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  • Reducing load time, or making the user think the load time is less

    - by Malfist
    I've been working on a website, and we've managed to reduce the total content for a page load from 13.7MiB's to 2.4, but the page still takes forever to load. It's a joomla site (ick), and it has a lot of redundant DOM elements (2000+ for the home page), and make 60+ HttpRequest's per page load, counting all the css, js, and image requests. Unlike drupal, joomla won't merge them all on the fly, and they have to be kept separate or else the joomla components will go nuts. What can I do to improve load time? Things I've done: Added colors to dom elements that have large images as their background so the color is loaded, then the image Reduced excessively large images to much smaller file sizes Reduced DOM elements to ~2000, from ~5000 Loading CSS at the start of the page, and javascript at the end Not totally possible, joomla injects it's own javascript and css and it does it at the header, always. Minified most javascript Setup caching and gziping on server Uncached size 2.4MB, cached is ~300KB, but even with so many dom elements, the page takes a good bit of time to render. What more can I do to improve the load time?

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  • Performance - User defined query / filter to search data

    - by Cagatay Kalan
    What is the best way to design a system where users can create their own criterias to search data ? By "design" i mean, data storage, data access layer and search structure. We will actually refactor an existing application which is written in C# and ASP .NET and we don't want to change the infrastructure. Our main issue is performance and we use MSSQL and DevExpress to build queries. Some queries run in 4-5 minutes and all the columns included in the queries have indexes. When i check queries, i see that DevExpress builds too many "exists" clauses and i'm not happy with that because i have doubts that some of these queries skip some indexes. What may be the alternatives to DevExpress? NHibernate or Entity Framework? Can we build dynamic criteria system and store these to database in both of them ? And also do we need any alternative storage like a lucene index or OLAP database?

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  • Consing lists with user-defined type in Haskell

    - by user1319603
    I have this type I defined myself: data Item = Book String String String Int -- Title, Author, Year, Qty | Movie String String String Int -- Title, Director, Year, Qty | CD String String String Int deriving Show -- Title, Artist, Year, Qty I've created an empty list all_Items = [] With the following function I am trying to insert a new book of type Item (Book) into the all_Items addBook all_Items = do putStrLn "Enter the title of the book" tit <- getLine putStrLn "Enter the author of the book" aut <- getLine putStrLn "Enter the year this book was published" yr <- getLine putStrLn "Enter quantity of copies for this item in the inventory" qty <- getLine Book tit aut yr (read qty::Int):all_Items return(all_Items) I however am receiving this error: Couldn't match expected type `IO a0' with actual type `[a1]' The error points to the line where I am using the consing operator to add the new book to the list. I can gather that it is a type error but I can't figure out what it is that I am doing wrong and how to fix it. Thanks in Advance!

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  • How to get user feedback?

    - by kost
    Hi, I am developing a web application, which is still in initial stages.I have put it on web for public to use.Should I use uservoice for feedback(free account)? What are the alternatives?

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  • User to kernel mode big picture?

    - by fsdfa
    I've to implement a char device, a LKM. I know some basics about OS, but I feel I don't have the big picture. In a C programm, when I call a syscall what I think it happens is that the CPU is changed to ring0, then goes to the syscall vector and jumps to a kernel memmory space function that handle it. (I think that it does int 0x80 and in eax is the offset of the syscall vector, not sure). Then, I'm in the syscall itself, but I guess that for the kernel is the same process that was before, only that it is in kernel mode, I mean the current PCB is the process that called the syscall. So far... so good?, correct me if something is wrong. Others questions... how can I write/read in process memory?. If in the syscall handler I refer to address, say, 0xbfffffff. What it means that address? physical one? Some virtual kernel one?

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  • GUI Freezes and Output to JTextField from user input

    - by user2929005
    I am having I hope only two issues currently. I have had help on this on a previous question that I have asked but now I am running into different issues. My current issues now is that I need to print out into a JTextField a sorted array. I do not have questions about how to sort the array I just would like help on how to get the array to print to the JTextField when the Bubble Sort button is pressed. Currently when I press the button it freezes. It freezes at this line. list.add(Integer.valueOf(input.nextInt())); please help Thank you. import java.awt.EventQueue; import javax.swing.*; import java.awt.event.*; import java.util.*; public class Sorting { private JFrame frame; private JTextArea inputArea; private JTextField outputArea; ArrayList<Integer> list = new ArrayList<Integer>(); Scanner input = new Scanner(System.in); /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { Sorting window = new Sorting(); window.frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the application. */ public Sorting() { initialize(); } /** * Initialize the contents of the frame. */ private void initialize() { frame = new JFrame(); frame.setBounds(100, 100, 450, 300); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setTitle("Sorting"); frame.getContentPane().setLayout(null); JButton bubbleButton = new JButton("Bubble Sort"); bubbleButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { list.add(Integer.valueOf(input.nextInt())); // for(int i = 0; i < list.size(); i++){ // // } } }); bubbleButton.setBounds(10, 211, 114, 23); frame.getContentPane().add(bubbleButton); JButton mergeButton = new JButton("Merge Sort"); mergeButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { } }); mergeButton.setBounds(305, 211, 114, 23); frame.getContentPane().add(mergeButton); JButton quickButton = new JButton("Quick Sort"); quickButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { } }); quickButton.setBounds(163, 211, 114, 23); frame.getContentPane().add(quickButton); inputArea = new JTextArea(); inputArea.setBounds(10, 36, 414, 51); frame.getContentPane().add(inputArea); outputArea = new JTextField(); outputArea.setEditable(false); outputArea.setBounds(10, 98, 414, 59); frame.getContentPane().add(outputArea); outputArea.setColumns(10); JLabel label = new JLabel("Please Enter 5 Numbers"); label.setHorizontalAlignment(SwingConstants.CENTER); label.setBounds(10, 11, 414, 14); frame.getContentPane().add(label); } }

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  • Couldn't run loadjava on user schema to load dbwsclientws.jar dbwsclientdb102.jar

    - by padmaja
    I am trying to load oracle webservice client jars to my schema. I did set the PATH to inlcude: /u01/app/oracle/product/10.2.0/db_1/bin When I try to run loadjava as "loadjava -u myschema/myscehmapwd -r -v -f -genmissing dbwsclientws.jar dbwsclientdb102.jar" I am getting error: Exception in thread "main" java.lang.NoClassDefFoundError: oracle/aurora/server/tools/loadjava/LoadJavaMain. Does it mean that jvm is not setup on the box? How can I check if the jvm is enabled or not? I am running it on Oracle 10g in UNIX environment. Any help with the issue is greatly appreciated.

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  • user interface pattern for associating single or many objects to an entity

    - by Samuel
    Need suggestions on implementing associating single or many objects to an entity. All soccer team players are registered individually (e.g. they are part of 'players' table) A soccer team has many players. The click sequence is like this:- a] Soccer team owner provides a name and brief description of the soccer team. b] Now it wants to add players to this team. c] You have the following button 'Add players to team' which lets you navigate to the 'View Players' page and lets you multi select users from there. Assuming this is a paginated list of players, how do you handle the following:- Do you provide a check box against each player and let the manager do a multi selection. If you need to add more players, it doesn't make sense to show the players who have been already added to the team. Do you mark those entries as not selectable or you would adding showing these entries. If you need to filter, do you provide search filters at the top of this page. Am looking for ideas on how to implement this or sites which have already done something similar.

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  • User Interface Diagram That is always reachable

    - by Fosa
    If you have to build a flow of a Use-case by drawing each Interface Diagram. Then you would start with a Diagram like say "login". But after the login page, no mather wich page you choose except the "logout" page, you always have your navigation bar right ? So all the options in the navigation bar? Like account page , personal page, etc... Do you have to make sure in your flow that in every diagram there is acces to the "accountpage" diagram ? Or do they have an other solution for that ? Thanx in advance

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  • tools for creating user-friendly command-line prompt?

    - by davka
    I notice that some programs (e.g. sqlite, mysql client) provide a command-line prompt that is very similar in capabilities to the bash's, including: line editing with left and right arrows, delete, insert, ^K, etc. history browsing with up and down arrows ^R for reverse i-search in command history which make me think that they are using the same toolset for this. I'd like to create a prompt with similar capabilities in my program, which tools can I use? I prefer it to have the same functionality as in bash, so that the users would be familiar with it.

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  • Getting Error whileInitializing entities [closed]

    - by R76
    I am new'b as WPF Dev. I am developing Window application in WPF using mvvmlight framework. I have created database in Sqlserver compact 4.0. I have made a Ado.net Entity Data Model. When I trying to initialize the Entity object in service it throws the error like: Error 'The invocation of the constructor on type 'PointOfSale.ViewModels.ProductsViewModel' that matches the specified binding constraints threw an exception.' Line number '7' and line position '10'. stack Trace at System.Windows.Markup.XamlReader.RewrapException(Exception e, IXamlLineInfo lineInfo, Uri baseUri) at System.Windows.Markup.WpfXamlLoader.Load(XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri) at System.Windows.Markup.WpfXamlLoader.LoadBaml(XamlReader xamlReader, Boolean skipJournaledProperties, Object rootObject, XamlAccessLevel accessLevel, Uri baseUri) at System.Windows.Markup.XamlReader.LoadBaml(Stream stream, ParserContext parserContext, Object parent, Boolean closeStream) at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator) at PointOfSale.MainWindow.InitializeComponent() in e:\VarniApplication\PointOfSale\PointOfSale\MainWindow.xaml:line 1 at PointOfSale.MainWindow..ctor() in E:\VarniApplication\PointOfSale\PointOfSale\MainWindow.xaml.cs:line 27 Inner Exception {"Unable to load the specified metadata resource."} My code: xyzEntities entites; public ctor() { entites = new xyzEntities(); //This line throws an error } I have installed sql server compact 4.0 from web installer 3.0. and added the sql server compact toolbox from the extension manager. Tell me if I am missing something to install or missing something to write code.

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  • Shorter GUIDs than hashing a user id?

    - by Alex Mcp
    I'm wondering how Instapaper (bookmarklet that saves text) might generate URLs for their bookmarklet. Mine has a script src of something similar to www.instapaper.com/j/AnJHrfoDTRia The quality of these URLs is that they need to never collide, and not be really guessable (so other people can't save to your account). I know a simple approach might be to MD5 their email address (presumed to have been checked on signup for uniqueness), but then I'd end up with a super long string. This isn't a huge issue, but I'm wondering what techniques there are for shorter GUIDs that won't collide too often (this is obviously the tradeoff, but 12 characters above is pretty short in my opinion)

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  • Switch User in RedHat like XP [closed]

    - by rd42
    In our cluster, RedHat4 & 5 machines, if someone locks the computer and walks away no body can use it. Is there a feature in RedHat5, Gnome, KDE etc that would allow for the option of switching users at the lock screen, so more than one person can be logged in? Thanks, rd42

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  • User Inactivity Logout PHP

    - by user342391
    I want my users to be logged out automatically after X minutes of inactivity. I also want to have all sessions destroyed. How can this be done? How can I check for inactivity then perform a function to log them out???

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  • c# user notification while waiting

    - by user315445
    Hi, I am writing a simple win forms app in C#. There is a method call in my method which loads files but is taking a while to respond. Below is the method call Directory.GetFiles(selectedFolder, "*.xml", SearchOption.AllDirectories); I want to notify this to users. Is there a way to show them that file loading is in progress? I want a simplest way. I suppose Splash screen is too costly for my app. Thanks, Sid

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  • Why is the "Standard Account" option disabled (grayed-out)

    - by Clayton Hughes
    I just installed Win7 64bit on a new hard drive, and I created a user account through the OOBE. I want to make my user account a standard user. However, if I go into "User Accounts" and select "Change my account type", the standard user option is greyed out--this account apparently has to be an administrator. I thought maybe it was the only admin account on the machine, so I tried to create a new user account named "Administrator", but was told I couldn't, because one already exists. What gives? What do I have to do to run as a standard user?

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  • LAMP: How do I set up http://myservername.com/~user access?

    - by Travesty3
    Been trying to Google this, but I can't figure out good search terms to find any info about what I need, since I don't really know what it's called. I'm pretty much being thrown to the wolves to figure out how to set up a LAMP server. We had someone who knew how to do it, he set one up and then quit. It was set up so that when I went to "http://{myservername}.com/~travis" it showed the contents of my /home/travis/public_html folder. This worked fine, then we lost power and the server restarted (I know, battery backup, but this is a dev server in a dev building so it's OK). Now, the browser can't find that URL. I also need to know how to set this up on a new server, so instead of wasting time diagnosing this problem (probably just something dumb I did messing with settings or something), I really need to know how to set this up from scratch. Thanks for taking the time to read this and (hopefully) answer!

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  • How can I make a Prism webapp look like Firefox to a website? (user agent spoofing)

    - by Alex Aaron Goven
    I thought it would be cool to use Mozilla's Prism to create a webapp for min.us, but drag and drop is disallowed because the site doesn't see the program as Firefox, Chrome or Safari, those of which are apparently the only browsers allowed to do drag and drop for fear that something will be horribly broken. I'm pretty sure Prism runs on the same engine as Firefox, yet I wouldn't doubt it if Prism is running on an older version since it's kind of a forgotten beta. Anyways, like the title says, I want to be able to make Prism webapps appear look like Firefox to websites to unlock awesome features. Also, if it can only be done with Fluid, then I answers regarding that will be fine. I'm not sure what engine it's running though.

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  • How to find a user's (or mine) access rights on Windows Server 2008?

    - by Faiz
    I was given access to a Windows Server 2008 box and I need to check what all permissions I have on that box (if possible in the entire domain). I don't have access to domain controller and I don't want to write LDAP queries but just some GUI option or some command line stuff. Is there anyway? PS: I am not in to network administration, I am a BI developer. Pardon me if asked a stupid question.

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  • Q1 2010 New Feature: Paging with RadGridView for Silverlight and WPF

    We are glad to announce that the Q1 2010 Release has added another weapon to RadGridViews growing arsenal of features. This is the brand new RadDataPager control which provides the user interface for paging through a collection of data. The good news is that RadDataPager can be used to page any collection. It does not depend on RadGridView in any way, so you will be free to use it with the rest of your ItemsControls if you chose to do so. Before you read on, you might want to download the samples solution that I have attached. It contains a sample project for every scenario that I will discuss later on. Looking at the code while reading will make things much easier for you. There is something for everyone among the 10 Visual Studio projects that are included in the solution. So go and grab it. I. Paging essentials The single most important piece of software concerning paging in Silverlight is the System.ComponentModel.IPagedCollectionView interface. Those of you who are on the WPF front need not worry though. As you might already know, Teleriks Silverlight and WPF controls is share the same code-base. Since WPF does not contain a similar interface, Telerik has provided its own Telerik.Windows.Data.IPagedCollectionView. The IPagedCollectionView interface contains several important members which are used by RadGridView to perform the actual paging. Silverlight provides a default implementation of this interface which, naturally, is called PagedCollectionView. You should definitely take a look at its source code in case you are interested in what is going on under the hood. But this is not a prerequisite for our discussion. The WPF default implementation of the interface is Teleriks QueryableCollectionView which, among many other interfaces, implements IPagedCollectionView. II. No Paging In order to gradually build up my case, I will start with a very simple example that lacks paging whatsoever. It might sound stupid, but this will help us build on top of this paging-devoid example. Let us imagine that we have the simplest possible scenario. That is a simple IEnumerable and an ItemsControl that shows its contents. This will look like this: No Paging IEnumerable itemsSource = Enumerable.Range(0, 1000); this.itemsControl.ItemsSource = itemsSource; XAML <Border Grid.Row="0" BorderBrush="Black" BorderThickness="1" Margin="5">     <ListBox Name="itemsControl"/> </Border> <Border Grid.Row="1" BorderBrush="Black" BorderThickness="1" Margin="5">     <TextBlock Text="No Paging"/> </Border> Nothing special for now. Just some data displayed in a ListBox. The two sample projects in the solution that I have attached are: NoPaging_WPF NoPaging_SL3 With every next sample those two project will evolve in some way or another. III. Paging simple collections The single most important property of RadDataPager is its Source property. This is where you pass in your collection of data for paging. More often than not your collection will not be an IPagedCollectionView. It will either be a simple List<T>, or an ObservableCollection<T>, or anything that is simply IEnumerable. Unless you had paging in mind when you designed your project, it is almost certain that your data source will not be pageable out of the box. So what are the options? III. 1. Wrapping the simple collection in an IPagedCollectionView If you look at the constructors of PagedCollectionView and QueryableCollectionView you will notice that you can pass in a simple IEnumerable as a parameter. Those two classes will wrap it and provide paging capabilities over your original data. In fact, this is what RadGridView does internally. It wraps your original collection in an QueryableCollectionView in order to easily perform many useful tasks such as filtering, sorting, and others, but in our case the most important one is paging. So let us start our series of examples with the most simplistic one. Imagine that you have a simple IEnumerable which is the source for an ItemsControl. Here is how to wrap it in order to enable paging: Silverlight IEnumerable itemsSource = Enumerable.Range(0, 1000); var pagedSource = new PagedCollectionView(itemsSource); this.radDataPager.Source = pagedSource; this.itemsControl.ItemsSource = pagedSource; WPF IEnumerable itemsSource = Enumerable.Range(0, 1000); var pagedSource = new QueryableCollectionView(itemsSource); this.radDataPager.Source = pagedSource; this.itemsControl.ItemsSource = pagedSource; XAML <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <ListBox Name="itemsControl"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> This will do the trick. It is quite simple, isnt it? The two sample projects in the solution that I have attached are: PagingSimpleCollectionWithWrapping_WPF PagingSimpleCollectionWithWrapping_SL3 III. 2. Binding to RadDataPager.PagedSource In case you do not like this approach there is a better one. When you assign an IEnumerable as the Source of a RadDataPager it will automatically wrap it in a QueryableCollectionView and expose it through its PagedSource property. From then on, you can attach any number of ItemsControls to the PagedSource and they will be automatically paged. Here is how to do this entirely in XAML: Using RadDataPager.PagedSource <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1" Margin="5">     <ListBox Name="itemsControl"              ItemsSource="{Binding PagedSource, ElementName=radDataPager}"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               Source="{Binding ItemsSource}"                              PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> The two sample projects in the solution that I have attached are: PagingSimpleCollectionWithPagedSource_WPF PagingSimpleCollectionWithPagedSource_SL3 IV. Paging collections implementing IPagedCollectionView Those of you who are using WCF RIA Services should feel very lucky. After a quick look with Reflector or the debugger we can see that the DomainDataSource.Data property is in fact an instance of the DomainDataSourceView class. This class implements a handful of useful interfaces: ICollectionView IEnumerable INotifyCollectionChanged IEditableCollectionView IPagedCollectionView INotifyPropertyChanged Luckily, IPagedCollectionView is among them which lets you do the whole paging in the server. So lets do this. We will add a DomainDataSource control to our page/window and connect the items control and the pager to it. Here is how to do this: MainPage <riaControls:DomainDataSource x:Name="invoicesDataSource"                               AutoLoad="True"                               QueryName="GetInvoicesQuery">     <riaControls:DomainDataSource.DomainContext>         <services:ChinookDomainContext/>     </riaControls:DomainDataSource.DomainContext> </riaControls:DomainDataSource> <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <ListBox Name="itemsControl"              ItemsSource="{Binding Data, ElementName=invoicesDataSource}"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               Source="{Binding Data, ElementName=invoicesDataSource}"                              PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> By the way, you can replace the ListBox from the above code snippet with any other ItemsControl. It can be RadGridView, it can be the MS DataGrid, you name it. Essentially, RadDataPager is sending paging commands to the the DomainDataSource.Data. It does not care who, what, or how many different controls are bound to this same Data property of the DomainDataSource control. So if you would like to experiment with this, you can throw in any number of other ItemsControls next to the ListBox, bind them in the same manner, and all of them will be paged by our single RadDataPager. Furthermore, you can throw in any number of RadDataPagers and bind them to the same property. Then when you page with any one of them will automatically update all of the rest. The whole picture is simply beautiful and we can do all of this thanks to WCF RIA Services. The two sample projects (Silverlight only) in the solution that I have attached are: PagingIPagedCollectionView PagingIPagedCollectionView.Web IV. Paging RadGridView While you can replace the ListBox in any of the above examples with a RadGridView, RadGridView offers something extra. Similar to the DomainDataSource.Data property, the RadGridView.Items collection implements the IPagedCollectionView interface. So you are already thinking: Then why not bind the Source property of RadDataPager to RadGridView.Items? Well thats exactly what you can do and you will start paging RadGridView out-of-the-box. It is as simple as that, no code-behind is involved: MainPage <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1" Margin="5">     <telerikGrid:RadGridView Name="radGridView"                              ItemsSource="{Binding ItemsSource}"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               Source="{Binding Items, ElementName=radGridView}"                              PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> The two sample projects in the solution that I have attached are: PagingRadGridView_SL3 PagingRadGridView_WPF With this last example I think I have covered every possible paging combination. In case you would like to see an example of something that I have not covered, please let me know. Also, make sure you check out those great online examples: WCF RIA Services with DomainDataSource Paging Configurator Endless Paging Paging Any Collection Paging RadGridView Happy Paging! Download Full Source Code Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • How to make creating viewmodels at runtime less painful

    - by Mr Happy
    I apologize for the long question, it reads a bit as a rant, but I promise it's not! I've summarized my question(s) below In the MVC world, things are straightforward. The Model has state, the View shows the Model, and the Controller does stuff to/with the Model (basically), a controller has no state. To do stuff the Controller has some dependencies on web services, repository, the lot. When you instantiate a controller you care about supplying those dependencies, nothing else. When you execute an action (method on Controller), you use those dependencies to retrieve or update the Model or calling some other domain service. If there's any context, say like some user wants to see the details of a particular item, you pass the Id of that item as parameter to the Action. Nowhere in the Controller is there any reference to any state. So far so good. Enter MVVM. I love WPF, I love data binding. I love frameworks that make data binding to ViewModels even easier (using Caliburn Micro a.t.m.). I feel things are less straightforward in this world though. Let's do the exercise again: the Model has state, the View shows the ViewModel, and the ViewModel does stuff to/with the Model (basically), a ViewModel does have state! (to clarify; maybe it delegates all the properties to one or more Models, but that means it must have a reference to the model one way or another, which is state in itself) To do stuff the ViewModel has some dependencies on web services, repository, the lot. When you instantiate a ViewModel you care about supplying those dependencies, but also the state. And this, ladies and gentlemen, annoys me to no end. Whenever you need to instantiate a ProductDetailsViewModel from the ProductSearchViewModel (from which you called the ProductSearchWebService which in turn returned IEnumerable<ProductDTO>, everybody still with me?), you can do one of these things: call new ProductDetailsViewModel(productDTO, _shoppingCartWebService /* dependcy */);, this is bad, imagine 3 more dependencies, this means the ProductSearchViewModel needs to take on those dependencies as well. Also changing the constructor is painful. call _myInjectedProductDetailsViewModelFactory.Create().Initialize(productDTO);, the factory is just a Func, they are easily generated by most IoC frameworks. I think this is bad because Init methods are a leaky abstraction. You also can't use the readonly keyword for fields that are set in the Init method. I'm sure there are a few more reasons. call _myInjectedProductDetailsViewModelAbstractFactory.Create(productDTO); So... this is the pattern (abstract factory) that is usually recommended for this type of problem. I though it was genius since it satisfies my craving for static typing, until I actually started using it. The amount of boilerplate code is I think too much (you know, apart from the ridiculous variable names I get use). For each ViewModel that needs runtime parameters you'll get two extra files (factory interface and implementation), and you need to type the non-runtime dependencies like 4 extra times. And each time the dependencies change, you get to change it in the factory as well. It feels like I don't even use a DI container anymore. (I think Castle Windsor has some kind of solution for this [with it's own drawbacks, correct me if I'm wrong]). do something with anonymous types or dictionary. I like my static typing. So, yeah. Mixing state and behavior in this way creates a problem which don't exist at all in MVC. And I feel like there currently isn't a really adequate solution for this problem. Now I'd like to observe some things: People actually use MVVM. So they either don't care about all of the above, or they have some brilliant other solution. I haven't found an in-depth example of MVVM with WPF. For example, the NDDD-sample project immensely helped me understand some DDD concepts. I'd really like it if someone could point me in the direction of something similar for MVVM/WPF. Maybe I'm doing MVVM all wrong and I should turn my design upside down. Maybe I shouldn't have this problem at all. Well I know other people have asked the same question so I think I'm not the only one. To summarize Am I correct to conclude that having the ViewModel being an integration point for both state and behavior is the reason for some difficulties with the MVVM pattern as a whole? Is using the abstract factory pattern the only/best way to instantiate a ViewModel in a statically typed way? Is there something like an in depth reference implementation available? Is having a lot of ViewModels with both state/behavior a design smell?

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