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LabWindows/CVI Release Notes for Windows 20 © National Instruments Corporation
Obsolete Value for X and Y Resolution
For the
ATTR_PRINT_XRESOLUTION
and
ATTR_PRINT_YRESOLUTION
attributes,
VAL_USE_PRINTER_SETTING
replaces
VAL_USE_PRINTER_DEFAULT
, which is obsolete.
The actual value, –1, remains the same.
In previous versions of LabWindows/CVI, the
VAL_USE_PRINTER_DEFAULT
value does not
have the same behavior that
VAL_USE_PRINTER_SETTINGS
does now. If you set an attribute
to
VAL_USE_PRINTER_DEFAULT
, the attribute retains that value. This has two consequences.
First, you cannot use
GetPrintAttribute
to find out the actual value that was used.
Second, LabWindows/CVI uses the most recent printer setting each time you call a print
function, even if you set the attribute to
VAL_USE_PRINTER_DEFAULT
only once.
Now that
VAL_USE_PRINTER_SETTING
causes LabWindows/CVI to save the current
system setting as the attribute value, there is no reason to overwrite that value with the
current system setting on the next print function call. If the user changes the setting in
the printer-specific dialog box, most likely, you should use the modified value in subsequent
print calls.
Warning of Modified Behavior
When the Run-time Engine for LabWindows/CVI 5.0 is installed, it overwrites previous
versions of the Run-time Engine. Thus, executables on a computer with the new Run-time
Engine use the new print dialog box.
In addition, any executable that used
VAL_USE_PRINTER_DEFAULT
for
ATTR_PRINT_XRESOLUTION
or
ATTR_PRINT_XRESOLUTION
has the modified behavior
of
VAL_USE_PRINTER_SETTING
, as described in the Using Windows System Printer
Settings section earlier in this document.
Revised Constant Names
The constant names for several attributes and values have changed, but the actual values
remain the same. The obsolete constant names remain in the
userint.h
include file, so you
do not have to change your source code.
The changes to attribute constant names are as follows:
•
ATTR_PRINT_AREA_HEIGHT
replaces
ATTR_PAPER_HEIGHT
.
•
ATTR_PRINT_AREA_WIDTH
replaces
ATTR_PAPER_WIDTH
.
• For
ATTR_PRINT_AREA_HEIGHT
and
ATTR_PRINT_AREA_WIDTH
,
VAL_USE_ENTIRE_PAPER
replaces
VAL_USE_PRINTER_DEFAULT
.
• For
ATTR_XOFFSET
and
ATTR_YOFFSET
,
VAL_CENTER_ON_PAPER
replaces
VAL_USE_PRINTER_DEFAULT
.
• For
ATTR_XRESOLUTION
and
ATTR_YRESOLUTION
,
VAL_USE_PRINTER_SETTING
replaces
VAL_USE_PRINTER_DEFAULT
.