Java RecyclerView.getChildPosition方法代碼示例

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        final int totalSpanCount = getSpanCount(parent);
        final int itemPosition = parent.getChildPosition(view);

        final boolean isLeft = isLeft(view, totalSpanCount);
        final boolean isRight = isRight(view, totalSpanCount);
        final boolean isFull = isFull(view, totalSpanCount);
        final boolean isCenter = !isLeft && !isRight && !isFull;
        final boolean isTop = isTop(parent, itemPosition, totalSpanCount);
        final boolean isBottom = isBottom(parent, itemPosition, totalSpanCount);

//        LogUtil.d(itemPosition, "total:"+totalSpanCount, "index:"+getSpanIndex(view), "Size:"+getSpanSize(view), isLeft, isTop, isRight, isBottom, isFull, isCenter);

        final int left = (isRight || isCenter) ? mHalfSpacingWidth : 0;
        final int right = (isLeft || isCenter) ? mHalfSpacingWidth : 0;
        final int top = !isTop ? mHalfSpacingHeight : 0;
        final int bottom = !isBottom ? mHalfSpacingHeight : 0;

        outRect.set(left, top, right, bottom);
    }
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
                           RecyclerView.State state) {
    super.getItemOffsets(outRect, view, parent, state);
    if (mDivider == null) {
        return;
    }
    if (parent.getChildPosition(view) < 1) {
        return;
    }

    if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
        outRect.top = mDivider.getIntrinsicHeight();
    } else {
        outRect.left = mDivider.getIntrinsicWidth();
    }
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
    if (mFirstSpace != 0) {
        if (0 == parent.getChildPosition(view)) {
            if (LinearLayoutManager.HORIZONTAL == mScroller.getOrientation()) {
                outRect.left = mFirstSpace;
            } else {
                outRect.top = mFirstSpace;
            }
        }
    }

    if (mLastSpace != 0) {
        View nativeView = mScroller.getNativeView();
        ScrollerImp s;
        if (nativeView instanceof ScrollerStickyParent) {
            s = (ScrollerImp)((ScrollerStickyParent)nativeView).getChildAt(0);
        } else {
            s = (ScrollerImp)mScroller.getNativeView();
        }
        RecyclerView.Adapter adapter = s.getAdapter();
        if (null != adapter) {
            int count = adapter.getItemCount();
            if ((count - 1) == parent.getChildPosition(view)) {
                if (LinearLayoutManager.HORIZONTAL == mScroller.getOrientation()) {
                    outRect.right = mLastSpace;
                } else {
                    outRect.bottom = mLastSpace;
                }
            }
        }
    }
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public void getItemOffsets(Rect outRect, View view,
                           RecyclerView parent, RecyclerView.State state) {
    if (parent.getChildPosition(view) != parent.getAdapter().getItemCount() - 1)
        outRect.right = space;
    if (parent.getChildPosition(view) != 0)
        outRect.left = space;
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {

    // Add top margin only for the first item to avoid double space between items
    if(parent.getChildPosition(view) != 0)
        outRect.left = space;
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
    if(parent.getChildPosition(view)!=0){
        outRect.top = space;
    }
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
private void updatePosBasedOnReferenceList(RecyclerView referenceRv) {
    View firstVisibleView = referenceRv.getChildAt(0);
    int actual = referenceRv.getChildPosition(firstVisibleView);
    ((LinearLayoutManager) indexList.getLayoutManager()).scrollToPositionWithOffset(actual, firstVisibleView.getTop() + 0);
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView rv, RecyclerView.State state) {
    super.getItemOffsets(outRect, view, rv, state);

    debugLog("getItemOffsets");

    debugLog("View top = " + view.getTop());
    if (selectedDragItemPos != -1) {
        int itemPos = rv.getChildPosition(view);
        debugLog("itemPos =" + itemPos);

        if (!canDragOver(itemPos)) {
            return;
        }

        if (itemPos == selectedDragItemPos) {
            view.setVisibility(View.INVISIBLE);
        } else {
            //Make view visible incase invisible
            view.setVisibility(View.VISIBLE);

            //Find middle of the floatingItem
            float floatMiddleY = floatingItemBounds.top + floatingItemBounds.height() / 2;

            //Moving down the list
            //These will auto-animate if the device continually sends touch motion events
            // if (totalMovment>0)
            {
                if ((itemPos > selectedDragItemPos) && (view.getTop() < floatMiddleY)) {
                    float amountUp = (floatMiddleY - view.getTop()) / (float) view.getHeight();
                    //  amountUp *= 0.5f;
                    if (amountUp > 1)
                        amountUp = 1;

                    outRect.top = -(int) (floatingItemBounds.height() * amountUp);
                    outRect.bottom = (int) (floatingItemBounds.height() * amountUp);
                }

            }//Moving up the list
            // else if (totalMovment < 0)
            {
                if ((itemPos < selectedDragItemPos) && (view.getBottom() > floatMiddleY)) {
                    float amountDown = ((float) view.getBottom() - floatMiddleY) / (float) view.getHeight();
                    //  amountDown *= 0.5f;
                    if (amountDown > 1)
                        amountDown = 1;

                    outRect.top = (int) (floatingItemBounds.height() * amountDown);
                    outRect.bottom = -(int) (floatingItemBounds.height() * amountDown);
                }
            }
        }
    } else {
        outRect.top = 0;
        outRect.bottom = 0;
        //Make view visible incase invisible
        view.setVisibility(View.VISIBLE);
    }
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
/**
 * Find the new position by scanning through the items on
 * screen and finding the positional relationship.
 * This *seems* to work, another method would be to use
 * getItemOffsets, but I think that could miss items?..
 */
private int getNewPostion(RecyclerView rv) {
    int itemsOnScreen = rv.getLayoutManager().getChildCount();

    float floatMiddleY = floatingItemBounds.top + floatingItemBounds.height() / 2;

    int above = 0;
    int below = Integer.MAX_VALUE;
    for (int n = 0; n < itemsOnScreen; n++) //Scan though items on screen, however they may not
    {                                   // be in order!

        View view = rv.getLayoutManager().getChildAt(n);

        if (view.getVisibility() != View.VISIBLE)
            continue;

        int itemPos = rv.getChildPosition(view);

        if (itemPos == selectedDragItemPos) //Don't check against itself!
            continue;

        float viewMiddleY = view.getTop() + view.getHeight() / 2;
        if (floatMiddleY > viewMiddleY) //Is above this item
        {
            if (itemPos > above)
                above = itemPos;
        } else if (floatMiddleY <= viewMiddleY && itemPos < below) //Is below this item
        {
            below = itemPos;
        }
    }
    debugLog("above = " + above + " below = " + below);

    if (below != Integer.MAX_VALUE) {
        if (below < selectedDragItemPos) //Need to count itself
            below++;
        return below - 1;
    } else {
        if (above < selectedDragItemPos)
            above++;

        return above;
    }
}
 

import android.support.v7.widget.RecyclerView; //導入方法依賴的package包/類
@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
    debugLog("onInterceptTouchEvent");

    //if (e.getAction() == MotionEvent.ACTION_DOWN)
    {
        View itemView = rv.findChildViewUnder(e.getX(), e.getY());

        if (itemView == null)
            return false;

        boolean dragging = false;

        if ((dragHandleWidth > 0) && (e.getX() < dragHandleWidth)) {
            dragging = true;
        } else if (viewHandleId != -1) {
            //Find the handle in the list item
            View handleView = itemView.findViewById(viewHandleId);

            if (handleView == null) {
                String TAG = "DragSortRecycler";
                Log.e(TAG, "The view ID " + viewHandleId + " was not found in the RecycleView item");
                return false;
            }

            //View should be visible to drag
            if (handleView.getVisibility() != View.VISIBLE) {
                return false;
            }

            //We need to find the relative position of the handle to the parent view
            //Then we can work out if the touch is within the handle
            int[] parentItemPos = new int[2];
            itemView.getLocationInWindow(parentItemPos);

            int[] handlePos = new int[2];
            handleView.getLocationInWindow(handlePos);

            int xRel = handlePos[0] - parentItemPos[0];
            int yRel = handlePos[1] - parentItemPos[1];

            Rect touchBounds = new Rect(itemView.getLeft() + xRel, itemView.getTop() + yRel,
                    itemView.getLeft() + xRel + handleView.getWidth(),
                    itemView.getTop() + yRel + handleView.getHeight()
            );

            if (touchBounds.contains((int) e.getX(), (int) e.getY()))
                dragging = true;

            debugLog("parentItemPos = " + parentItemPos[0] + " " + parentItemPos[1]);
            debugLog("handlePos = " + handlePos[0] + " " + handlePos[1]);
        }


        if (dragging) {
            debugLog("Started Drag");

            setIsDragging(true);

            floatingItem = createFloatingBitmap(itemView);

            fingerAnchorY = (int) e.getY();
            fingerOffsetInViewY = fingerAnchorY - itemView.getTop();
            fingerY = fingerAnchorY;

            selectedDragItemPos = rv.getChildPosition(itemView);
            debugLog("selectedDragItemPos = " + selectedDragItemPos);

            return true;
        }
    }
    return false;
}