", previously used dimensions will be reused." +                    "To remove this message either use #setChildSize() method or don't run RecyclerView animations");        }    }     private void initChildDimensions(int width, int height, boolean vertical) {        if (childDimensions[CHILD_WIDTH] != 0 || childDimensions[CHILD_HEIGHT] != 0) {            // already initialized, skipping            return;        }        if (vertical) {            childDimensions[CHILD_WIDTH] = width;            childDimensions[CHILD_HEIGHT] = childSize;        } else {            childDimensions[CHILD_WIDTH] = childSize;            childDimensions[CHILD_HEIGHT] = height;        }    }     @Override    public void setOrientation(int orientation) {        // might be called before the constructor of this class is called        //noinspection ConstantConditions        if (childDimensions != null) {            if (getOrientation() != orientation) {                childDimensions[CHILD_WIDTH] = 0;                childDimensions[CHILD_HEIGHT] = 0;            }        }        super.setOrientation(orientation);    }     public void clearChildSize() {        hasChildSize = false;        setChildSize(DEFAULT_CHILD_SIZE);    }     public void setChildSize(int childSize) {        hasChildSize = true;        if (this.childSize != childSize) {            this.childSize = childSize;            requestLayout();        }    }     private void measureChild(RecyclerView.Recycler recycler, int position, int widthSize, int heightSize, int[] dimensions) {        final View child;        try {            child = recycler.getViewForPosition(position);        } catch (IndexOutOfBoundsException e) {            if (BuildConfig.DEBUG) {                Log.w("LinearLayoutManager", "LinearLayoutManager doesn't work well with animations. Consider switching them off", e);            }            return;        }         final RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) child.getLayoutParams();         final int hPadding = getPaddingLeft() + getPaddingRight();        final int vPadding = getPaddingTop() + getPaddingBottom();         final int hMargin = p.leftMargin + p.rightMargin;        final int vMargin = p.topMargin + p.bottomMargin;         // we must make insets dirty in order calculateItemDecorationsForChild to work        makeInsetsDirty(p);        // this method should be called before any getXxxDecorationXxx() methods        calculateItemDecorationsForChild(child, tmpRect);         final int hDecoration = getRightDecorationWidth(child) + getLeftDecorationWidth(child);        final int vDecoration = getTopDecorationHeight(child) + getBottomDecorationHeight(child);         final int childWidthSpec = getChildMeasureSpec(widthSize, hPadding + hMargin + hDecoration, p.width, canScrollHorizontally());        final int childHeightSpec = getChildMeasureSpec(heightSize, vPadding + vMargin + vDecoration, p.height, canScrollVertically());         child.measure(childWidthSpec, childHeightSpec);         dimensions[CHILD_WIDTH] = getDecoratedMeasuredWidth(child) + p.leftMargin + p.rightMargin;        dimensions[CHILD_HEIGHT] = getDecoratedMeasuredHeight(child) + p.bottomMargin + p.topMargin;         // as view is recycled let's not keep old measured values        makeInsetsDirty(p);        recycler.recycleView(child);    }     private static void makeInsetsDirty(RecyclerView.LayoutParams p) {        if (!canMakeInsetsDirty) {            return;        }        try {            if (insetsDirtyField == null) {                insetsDirtyField = RecyclerView.LayoutParams.class.getDeclaredField("mInsetsDirty");                insetsDirtyField.setAccessible(true);            }            insetsDirtyField.set(p, true);        } catch (NoSuchFieldException e) {            onMakeInsertDirtyFailed();        } catch (IllegalAccessException e) {            onMakeInsertDirtyFailed();        }    }     private static void onMakeInsertDirtyFailed() {        canMakeInsetsDirty = false;        if (BuildConfig.DEBUG) {            Log.w("LinearLayoutManager", "Can't make LayoutParams insets dirty, decorations measurements might be incorrect");        }    }}

使用：

recyclerView.setLayoutManager(new FullyLinearLayoutManager(getActivity(),LinearLayoutManager.VERTICAL, false));

最后RecyclerView外层嵌套一层

重写ScrollView

import android.content.Context;import android.os.Handler;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.ViewConfiguration;import android.widget.ScrollView;/** * @author 作者 zxb: * @date 创建时间：2016年7月27日 * @Description 带监听滚动的scrollview */public class MyScrollView extends ScrollView {private int downX;private int downY;private int mTouchSlop;private OnScrollListener onScrollListener;/** * 主要是用在用户手指离开MyScrollView，MyScrollView还在继续滑动，我们用来保存Y的距离，然后做比较 */private int lastScrollY;public MyScrollView(Context context) {this(context, null);mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();}public MyScrollView(Context context, AttributeSet attrs) {this(context, attrs, 0);mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();}public MyScrollView(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();}/** * 设置滚动接口 * * @param onScrollListener */public void setOnScrollListener(OnScrollListener onScrollListener) {this.onScrollListener = onScrollListener;}/** * 用于用户手指离开MyScrollView的时候获取MyScrollView滚动的Y距离，然后回调给onScroll方法中 */private Handler handler = new Handler() {public void handleMessage(android.os.Message msg) {int scrollY = MyScrollView.this.getScrollY();// 此时的距离和记录下的距离不相等，在隔5毫秒给handler发送消息if (lastScrollY != scrollY) {lastScrollY = scrollY;handler.sendMessageDelayed(handler.obtainMessage(), 5);}if (onScrollListener != null) {onScrollListener.onScroll(scrollY);}};};/** * 重写onTouchEvent， 当用户的手在MyScrollView上面的时候， * 直接将MyScrollView滑动的Y方向距离回调给onScroll方法中，当用户抬起手的时候， * MyScrollView可能还在滑动，所以当用户抬起手我们隔5毫秒给handler发送消息，在handler处理 * MyScrollView滑动的距离 */@Overridepublic boolean onTouchEvent(MotionEvent ev) {if (onScrollListener != null) {onScrollListener.onScroll(lastScrollY = this.getScrollY());}switch (ev.getAction()) {case MotionEvent.ACTION_UP:handler.sendMessageDelayed(handler.obtainMessage(), 5);break;}return super.onTouchEvent(ev);}/** * * 滚动的回调接口 * * @author xiaanming * */public interface OnScrollListener {/** * 回调方法， 返回MyScrollView滑动的Y方向距离 * * @param scrollY *            、 */public void onScroll(int scrollY);}@Overridepublic boolean onInterceptTouchEvent(MotionEvent e) {int action = e.getAction();switch (action) {case MotionEvent.ACTION_DOWN:downX = (int) e.getRawX();downY = (int) e.getRawY();break;case MotionEvent.ACTION_MOVE:int moveY = (int) e.getRawY();if (Math.abs(moveY - downY) > mTouchSlop) {return true;}}return super.onInterceptTouchEvent(e);}}

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