android.support.v7.widget.StaggeredGridLayoutManager#getSpanCount ( )源码实例Demo

下面列出了android.support.v7.widget.StaggeredGridLayoutManager#getSpanCount ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。

源代码1 项目： ItemDecorationDemo 文件： StaggeredSpaceDecoration.java

@Override
public void getItemOffsets(@NonNull Rect outRect, @NonNull View view,
                           @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
    RecyclerView.LayoutManager originalManager = parent.getLayoutManager();
    if (originalManager == null || !(originalManager instanceof StaggeredGridLayoutManager)) {
        return;
    }
    StaggeredGridLayoutManager manager = (StaggeredGridLayoutManager) originalManager;
    mSpanCount = manager.getSpanCount();
    mItemCount = parent.getAdapter().getItemCount();
    if (manager.getOrientation() == StaggeredGridLayoutManager.VERTICAL) {
        handleVertical(outRect, view, parent);
    } else {
        handleHorizontal(outRect, view, parent);
    }
}

源代码2 项目： ExRecyclerView 文件： OnRecyclerViewScrollListener.java

/**
 * 计算第一个元素的位置
 */
private int calculateFirstVisibleItemPos(RecyclerView.LayoutManager layoutManager, int firstVisibleItemPosition) {
    switch (mLayoutManagerType) {
        case LINEAR:
            mLastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            firstVisibleItemPosition = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
            break;
        case GRID:
            mLastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            firstVisibleItemPosition = ((GridLayoutManager) layoutManager).findFirstVisibleItemPosition();
            break;
        case STAGGERED_GRID:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (mLastPositions == null) {
                mLastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            mLastPositions = staggeredGridLayoutManager.findLastVisibleItemPositions(mLastPositions);
            mLastVisibleItemPosition = findMax(mLastPositions);
            staggeredGridLayoutManager.findFirstCompletelyVisibleItemPositions(mLastPositions);
            firstVisibleItemPosition = findMax(mLastPositions);
            break;
    }
    return firstVisibleItemPosition;
}

源代码3 项目： Android-RecyclerViewHelper 文件： RecyclerViewScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);
    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
    if (layoutManager instanceof GridLayoutManager) {
        lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
    } else if (layoutManager instanceof LinearLayoutManager) {
        lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
    } else if (layoutManager instanceof StaggeredGridLayoutManager) {
        StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
        if (lastPositions == null) {
            lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
        }
        staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
        lastVisibleItemPosition = findMax(lastPositions);
    } else {
        throw new RuntimeException("Unsupported LayoutManager used. " +
                "Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
    }
}

源代码4 项目： EasyRefreshLayout 文件： EasyRefreshLayout.java

/**
 * 最后一个的位置
 */
private int getLastVisiBleItem() {
    RecyclerView.LayoutManager layoutManager = mRecyclerView.getLayoutManager();
    int lastVisibleItemPosition = -1;

    int layoutManagerType = 0;
    if (layoutManager instanceof GridLayoutManager) {
        layoutManagerType = 1;
    } else if (layoutManager instanceof LinearLayoutManager) {
        layoutManagerType = 0;
    } else if (layoutManager instanceof StaggeredGridLayoutManager) {
        layoutManagerType = 2;
    } else {
        throw new RuntimeException(
                "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
    }

    switch (layoutManagerType) {
        case 0:
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case 1:
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case 2:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            int[] lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            break;
    }
    return lastVisibleItemPosition;
}

源代码5 项目： HeaderAndFooterRecyclerView 文件： EndlessRecyclerOnScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);

    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();

    if (layoutManagerType == null) {
        if (layoutManager instanceof GridLayoutManager) {
            layoutManagerType = LayoutManagerType.GridLayout;
        } else if (layoutManager instanceof LinearLayoutManager) {
            layoutManagerType = LayoutManagerType.LinearLayout;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            layoutManagerType = LayoutManagerType.StaggeredGridLayout;
        } else {
            throw new RuntimeException(
                    "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
        }
    }

    switch (layoutManagerType) {
        case LinearLayout:
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GridLayout:
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case StaggeredGridLayout:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            break;
    }
}

源代码6 项目： Pas 文件： DRecyclerViewScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);

    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();

    if (layoutManagerType == null) {
        if (layoutManager instanceof LinearLayoutManager) {
            layoutManagerType = LayoutManagerType.LinearLayout;
        } else if (layoutManager instanceof GridLayoutManager) {
            layoutManagerType = LayoutManagerType.GridLayout;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            layoutManagerType = LayoutManagerType.StaggeredGridLayout;
        } else {
            throw new RuntimeException(
                    "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
        }
    }

    switch (layoutManagerType) {
        case LinearLayout:
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GridLayout:
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case StaggeredGridLayout:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            break;
    }


}

源代码7 项目： GankGirl 文件： RecyclerViewOnScroll.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);

    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();

    if (layoutManagerType == null) {
        if (layoutManager instanceof LinearLayoutManager) {
            layoutManagerType = LayoutManagerType.LinearLayout;
        } else if (layoutManager instanceof GridLayoutManager) {
            layoutManagerType = LayoutManagerType.GridLayout;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            layoutManagerType = LayoutManagerType.StaggeredGridLayout;
        } else {
            throw new RuntimeException(
                    "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
        }
    }

    switch (layoutManagerType) {
        case LinearLayout:
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GridLayout:
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case StaggeredGridLayout:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            break;
    }
}

源代码8 项目： HeaderFooterRecyclerView 文件： EndlessRecyclerOnScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);

    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();

    if (layoutManagerType == null) {
        if (layoutManager instanceof LinearLayoutManager) {
            layoutManagerType = LayoutManagerType.LinearLayout;
        } else if (layoutManager instanceof GridLayoutManager) {
            layoutManagerType = LayoutManagerType.GridLayout;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            layoutManagerType = LayoutManagerType.StaggeredGridLayout;
        } else {
            throw new RuntimeException(
                    "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
        }
    }

    switch (layoutManagerType) {
        case LinearLayout:
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GridLayout:
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case StaggeredGridLayout:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            break;
    }
}

源代码9 项目： RecyclerViewDemo 文件： BasePullUpRecyclerAdapter.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);
    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
    if (layoutManager instanceof LinearLayoutManager) {
        layoutManagerType = LINEAR;
    } else if (layoutManager instanceof GridLayoutManager) {
        layoutManagerType = GRID;
    } else if (layoutManager instanceof StaggeredGridLayoutManager) {
        layoutManagerType = STAGGERED_GRID;
    } else {
        throw new RuntimeException(
                "Unsupported LayoutManager used. Valid ones are " +
                        "LinearLayoutManager, GridLayoutManager and " +
                        "StaggeredGridLayoutManager");
    }

    switch (layoutManagerType) {
        case LINEAR:
            lastVisibleItem = ((LinearLayoutManager) layoutManager)
                    .findLastVisibleItemPosition();
            break;
        case GRID:
            lastVisibleItem = ((GridLayoutManager) layoutManager)
                    .findLastVisibleItemPosition();
            break;
        case STAGGERED_GRID:
            StaggeredGridLayoutManager staggeredGridLayoutManager
                    = (StaggeredGridLayoutManager) layoutManager;
            lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItem = findMax(lastPositions);
            break;
    }
}

源代码10 项目： CoreModule 文件： BasePullUpRecyclerAdapter.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
    super.onScrolled(recyclerView, dx, dy);
    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
    if (layoutManager instanceof LinearLayoutManager) {
        layoutManagerType = LINEAR;
    } else if (layoutManager instanceof GridLayoutManager) {
        layoutManagerType = GRID;
    } else if (layoutManager instanceof StaggeredGridLayoutManager) {
        layoutManagerType = STAGGERED_GRID;
    } else {
        throw new RuntimeException(
                "Unsupported LayoutManager used. Valid ones are " +
                        "LinearLayoutManager, GridLayoutManager and " +
                        "StaggeredGridLayoutManager");
    }

    switch (layoutManagerType) {
        case LINEAR:
            lastVisibleItem = ((LinearLayoutManager) layoutManager)
                    .findLastVisibleItemPosition();
            break;
        case GRID:
            lastVisibleItem = ((GridLayoutManager) layoutManager)
                    .findLastVisibleItemPosition();
            break;
        case STAGGERED_GRID:
            StaggeredGridLayoutManager staggeredGridLayoutManager
                    = (StaggeredGridLayoutManager) layoutManager;
            lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItem = findMax(lastPositions);
            break;
    }
}

源代码11 项目： AndroidBase 文件： FamiliarDefaultItemDecoration.java

private void initLayoutManagerType() {
    this.mLayoutManagerType = mRecyclerViewListener.getCurLayoutManagerType();
    RecyclerView.LayoutManager layoutManager = mRecyclerViewListener.getCurLayoutManager();
    switch (mLayoutManagerType) {
        case FamiliarRecyclerView.LAYOUT_MANAGER_TYPE_LINEAR:
            LinearLayoutManager curLinearLayoutManager = (LinearLayoutManager)layoutManager;
            if (curLinearLayoutManager.getOrientation() == LinearLayoutManager.HORIZONTAL) {
                mOrientation = OrientationHelper.HORIZONTAL;
            } else {
                mOrientation = OrientationHelper.VERTICAL;
            }
            break;
        case FamiliarRecyclerView.LAYOUT_MANAGER_TYPE_GRID:
            GridLayoutManager curGridLayoutManager = (GridLayoutManager)layoutManager;
            mGridSpanCount = curGridLayoutManager.getSpanCount();
            if (curGridLayoutManager.getOrientation() == LinearLayoutManager.HORIZONTAL) {
                mOrientation = OrientationHelper.HORIZONTAL;
            } else {
                mOrientation = OrientationHelper.VERTICAL;
            }
            break;
        case FamiliarRecyclerView.LAYOUT_MANAGER_TYPE_STAGGERED_GRID:
            StaggeredGridLayoutManager curStaggeredGridLayoutManager = (StaggeredGridLayoutManager)layoutManager;
            mGridSpanCount = curStaggeredGridLayoutManager.getSpanCount();
            if (curStaggeredGridLayoutManager.getOrientation() == LinearLayoutManager.HORIZONTAL) {
                mOrientation = OrientationHelper.HORIZONTAL;
            } else {
                mOrientation = OrientationHelper.VERTICAL;
            }
            break;
        default:
            this.mLayoutManagerType = FamiliarRecyclerView.LAYOUT_MANAGER_TYPE_LINEAR;
    }

    initDivisible();
}

源代码12 项目： weex 文件： WXRecyclerViewOnScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
  super.onScrolled(recyclerView, dx, dy);
  RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
  //  int lastVisibleItemPosition = -1;
  if (layoutManagerType == null) {
    if (layoutManager instanceof LinearLayoutManager) {
      layoutManagerType = LAYOUT_MANAGER_TYPE.LINEAR;
    } else if (layoutManager instanceof GridLayoutManager) {
      layoutManagerType = LAYOUT_MANAGER_TYPE.GRID;
    } else if (layoutManager instanceof StaggeredGridLayoutManager) {
      layoutManagerType = LAYOUT_MANAGER_TYPE.STAGGERED_GRID;
    } else {
      throw new RuntimeException(
          "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
    }
  }

  switch (layoutManagerType) {
    case LINEAR:
      lastVisibleItemPosition = ((LinearLayoutManager) layoutManager)
          .findLastVisibleItemPosition();
      listener.get().notifyAppearStateChange(((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition()
          ,lastVisibleItemPosition
          ,dx
          ,dy);
      break;
    case GRID:
      lastVisibleItemPosition = ((GridLayoutManager) layoutManager)
          .findLastVisibleItemPosition();
      break;
    case STAGGERED_GRID:
      StaggeredGridLayoutManager staggeredGridLayoutManager
          = (StaggeredGridLayoutManager) layoutManager;
      if (lastPositions == null) {
        lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
      }
      staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
      lastVisibleItemPosition = findMax(lastPositions);
      break;
  }
}

源代码13 项目： AndroidBase 文件： FamiliarRecyclerView.java

public int getLastVisiblePosition() {
    LayoutManager layoutManager = getLayoutManager();
    if (null == layoutManager)
        return -1;

    int curItemCount = (null != mReqAdapter ? mReqAdapter.getItemCount() - 1 : 0);
    int ret = -1;

    switch (mLayoutManagerType) {
        case LAYOUT_MANAGER_TYPE_LINEAR:
            ret = ((LinearLayoutManager) layoutManager).findLastCompletelyVisibleItemPosition() - getHeaderViewsCount();
            if (ret > curItemCount) {
                ret -= getFooterViewsCount();
            }
            break;
        case LAYOUT_MANAGER_TYPE_GRID:
            ret = ((GridLayoutManager) layoutManager).findLastCompletelyVisibleItemPosition() - getHeaderViewsCount();
            if (ret > curItemCount) {
                ret -= getFooterViewsCount();
            }
            break;
        case LAYOUT_MANAGER_TYPE_STAGGERED_GRID:
            StaggeredGridLayoutManager tempStaggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            int[] lastVisibleItemPositions = new int[tempStaggeredGridLayoutManager.getSpanCount()];
            tempStaggeredGridLayoutManager.findLastCompletelyVisibleItemPositions(lastVisibleItemPositions);
            if (lastVisibleItemPositions.length > 0) {
                int maxPos = lastVisibleItemPositions[0];
                for (int curPos : lastVisibleItemPositions) {
                    if (curPos > maxPos)
                        maxPos = curPos;
                }
                ret = maxPos - getHeaderViewsCount();
                if (ret > curItemCount) {
                    ret -= getFooterViewsCount();
                }
            }
            break;
    }

    return ret < 0 ? (null != mReqAdapter ? mReqAdapter.getItemCount() - 1 : 0) : ret;
}

源代码14 项目： scallop 文件： EndlessRecyclerViewScrollListener.java

public EndlessRecyclerViewScrollListener(StaggeredGridLayoutManager layoutManager) {
    this.mLayoutManager = layoutManager;
    visibleThreshold = visibleThreshold * layoutManager.getSpanCount();
}

源代码15 项目： YCShopDetailLayout 文件： VerticalRecyclerView.java

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
    RecyclerView.LayoutManager layoutManager = getLayoutManager();
    if (layoutManager != null) {
        if (layoutManager instanceof GridLayoutManager) {
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            firstVisibleItemPosition = ((GridLayoutManager) layoutManager).findFirstVisibleItemPosition();
        } else if (layoutManager instanceof LinearLayoutManager) {
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            firstVisibleItemPosition = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
                firstPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            staggeredGridLayoutManager.findFirstVisibleItemPositions(firstPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            firstVisibleItemPosition = findMin(firstPositions);
        }
    } else {
        throw new RuntimeException("Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
    }

    switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN:
            downX = ev.getX();
            downY = ev.getY();
            //如果滑动到了最底部，就允许继续向上滑动加载下一页，否者不允许
            getParent().requestDisallowInterceptTouchEvent(true);
            break;
        case MotionEvent.ACTION_MOVE:
            float dx = ev.getX() - downX;
            float dy = ev.getY() - downY;
            boolean allowParentTouchEvent;
            if (Math.abs(dy) > Math.abs(dx)) {
                if (dy > 0) {
                    //位于顶部时下拉，让父View消费事件
                    allowParentTouchEvent = isTop = firstVisibleItemPosition == 0 && getChildAt(0).getTop() >= 0;
                } else {
                    //位于底部时上拉，让父View消费事件
                    int visibleItemCount = layoutManager.getChildCount();
                    int totalItemCount = layoutManager.getItemCount();
                    allowParentTouchEvent = isBottom = visibleItemCount > 0 && (lastVisibleItemPosition) >= totalItemCount - 1 && getChildAt(getChildCount() - 1).getBottom() <= getHeight();
                }
            } else {
                //水平方向滑动
                allowParentTouchEvent = true;
            }
            getParent().requestDisallowInterceptTouchEvent(!allowParentTouchEvent);
            break;
        default:
            break;
    }
    return super.dispatchTouchEvent(ev);

}

源代码16 项目： ucar-weex-core 文件： WXRecyclerViewOnScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
  super.onScrolled(recyclerView, dx, dy);
  RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
  if(listener == null){
    return;
  }
  IOnLoadMoreListener iOnLoadMoreListener = listener.get();

  if(iOnLoadMoreListener!=null) {

    iOnLoadMoreListener.onBeforeScroll(dx, dy);

    if (layoutManager instanceof LinearLayoutManager) {
      layoutManagerType = LAYOUT_MANAGER_TYPE.LINEAR;
      LinearLayoutManager linearLayoutManager = (LinearLayoutManager) layoutManager;
      mLastVisibleItemPosition = linearLayoutManager.findLastVisibleItemPosition();
      int firstVisible = linearLayoutManager.findFirstVisibleItemPosition();
      iOnLoadMoreListener.notifyAppearStateChange(firstVisible
          , mLastVisibleItemPosition
          , dx
          , dy);
    } else if (layoutManager instanceof GridLayoutManager) {
      layoutManagerType = LAYOUT_MANAGER_TYPE.GRID;
      GridLayoutManager gridLayoutManager = (GridLayoutManager) layoutManager;
      mLastVisibleItemPosition = gridLayoutManager.findLastVisibleItemPosition();
      iOnLoadMoreListener.notifyAppearStateChange(gridLayoutManager.findFirstVisibleItemPosition()
          , mLastVisibleItemPosition
          , dx
          , dy);

    } else if (layoutManager instanceof StaggeredGridLayoutManager) {
      layoutManagerType = LAYOUT_MANAGER_TYPE.STAGGERED_GRID;
      StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
      int newSpanCount = staggeredGridLayoutManager.getSpanCount();
      if (mLastPositions == null || newSpanCount != mLastPositions.length) {
        mLastPositions = new int[newSpanCount];
      }
      if (mFirstPositions == null || newSpanCount != mFirstPositions.length) {
        mFirstPositions = new int[newSpanCount];
      }
      //avoid crash of support-v7 original bug
      try{
        staggeredGridLayoutManager.findFirstVisibleItemPositions(mFirstPositions);
        mFirstVisibleItemPosition = findMin(mFirstPositions);
        staggeredGridLayoutManager.findLastVisibleItemPositions(mLastPositions);
        mLastVisibleItemPosition = findMax(mLastPositions);
        iOnLoadMoreListener.notifyAppearStateChange(
            mFirstVisibleItemPosition
            , mLastVisibleItemPosition
            , dx
            , dy);

      }catch(Exception e){
        e.printStackTrace();
        WXLogUtils.e(e.toString());
      }

    } else {
      throw new RuntimeException(
          "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
    }
  }
}

源代码17 项目： Social 文件： RecyclerViewScrollListener.java

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {

    Log.d(TAG, "onScrolled: dy = " + dy);

    /**
     * 获取布局参数
     */
    RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();

    //如果为null，第一次运行，确定布局类型
    if (mLayoutManagerType == null) {
        if (layoutManager instanceof LinearLayoutManager) {
            mLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT;
        } else if (layoutManager instanceof GridLayoutManager) {
            mLayoutManagerType = LayoutManagerType.GRID_LAYOUT;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            mLayoutManagerType = LayoutManagerType.STAGGERED_GRID_LAYOUT;
        } else {
            throw new RuntimeException("LayoutManager should be LinearLayoutManager,GridLayoutManager,StaggeredGridLayoutManager");
        }
    }

    //对于不太能够的布局参数，不同的方法获取到当前显示的最后一个条目数
    switch (mLayoutManagerType) {
        case LINEAR_LAYOUT:
            mLastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GRID_LAYOUT:
            mLastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            int firstItemPosition = ((GridLayoutManager) layoutManager).findFirstVisibleItemPosition();
            Log.d(TAG, "onScrolled: firstPosition = " + firstItemPosition);
            break;
        case STAGGERED_GRID_LAYOUT:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (mLastPostions == null) {
                mLastPostions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(mLastPostions);
            mLastVisibleItemPosition = findMax(mLastPostions);
            break;
        default:
            break;
    }

}

源代码18 项目： LRecyclerView 文件： LRecyclerView.java

@Override
public void onScrolled(int dx, int dy) {
    super.onScrolled(dx, dy);

    int firstVisibleItemPosition = 0;
    RecyclerView.LayoutManager layoutManager = getLayoutManager();

    if (layoutManagerType == null) {
        if (layoutManager instanceof LinearLayoutManager) {
            layoutManagerType = LayoutManagerType.LinearLayout;
        } else if (layoutManager instanceof GridLayoutManager) {
            layoutManagerType = LayoutManagerType.GridLayout;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            layoutManagerType = LayoutManagerType.StaggeredGridLayout;
        } else {
            throw new RuntimeException(
                    "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
        }
    }

    switch (layoutManagerType) {
        case LinearLayout:
            firstVisibleItemPosition = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GridLayout:
            firstVisibleItemPosition = ((GridLayoutManager) layoutManager).findFirstVisibleItemPosition();
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case StaggeredGridLayout:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            staggeredGridLayoutManager.findFirstCompletelyVisibleItemPositions(lastPositions);
            firstVisibleItemPosition = findMax(lastPositions);
            break;
        default:
            break;
    }

    // 根据类型来计算出第一个可见的item的位置，由此判断是否触发到底部的监听器
    // 计算并判断当前是向上滑动还是向下滑动
    calculateScrollUpOrDown(firstVisibleItemPosition, dy);
    // 移动距离超过一定的范围，我们监听就没有啥实际的意义了
    mScrolledXDistance += dx;
    mScrolledYDistance += dy;
    mScrolledXDistance = (mScrolledXDistance < 0) ? 0 : mScrolledXDistance;
    mScrolledYDistance = (mScrolledYDistance < 0) ? 0 : mScrolledYDistance;
    if (mIsScrollDown && (dy == 0)) {
        mScrolledYDistance = 0;
    }
    //Be careful in here
    if (null != mLScrollListener) {
        mLScrollListener.onScrolled(mScrolledXDistance, mScrolledYDistance);
    }

    if (mLoadMoreListener != null && mLoadMoreEnabled) {
        int visibleItemCount = layoutManager.getChildCount();
        int totalItemCount = layoutManager.getItemCount();
        if (visibleItemCount > 0
                && lastVisibleItemPosition >= totalItemCount - 1
                && (isCritical ? totalItemCount >= visibleItemCount : totalItemCount > visibleItemCount)
                && !isNoMore
                && !mRefreshing) {

            mFootView.setVisibility(View.VISIBLE);
            if (!mLoadingData) {
                mLoadingData = true;
                mLoadMoreFooter.onLoading();
                mLoadMoreListener.onLoadMore();
            }

        }

    }
    if (isOnTop() && dy > 0 && mRefreshHeader.getType() == IRefreshHeader.TYPE_HEADER_MATERIAL && !mRefreshing && (appbarState
        == AppBarStateChangeListener.State.EXPANDED)) {
        mRefreshHeader.onMove(dy, mScrolledYDistance);
    }
}

源代码19 项目： LRecyclerView 文件： LuRecyclerView.java

@Override
public void onScrolled(int dx, int dy) {
    super.onScrolled(dx, dy);

    int firstVisibleItemPosition = 0;
    RecyclerView.LayoutManager layoutManager = getLayoutManager();

    if (layoutManagerType == null) {
        if (layoutManager instanceof LinearLayoutManager) {
            layoutManagerType = LayoutManagerType.LinearLayout;
        } else if (layoutManager instanceof GridLayoutManager) {
            layoutManagerType = LayoutManagerType.GridLayout;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            layoutManagerType = LayoutManagerType.StaggeredGridLayout;
        } else {
            throw new RuntimeException(
                    "Unsupported LayoutManager used. Valid ones are LinearLayoutManager, GridLayoutManager and StaggeredGridLayoutManager");
        }
    }

    switch (layoutManagerType) {
        case LinearLayout:
            firstVisibleItemPosition = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
            lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case GridLayout:
            firstVisibleItemPosition = ((GridLayoutManager) layoutManager).findFirstVisibleItemPosition();
            lastVisibleItemPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            break;
        case StaggeredGridLayout:
            StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
            if (lastPositions == null) {
                lastPositions = new int[staggeredGridLayoutManager.getSpanCount()];
            }
            staggeredGridLayoutManager.findLastVisibleItemPositions(lastPositions);
            lastVisibleItemPosition = findMax(lastPositions);
            staggeredGridLayoutManager.findFirstCompletelyVisibleItemPositions(lastPositions);
            firstVisibleItemPosition = findMax(lastPositions);
            break;
        default:
            break;
    }

    // 根据类型来计算出第一个可见的item的位置，由此判断是否触发到底部的监听器
    // 计算并判断当前是向上滑动还是向下滑动
    calculateScrollUpOrDown(firstVisibleItemPosition, dy);
    // 移动距离超过一定的范围，我们监听就没有啥实际的意义了
    mScrolledXDistance += dx;
    mScrolledYDistance += dy;
    mScrolledXDistance = (mScrolledXDistance < 0) ? 0 : mScrolledXDistance;
    mScrolledYDistance = (mScrolledYDistance < 0) ? 0 : mScrolledYDistance;
    if (mIsScrollDown && (dy == 0)) {
        mScrolledYDistance = 0;
    }
    //Be careful in here
    if (null != mLScrollListener) {
        mLScrollListener.onScrolled(mScrolledXDistance, mScrolledYDistance);
    }

    //如果想要滑动到底部自动加载更多，mIsManualLoadMore必须为false
    if (mIsManualLoadMore) {
        if (!isNoMore) {
            Log.e("lzx","onScrooo set visible");
            mLoadingData = true;
            mLoadMoreFooter.setOnClickLoadMoreListener(mLoadMoreListener);
        }

    } else {
        if (mLoadMoreListener != null && mLoadMoreEnabled) {
            int visibleItemCount = layoutManager.getChildCount();
            int totalItemCount = layoutManager.getItemCount();
            if (visibleItemCount > 0
                    && lastVisibleItemPosition >= totalItemCount - 1
                    && (isCritical ? totalItemCount >= visibleItemCount : totalItemCount > visibleItemCount)
                    && !isNoMore
                    && !mRefreshing) {

                mFootView.setVisibility(View.VISIBLE);
                if (!mLoadingData) {
                    mLoadingData = true;
                    mLoadMoreFooter.onLoading();
                    mLoadMoreListener.onLoadMore();
                }

            }

        }
    }

}

源代码20 项目： droidddle 文件： QuickReturnRecyclerView.java

public void checkLoadingMore() {
    boolean firstVisible = false;

    LayoutManager manager = getLayoutManager();

    int visibleItemCount = manager.getChildCount();
    int totalItemCount = manager.getItemCount();
    int firstVisibleItems = 0;
    if (manager instanceof LinearLayoutManager) {
        firstVisibleItems = ((LinearLayoutManager) manager).findFirstVisibleItemPosition();
    } else if (manager instanceof GridLayoutManager) {
        firstVisibleItems = ((GridLayoutManager) manager).findFirstVisibleItemPosition();
    } else if (manager instanceof StaggeredGridLayoutManager) {
        StaggeredGridLayoutManager sg = ((StaggeredGridLayoutManager) manager);
        int[] items = new int[sg.getSpanCount()];
        items = ((StaggeredGridLayoutManager) manager).findFirstVisibleItemPositions(items);
        firstVisibleItems = items[0];
    }

    //        boolean topOfFirstItemVisible = manager.getChildAt(0).getTop() >= mFirstTop;
    // enabling or disabling the refresh layout
    if (firstVisibleItems == 0) {
        View child = manager.getChildAt(0);
        if (child != null) {
            LayoutParams lp = (LayoutParams) child.getLayoutParams();
            firstVisible = manager.getChildAt(0).getTop() >= (getPaddingTop() + lp.topMargin);
        }
    }
    //        firstVisible = firstVisibleItems == 0 && topOfFirstItemVisible;

    mMoreListener.isFirstItemFullVisible(firstVisible);
    if (!mIsLoadingMore && mHasMoreData) {
        if ((visibleItemCount + firstVisibleItems) >= totalItemCount - 1) {
            if (!Utils.hasInternet(getContext())) {
                return;
            }
            mIsLoadingMore = true;
            mMoreListener.onLoadingMore();
        }
    }
}

方法所在类

android.support.v7.widget.StaggeredGridLayoutManager