/// <summary>
/// 获取数据行的垂直位置
/// </summary>
/// <param name="p_index"></param>
/// <returns></returns>
internal override double GetRowVerPos(int p_index)
{
double height = 0;
if (_owner.IsVir)
{
// 虚拟行，等高
height = Math.Floor((double)p_index / _colCount) * _rowHeight;
if (_owner.MapRows != null)
{
// 等高有分组
int cnt = 0, iGrpRow = 0;
for (int i = 0; i < _owner.MapRows.Count; i++)
{
if (_owner.MapRows[i])
{
height += _owner.GroupRows[iGrpRow++].DesiredSize.Height;
}
else
{
cnt++;
}
if (cnt > p_index)
{
break;
}
}
}
}
else
{
// 真实行
if (_owner.MapRows == null)
{
// 无分组
for (int i = 0; i < p_index; i++)
{
// 行末尾项
bool isRowLast = ((i + 1) % _colCount == 0);
if (isRowLast)
{
height += _rowHeight;
}
}
}
else
{
// 有分组
int iDataRow = 0, iGrpRow = 0;
// 分组内的项目索引
int indexInGroup = 0;
LvRow lastRow = null;
for (int i = 0; i < _owner.MapRows.Count; i++)
{
if (_owner.MapRows[i])
{
if (lastRow != null)
{
// 上个分组最后未摆满一行
height += _rowHeight;
lastRow = null;
}
height += _owner.GroupRows[iGrpRow++].DesiredSize.Height;
}
else
{
bool isRowLast = ((indexInGroup + 1) % _colCount == 0);
if (isRowLast)
{
// 摆满一行
height += _rowHeight;
lastRow = null;
}
else
{
// 记录最后一项
lastRow = _dataRows[iDataRow];
}
iDataRow++;
indexInGroup++;
}
if (iDataRow >= p_index)
{
break;
}
}
}
}
if (_groupHeader != null)
{
height -= _groupHeader.DesiredSize.Height;
}
return(Math.Max(height, 0));
}
protected override void ArrangeGroupRealRows(Size p_finalSize)
{
int iGrpRow = 0, iDataRow = 0;
double totalHeight = 0;
GroupRow lastGroup = null;
bool firstVisible = true;
LvRow lastRow = null;
// 分组内的项目索引
int indexInGroup = 0;
for (int i = 0; i < _owner.MapRows.Count; i++)
{
if (_owner.MapRows[i])
{
// 布局分组
if (lastRow != null)
{
// 上个分组最后未摆满一行
totalHeight += _rowHeight;
lastRow = null;
}
var gr = _owner.GroupRows[iGrpRow++];
// 若未进入可视区
if (firstVisible)
{
// top为行的上侧和滚动栏上侧的距离，bottom为行的下侧距离
double top = totalHeight + _deltaY;
double bottom = top + gr.DesiredSize.Height;
// 可见区域：0 - _maxSize.Height
if ((top > 0 && top < _maxSize.Height) ||
(bottom > 0 && bottom < _maxSize.Height))
{
// 初次进入可见区，确定可见区顶端行所属分组
firstVisible = false;
lastGroup = _owner.GroupRows[iGrpRow - 1];
}
}
gr.Arrange(new Rect(0, totalHeight, p_finalSize.Width, gr.DesiredSize.Height));
totalHeight += gr.DesiredSize.Height;
indexInGroup = 0;
}
else
{
var row = _dataRows[iDataRow++];
// 若未进入可视区
if (firstVisible)
{
double top = totalHeight + _deltaY;
double bottom = top + row.DesiredSize.Height;
// 可见区域：0 - _maxSize.Height
if ((top > 0 && top < _maxSize.Height) ||
(bottom > 0 && bottom < _maxSize.Height))
{
// 初次进入可见区，确定可见区顶端行所属分组
firstVisible = false;
lastGroup = _owner.GroupRows[iGrpRow - 1];
}
}
bool isRowLast = ((indexInGroup + 1) % _colCount == 0);
row.Arrange(new Rect((indexInGroup % _colCount) * _itemWidth, totalHeight, isRowLast ? _itemWidth + 1 : _itemWidth, _rowHeight));
if (isRowLast)
{
// 摆满一行
totalHeight += _rowHeight;
lastRow = null;
}
else
{
// 记录最后一项
lastRow = row;
}
indexInGroup++;
}
}
// 分组导航头
if (_groupHeader != null)
{
if (!_isScrolling &&
_deltaY < _groupHeader.DesiredSize.Height &&
lastGroup != null)
{
// 离滚动栏顶部距离小于分组导航头高度时显示
// 分组导航头高度可能为0！
_groupHeader.SetCurrentGroup(lastGroup);
// -_deltaY确保始终在滚动栏顶部位置
_groupHeader.Arrange(new Rect(0, -_deltaY, p_finalSize.Width, _groupHeader.DesiredSize.Height));
}
else
{
// 第一行在滚动栏下侧太远时不显示分组导航头
_groupHeader.Arrange(_rcEmpty);
}
}
}
protected override void ArrangeGroupVirRows(Size p_finalSize)
{
// 整个面板不在滚动栏可视区时，布局到空区域
if (_deltaY >= _maxSize.Height || // 面板在滚动栏下方外部
_deltaY <= -p_finalSize.Height) // 面板在滚动栏上方外部
{
// 虚拟数据行
foreach (var elem in _dataRows)
{
elem.Arrange(_rcEmpty);
}
// 分组行
foreach (var grp in _owner.GroupRows)
{
grp.Arrange(_rcEmpty);
}
// 分组导航头
_groupHeader?.Arrange(_rcEmpty);
return;
}
int iAllRow = 0, iGrpRow = 0, iDataRow = 0;
double totalHeight = 0;
// 分组内的项目索引
int indexInGroup = 0;
LvRow lastRow = null;
//----------------------------------------------
// 面板可见，在滚动栏下方，按顺序布局所有行
//----------------------------------------------
if (_deltaY >= 0 && _deltaY < _maxSize.Height)
{
// 分组导航头
if (_groupHeader != null)
{
if (!_isScrolling && _deltaY < _groupHeader.DesiredSize.Height)
{
// 离滚动栏顶部距离小于分组导航头高度时显示
// 分组导航头高度可能为0！
_groupHeader.SetCurrentGroup(_owner.GroupRows[0]);
// -_deltaY确保始终在滚动栏顶部位置
_groupHeader.Arrange(new Rect(0, -_deltaY, p_finalSize.Width, _groupHeader.DesiredSize.Height));
}
else
{
// 离滚动栏顶部太远时不显示分组导航头
_groupHeader.Arrange(_rcEmpty);
}
}
for (int i = 0; i < _owner.MapRows.Count; i++)
{
if (_owner.MapRows[i])
{
// 布局分组行
if (lastRow != null)
{
// 上个分组最后未摆满一行
totalHeight += _rowHeight;
lastRow = null;
}
var gr = _owner.GroupRows[iGrpRow];
gr.Arrange(new Rect(0, totalHeight, p_finalSize.Width, gr.DesiredSize.Height));
totalHeight += gr.DesiredSize.Height;
iGrpRow++;
indexInGroup = 0;
}
else
{
// 布局数据行
var row = _dataRows[iDataRow];
// 行末尾项宽度加1为隐藏右边框
bool isRowLast = ((indexInGroup + 1) % _colCount == 0);
row.Arrange(new Rect((indexInGroup % _colCount) * _itemWidth, totalHeight, isRowLast ? _itemWidth + 1 : _itemWidth, _rowHeight));
row.SetViewRow(_owner.Rows[i - iGrpRow], true);
if (isRowLast)
{
// 摆满一行
totalHeight += _rowHeight;
lastRow = null;
}
else
{
// 记录最后一项
lastRow = row;
}
iDataRow++;
indexInGroup++;
// 虚拟行都已布局时退出
if (iDataRow >= _dataRows.Count)
{
break;
}
}
// 剩下行不可见，结束布局
if (_deltaY + totalHeight > _maxSize.Height)
{
break;
}
}
// 将剩余的虚拟行和分组行布局到空区域
if (iDataRow < _dataRows.Count)
{
for (int i = iDataRow; i < _dataRows.Count; i++)
{
_dataRows[i].Arrange(_rcEmpty);
}
}
if (iGrpRow < _owner.GroupRows.Count)
{
for (int i = iGrpRow; i < _owner.GroupRows.Count; i++)
{
_owner.GroupRows[i].Arrange(_rcEmpty);
}
}
return;
}
//----------------------------------------------
// _deltaY < 0 && _deltaY > -p_finalSize.Height
// 面板顶部超出滚动栏 并且 没有整个面板都超出，此时_deltaY为负数
//----------------------------------------------
// 避免所有行完全超出滚动栏顶部的情况
iAllRow = _owner.MapRows.Count;
GroupRow lastGroup = null;
// 布局顶部超出的分组、计算总高、数据行索引
for (int i = 0; i < _owner.MapRows.Count; i++)
{
if (_owner.MapRows[i])
{
// 分组行
// 布局上个分组
if (lastGroup != null)
{
lastGroup.Arrange(_rcEmpty);
}
lastGroup = _owner.GroupRows[iGrpRow];
double height = lastGroup.DesiredSize.Height;
if (totalHeight + height > -_deltaY)
{
// 进入可见区
iAllRow = i;
break;
}
iGrpRow++;
totalHeight += height;
indexInGroup = 0;
}
else
{
// 数据行
if (indexInGroup % _colCount == 0)
{
// 换行
if (totalHeight + _rowHeight > -_deltaY)
{
// 进入可见区
iAllRow = i;
break;
}
totalHeight += _rowHeight;
}
iDataRow++;
indexInGroup++;
}
}
// 可见数据行在所有虚拟行的索引
iDataRow = iDataRow % _pageItemCount;
// 分组导航头
if (_groupHeader != null)
{
if (!_isScrolling && iAllRow < _owner.MapRows.Count)
{
_groupHeader.SetCurrentGroup(lastGroup);
// -_deltaY确保始终在滚动栏顶部位置
_groupHeader.Arrange(new Rect(0, -_deltaY, p_finalSize.Width, _groupHeader.DesiredSize.Height));
}
else
{
// 所有数据行都在滚动栏上侧
_groupHeader.Arrange(_rcEmpty);
}
}
// 布局可视行
int iStart = iDataRow;
for (int i = iAllRow; i < _owner.MapRows.Count; i++)
{
if (_owner.MapRows[i])
{
// 布局分组
if (lastRow != null)
{
// 上个分组最后未摆满一行
totalHeight += _rowHeight;
lastRow = null;
}
var gr = _owner.GroupRows[iGrpRow];
gr.Arrange(new Rect(0, totalHeight, p_finalSize.Width, gr.DesiredSize.Height));
totalHeight += gr.DesiredSize.Height;
iGrpRow++;
indexInGroup = 0;
}
else
{
var row = _dataRows[iDataRow];
// 行末尾项宽度加1为隐藏右边框
bool isRowLast = ((indexInGroup + 1) % _colCount == 0);
row.Arrange(new Rect((indexInGroup % _colCount) * _itemWidth, totalHeight, isRowLast ? _itemWidth + 1 : _itemWidth, _rowHeight));
row.SetViewRow(_owner.Rows[i - iGrpRow], true);
if (isRowLast)
{
// 摆满一行
totalHeight += _rowHeight;
lastRow = null;
}
else
{
// 记录最后一项
lastRow = row;
}
iDataRow++;
indexInGroup++;
if (iDataRow >= _dataRows.Count)
{
iDataRow = 0;
}
if (iDataRow == iStart)
{
break;
}
}
// 剩下行不可见，结束布局
if (_deltaY + totalHeight > _maxSize.Height)
{
break;
}
}
// 无法确定剩余的虚拟行，上次布局在不可见区域不需再布局！
// 将剩余分组布局到空区域
if (iGrpRow < _owner.GroupRows.Count)
{
for (int i = iGrpRow; i < _owner.GroupRows.Count; i++)
{
_owner.GroupRows[i].Arrange(_rcEmpty);
}
}
}
