HOWTO: Insert Existing Projects as Sub-Projects

• The development environment included with: - Microsoft Visual C++, 32-bit Edition, version 4.0

SUMMARY

There is currently no way to insert an existing project as a project or subproject of the current workspace. The Insert menu has a Projects command that you can use to create new projects and sub-projects for the workspace, but you can't use it to insert projects into the workspace.

However, you can create a new sub-project of type makefile and insert a link from it to an existing project's makefile. This provides one of the major benefits of a sub-project; when the main project is building, it will do a 'make' of the linked project.

If you have a project that creates a library, and in another workspace you have a project to create an .exe file that uses the library, you can create a makefile sub-project in the .exe project that contains commands to build a library project. When building the main (.exe) project, if a dependent file of the linked (library) project is out of date, the file and the library will be re-built, and the changes will be incorporated into the main project.

Because the project is not truly inserted into the workspace, the project workspace window will not be able to display class, file, or resource information about the linked project.

MORE INFORMATION

Step-by-Step Procedure

From a project workspace, to create a sub-project link to an existing separate project, follow these steps:

1. On the Insert menu, click Projects. This will bring up the Insert Project dialog box that can create (but not insert existing) projects. To get here another way, you can on Build menu, click Subprojects, and then click New.

2. From the Insert Project dialog box, select a Project of type Makefile. Specify a project name and whether or not it is to be a subproject of an existing project.

3. Click Create, and then click Yes. This takes you directly to the Project Settings dialog box for this new project.

4. In the Settings For list, select a configuration of the new makefile sub-project that matches one of the configurations of the main project. For example, select the Win32 Debug configuration. This is important because when you build a main project, Developer's Studio will look for the matching sub-project configuration and build that. If there is no matching sub-project configuration, the sub-project will be ignored.

5. Click the General tab, remove the NMAKE command from the build command line, and instead invoke a batch file to run NMAKE on the existing project makefile. A batch file is required because project makefiles use relative paths, and the current directory must be set to the directory of the project makefile - something you can do in a batch file. For example, the command for the Win32 Debug configuration should look something like this one:

   c:\MyOldProject\MyOldProject.bat "MyOldProject - Win32 Debug"

   If the old project was created by Visual C++ 2.0, the string would be "Win32 Debug" - look in the makefile to be sure.

   If you always want the sub-project built the same way for all configurations, just have the same batch command for each configuration.

   In this sample, the batch file is in main directory of the old existing project. It works well there because that makes it easy to include the project in the sub-projects of any other new projects you might create.

6. Note the Rebuild all option. When you use the Rebuild all option on the main project, this option will be passed as a parameter to your batch file. This is best left "/a".

7. Change the Output file name to the actual library or .exe file that will be created, and be sure to specify the full path.

8. Do steps 4-5 for each configuration you will use.

9. Write the batch file to change the working directory to that of the original project directory, and then invoke NMAKE on the project's .mak file. The batch file can also pass along the arguments for rebuild all and the configuration specifier. For example:

   cd c:\MyOldProject nmake %2 -f MyOldProject.mak CFG=%1

   Given the build command listed in step 5, %1 will contain the configuration string and %2 will contain the rebuild all option (which will be blank for normal builds).

   NOTE: the batch file must not contain any commands for user interaction such as PAUSE. The output of the batch file is sent to the debug window, which is display only. Developer's Studio will hang waiting for input from the user in a window that does not allow input.

Keywords          : NmakeIss VwbIss
Version           : WINNT:4.0;
Platform          : NT WINDOWS
Issue type        : kbhowto