ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Printing
Flash runtime tasks and system printing
Flash Player 9 and later, Adobe AIR 1.0 and later
Because Flash runtimes dispatch pages to the operating system’s printing interface, be aware of the tasks managed by
Flash runtimes and the tasks managed by an operating system’s own printing interface. Flash runtimes can initiate a
print job, read some of a printer’s page settings, pass the content for a print job to the operating system, and verify if
the user or system has canceled a print job. Other processes, such as displaying printer specific dialog boxes, canceling
a spooled print job, or reporting on the printer’s status, are all handled by the operating system. Flash runtimes are able
to respond if there is a problem initiating or formatting a print job, but can report back only on certain properties or
conditions from the operating system’s printing interface. As a developer, your code needs to respond to these
properties or conditions.
Working with exceptions and returns
Flash Player 9 and later, Adobe AIR 1.0 and later
Check to see if the PrintJob.start() method returns true before executing addPage() and send() calls, in case
the user has canceled the print job. A simple way to check whether these methods have been canceled before
continuing is to wrap them in an if statement, as follows:
if (myPrintJob.start())
{
// addPage() and send() statements here
}
If PrintJob.start() is true, the user selected Print (or a Flash runtime, such as Flash Player or AIR, has initiated a
Print command). So, the addPage() and send() methods can be called.
Also, to help manage the printing process, Flash runtimes throw exceptions for the PrintJob.addPage() method, so
that you can catch errors and provide information and options to the user. If a PrintJob.addPage() method fails,
you can also call another function or stop the current print job. You catch these exceptions by embedding addPage()
calls within a try..catch statement, as in the following example. In the example, [params] is a placeholder for the
parameters specifying the actual content you want to print:
if (myPrintJob.start())
{
try
{
myPrintJob.addPage([params]);
}
catch (error:Error)
{
// Handle error,
}
myPrintJob.send();
}
After the print job starts, you can add the content using PrintJob.addPage() and see if that generates an exception
(for example, if the user has canceled the print job). If it does, you can add logic to the catch statement to provide the
user (or the Flash runtime) with information and options, or you can stop the current print job. If you add the page
successfully, you can proceed to send the pages to the printer using PrintJob.send().
Last updated 6/6/2012
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