DEFINE WINDOW Syntax and "Position Off Screen" Error (104056)
The information in this article applies to:
- Microsoft Visual FoxPro for Windows 3.0
- Microsoft FoxPro for Windows 2.5
- Microsoft FoxPro for Windows 2.5a
- Microsoft FoxPro for MS-DOS 2.0
- Microsoft FoxPro for MS-DOS 2.5
- Microsoft FoxPro for MS-DOS 2.5a
This article was previously published under Q104056 SUMMARY
The DEFINE WINDOW clause can use either the FROM ... TO syntax or the
AT ... SIZE syntax to dimension the window.
AT ... SIZE sizes the window according to the font of the defined
window itself.
FROM ... TO sizes the window according to the font of the window if
there is not an explicit FONT clause on the DEFINE WINDOW command;
FROM ... TO with an explicit FONT clause sizes the window according to
the font of the screen or parent window.
MORE INFORMATION
DEFINE WINDOW <window name> FROM <row1>,<col1> TO <row2>,<col2> uses
the font of the screen or parent window to locate the upper/left
corner (row1,col1). It then uses "foxfont",9 (the default font of a
window) to position the lower/right corner (row2,col2). The same
amount of information can be placed in the window as is possible in
FoxPro for MS-DOS.
If a FONT clause is included in the DEFINE WINDOW ... FROM ... TO
command, the command uses the font of the screen or parent window to
locate the lower/right corner (row2,col2). This behavior ensures that
the dimensions of the window relate to other objects on the screen and
other windows in the same way that they do in FoxPro for MS-DOS.
DEFINE WINDOW <window name> AT <row1>,<col1> SIZE <row2>,<col2> also
uses the font of the screen or parent window to locate the upper/left
corner of the window (row1,col1). It always uses the font of the
defined window to position the lower/right corner (row2,col2). This
behavior ensures that the same amount of information can always be
placed in the window regardless of its font.
Potential Problems
When you are using the DEFINE WINDOW ... FROM ... TO syntax, if the
window font is smaller than the screen font/parent window font, you
may receive "position off screen" errors in code that appears to be
correct. Remember that when writing to the window you always use the
window font. If the window is sized according to the font of the
parent window/screen and that font is smaller, there will be fewer
usable rows and columns than you might expect.
Platform Differences
In FoxPro for Windows, the four corners of the window will be at the
upper/left corners of the row/column coordinates. This is slightly
different from FoxPro for MS-DOS, which uses the line-drawing
characters and bisects the row/column coordinate.
The window borders do not take up a row/column of their own as they
do in FoxPro for MS-DOS.
| Modification Type: | Major | Last Reviewed: | 12/3/2003 |
|---|
| Keywords: | KB104056 |
|---|
|