Flash MX 2004 Games : Art to ActionScript

the Watch window, then you can see how
just these variables are behaving as you run
through the code. There is also a ‘locals’ tab,
which lists the variables that are declared in the
current function.
The buttons above the script pane allow the
developer to ‘Continue’, ‘Stop Debugging’,
‘Toggle Breakpoint’, ‘Remove All Breakpoints’,
‘Step Over’, ‘Step In’ and ‘Step Out’.
The last three allow the developer the ability to
study at close quarters how the code behaves.
Chapter 11: Debugging
Figure 11.9 Debugger toolbar
Step Over executes a single line of code in the current function.
Step In will take the playback head into a user-defined function if there is such a call on
the current line of code. Once inside the function you can use Step Over to examine
how the code behaves a line at a time.
Step Out only applies to a user-defined function. If the code pointer is currently inside
a user-defined function then that function is executed until there is a return from the
function, at which time the program halts.
Stepping through the code can be a very effective way of tracking down a persistent problem.
Remote debugging
You can even use the debugger to analyse a remote file on a web server. To enable remote
debugging you must ensure that you have taken two important steps.
Step 1
Enable remote debugging of the movie by selecting ‘File/Publish Settings’. The dialog box shown
in Figure 11.10 appears. Make sure that you have checked the box that says ‘Debugging Permitted’.
If necessary you can enter a password in the dialog box to make your file more secure. Then
publish your movie.
Step 2
When you publish the movie, Flash creates a file with the extension ‘swd’; this file has the same
name as the ‘swf’ file. It is essential that the ‘swd’ file be in the same location as the ‘swf’ file
for remote debugging to work fully. Without the ‘swd’ file Flash will not be able to stop at a
breakpoint or step through the code a line at a time.
Having made sure that you enabled debugging and that the ‘swd’ file resides at the same
URL as the ‘swf’ file, you are now ready to use remote debugging. Open the Debugger
window using ‘Window/Development Panels/Debugger’. Click the options icon in the top
right corner and make sure ‘Enable Remote Debugging’ is checked. Try running the file:
‘Examples/Chapter11/Remote.html’.
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