Debugging ActionScript 3.0



    About the ActionScript 3.0 debugger

    Flash includes a separate debugger for ActionScript 3.0 that operates somewhat differently from the ActionScript 2.0 debugger. The ActionScript 3.0 debugger only works with ActionScript 3.0 FLA and AS files. FLA files must have publish settings set to Flash Player 9. When you initiate an ActionScript 3.0 debugging session, Flash launches the stand-alone debug version of Flash Player to play the SWF file. The debug Flash player plays the SWF in a separate window from the Flash authoring application window.

    The ActionScript 3.0 debugger converts the Flash workspace to a debug workspace that displays panels that are used for debugging, including the Actions panel and/or Script window, the Debug console, and the Variables panel. The Debug console displays the call stack and contains tools for stepping through scripts. The Variables panel displays the variables in the current scope with their values and allows you to update those values yourself.

    Additional resources

    The following resources provide additional detailed information about debugging ActionScript 3.0:

    Enter debugging mode

    The way you begin a debugging session depends on the type of file you are working on. During a debugging session, Flash interrupts the execution of ActionScript when it encounters a breakpoint or a runtime error.

    When Flash initiates a debug session, it adds special information to the SWF file that it exports for the session. This information allows the debugger to provide the specific line numbers in the code where errors are encountered.

    You can include this special debugging information in all SWF files created from a specific FLA file in the Publish settings. This allows you to debug the SWF file even if you do not explicitly initiate a debug session. This debugging information makes the SWF file slightly larger.

    Start debugging from a FLA file

     Select Debug > Debug Movie.

    Start debugging from an ActionScript 3.0 AS file

    1. With the ActionScript file open in the Script window, select the FLA file that the ActionScript file should be compiled with from the Target menu at the top of the Script window. The FLA file must also be open in Flash to appear in this menu.
    2. Select Debug > Debug Movie.

    Add debugging information to all SWF files created from a FLA file

    1. With the FLA file open, select File > Publish Settings.
    2. In the Publish Settings dialog box, click the Flash tab.
    3. Select Permit Debugging.

    Exit debugging mode

     Click the End Debug Session button in the Debug Console.

    Set and remove breakpoints

    Add breakpoints to ActionScript code to interrupt the execution of the code. After execution is interrupted, you can step through and execute the code line by line, view different sections of your ActionScript, view the values of variables and expressions, and edit variable values.

    Note: Breakpoints cannot be added to ASC (ActionScript for Communication) or JSFL (Flash JavaScript) files.

    Set a breakpoint

     In the Actions panel or Script window, click in the left margin next to the line of code where you want the breakpoint to appear.

    Remove a breakpoint

     In the Actions panel or Script window, click on the breakpoint to remove.

    Step through lines of code

    After the ActionScript execution is interrupted at a breakpoint or runtime error, you can step through the code line by line, choosing to step into function calls or step over them. You can also choose to continue executing the code without stepping.

    Step into code line by line

     Click the Step In button in the Debug Console.

    Step over a function call

     Click the Step Over button in the Debug Console.

    Step out of a function call

     Click the Step Out button in the Debug Console.

    Resume normal code execution

     Click the Continue button in the Debug Console.

    Display and examine scripts in the call stack

    When code execution stops in the debugger, you can view the call stack in the Debug Console and display the scripts containing the functions in the call stack. The call stack shows the current list of nested function calls that are waiting to complete execution.

    You can view the individual scripts that contain each function.

     In the Debug Console panel, double click the name of the script in the call stack.

    Display and modify variable values

    View and edit the values of variables and properties in the Variables panel.

    View a variable value

    1. In the Variables panel, select the types of variables to display from the Panel menu.

      • Show Constants displays the values constants (variables having a fixed value).

      • Show Statics displays variables that belong to the class, rather than to instances of the class.

      • Show Inaccessible Member Variables displays variables that are not accessible to other classes or namespaces. This includes variables that are protected, private or internal to the namespace.

      • Show Additional Hexadecimal Display adds hexadecimal values wherever decimal values are displayed. This is mainly useful for color values. Hexadecimal values are not displayed for decimal values from 0 through 9.

      • Show Qualified Names displays variables types with both the package name and the class name.

    2. Expand the tree view of the object structure of the FLA until you see the variable to view.

    Edit the value of a variable

    1. In the Variables panel, double click on the value of the variable.
    2. Enter the new value for the variable and press Enter. The new value is used during subsequent code execution.

    Control compiler warnings

    Control the types of compiler warnings that the ActionScript compiler generates in the Compiler Errors panel. When the compiler reports an error, double click the error to navigate to the line of code that caused the error.

    1. Select File > Publish Settings.
    2. Click Flash.
    3. Click the ActionScript Settings button.
    4. Select among the Errors options:

      • Strict Mode reports warnings as errors, which means that compilation will not succeed if those errors exist.

      • Warnings Mode reports extra warnings that are useful for discovering incompatibilities when updating ActionScript 2.0 code to ActionScript 3.0.

    Navigate to errors in code

    When Flash encounters an error in ActionScript code, either during compiling or execution, it reports the error in the Compiler Errors panel. Navigate to the line of code that caused the error from the Compiler Errors panel.

     Double click the error in the Compiler Errors panel.

    Debug a remote ActionScript 3.0 SWF file

    With ActionScript 3.0, you can debug a remote SWF file by using the stand-alone, ActiveX, or plug‑in version of the Debug Flash Player, which you can find in the Flash install directory/Players/Debug/ directory. However, in the ActionScript 3.0 Debugger, remote debugging is limited to files located on the same localhost as the Flash authoring application, being played in the stand alone debug player, ActiveX control, or plugin.

    To permit remote debugging of the file, enable debugging in the Publish settings. You can also publish your file with a debugging password to ensure that only trusted users can debug it.

    As in JavaScript or HTML, users can view client-side variables in ActionScript. To store variables securely, send them to a server-side application instead of storing them in your file. However, as a developer, you may have other trade secrets, such as movie clip structures, that you do not want to reveal. You can use a debugging password to protect your work.

    Enable remote debugging of a SWF file and set a debugging password

    In ActionScript 3.0 FLA files, code in frame scripts cannot be debugged. Only code in external AS files can be debugged with the ActionScript 3.0 Debugger.

    1. Open the FLA file.
    2. Select File > Publish Settings.
    3. On the Flash tab of the Publish Settings dialog box, select Permit Debugging.
    4. Close the Publish Settings dialog box, and select one of the following commands:

      • File > Export > Export Movie

      • File > Publish

    5. Leave the SWF file on the local machine to perform a remote debug session on the localhost, or upload it to your web server.

      The SWF file contains no breakpoint information, so if you upload the file to a remote server you will not be able to step through code. Use the localhost to perform this task.

    6. In Flash, select Debug > Begin Remote Debug Session > ActionScript 3.0.

      Flash opens the ActionScript 3.0 Debugger and waits for a debug Flash Player to connect. You have 2 minutes to start the debug Flash Player. If more than 2 minutes elapse, repeat this step.

    7. Open the SWF file in the debug version of the Flash Player plugin, ActiveX control, or stand-alone player. The debug stand-alone player is located in the Flash install directory/Players/Debug/ directory. Do not connect to a file on another machine, as debugger will not be able to receive any breakpoint information.

      The debug session begins when the debug player connects to the Flash ActionScript 3.0 Debugger panel.

    Activate the Debugger from a remote location

    1. Open the Flash authoring application if it is not already open.
    2. Select Debug > Begin Remote Debug Session > ActionScript 3.0.
    3. In a browser or in the debugger version of the stand-alone player, open the published SWF file from the remote location.

      If the Remote Debug dialog box does not appear, right-click (Windows) or Control-click (Macintosh) in the SWF file to display the context menu, and select Debugger.

    4. In the Remote Debug dialog box, select Localhost and select the file to open.

      The display list of the SWF file appears in the Debugger. If the SWF file doesn’t play, the Debugger might be paused, so click Continue to start it.