I am not worried about screen real estate. They have changed behavior and added new methods for tablet support. If I call one of these I assume that would cause a run-time failure for the older SDKs. Does this cause me to need a separate tablet version? This is the first time I have had to deal with this on Android and it wasn't clear to me what to do.
Documentation was incorrect and it worked. Don't know why I didn't think of reflection (doh!).
If those methods resides in some classes, which are not the part of pre-honeycomb SDK's you can try to use reflection to get (or not to in case of older devices) a honeycomb's class instance and call it's methods.
If you tell what methods/classes you are trying to use, i can try to make my answer more specific.
Related
I'm developing Windows Phone 8.1 WinRT application (Universal App), which is based on MapControl control.
The problem with it is that, for unknown reasons to me, when I call MapControl.SetLocation() method, I get AccessViolationException. It does not always happen - in fact I've been using that method for quite a long time and everything was fine. But now I'm developing new functionality - it boils down to porting code from MSDN (pushpin clustering) - MSDN Sample. Code contains some callback logic, some async/await usages. The problem is in mentioned earlier SetLocation(). I don't know why it throws exceptions.
What I've tried:
I'm working with MVVMLight, so experimented a lot with DispatcherHelper.CheckBeginInvokeOnUI(). Nothing.
Tried to make sure whether creating the pushpin object happens in UI thread - I don't know how to do that in the debugger (shall I check the tasks windows, or the threads window).
I don't post any code, because, as you can imagine, it's quite a lot of it - and I don't know if that would be any of use. So, my question is, do you know what might cause throwing AccessViolationException when invoking CheckBeginInvokeOnUI? Maybe there are some kind of constraints that I'm not aware of.
I've found some guides on using shared memory in Ansroid OS. I've learned that shm_open is not exist in Android amymore due to memory leaks caused by forced killing processes by OS or user.
ASHMEM functions are developed instead. But I cannot find in my NDK the declaration of ashmem_create_region() and other function. Where they are?
As with so many things in Android, the answer is to use JNI. The Java class java.nio.MappedByteBuffer wraps ashmem and provides read/write methods to access it.
Unfortunately, if you're using shared memory to boost performance, multiple round trips through JNI aren't an attractive proposition. Cedric Fung proposes using reflection to retrieve the ashmem handle by name, which will work but may break in future frameworks. (This does happen, BTW. All it takes is somebody deciding that "mFD" is too vague and "mFileDescriptor" would be a better name, or some such.) If you want to play with fire, I'd suggest retrieving the descriptor by type rather than by name, since the type is very unlikely to change.
Cedric also proposes implementing a Binder in C++, but this puts you back where you started because Binder is also not included in the NDK. Instead, you'd need to pass the handle via a binder service implemented in Java.
It's a lot of work for such a simple feature, I know. It's easier to just mmap a file and use that instead, which is too bad since a basic file mapping isn't nearly as mobile-friendly as ashmem. :-(
the header is inside system/core/include/cutils/ashmem.h of the aosp.
You must not use it for a regular application as ashmem functions aren't part of the NDK:
https://groups.google.com/forum/#!topic/android-ndk/eS9QK8EY968
I have here a C++/CLI solution which isn't mixed with native C++ (although we have this type too). It consists of three projects, where are two relevant for my question.
The first one is a static library (.lib) and deals with Acitve Diretytory matters.
The second one is the executable main project (.exe) which depends on the other projects.
I'm new to Visual Studio 2012 and want to use the advantages of tools like the code analysis. Running the code analysis over the solution reveals several CA2122 warnings:
CA2122 Do not indirectly expose methods with link demands
I understand the security concerns related to this warning and I think I understood how to deal with it, although I'm also new to this security stuff. This warnings are related to the Active Directory code when the whole solution is examined, while examining only the lib-project they will not appear and everything seems to be ok.
Now to the core of the problem:
I tried to mark all methods where I'm warned with the SecuritySafeCritical attribute
--> no changes, same warnings
I've solved this warning in another project by marking the whole assembly as SecurityCritical and adding the SecuritySafeCritical to the problematic method. This will not work since adding a AssemblyInfo.cpp with marking the assembly as SecurityCritical will not affect this problem. (I know that *.cpp seem to be obsolete in managed static librarys since the code seem to have to be complete in the header files making this kind of project obsolete... but we don't want to have .dll for every small part and we also want to have this stuff capsulated in an own project instead of having some loose header files or have it mixed with other regions)
After that I tried to mark the whole assembly of the main project as SecurityTransparent because so far I understand this SecuritySafeCritical marked code can be called by SecurityTransparent or SecurityCritical code (what is for me every kind of security). --> My as SecuritySafeCritical marked methods now are marked with CA2141 warnings and many other methods produce new warnings (most of them are related to exception handling):
CA2141:Transparent methods must not satisfy LinkDemands
CA2140: Transparent code must not reference security critical items
So I decided to try marking this assembly as SecurityCritical too.
--> My SecuritySafeCritical methods finally produce no warnings, but there are still all these other warnings from methods having exceptionhandling.
So I don't know how to solve this problem. I assume that having a managed static library is the problem and when having just a dll-project maybe I could solve the problem as mentionend in 2., but I want to avoid to share another *.dll project with our programs.
I searched for a solution but found nothing which would help in this case. Also informations on this topic are rare, out of date (because related to .Net Framework 2.0 while the whole security thing seems to be changed massively with .Net Framework 4.0) or hard to understand for me. So I hope someone has an idea what I could try or what I should do.
I have updated my development system to the new MonoTouch (6.0.1) and now whenever I'm referencing zxing.Monotouch types I get MissingMethodException on the constructor.
System.MissingMethodException: Method not found: 'MyClass..ctor'.
It's been 3 days now...
Anyone got any idea? I'm even willing to give up zxing if that what it takes (even though it's a wonderful library).
Edit
When I include zxing.Monotouch in the solution and reference it as a project the problem does not reproduce. If that's a clue I've missed it...
It's likely that the binary version of zxing.Monotouch is trying to access something that does not exists in 6.0.1. That's uncommon as we try to maintain source/binary compatibility unless the code is really broken (e.g. it would cause a crash anyway). I cannot be more precise without more data (e.g. a full build log).
If you include zxing.Monotouch as a reference then it will be rebuilt. If it works then it really looks like source compatibility was preserved (but not binary compatibility).
Whenever you have the source code available I encourage you to use .csproj (not .dll) references. Is has a few advantages, including the source/binary compatibility (above) and the fact that it makes things easier to debug from your project.
I need some basic clarification on C++ static linkage. I have a file called data_client.lib. There are three independant consumers for the library file a.exe, b.exe and c.exe. There is a service called data_server.exe for which data_client.lib is the interface. Actually, I added another function to data_server.exe and corresponding interface to data_client.lib. Since just a.exe needs the extra functionality, I build a.exe only. I shipped data_server.exe, data_client.exe and a.exe as patch. Now, b.exe and c.exe randomly/inconsistently crashes throwing
mfc42u!CException::`RTTI Complete
Object Locator'+0x10
Does it make sense? If I also build b.exe and c.exe, then the crash does not happen. Is this the way it works?
Actually, I added another function to data_server.exe and corresponding interface to data_client.lib.
It's a little unclear from this exactly what was added to your library. However, if it's a new method or methods added to a class (rather than just some new standalone functions), there's a very high chance that recompiling everything will fix your problem. The vtable may or may not have been thrown out of whack by your changes.
It's also possible that your crashes have absolutely nothing to do with this and there's some other problem going on... but from your description, my money's on a vtable issue. If it were me, I'd recompile b.exe and c.exe and test again before investigating other issues.
Maybe You don't have explicit dependencies, but some of Your project headers uses, or put information implicitly into your library.
I do not know about the error, but your applications b.exe and c.exe are using an older version of the binding lib to communicate with a newer version of the data_server.exe. Some v_table indexes might be off or something if you added a function. You definately have to rebuild all the libraries.