Highlight, HighlightRow, HighlightRowLineWidth

These three properties, along with the SelectOnEntry property of the controls within a grid’s cells, determine whether cell contents in a grid are highlighted when you move into the cell. The effects you can create with them are a little strange.

Usage

grdGrid.HighlightRow = lColoredBorder
lColoredBorder = grdGrid.HighlightRow
grdGrid.Highlight = lAllowHighlights
lAllowHighlights = grdGrid.Highlight
grcGrid.HighlightRowLineWidth = nHighlightRowWidth
nHighlightRowLineWidth = grcGrid.HighlightRowLineWidth

There are two kinds of highlighting for each cell in a grid. First, there’s a focus highlight that indicates which cell has focus—the border of the cell is colored. This highlight is controlled by HighlightRow, which was added in VFP 5. When you turn this one off, you don’t actually get rid of the focus highlight—it just changes from colored and noticeable to a just barely visible thickening of the cell border. It appears that the non-highlight is always a pale gray, though, no matter what color your grid lines are. VFP 7 added a new capability to surround the whole record with a line. If HighlightRow is true, then the record has a box just inside the grid lines drawn to the width specified in the HighlightRowLineWidth property. This property can have a value from 0 to 7. Fair warning: Borders wider than 2 pixels can look pretty strange. They can be drawn over the first part of the first character in a left-justified first column, and can do the same to the right-justified character in the last column. This isn’t the most aesthetic way of highlighting a row.

The second kind of highlight pertains to a grid cell. Normally when you tab into a grid cell, the text there is selected (highlighted). Two properties can change this. Highlight changes it for the whole grid. By default, it’s True, setting highlighting on for all columns of the grid. We’d be inclined to turn highlighting off when a grid is read-only. The highlight confuses people in that case.

The other property that controls highlighting is the column’s SelectOnEntry. Once you turn highlighting on for the grid, you can then control each column individually.

We should point out that, even with all the relevant settings turned on, you don’t get the whole row highlighted the way you do in lists. Even with VFP 7’s HighlightRowLineWidth property, you still get an interesting effect (when wide lines are used, say, greater than HighlightRowLineWidth = 2, well, let’s just say they’re not quite up to our aesthetic standards). Grids are not lists, and you would have to do some more tricks, including setting DynamicBackColor for every column. Christof Lange published a very complete solution to the problem in the Ask Advisor column in the November ‘98 issue of FoxPro Advisor.

When HighlightRow is .F., but Highlight is .T., the highlighting of individual cells looks pretty strange.

Example

ThisForm.grdReference.HighlightRow = .F.  && No focus highlight
ThisForm.grdReference.Highlight = .F.  && No highlight of
                 && contents, either

* This sets the highlight box to 2 pixels wide
ThisForm.grdReference.HighlightRow = .T.  && Turn on highlight
ThisForm.grdReference.HighlightRowLineWidth = 2

See Also

GridLines, SelectOnEntry