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
	 */
	@Override
	public 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);
	}
	@Override
	public 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);
	}
}