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  • web application or wep portal

    - by klo
    as title said differences between those 2. I read all the definition and some articles, but I need information about some other aspects. Here is the thing. We want to build a web site that will contain: site, database, uploads, numerous background services that would have to collect information from uploads and from some other sites, parse them etc...I doubt that there are portlets that fits our specific need so we will have to make them our self. So, questions: 1. Deployment ( and difference in cost if possible), is deploying portals much more easier then web app ( java or .net) 2. Server load. Does portal consume much of server power ( and can you strip portal of thing that you do not use) 3. Implementation and developing of portlets. Can u make all the things that you could have done in java or .net? 4. General thoughts of when to use portals and when classic web app. Tnx all in advence...

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  • Mac: How to create a .app from a Mono application

    - by Svish
    I have downloaded the zip version of KeePass. To run it I have to open the Terminal, go to wherever I unzipped it and run mono KeePass.exe. Is there someway I can take all the files in that zip file and that command and bundle them up so I get a KeePass.app I can stick in my Applications folder that can more easily be run?

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  • Windows 7 - problems launching default application

    - by Chris W
    Just built up a new W7 PC. I've noticed some strange issues with launching default applications. I've got Visual Studio & SQL Server Management Studio set run as administrator when launched. If i double click a .sql file SSMS opens ok but the file itself does not get loaded. If I do the same with a .sln then I get nothing at all from Visual Studio. For the latter I presume the UAC prompt is hidden somewhere waiting for me to say it's ok to launch the app but i've no idea what's happening with SSMS. Is this a W7 bug or are there some settings somewhere that I can tweak to improve this behaviour?

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  • problem with launching application from other os on a multi boot system

    - by Nrew
    What do I do so that I could launch firefox on windows 7 if it is installed on windows xp. I tried going to the drive where it is installed. And launch firefox from there but the firefox that is installed on windows 7 keeps on launching. I even changed the firefox.exe into something different and cleaned the registry using tune up utilites but still don't work. what do I do.

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  • application that copies all links in a web page

    - by user23950
    I have to download something and those 100+ links to megaupload are all in the same webpage. Do you know of a better way of copying those links instead of copy and pasting them one by one? So that it will accumulate all the links, or portion of the links that I want to get and copy it all in the clipboard then just paste it on the download manager. For windows xp or 7

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  • Singletons, thread safety and structuremap

    - by Ben
    Hi, Currently I have the following class: public class PluginManager { private static bool s_initialized; private static object s_lock = new object(); public static void Initialize() { if (!s_initialized) { lock (s_lock) { if (!s_initialized) { // initialize s_initialized = true; } } } } } The important thing here is that Initialize() should only be executed once whilst the application is running. I thought that I would refactor this into a singleton class since this would be more thread safe?: public sealed class PluginService { static PluginService() { } private static PluginService _instance = new PluginService(); public static PluginService Instance { get { return _instance; } } private bool s_initialized; public void Initialize() { if (!s_initialized) { // initialize s_initialized = true; } } } Question one, is it still necessary to have the lock here (I have removed it) since we will only ever be working on the same instance? Finally, I want to use DI and structure map to initialize my servcices so I have refactored as below: public interface IPluginService { void Initialize(); } public class NewPluginService : IPluginService { private bool s_initialized; public void Initialize() { if (!s_initialized) { // initialize s_initialized = true; } } } And in my registry: ForRequestedType<IPluginService>() .TheDefaultIsConcreteType<NewPluginService>().AsSingletons(); This works as expected (singleton returning true in the following code): var instance1 = ObjectFactory.GetInstance<IPluginService>(); var instance2 = ObjectFactory.GetInstance<IPluginService>(); bool singleton = (instance1 == instance2); So my next question, is the structure map solution as thread safe as the singleton class (second example). The only downside is that this would still allow NewPluginService to be instantiated directly (if not using structure map). Many thanks, Ben

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  • Sharing application link via the same application, iphone

    - by Nithin
    Possible duplicate: How can i give app store link in my apps before approving another apps linking to an app on the Itunes store How to link to apps on the app store Hi all, I'm a littile bit confused. I need to provide the download link of my application (the iTunes link) inside my application. ie when the user would like to invite others via mail or some other means, have to provide the application link too with that.Is there any way to provide that before submitting the application to apple. Or i need to use the link as an update after getting my application approved by apple?

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  • How to access web application class into silverlight application

    - by Srikanth
    Hi..I am beginner in silverlight..I have created a silverlight project. When a new silverlight project is created it is automatically creating a silverlight application and one web application. I have added a class in both applications. Now I want to access a method of web application class into silverlight application class. Is it possible? I have tried to add web application reference to silverlight but VS is not allowing. Is there any another way to do??

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  • Different Versions of an application in same java application server

    - by Cem
    Hi, We are utilizing citrix netscalar with more than 20 glassfish java application servers. Unfortunately we have to remove previous application before deploying a new version of it since we have same context for these two different application. This error-prone process leads some problems due to lack of attention in builds or other problems. In an urgent case, we simply want to redirect to all traffic to previous application. What is the best practice to run different version of an application in a substantial number of servers in same time? Thanks

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  • When should EntityManagerFactory instance be created/opened ?

    - by masato-san
    Ok, I read bunch of articles/examples how to write Entity Manager Factory in singleton. One of them easiest for me to understand a bit: http://javanotepad.blogspot.com/2007/05/jpa-entitymanagerfactory-in-web.html I learned that EntityManagerFactory (EMF) should only be created once preferably in application scope. And also make sure to close the EMF once it's used (?) So I wrote EMF helper class for business methods to use: public class EmProvider { private static final String DB_PU = "KogaAlphaPU"; public static final boolean DEBUG = true; private static final EmProvider singleton = new EmProvider(); private EntityManagerFactory emf; private EmProvider() {} public static EmProvider getInstance() { return singleton; } public EntityManagerFactory getEntityManagerFactory() { if(emf == null) { emf = Persistence.createEntityManagerFactory(DB_PU); } if(DEBUG) { System.out.println("factory created on: " + new Date()); } return emf; } public void closeEmf() { if(emf.isOpen() || emf != null) { emf.close(); } emf = null; if(DEBUG) { System.out.println("EMF closed at: " + new Date()); } } }//end class And my method using EmProvider: public String foo() { EntityManager em = null; List<Object[]> out = null; try { em = EmProvider.getInstance().getEntityManagerFactory().createEntityManager(); Query query = em.createNativeQuery(JPQL_JOIN); //just some random query out = query.getResultList(); } catch(Exception e) { //handle error.... } finally { if(em != null) { em.close(); //make sure to close EntityManager } } I made sure to close EntityManager (em) within method level as suggested. But when should EntityManagerFactory be closed then? And why EMF has to be singleton so bad??? I read about concurrency issues but as I am not experienced multi-thread-grammer, I can't really be clear on this idea.

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  • Purpose of singletons in programming

    - by thecoshman
    This is admittedly a rather loose question. My current understanding of singletons is that they are a class that you set up in such a way that only one instance is ever created. This sounds a lot like a static class to me. The main differnce being that with a static class you don't / can't instance it, you just use it such as Math.pi(). With a singletong class, you would still need to do something like singleton mySingleton = new singleton(); mysingleton.set_name("foo"); singleton otherSingleton = new singleton(); // correct me if i am wrong, but mysingleton == othersingleton right now, yes? // this the following should happen? otherSingleston.set_name("bar"); mysingleton.report_name(); // will output "bar" won't it? Please note, I am asking this language independently, more about the concept. So I am not so worried about actually how to coed such a class, but more why you would wan't to and what thing you would need to consider.

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  • My Delphi 7 application halts on Application.Initialize and does not return to next line

    - by m-abdi
    I have created an application on Delphi 7. my app had running fine since yesterday. I don't know what's happened yesterday which cause my application halts on Application.Initialize line in source code and does not return to next line when i trace the program. I can't run the created executable file from widows niether while the generated file does run on another machine correctly. here is the code where the compiler stops on it: program Info_Kiosk; uses SysUtils, Forms, ... (some other units) ; {$R *.res} begin Application.Initialize; Application.CreateForm(Tfrm_Main, frm_Main); any help would be appreciated

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  • Hosting and scaling of a facebook application on cloud?

    - by DhruvPathak
    We would be building a facebook application in django(Python), but still not sure of where to host it economically,and with a good provision to scale in case the app gets viral. Some details about the app: i) Would be HTML based like a website,using django as a framework. ii) 100K is the number of expected pageviews in a day,if the app is viral. iii) The users will not generate any media content,only some database data will be generated by them. It would be great if someone with more experience can guide on following points: A) Hosting on google app engine or Amazon EC2 or some other cloud like RackSpace : Preferable points found in AppEngine were ease of deployment,cost effectiveness and easy scaling. For EC2: Full hold of the virtual machine,Amazon NoSQL and RDMBS database services in case we decide to use them. B) Does backend technology affect monthly cost ? eg. would CPU and memory usage difference of Django over , for example , PHP framework like CodeIgnitor really make remarkable difference in running costs. ( Here is the article that triggered this thought process : http://journal.dedasys.com/2010/01/12/rough-estimates-of-the-dollar-cost-of-scaling-web-platforms-part-i#comments) C) Does something like Heroku , which provides additional services over Amazon EC2, prove to be better than raw cloud management ? It is not that we are trying for premature scaling, we just want to have a good start so that we are ready to handle unpredicted growth and scale.

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  • Hosting and scaling a Facebook application in the cloud? [migrated]

    - by DhruvPathak
    We would be building a Facebook application in Django (Python), but still not sure of where to host it economically, and with a good provision to scale in case the app gets viral. Some details about the app: Would be HTML based like a website,using django as a framework. 100K is the number of expected pageviews in a day, if the app is viral. The users will not generate any media content, only some database data will be generated by them. It would be great if someone with more experience can guide on following points: A) Hosting on Google app engine or Amazon EC2 or some other cloud like RackSpace : Preferable points found in AppEngine were ease of deployment, cost effectiveness and easy scaling. For EC2: Full hold of the virtual machine,Amazon NoSQL and RDMBS database services in case we decide to use them. B) Does backend technology affect monthly cost? eg. would CPU and memory usage difference of Django over , for example , PHP framework like CodeIgnitor really make remarkable difference in running costs. (Here is the article that triggered this thought process : http://journal.dedasys.com/2010/01/12/rough-estimates-of-the-dollar-cost-of-scaling-web-platforms-part-i#comments) C) Does something like Heroku , which provides additional services over Amazon EC2, prove to be better than raw cloud management? It is not that we are trying for premature scaling, we just want to have a good start so that we are ready to handle unpredicted growth and scale.

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  • Hosting and scaling a Facebook application in the cloud? [closed]

    - by DhruvPathak
    Possible Duplicate: How to find web hosting that meets my requirements? We would be building a Facebook application in Django (Python), but still not sure of where to host it economically, and with a good provision to scale in case the app gets viral. Some details about the app: Would be HTML based like a website,using django as a framework. 100K is the number of expected pageviews in a day, if the app is viral. The users will not generate any media content, only some database data will be generated by them. It would be great if someone with more experience can guide on following points: A) Hosting on Google app engine or Amazon EC2 or some other cloud like RackSpace : Preferable points found in AppEngine were ease of deployment, cost effectiveness and easy scaling. For EC2: Full hold of the virtual machine,Amazon NoSQL and RDMBS database services in case we decide to use them. B) Does backend technology affect monthly cost? eg. would CPU and memory usage difference of Django over , for example , PHP framework like CodeIgnitor really make remarkable difference in running costs. (Here is the article that triggered this thought process : http://journal.dedasys.com/2010/01/12/rough-estimates-of-the-dollar-cost-of-scaling-web-platforms-part-i#comments) C) Does something like Heroku , which provides additional services over Amazon EC2, prove to be better than raw cloud management? It is not that we are trying for premature scaling, we just want to have a good start so that we are ready to handle unpredicted growth and scale.

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  • Developing a Cost Model for Cloud Applications

    - by BuckWoody
    Note - please pay attention to the date of this post. As much as I attempt to make the information below accurate, the nature of distributed computing means that components, units and pricing will change over time. The definitive costs for Microsoft Windows Azure and SQL Azure are located here, and are more accurate than anything you will see in this post: http://www.microsoft.com/windowsazure/offers/  When writing software that is run on a Platform-as-a-Service (PaaS) offering like Windows Azure / SQL Azure, one of the questions you must answer is how much the system will cost. I will not discuss the comparisons between on-premise costs (which are nigh impossible to calculate accurately) versus cloud costs, but instead focus on creating a general model for estimating costs for a given application. You should be aware that there are (at this writing) two billing mechanisms for Windows and SQL Azure: “Pay-as-you-go” or consumption, and “Subscription” or commitment. Conceptually, you can consider the former a pay-as-you-go cell phone plan, where you pay by the unit used (at a slightly higher rate) and the latter as a standard cell phone plan where you commit to a contract and thus pay lower rates. In this post I’ll stick with the pay-as-you-go mechanism for simplicity, which should be the maximum cost you would pay. From there you may be able to get a lower cost if you use the other mechanism. In any case, the model you create should hold. Developing a good cost model is essential. As a developer or architect, you’ll most certainly be asked how much something will cost, and you need to have a reliable way to estimate that. Businesses and Organizations have been used to paying for servers, software licenses, and other infrastructure as an up-front cost, and power, people to the systems and so on as an ongoing (and sometimes not factored) cost. When presented with a new paradigm like distributed computing, they may not understand the true cost/value proposition, and that’s where the architect and developer can guide the conversation to make a choice based on features of the application versus the true costs. The two big buckets of use-types for these applications are customer-based and steady-state. In the customer-based use type, each successful use of the program results in a sale or income for your organization. Perhaps you’ve written an application that provides the spot-price of foo, and your customer pays for the use of that application. In that case, once you’ve estimated your cost for a successful traversal of the application, you can build that into the price you charge the user. It’s a standard restaurant model, where the price of the meal is determined by the cost of making it, plus any profit you can make. In the second use-type, the application will be used by a more-or-less constant number of processes or users and no direct revenue is attached to the system. A typical example is a customer-tracking system used by the employees within your company. In this case, the cost model is often created “in reverse” - meaning that you pilot the application, monitor the use (and costs) and that cost is held steady. This is where the comparison with an on-premise system becomes necessary, even though it is more difficult to estimate those on-premise true costs. For instance, do you know exactly how much cost the air conditioning is because you have a team of system administrators? This may sound trivial, but that, along with the insurance for the building, the wiring, and every other part of the system is in fact a cost to the business. There are three primary methods that I’ve been successful with in estimating the cost. None are perfect, all are demand-driven. The general process is to lay out a matrix of: components units cost per unit and then multiply that times the usage of the system, based on which components you use in the program. That sounds a bit simplistic, but using those metrics in a calculation becomes more detailed. In all of the methods that follow, you need to know your application. The components for a PaaS include computing instances, storage, transactions, bandwidth and in the case of SQL Azure, database size. In most cases, architects start with the first model and progress through the other methods to gain accuracy. Simple Estimation The simplest way to calculate costs is to architect the application (even UML or on-paper, no coding involved) and then estimate which of the components you’ll use, and how much of each will be used. Microsoft provides two tools to do this - one is a simple slider-application located here: http://www.microsoft.com/windowsazure/pricing-calculator/  The other is a tool you download to create an “Return on Investment” (ROI) spreadsheet, which has the advantage of leading you through various questions to estimate what you plan to use, located here: https://roianalyst.alinean.com/msft/AutoLogin.do?d=176318219048082115  You can also just create a spreadsheet yourself with a structure like this: Program Element Azure Component Unit of Measure Cost Per Unit Estimated Use of Component Total Cost Per Component Cumulative Cost               Of course, the consideration with this model is that it is difficult to predict a system that is not running or hasn’t even been developed. Which brings us to the next model type. Measure and Project A more accurate model is to actually write the code for the application, using the Software Development Kit (SDK) which can run entirely disconnected from Azure. The code should be instrumented to estimate the use of the application components, logging to a local file on the development system. A series of unit and integration tests should be run, which will create load on the test system. You can use standard development concepts to track this usage, and even use Windows Performance Monitor counters. The best place to start with this method is to use the Windows Azure Diagnostics subsystem in your code, which you can read more about here: http://blogs.msdn.com/b/sumitm/archive/2009/11/18/introducing-windows-azure-diagnostics.aspx This set of API’s greatly simplifies tracking the application, and in fact you can use this information for more than just a cost model. After you have the tracking logs, you can plug the numbers into ay of the tools above, which should give a representative cost or in some cases a unit cost. The consideration with this model is that the SDK fabric is not a one-to-one comparison with performance on the actual Windows Azure fabric. Those differences are usually smaller, but they do need to be considered. Also, you may not be able to accurately predict the load on the system, which might lead to an architectural change, which changes the model. This leads us to the next, most accurate method for a cost model. Sample and Estimate Using standard statistical and other predictive math, once the application is deployed you will get a bill each month from Microsoft for your Azure usage. The bill is quite detailed, and you can export the data from it to do analysis, and using methods like regression and so on project out into the future what the costs will be. I normally advise that the architect also extrapolate a unit cost from those metrics as well. This is the information that should be reported back to the executives that pay the bills: the past cost, future projected costs, and unit cost “per click” or “per transaction”, as your case warrants. The challenge here is in the model itself - statistical methods are not foolproof, and the larger the sample (in this case I recommend the entire population, not a smaller sample) is key. References and Tools Articles: http://blogs.msdn.com/b/patrick_butler_monterde/archive/2010/02/10/windows-azure-billing-overview.aspx http://technet.microsoft.com/en-us/magazine/gg213848.aspx http://blog.codingoutloud.com/2011/06/05/azure-faq-how-much-will-it-cost-me-to-run-my-application-on-windows-azure/ http://blogs.msdn.com/b/johnalioto/archive/2010/08/25/10054193.aspx http://geekswithblogs.net/iupdateable/archive/2010/02/08/qampa-how-can-i-calculate-the-tco-and-roi-when.aspx   Other Tools: http://cloud-assessment.com/ http://communities.quest.com/community/cloud_tools

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  • Get close window message in Hidden C# Console Application

    - by LexRema
    Hello everyone. I have a Windows Form that starts some console application in background(CreateNoWindow = rue,WindowStyle = ProcessWindowStyle.Hidden). Windows form gives me opportunity to stop the console application at any time. But I'd like to handle somehow the close message inside the console application. I tried to use hooking like: [DllImport("Kernel32")] public static extern bool SetConsoleCtrlHandler(HandlerRoutine handler, bool add); // A delegate type to be used as the handler routine // for SetConsoleCtrlHandler. public delegate bool HandlerRoutine(CtrlTypes ctrlType); // An enumerated type for the control messages // sent to the handler routine. public enum CtrlTypes { CTRL_C_EVENT = 0, CTRL_BREAK_EVENT, CTRL_CLOSE_EVENT, CTRL_LOGOFF_EVENT = 5, CTRL_SHUTDOWN_EVENT } private static bool ConsoleCtrlCheck(CtrlTypes ctrlType) { StaticLogger.Instance.DebugFormat("Main: ConsoleCtrlCheck: Got event {0}.", ctrlType); if (ctrlType == CtrlTypes.CTRL_CLOSE_EVENT) { // Handle close stuff } return true; } static int Main(string[] args) { // Subscribing HandlerRoutine hr = new HandlerRoutine(ConsoleCtrlCheck); SetConsoleCtrlHandler(hr, true); // Doing stuff } but I get the message inside ConsoleCtrlCheck only if the console window is created. But if window is hidden - I don't get any message. In my windows Form to close console application process I use proc.CloseMainWindow(); to send message to the console window. P.S. AppDomain.CurrentDomain.ProcessExit += CurrentDomain_ProcessExit; - also does not help Do you now other way to handle this situation? Thanks.

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  • cfml error with application.cfc page

    - by tibin mathew
    Hi, I have some problem with my cfml website. I have used the below code in application.cfc file to connect with the dsn. But when ever i put this in my server, i'm getting error. i cant browse even a single test.cfm page. Is there any mistake in that code , any syntax error or something like that, will it be some problem with the dsn <cfset this.name = "0307de6.netsolhost.com"> <cfset this.sessionmanagement = true> <cfset this.loginstorage="session"> <cfset this.sessiontimeout = CreateTimeSpan(0,0,30,0)> <cfset this.applicationtimeout = CreateTimeSpan(2,0,0,0)> <cffunction name="onApplicationStart"> <cfscript> application.DSN = "hirerodsn"; application.dbUserName = "myusr"; application.dbPassword = "myd69!"; </cfscript> </cffunction> <cffunction name="onRequestStart"> <cfscript> request.DSN = "hirerodsn"; request.dbUserName = "myusr"; request.dbPassword = "myd69!"; </cfscript> </cffunction> please anyone help me

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  • What java web application framework to use?

    - by frohiky
    One of the main products of my company is an Oracle Forms (and Reports) based application, that "needs" to be re-written in another technology. Why? Users want a more rich interface experience, and we want, preferably, to reduce costs with an open source application server. For this (HUGE) project, we intend to use a java web application framework, keep these points in mind: We have: hundreds of tables on our database (the ORM must be as flexible as possible); some logic which is (and will still be) based on PL/SQL procedures/functions/packages; a lot of CRUDs (the application itself is of an considerable size); a demand to work with/generate documents and workflows; an intranet based user environment; We want: to offer a RIA interface experience; use (if possible) an open source app server; a rapid (as possible) development framework; a somewhat mature framework with a "wise" roadmap (and a considerable community support); a MVC approach combined with JS or GWT widgets (e.g. Vaadin or SmartGWT); Well, in the past weeks I've read a lot of posts, Q&As on stackoverflow, and much more: Wicket, JSF, Tapestry, Grails, GWT, Struts2, Play, Spring, Seam, Echo, .... the list goes on! I've even researched about Alfresco..! The obvious question: Which one to use? At this time, any insight, recommendation, shared experience, advice will be more then welcome!

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  • WPF : Access Application Resources when not referencing Shell from App.xaml

    - by CF_Maintainer
    I am beginner in WPF. My App.xaml looks like below app.xaml <Application x:Class="ContactManager.App" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <Application.Resources> <Color x:Key="lightBlueColor">#FF145E9D</Color> <SolidColorBrush x:Key="lightBlueBrush" Color="{StaticResource lightBlueColor}" /> </Application.Resources> I do not set the startupuri since I want to a presenter first approach. I do the following in app.xaml.cs protected override void OnStartup(StartupEventArgs e) { base.OnStartup(e); var appPresenter = new ApplicationPresenter( new Shell(), new ContactRepository()); appPresenter.LaunchView(); } I have a usercontrol called "SearchBar.xaml" which references "lightBlueBrush" as a staticResource. When I try to open "Shell.xaml" in the designer it tells me : The "shell.xaml" cannot be loaded at design time because it says it could not create an instance of type "SearchBar.xaml". When I debugged the devenv.exe using another visual studio instance it tells me that it does not have access to the Brush I created in app.resources. If one is doing a Presenter first approach, how does one access resources? I had this working when the startupURI was "Shell.xaml" and the startup event was not present. Any clues/ideas/suggestions. I am just trying to understand. Everything works as expected when I run the application just not @ design time.

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  • Where to start with map application

    - by rfders
    Hi there, i'm trying to desing a new application which allow user see he/her current location on a custom map (office, university compus, etc). but actually i have a couple of question in my mind (i haven't designed this kind of application before). i'm wondering: How can i draw my own maps, what is the best option for it? there any format that i have to care of, there are any specification about it ? Once i have my custom map. how can i do to mapping a global position system with the local positions ? What are the tricks behing zoom on maps ? just differents layers with more or less informations and those layers changes on users demand ? If a whant to mark some specific points over the map, like a cafeteria, boss's office etc, how can i do that ? Sorry if my questions are too much generics and dumb, but i really need some clues about this topic because i don't have any idea how to design this kind of application as best as possible. and we don't whant to reinvent the wheel. I will appreciate any help that you can provide me in order to desing this application

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  • DI and Singleton Pattern in one implementation

    - by Tony
    I want to refactor some code using the Windsor IOC/DI framework, but my issue is that I have some Singleton classes and Factory pattern classes and I am not sure that one can implement a Singleton or Factory using DI. Has anyone any ideas if that is possible and how?

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  • Refactoring Singleton Overuse

    - by drharris
    Today I had an epiphany, and it was that I was doing everything wrong. Some history: I inherited a C# application, which was really just a collection of static methods, a completely procedural mess of C# code. I refactored this the best I knew at the time, bringing in lots of post-college OOP knowledge. To make a long story short, many of the entities in code have turned out to be Singletons. Today I realized I needed 3 new classes, which would each follow the same Singleton pattern to match the rest of the software. If I keep tumbling down this slippery slope, eventually every class in my application will be Singleton, which will really be no logically different from the original group of static methods. I need help on rethinking this. I know about Dependency Injection, and that would generally be the strategy to use in breaking the Singleton curse. However, I have a few specific questions related to this refactoring, and all about best practices for doing so. How acceptable is the use of static variables to encapsulate configuration information? I have a brain block on using static, and I think it is due to an early OO class in college where the professor said static was bad. But, should I have to reconfigure the class every time I access it? When accessing hardware, is it ok to leave a static pointer to the addresses and variables needed, or should I continually perform Open() and Close() operations? Right now I have a single method acting as the controller. Specifically, I continually poll several external instruments (via hardware drivers) for data. Should this type of controller be the way to go, or should I spawn separate threads for each instrument at the program's startup? If the latter, how do I make this object oriented? Should I create classes called InstrumentAListener and InstrumentBListener? Or is there some standard way to approach this? Is there a better way to do global configuration? Right now I simply have Configuration.Instance.Foo sprinkled liberally throughout the code. Almost every class uses it, so perhaps keeping it as a Singleton makes sense. Any thoughts? A lot of my classes are things like SerialPortWriter or DataFileWriter, which must sit around waiting for this data to stream in. Since they are active the entire time, how should I arrange these in order to listen for the events generated when data comes in? Any other resources, books, or comments about how to get away from Singletons and other pattern overuse would be helpful.

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  • example for Singleton pattern

    - by JavaUser
    Hi, Please give me a real time example for singleton pattern . Different threads accessing a shared file is singleton or not ? Since each thread access the same instance of the file not individual instances of their own .

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