/// <summary>
/// Makes render object representing a grid cell. That render object
/// may be inserted into the corresponding RenderTable's cell, or
/// for tree grids, into a RenderArea that combines the cell with tree glyphs.
/// </summary>
/// <param name="row">Grid row index.</param>
/// <param name="col">Grid column index.</param>
/// <param name="cellStyle">Cell style. May be modified by owner-drawn cells.</param>
/// <param name="text">The cell text.</param>
/// <returns>The render object representing the cell.
/// The type of object varies depending on the cell's content - it can be
/// a RenderText, a RenderImage, or a RenderArea containing both.
/// </returns>
private RenderObject MakeCellRO(int row, int col, ref CellStyle cellStyle, out string text)
{
Image image;
CheckEnum chk;
text = _grid.GetDataDisplay(row, col, out image, out chk);
// special treatment of bool columns - suppress text if a checkbox is drawn:
if (cellStyle.DataType == typeof(bool) && chk != CheckEnum.None)
{
text = null;
}
// handle owner-drawn cells:
if (_grid.DrawMode == DrawModeEnum.OwnerDraw && _grid2 != null)
{
// note: the next call may modify cell's style, text and image while returning null.
RenderObject ro = _grid2.MakeOwnerDrawCellRO(row, col, ref cellStyle, ref text, ref image);
if (ro != null)
{
return(ro);
}
// else process as regular (non-ownerdraw) cell; taking into consideration
// the possibly modified cell style, text and image.
}
bool overlay = false;
bool hasImage = image != null || chk != CheckEnum.None;
switch (cellStyle.Display)
{
case DisplayEnum.ImageOnly:
text = null;
break;
case DisplayEnum.None:
text = null;
hasImage = false;
break;
case DisplayEnum.Overlay:
overlay = true;
break;
case DisplayEnum.Stack:
break;
case DisplayEnum.TextOnly:
hasImage = false;
break;
default:
Debug.Assert(false);
break;
}
if (cellStyle.ImageAlign == ImageAlignEnum.Hide)
{
hasImage = false;
}
if (string.IsNullOrEmpty(text) && !hasImage)
{
return(null);
}
else if (!hasImage)
{
return(MakeTextRO(text, null));
}
else if (string.IsNullOrEmpty(text))
{
return(MakeImageRO(image, chk, null));
}
else
{
RenderObject rimg = MakeImageRO(image, chk, "img");
RenderObject rtxt = MakeTextRO(text, "txt");
ImageOn ion = AlignImage(rimg, cellStyle, overlay);
AlignText(rtxt, GetTextAlign(cellStyle, cellStyle.DataType, text), ion);
RenderArea ra = new RenderArea();
ra.Stacking = StackingRulesEnum.BlockLeftToRight;
ra.Children.Add(rimg);
ra.Children.Add(rtxt);
if (ion == ImageOn.Left || ion == ImageOn.Right)
{
ra.Width = "img.width + txt.width";
}
else if (ion == ImageOn.Top || ion == ImageOn.Bottom)
{
ra.Height = "img.height + txt.height";
}
else
{
ra.Width = Unit.Auto;
ra.Height = Unit.Auto;
}
return(ra);
}
}
/// <summary>
/// Used to position text within the cell relative to image.
/// This method assumes that the cell (represented by a RenderArea) contains
/// both image and text, and that the image (RenderImage) is the first child
/// within the render area (referenced by "prev" in position strings).
/// </summary>
/// <param name="rtxt"></param>
/// <param name="ta"></param>
/// <param name="ion"></param>
private void AlignText(RenderObject rtxt, TextAlignEnum ta, ImageOn ion)
{
switch (ta)
{
case TextAlignEnum.LeftTop:
rtxt.X = ion == ImageOn.Left ? "prev.right" : "0";
rtxt.Y = ion == ImageOn.Top ? "prev.bottom" : "0";
break;
case TextAlignEnum.LeftCenter:
rtxt.X = ion == ImageOn.Left ? "prev.right" : "0";
rtxt.Y = ion == ImageOn.Top ? "prev.bottom + (parent.height - prev.height - height) / 2" :
(ion == ImageOn.Bottom ? "(parent.height - prev.height - height) / 2" : "(parent.height - height) / 2");
break;
case TextAlignEnum.LeftBottom:
rtxt.X = ion == ImageOn.Left ? "prev.right" : "0";
rtxt.Y = ion == ImageOn.Bottom ? "prev.top - height" : "parent.height - height";
break;
case TextAlignEnum.CenterTop:
rtxt.X = ion == ImageOn.Left ? "prev.right + (parent.width - prev.width - width) / 2" :
(ion == ImageOn.Right ? "(parent.width - prev.width - width) / 2" : "(parent.width - width) / 2");
rtxt.Y = ion == ImageOn.Top ? "prev.bottom" : "0";
break;
case TextAlignEnum.CenterCenter:
rtxt.X = ion == ImageOn.Left ? "prev.right + (parent.width - prev.width - width) / 2" :
(ion == ImageOn.Right ? "(parent.width - prev.width - width) / 2" : "(parent.width - width) / 2");
rtxt.Y = ion == ImageOn.Top ? "prev.bottom + (parent.height - prev.height - height) / 2" :
(ion == ImageOn.Bottom ? "(parent.height - prev.height - height) / 2" : "(parent.height - height) / 2");
break;
case TextAlignEnum.CenterBottom:
rtxt.X = ion == ImageOn.Left ? "prev.right + (parent.width - prev.width - width) / 2" :
(ion == ImageOn.Right ? "(parent.width - prev.width - width) / 2" : "(parent.width - width) / 2");
rtxt.Y = ion == ImageOn.Bottom ? "prev.top - height" : "parent.height - height";
break;
case TextAlignEnum.RightTop:
rtxt.X = ion == ImageOn.Right ? "prev.left - width" : "parent.width - width";
rtxt.Y = ion == ImageOn.Top ? "prev.bottom" : "0";
break;
case TextAlignEnum.RightCenter:
rtxt.X = ion == ImageOn.Right ? "prev.left - width" : "parent.width - width";
rtxt.Y = ion == ImageOn.Top ? "prev.bottom + (parent.height - prev.height - height) / 2" :
(ion == ImageOn.Bottom ? "(parent.height - prev.height - height) / 2" : "(parent.height - height) / 2");
break;
case TextAlignEnum.RightBottom:
rtxt.X = ion == ImageOn.Right ? "prev.left - width" : "parent.width - width";
rtxt.Y = ion == ImageOn.Bottom ? "prev.top - height" : "parent.height - height";
break;
default:
// "general" alignments should not get here
Debug.Assert(false);
break;
}
}
