Importantly, we’ll link this library to the main project as a Resource Shared Library (RSL), which means that the objects from  patches,swc will not be merged into the code of the main application, but will be loaded during the run time. Add the compiler option -debug=false to your library project to avoid these annoying Flash Player’s messages asking where the debugger for this RSL is located.

Now go to the build path of the main Flex project and add patches.swc to the top of the list. Select the RSL linkage type as shown below (TestPatch there is the name of the main Flex project).

 


Go again to the properties of your main Flex project and add the library patches project in the list of your project’s references.

Run your main project – you should not see any differences because patches.swc does not contain any useful code yet.

Then, copy one of your classes from the main application it to the patches library project, modify it there and rebuild the patches.swc. Now we have two versions of this class – the new one in the patches.swc and the old one in the main application.

Re-run the main application.  You’ll see that the new version of the modified class is being used. The class loader picked the new version since patches.swc is located at the top of the classpath of your application. That’s all there is to it.

Every time you need to make minor changes in your production application, just put them in patches.swc and upload it to the production machine.