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  • Classic ASP application-wide initializations and object caching

    - by slack3r
    In classic ASP (which I am forced to use), I have a few factory functions, that is, functions that return classes. I use JScript. In one include file I use these factory functions to create some classes that are used throughout the application. This include file is included with the #include directive in all pages. These factory functions do some "heavy lifting" and I don't want them to be executed on every page load. So, to make this clear I have something like this: // factory.inc function make_class(arg1, arg2) { function klass() { //... } // ... Some heavy stuff return klass; } // init.inc, included everywhere <!-- #include FILE="factory.inc" --> // ... MyClass1 = make_class(myarg01, myarg02); MyClass2 = make_class(myarg11, myarg12); //... How can I achieve the same effect without calling make_class on every page load? I know that I can't cache the classes in the Application object I can't use the Application_OnStart hook in Global.asa I could probably create a scripting component, but I really don't want to do that So, is there something else I can do? Maybe some way to achieve caching of these classes, which are really objects in JScript. PS: [further clarification] In the above code "heavy stuff" is not so heavy, but I just want to know if there's a way to avoid it being executed all the time. It reads database meta information, builds a table of the primary keys in the database and another table that resolves strings to classes, etc.

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  • Generate and download a text file in javascript

    - by Mark B
    All my research so far suggests this can't be done, but I'm hoping someone here has some cunning ideas. I have a form on a website which allows users to bulk upload lots of URLs to add to a list on the server. There's quite a lot of server-side processing to do on each URL, so to avoid timeouts and to display progress, I've implemented the upload using jQuery to submit the URLs one at a time using ajax. This is all working nicely. However, part of the processing on each URL is deduplicating it against the complete list. The ajax call returns a status indicating either a successful upload or a rejection due to duplication. As the upload progresses, I tell the user how many URLs have been rejected as duplicates (along with overall progress and ETA). The problem now is how to give the user a complete list of the failed duplicate URLs. I've kept them in an array in my jQuery, and would like the user to be able to click on a link on the form to download a text file containing those URLs. Is this possible just using client-side processing? The server-side processing basically handles a single keyword at a time. I'd rather not have to store the duplicates in a database table with some kind of session key which gets sent with every ajax call, and is then used at the end to generate the text file server-side (and then gets cleaned up some time later). I can see how to do this, but it seems very clunky and a bit 20th century.

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  • Model-binding an object from the repository by several keys

    - by Anton
    Suppose the following route: {region}/{storehouse}/{controller}/{action} These two parameters region and storehouse altogether identify a single entity - a Storehouse. Thus, a bunch of controllers are being called in the context of some storehouse. And I'd like to write actions like this: public ActionResult SomeAction(Storehouse storehouse, ...) Here I can read your thoughts: "Write custom model binder, man". I do. However, the question is How to avoid magic strings within custom model binder? Here is my current code: public class StorehouseModelBinder : IModelBinder { readonly IStorehouseRepository repository; public StorehouseModelBinder(IStorehouseRepository repository) { this.repository = repository; } public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) { var region = bindingContext.ValueProvider.GetValue("region").AttemptedValue; var storehouse = bindingContext.ValueProvider.GetValue("storehouse").AttemptedValue; return repository.GetByKey(region, storehouse); } } If there was a single key, bindingContext.ModelName could be used... Probably, there is another way to supply all the actions with a Storehouse object, i.e. declaring it as a property of the controller and populating it in the Controller.Initialize.

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  • What is the proper way to set my drawable directories to support the new Dell Streak without losing support for older devices?

    - by emmby
    This seems to be a widespread problem. I have the following drawable directories: drwxr-xr-x 18 mike staff 612 Feb 4 17:28 drawable/ drwxr-xr-x 51 mike staff 1734 Feb 4 17:32 drawable-nodpi/ drwxr-xr-x 44 mike staff 1496 Feb 4 17:30 drawable-normal-mdpi/ My xml drawable resources are in drawable. My resources intended for the large-mdpi (Dell Streak) and normal-hdpi (Droid, Nexus, Incredible, etc.) are all in drawable-nodpi. My resources for normal-mdpi (older phones like the G1) are in drawable-normal-mdpi. Unfortunately, the normal-hdpi phones like the Droid are pulling their resources from drawable-normal-mdpi instead of from drawable-nodpi. This is likely because of the rules in How Android Finds the Best-matching Resource. So the question is, how do I provide support for large-mdpi devices like the Streak along with normal-hdpi devices like the Droid, as well as normal-mdpi devices like the G1? The simplest solution would probably be to make two copies of my large resources, one in normal-hdpi for the droid and one in large-mdpi for the streak, but i'd like to avoid duplicating all of these resources. Update Per Mayra's suggestion, I could make an alias for every resource. However, there are a lot of resources I'd have to make aliases for, which would make maintenance a nightmare going forward, so I'm hoping for another solution.

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  • C++ - passing references to boost::shared_ptr

    - by abigagli
    If I have a function that needs to work with a shared_ptr, wouldn't it be more efficient to pass it a reference to it (so to avoid copying the shared_ptr object)? What are the possible bad side effects? I envision two possible cases: 1) inside the function a copy is made of the argument, like in ClassA::take_copy_of_sp(boost::shared_ptr<foo> &sp) { ... m_sp_member=sp; //This will copy the object, incrementing refcount ... } 2) inside the function the argument is only used, like in Class::only_work_with_sp(boost::shared_ptr<foo> &sp) //Again, no copy here { ... sp->do_something(); ... } I can't see in both cases a good reason to pass the boost::shared_ptr by value instead of by reference. Passing by value would only "temporarily" increment the reference count due to the copying, and then decrement it when exiting the function scope. Am I overlooking something? Andrea. EDIT: Just to clarify, after reading several answers : I perfectly agree on the premature-optimization concerns, and I alwasy try to first-profile-then-work-on-the-hotspots. My question was more from a purely technical code-point-of-view, if you know what I mean.

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  • Moving from a non-clustered PK to a clustered PK in SQL 2005

    - by adaptr
    HI all, I recently asked this question in another thread, and thought I would reproduce it here with my solution: What if I have an auto-increment INT as my non-clustered primary key, and there are about 15 foreign keys defined to it ? (snide comment about original designer being braindead in the original :) ) This is a 15M row table, on a live database, SQL Standard, so dropping indexes is out of the question. Even temporarily dropping the foreign key constraints will be difficult. I'm curious if anybody has a solution that causes minimal downtime. I tested this in our testing environment and finally found that the downtime wasn't as severe as I had originally feared. I ended up writing a script that drops all FK constraints, then drops the non-clustered key, re-creates the PK as a clustered index, and finally re-created all FKs WITH NOCHECK to avoid trawling through all FKs to check constraint compliance. Then I just enable the CHECK constraints to enable constraint checking from that point onwards, and all is dandy :) The most important thing to realize is that during the time the FKs are absent, there MUST NOT be any INSERTs or DELETEs on the parent table, as this may break the constraints and cause issues in the future. The total time taken for clustering a 15M row, 800MB index was ~4 minutes :)

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  • Threshold of blurry image - part 2

    - by 1''
    How can I threshold this blurry image to make the digits as clear as possible? In a previous post, I tried adaptively thresholding a blurry image (left), which resulted in distorted and disconnected digits (right): Since then, I've tried using a morphological closing operation as described in this post to make the brightness of the image uniform: If I adaptively threshold this image, I don't get significantly better results. However, because the brightness is approximately uniform, I can now use an ordinary threshold: This is a lot better than before, but I have two problems: I had to manually choose the threshold value. Although the closing operation results in uniform brightness, the level of brightness might be different for other images. Different parts of the image would do better with slight variations in the threshold level. For instance, the 9 and 7 in the top left come out partially faded and should have a lower threshold, while some of the 6s have fused into 8s and should have a higher threshold. I thought that going back to an adaptive threshold, but with a very large block size (1/9th of the image) would solve both problems. Instead, I end up with a weird "halo effect" where the centre of the image is a lot brighter, but the edges are about the same as the normally-thresholded image: Edit: remi suggested morphologically opening the thresholded image at the top right of this post. This doesn't work too well. Using elliptical kernels, only a 3x3 is small enough to avoid obliterating the image entirely, and even then there are significant breakages in the digits:

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  • Clone existing structs with different alignment in Visual C++

    - by Crend King
    Is there a way to clone an existing struct with different member alignment in Visual C++? Here is the background: I use an 3rd-party library, which uses several structs. To fill up the structs, I pass the address of the struct instances to some functions. Unfortunately, the functions only returns unaligned buffer, so that data of some members are always wrong. /Zp is out of choice, since it breaks the other parts of the program. I know #pragma pack modifies the alignment of the following struct, but I would like to avoid copying the structs into my code, for the definitions in the library might change in the future. Sample code: test.h: struct am_aligned { BYTE data1[10]; ULONG data2; }; test.cpp: #include "test.h" // typedef alignment(1) struct am_aligned am_unaligned; int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { char buffer[20] = {}; for (int i = 0; i < sizeof(unaligned_struct); i++) { buffer[i] = i; } am_aligned instance = *(am_aligned*) buffer; return 0; } Consider am_aligned is defined in the library header file. am_unaligned is my custom declaration, and only effective in test.cpp. The commented line does not work of course. instance.data2 is 0x0f0e0d0c, while 0x0d0c0b0a is desired. Thanks for help!

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  • SVN 409 conflict on commits and updates

    - by bhefny
    We have been using SVN for the past year now and when we migrated to an online server we started getting this error: Commit: Commit failed (details follow): File or directory 'x.php' is out of date; try updating resource out of date; try updating CHECKOUT of '/!svn/ver/491/x.php': 409 Conflict (http://svn.example.com) We are currently using SmartSVN 6.5 and we have also tested with RapidSVN & Syncro (but we can't use tortoise as we have a lot of Ubunutu users) at the begining I though this How do you fix an SVN 409 Conflict Error would help, but it didn't we are still facing the same error and it's even more absurd now. the main problem is that after you get the error, you can't shake it of. Updating doesn't solve, reverting doesn't solve. You are just stuck with the error. The only thing that could work is removing the file from SVN and adding your version but that would be against why we are using SVN in the first place This is our apache config (and yes autoversioning is ON) <Location /> DAV svn SVNPath /home/example/svn SVNAutoversioning on AuthType Basic AuthName "Access Restricted" AuthUserFile /home/example/svn-auth-file Require valid-user </Location> <Directory /> <Files ~ "^\.ht"> Order allow,deny Allow from all Satisfy All </Files> <Files ~ "^error_log"> Order allow,deny Allow from all Satisfy All </Files> </Directory> And here are some observation: We don't receive conflicts anymore, we just get this 409 conflict you can somehow avoid the error if you always update before committing When committing a modified file + a newly added file, you get the error. As if the added file incremented the version by one and then you are committing another file with a older version. Please advise, we are about to go insane

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  • MySQL Database Design with Internationalization

    - by Some name
    Hello, I'm going to start work on a medium sized application, and i'm planning it's db design. One thing that I'm not sure about is this. I will have many tables which will need internationalization, such as: "membership_options, gender_options, language_options etc" Each of these tables will share common i18n fields, like: "title, alternative_title, short_description, description" In your opinion which is the best way to do it? Have an i18n table with the same fields for each of the tables that will need them? or do something like: Membership table Gender table ---------------- -------------- id | created_at id | created_at 1 - 22.03.2001 1 - 14.08.2002 2 - 22.03.2001 2 - 14.08.2002 General translation table ------------------------- record_id | table_name | string_name | alternative_title| .... |id_language 1 - membership regular null 1 (english) 1 - membership normale null 2 (italian) 1 - gender man null 1(english) 1 -gender uomo null 2(italian) This would avoid me repeating something like: membership_translation table ----------------------------- membership_id | name | alternative_title | id_lang 1 regular null 1 1 normale null 2 gender_translation table ----------------------------- gender_id | name | alternative_title | id_lang 1 man null 1 1 uomo null 2 and so on, so i would probably reduce the number of db tables, but i'm not sure about performance.I'm not much of a DB designer, so please let me know.

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  • C++: parsing with simple regular expression or shoud I use sscanf?

    - by Helltone
    I need to parse a string like func1(arg1, arg2); func2(arg3, arg4);. It's not a very complex parsing problem, so I would prefer to avoid resorting to flex/bison or similar utilities. My first approch was to try to use POSIX C regcomp/regexec or Boost implementation of C++ std::regex. I wrote the following regular expression, which does not work (I'll explain why further on). "^" "[ ;\t\n]*" "(" // (1) identifier "[a-zA-Z_][a-zA-Z0-9_]*" ")" "[ \t\n]*" "(" // (2) non-marking "\[" "(" // (3) non-marking "[ \t]*" "(" // (4..n-1) argument "[a-zA-Z0-9_]+" ")" "[ \t\n]*" "," ")*" "[ \t\n]*" "(" // (n) last argument "[a-zA-Z0-9_]+" ")" "]" ")?" "[ \t\n]*" ";" Note that the group 1 captures the identifier and groups 4..n-1 are intended to capture arguments except the last, which is captured by group n. When I apply this regex to, say func(arg1, arg2, arg3) the result I get is an array {func, arg2, arg3}. This is wrong because arg1 is not in it! The problem is that in the standard regex libraries, submarkings only capture the last match. In other words, if you have for instance the regex "((a*|b*))*" applied on "babb", the results of the inner match will be bb and all previous captures will have been forgotten. Another thing that annoys me here is that in case of error there is no way to know which character was not recognized as these functions provide very little information about the state of the parser when the input is rejected. So I don't know if I'm missing something here... In this case should I use sscanf or similar instead? Note that I prefer to use C/C++ standard libraries (and maybe boost).

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  • Immutable classes in C++

    - by ereOn
    Hi, In one of my projects, I have some classes that represent entities that cannot change once created, aka. immutable classes. Example : A class RSAKey that represent a RSA key which only has const methods. There is no point changing the existing instance: if you need another one, you just create one. My objects sometimes are heavy and I enforced the use of smart pointers to avoid copy. So far, I have the following pattern for my classes: class RSAKey : public boost::noncopyable, public boost::enable_shared_from_this<RSAKey> { public: /** * \brief Some factory. * \param member A member value. * \return An instance. */ static boost::shared_ptr<const RSAKey> createFromMember(int member); /** * \brief Get a member. * \return The member. */ int getMember() const; private: /** * \brief Constructor. * \param member A member. */ RSAKey(int member); /** * \brief Member. */ const int m_member; }; So you can only get a pointer (well, a smart pointer) to a const RSAKey. To me, it makes sense, because having a non-const reference to the instance is useless (it only has const methods). Do you guys see any issue regarding this pattern ? Are immutable classes something common in C++ or did I just created a monster ? Thank you for your advices !

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  • How to overcome the programmer's block ?

    - by Nicolas Dorier
    How do you do when, during the development of your application, you can't decide yourself what to do next. You have no problem technically speaking, you have no problem to write clean code BUT you have a problem to decide yourself on what to code now. And you spend time thinking and thinking again on your design, in the car, in the shower, and you cannot write a single line of code... I think we call this "analysis paralysis". I hate being in this state ! How can you avoid this ? How do you do to not fall in this state ? I think this occurs when we are writting a big chunk of code with no visible improvement, but I'm not sure... UPDATE Like some of you said, this problem is also what we call the "programmer's block" (analogy with the writer's block). Doing some TDD doesn't help because I'm stuck, I can't decide myself what class to code, what methods to put inside (even a name of method). Though I admit that it helps to break a big chunk of code into smaller ones. Like Talesh said my head becomes full of "what-if".

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  • Achieving Thread-Safety

    - by Smasher
    Question How can I make sure my application is thread-safe? Are their any common practices, testing methods, things to avoid, things to look for? Background I'm currently developing a server application that performs a number of background tasks in different threads and communicates with clients using Indy (using another bunch of automatically generated threads for the communication). Since the application should be highly availabe, a program crash is a very bad thing and I want to make sure that the application is thread-safe. No matter what, from time to time I discover a piece of code that throws an exception that never occured before and in most cases I realize that it is some kind of synchronization bug, where I forgot to synchronize my objects properly. Hence my question concerning best practices, testing of thread-safety and things like that. mghie: Thanks for the answer! I should perhaps be a little bit more precise. Just to be clear, I know about the principles of multithreading, I use synchronization (monitors) throughout my program and I know how to differentiate threading problems from other implementation problems. But nevertheless, I keep forgetting to add proper synchronization from time to time. Just to give an example, I used the RTL sort function in my code. Looked something like FKeyList.Sort (CompareKeysFunc); Turns out, that I had to synchronize FKeyList while sorting. It just don't came to my mind when initially writing that simple line of code. It's these thins I wanna talk about. What are the places where one easily forgets to add synchronization code? How do YOU make sure that you added sync code in all important places?

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  • Trouble creating a SQL query

    - by JoBu1324
    I've been thinking about how to compose this SQL query for a while now, but after thinking about it for a few hours I thought I'd ask the SO community to see if they have any ideas. Here is a mock up of the relevant portion of the tables: contracts id date ar (yes/no) term payments contract_id payment_date The object of the query is to determine, per month, how many payments we expect, vs how many payments we received. conditions for expecting a payment Expected payments begin on contracts.term months after contracts.date, if contracts.ar is "yes". Payments continue to be expected until the month after the first missed payment. There is one other complication to this: payments might be late, but they need to show up as if they were paid on the date expected. The data is all there, but I've been having trouble wrapping my head around the SQL query. I am not an SQL guru - I merely have a decent amount of experience handling simpler queries. I'd like to avoid filtering the results in code, if possible - but without your help that may be what I have to do. Expected Output Month Expected Payments Received Payments January 500 450 February 498 478 March 234 211 April 987 789 ... SQL Fiddle I've created an SQL Fiddle: http://sqlfiddle.com/#!2/a2c3f/2

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  • Block facebook from my website

    - by Joseph Szymborski
    I have a secure link direction service I'm running (expiringlinks.co). If I change the headers in php to redirect my visitors, then facebook is able to show a preview of the website I'm redirecting to when users send links to one another via facebook. I wish to avoid this. Right now, I'm using an AJAX call to get the URL and javascript to redirect, but it's causing problems for users who don't use javascript. Here are a number of ways I'd like to block facebook, but I can't seem to get working: I've tried blocking the facebook bot (facebookexternalhit/1.0 and facebookexternalhit/1.1) but it's not working, I don't think they're using them for this functionality. I'm thinking of blocking the facebook IP addresses, but I can't find all of them, and I don't think it'll work unless I get all of them. I've thought of using a CAPTCHA or even a button, but I can't bring myself to do that to my visitors. Not to mention I don't think anyone would use the site. I've searched the facebook docs for meta tags that would "opt-me out", but haven't found one, and doubt that I would trust it if I had. Any creative ideas or any idea how to implement the ones above? Thank you so much in advance!

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  • Testing approach for multi-threaded software

    - by Shane MacLaughlin
    I have a piece of mature geospatial software that has recently had areas rewritten to take better advantage of the multiple processors available in modern PCs. Specifically, display, GUI, spatial searching, and main processing have all been hived off to seperate threads. The software has a pretty sizeable GUI automation suite for functional regression, and another smaller one for performance regression. While all automated tests are passing, I'm not convinced that they provide nearly enough coverage in terms of finding bugs relating race conditions, deadlocks, and other nasties associated with multi-threading. What techniques would you use to see if such bugs exist? What techniques would you advocate for rooting them out, assuming there are some in there to root out? What I'm doing so far is running the GUI functional automation on the app running under a debugger, such that I can break out of deadlocks and catch crashes, and plan to make a bounds checker build and repeat the tests against that version. I've also carried out a static analysis of the source via PC-Lint with the hope of locating potential dead locks, but not had any worthwhile results. The application is C++, MFC, mulitple document/view, with a number of threads per doc. The locking mechanism I'm using is based on an object that includes a pointer to a CMutex, which is locked in the ctor and freed in the dtor. I use local variables of this object to lock various bits of code as required, and my mutex has a time out that fires my a warning if the timeout is reached. I avoid locking where possible, using resource copies where possible instead. What other tests would you carry out?

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  • Passing information safely between Wicket and Hibernate in long running conversations

    - by Peter Tillemans
    We are using Wicket with Hibernate in the background. As part of out UI we have quite long running conversations spanning multiple requests before the updated information is written back to the database. To avoid getting hibernate errors with detached objects we are now using value objects to transfer info from the service layer to Wicket. However we now end up with an explosion of almost the same objects : e.g. Answer (mapped entity saved in hibernate) AnswerVO (immutable value object) AnswerModel (A mutable bean in the session domain) IModel wrapped Wicket Model and usually this gets wrapped in a CompoundPropertyModel This plumbing becomes exponentially worse when collections to other objects are involved in the objects. There has to be a better way to organize this. Can anyone share tips to make this less onerous? Maybe make the value objects mutable so we can remove the need for a seaprate backing bean in Wicket? Use the entity beans but absolutely make dead-certain they are detached from hibernate. (easier said than done)? Some other tricks or patterns?

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  • Domain model for an optional many-many relationship

    - by Greg
    Let's say I'm modeling phone numbers. I have one entity for PhoneNumber, and one for Person. There's a link table that expresses the link (if any) between the PhoneNumber and Person. The link table also has a field for DisplayOrder. When accessing my domain model, I have several Use Cases for viewing a Person. I can look at them without any PhoneNumber information. I can look at them for a specific PhoneNumber. I can look at them and all of their current (or past) PhoneNumbers. I'm trying to model Person, not only for the standard CRUD operations, but for the (un)assignment of PhoneNumbers to a Person. I'm having trouble expressing the relationship between the two, especially with respects to the DisplayOrder property. I can think of several solutions but I'm not sure of which (if any) would be best. A PhoneNumberPerson class that has a Person and PhoneNumber property (most closely resembles database design) A PhoneCarryingPerson class that inherits from Person and has a PhoneNumber property. A PhoneNumber and/or PhoneNumbers property on Person (and vis-a-versa, a Person property on PhoneNumber) What would be a good way to model this that makes sense from a domain model perspective? How do I avoid misplaced properties (DisplayOrder on Person) or conditionally populated properties?

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  • The CLR has been unable to transition from COM context [...] for 60 seconds

    - by BlueRaja The Green Unicorn
    I am getting this error on code that used to work. I have not changed the code. Here is the full error: The CLR has been unable to transition from COM context 0x3322d98 to COM context 0x3322f08 for 60 seconds. The thread that owns the destination context/apartment is most likely either doing a non pumping wait or processing a very long running operation without pumping Windows messages. This situation generally has a negative performance impact and may even lead to the application becoming non responsive or memory usage accumulating continually over time. To avoid this problem, all single threaded apartment (STA) threads should use pumping wait primitives (such as CoWaitForMultipleHandles) and routinely pump messages during long running operations. And here is the code that caused it: var openFileDialog1 = new System.Windows.Forms.OpenFileDialog(); openFileDialog1.DefaultExt = "mdb"; openFileDialog1.Filter = "Management Database (manage.mdb)|manage.mdb"; //Stalls indefinitely on the following line, then gives the CLR error //one minute later. The dialog never opens. if(openFileDialog1.ShowDialog() == DialogResult.OK) { .... } Yes, I am sure the dialog is not open in the background, and no, I don't have any explicit COM code or unmanaged marshalling or multithreading. I have no idea why the OpenFileDialog won't open - any ideas?

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  • What makes good web form styling for business applications?

    - by ProfK
    Styling forms (form elements) is something that even Eric Meyer prefers to avoid. However, most business forms, and that is where styling is at issue; 'contact us' forms are easy to style, put window estate at a premium, with more 'document level' (e.g. invoice) fields, plus 'detail level' (e.g. invoice line) fields. Factors I often find at play are: At my minimum, at least two horizontally adjacent fieldsets are required. In applications vs. public web pages, fixed positioning vs fluid layout is often better. Quantity of content is important, vs. exaggerated readability. Users know the system, and cues etc. take a back seat. In light of factors like these, is there any available guidence for styling web form based applications? Are there any CSS or JavaScript frameworks that would make my quest to style these applications better than Visual Studios still pathetic 'Auto-format' (what drugs were those people on? I will never take them.)

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  • Initialize Static Array of Structs in C

    - by russell_h
    I implementing a card game in C. There are lots of types of cards and each has a bunch of information, including some actions that will need to be individually scripted associated with it. Given a struct like this (and I'm not certain I have the syntax right for the function pointer) struct CARD { int value; int cost; // This is a pointer to a function that carries out actions unique // to this card int (*do_actions) (struct GAME_STATE *state, int choice1, int choice2); }; I would like to initialize a static array of these, one for each card. I'm guessing this would look something like this int do_card0(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } int do_card1(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } extern static struct cardDefinitions[] = { {0, 1, do_card0}, {1, 3, do_card1} }; Will this work, and am I going about this the right way at all? I'm trying to avoid huge numbers of switch statements. Do I need to define the 'do_cardN' functions ahead of time, or is there some way to define them inline in the initialization of the struct (something like a lambda function in python)? I'll need read-only access to cardDefinitions from a different file - is 'extern static' correct for that? I know this is a lot of questions rolled into one but I'm really a bit vague about how to go about this. Thanks.

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  • (nested) user controls within a mvp pattern causing sporadic problems

    - by LLEA
    hi everyone, I have a serious problem with nested user controls (UCs) in WinForms while trying to implement the mvp pattern (passive view). The project consists of one model (designed as a singleton) and a set of different presenters with corresponding view interfaces. To avoid one huge view interface and therefore an overloaded main UI, I decided to make use of a set of different UCs. Each UC has one view interface and one presenter that can access the model. But there are nested UCs: meaning that one specialised UC implements sort of a basic UC. The main UI just represents a container for all those UCs. So far, so good (if not, please ask)?! There are two problems that I am facing now (but I guess both are of the same origin): From time to time it is not possible anymore to load the UCs and test them within the Visual Studio 2008 User Control Test Container. The error message just says that a project with an output type of class library cannot be started directly etc. I can "handle" that by unloading all UC projects and reloading them afterwards. (I guess the references to all mvp components and other UCs are then updated). Assuming that the implementation of my mvp pattern is okay and all those UCs are testable within the VS Test Container at a certain time - there is the biggest problem still left: I am not able to add any UC (even the basic and unnested ones) to a simple Form (UI). The error message: error message.jpg Could it be that my basic UC causes all these Problems?! It consists of two simple ComboBoxes and implements a basic presenter and basic view interface. Whenever I add this UC to a different UC the VS designer adds two references to the public getter methods of the UC as resources. I then manually remove those resources from the resx-file and commend the corresponding lines in the designer file. thx in advance

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  • Why does Android allocate more memory than needed when loading images

    - by Simon
    Folks, I don't think that this is a duplicate and is NOT one of those how do I avoid OOMs questions. This is a genuine quest for knowledge so hold off on those down votes please... Imagine I have a JPEG of 500x500 pixels. I load it as ARGB_8888 which is as "bad as it gets". I would expect Android to allocate 500x500x4 bytes = a little under 1MB however, look at a heap dump and you will see that Android allocates significantly more, often factors of 5-10 times greater. You frequently see questions on here about OOMS where the stack trace shows a heap request of say 15MB and it is ALWAYS much larger than is required simply to hold the bytes of the image. The OP usually catches some downvotes then is bombarded with stock answers and comments about using less memory (thanks Romain!) and in scaling. I think there is more than meets the eye here. Anybody know why this is? If there is no apparent answer, I will put together an SSCCE if it helps. PS. I assume that JPEG vs PNG etc is irrelevant since we're talking about the memory usage of the backing bitmap which is simply x times y times BPP - or am I being slow?

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  • How can I find out if the MainActivity is being paused from my Java class?

    - by quinestor
    I am using motion sensor detection in my application. My design is this: a class gets the sensor services references from the main activity and then it implements SensorEventListener. That is, the MainActivity does not listen for sensor event changes: public void onCreate(Bundle savedInstanceState) { // ... code mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE); mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER); // The following is my java class, it does not extends any android fragment/activty mShakeUtil = new ShakeUtil(mSensorManager,mAccelerometer,this); // ..more code.. } I can't redesign ShakeUtil so it is a fragment nor activity, unfortunately. Now to illustrate the problem consider: MainActivity is on its way to be destroyed/paused. I.e screen rotation ShakeUtil's onSensorChanged(SensorEvent event) gets called in the process.. One of the things that happen inside onSensorChanged is a dialog interaction, which gives the error: java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState When the previous happens between MainActivity's onSaveInstanceState and onPause. I know this can be prevented if I successfully detect that MainActivity is being pause in ShakeUtil. How can I detect that MainActivity is being paused or onSaveInstanceState was called from ShakeUtil? Alternatively, how can I avoid this issue without making Shakeutil extend activity? So far I have tried with flag variables but that isn't good enough, I guess these are not atomic operations. I tried using Activity's isChangingConfigurations(), but I get an undocummented "NoSuchMethodFound" error.. I am unregistering the sensors by calling ShakeUtil when onPause in main ACtivity

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