I have two projects within one solution. Both projects contain some files that are the same. For instance, Project1 contains shared.cpp and so does Project2. However, when I edit shared.cpp and build both projects, is there any way I can make VC++ compile the source file once, then use the single object file in the linking of the two projects, rather than compiling it twice? The obvious purpose being to decrease build time.
Put shared.cpp in a separate project in the same solution and make it build as a library. Then add that project as a dependency to project1 and project2.
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Well i have a build setup of 2 projects, one project takes .xml files from a directory and processes them into header files. These files are then used by the second project. Is there any way to check if his project needs to be re-run (the .xml files were modified or a new one was added)?
Just combine the two projects into one common source tree, and one single SConstruct (with as many SConscripts as you like in the subfolders, that get included by SConscript(file) ).
Then ensure that the header files in the include/ folder are always tried to be built, e.g. by adding them as default targets with env.Default().
SCons will only call each conversion .xml->.h when the corresponding source XML file has changed its content.
Probably a pretty fundamental question. When developing a single-project-solution in MSVC++ everything makes a lot of sense, every file is visible to the compiler. When moving to a multiple project solution, none of the interface elements governing project dependence seem to make sense (coming from a .net background.)
For starters it appears setting up project dependencies with that terminology seems to only imply what order the projects are compiled in. There is no more function attached to the definition and addressing objects or methods of one project from another will not work. #including the headers of the dependency doesn't seem to work either, so the dependent project cannot see the files of its dependency. Copying a link of a header from one project to another doesn't work either, where for two projects under the 'Header Files' section, the same file is referenced in both locations. Even with this header references do not work and the files are unconnected. The only way of creating a functional dependency is to add the dependency's paths to the linker/compiler search path of the dependent or worse, simply copying the files of one project to another.
Either I'm missing something or the .NET Visual Studio IDEs have succeeded at what the VC++ IDE has badly failed at.
Edit:
For the sake of asking a specific question, take the following steps for creating a solution in VC++ and I ask if the missing step(s) can be filled in:
Create empty DLL project inside new solution.
Create method in DLL project and compile.
Create new empty executable project.
Create main method in new project.
...
Have main method call function in DLL project.
Preferably fill in the missing step(s) with the most most modern/industry standard/best practice method that best maintains project modularity as intended.
From this I would expect to independently be able to extrapolate and create classes, enumerations etc. in the DLL class and access them all in the executable project, so long as I can find out how this is intended to be done.
In step 2, as per the usual C++ rules, declare the method in the header. Read up on __declspec(DllExport) since the default is that methods are internal to the DLL.
In step 5, as per the usual C++ rules, include the header. Visual C++ needs to know where the header is coming from, so you need to reference the source project. Details vary between Visual Studio versions.
In step 6, you call the method in the normal way. Since it's now declared as __declspec(DllImport), the compiler will leave it to the linker, and the linker will get it from the correct DLL.
Consider a solution has 2 projects: ProjectA and ProjectB (both are MonoTouch apps) and ProjectBase. ProjectBase contains the whole application, but Main.cs file (with the entry point) is located in ProjectA and ProjectB (which reference ProjectBase). This way, running any of A/B projects will boot up the application from ProjectBase.
Now, I want to override something for ProjectA only (it might be XIB file, image or a .NET class). Is there any way I can setup the solution so that the code and resources, produced by ProjectBase, are merged with the ones from ProjectA/ProjectB and the latter wins?
I found (probably a quirky and kinda-undefined-behavior-driven way) of overriding XIBs: I just put a XIB into ProjectA and ProjectB, name it the same as it was named in ProjectBase and them exclude it from ProjectBase. Although MonoDevelop compiles all items, it seems that the startup project's XIBs get priority, so that I see ProjectA-specific XIBs when I launch ProjectA and ProjectB-specific XIBs when I launch ProjectB. However, I am not sure it is the way it should behave, plus, from what I can see from build log, ALL projects get built yielding resources at the end.
P.S. I'm sorry if this has been asked previously, but I was not able to find the similar question on SO.
I was once trying to do this for a bunch of apps. I would have thought build order would be ProjectBase and then ProjectA, and the content copy system would be the same... Guess this means we are wrong.
You could do a few things.
A) Build your own program to copy resources which are marked for content. Would not be very hard, just need to read the .csproj files. XML parsing is easy enough in .NET. Run this program on post build. Would just have to be careful when doing builds such as to zip or to the device as I am not sure how it handles post-build events.
B) [This is what I did instead] If I expect to also make ProjectC, ProjectD ... ProjectN I instead made a program to generate my program... (Programception).
What it does, has ProjectBase, and ProjectTempalte. You enter your new project name into this program, say, "MyNewProject" and it will create the correct folder structure, write the correct csproj files, and update SLN file. ProjectTemplate has various placeholders in .csproj files like {PLACEHOLDER} which Programception would just go through and find/replace with my project name. Image files (and in your case XIB) are then only kept within ProjectA (B..C..N) unless I do not expect to try and override them in which case they would stay in ProjectBase. This is a lot easier with a XIBless application I would assume. I never use XIB's anyway.
Hope that helps!
I have multiple native C++ projects, one of them is a dll project, and I want to test it.
The problem is that the generated .lib file only contains the definitions for the public interface of the dll, but I would like to test the projects internals.
Since referencing the project does not work (it only works for static libraries) is there a way to add the the generated objs directly in my testing project ?
Also I know that I could include all the source code files in the referenced project. But is there a way to do this considering that the referenced project might change. I would like a method that does not force me to mange each file manually.
I have done some research and I found some answers like in this question:
Reusing object files in Visual Studio 2005
but since I have many small classes exposing all the classes is a bit to tedious.
I found that I can set a Pre Link Event in the Build Event menu.
This allows me to use the following command:
lib -out:"../Debug/tempAllDllObjects.lib" "../MyDLLProject/Debug/*.obj"
now, even if my project is a DLL project I have an additional .lib file that contains all the objects in my project. All I have to do is reference the newly created lib file. This way I can link with all the objects in my DLL project even if they are not in the public interface.
As a note the command can also be set on the DLL project as a Postbuild Event this will increase the efficiency since now the lib file is only generated when changes occur.
How can I share source code between 2 projects in MS Visual Studio 2008 (I'm programming in C++)?
In my case, I have the code for the main game project and now I want to make a simple model editor that uses the game's code, so that whenever I change/add some code in one project it will be updated in the second one.
A common method for doing this, (you'll see it everywhere in open-source packages), is to bundle all the headers into an 'include' folder and all the source into a 'source' folder.
Now in whatever project needs the code, you go to, 'Project Properties->c/c++->General->Additional Include Directories'. Then add the path to the 'include' directory. Finally, add the source/headers to your project, now both projects reference the exact same files, which are in a nice tidy shared location.
You can also build the shared code as a static library or better yet (IMO) a DLL. This involves creating a new project, and learning a little bit about the linker in VS 2008, but really nothing too complicated. This also has the advantage (in the case of a DLL) that the two projects don't re-compile the same code, but rather it is compiled once and used twice.
You can move the required classes into a separate library project and then references this from the second project. Any changes will be automatically picked up.
(I'm not a C++ developer, however the above works for C# projects, I would assume it works for C++ projects too)
You basically have two options:
Create a static library. In this, all the code in the library will be exported and visible to who ever links to this library.
Create a DLL: here, you can define what classes and methods you would like to export and use those.
Lets say you have a class called classA which is defined in classA.h and implemented in classA.cpp and you want to use this same class from two different applications (application B and application C).
Using method 1, you would create a static library by going to file->new win32 project and in the box that pops up, choose application settings and make it a "Static Library". Then in this static library you add both your classA.h and classA.cpp.
To use this static library in application B or C, goto the references and add a reference to the static library project that you just created. then include classA.h in your application (don't forget to set the additional include directories path) and you are good to go.
The approach is very similar for a DLL as well, the difference here would be that you can choose what parts of your code in the DLL are exported (ie visible to outside callers).
From an overall point of view:
With the static library approach, your code will be compiled into both the applications.
With the DLL approach, there will be just one copy of the shared code (in the DLL which will be a separate file) and this will be loaded as required.