/// <summary>
/// 绘制 <see cref="TreeList"/> 的列头。
/// </summary>
/// <param name="e"></param>
public virtual void DrawColumnHeader(TreeListColumnRenderEventArgs e)
{
//排序箭头的绘制区
var sortArrayRect = GetColumnHeaderSortArrayBound(e.Column, e.Bounds);
//图标绘制区
var image = e.Column?.GetImage();
var imageRect = image == null ? Rectangle.Empty : GetColumnHeaderImageRect(image, e.Column.ImageAlign, e.Bounds, sortArrayRect.Width);
//文本绘制区
var textBound = e.Column == null ? Rectangle.Empty : GetColumnHeaderTextRect(e.Bounds, sortArrayRect.Width, imageRect.Width, e.Column.ImageAlign);
DrawColumnHeaderBackground(e.Graphics, e.Bounds, e.DrawState);
if (!sortArrayRect.IsEmpty && sortArrayRect.Left > e.Bounds.Left)
{
var order = e.Column.TreeList.GetSortOrder(e.Column);
DrawColumnSortArray(e.Graphics, sortArrayRect, order);
}
if (!imageRect.IsEmpty)
{
e.Graphics.DrawImage(image, imageRect);
}
if (!textBound.IsEmpty)
{
DrawColumnHeaderText(e.Graphics, e.Column, textBound);
}
}
/// <summary>
/// 绘制行号列头。
/// </summary>
/// <param name="e"></param>
public virtual void DrawRowNumberColumn(TreeListColumnRenderEventArgs e)
{
DrawColumnHeaderBackground(e.Graphics, e.Bounds, DrawState.Normal);
}
/// <summary>
/// 处理当前鼠标经过的对象。
/// </summary>
/// <param name="info"></param>
/// <param name="drawState"></param>
private void ProcessHitTestInfo(TreeListHitTestInfo info, DrawState drawState)
{
if (info.Bounds.IsEmpty)
{
return;
}
switch (info.HitTestType)
{
case TreeListHitTestType.Column:
var column = (TreeListColumn)info.Element;
using (var graphics = CreateGraphics())
{
var drawArgs = new TreeListColumnRenderEventArgs(column, graphics, info.Bounds)
{
DrawState = drawState
};
graphics.KeepClip(_bound.ColumnBound, () => Renderer.DrawColumnHeader(drawArgs));
}
break;
case TreeListHitTestType.ColumnSize:
Cursor = Cursors.VSplit;
break;
case TreeListHitTestType.Cell:
if (info.Owner != null)
{
ProcessHitTestInfo(info.Owner, drawState);
}
var cell = (TreeListCell)info.Element;
var rect = GetCellTextRectangle(cell, info.Bounds);
ShowToolTip(cell, rect);
break;
case TreeListHitTestType.Item:
if (HandCursor)
{
Cursor = Cursors.Hand;
}
if (drawState == DrawState.Pressed || !HotTracking)
{
return;
}
var vitem = (VirtualTreeListItem)info.Element;
var item = (TreeListItem)vitem.Item;
if (item.Selected)
{
return;
}
using (var graphics = CreateGraphics())
{
var drawArgs = new TreeListItemRenderEventArgs(item, graphics, info.Bounds)
{
DrawState = drawState,
Alternate = vitem.Index % 2 != 0
};
DrawItem(drawArgs);
}
break;
}
}
