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  • Change a select list display value upon selecting description

    - by eli
    Hello, I would like a select list that does the following: When the select list is open, display the list of descriptions. When the user selects an item, the select list will close an only the value will be displayed. The reason for this is to conserve space as the values will be much shorter. I'm hoping that there's an answer in jQuery. Thanks.

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  • Get a list of all installed applications on Blackberry

    - by Fermin
    Hi, Is it possible to get a list of all applications installed in a Blackberry, similar to the applications list when you go into your settings. I can get a list of all visible applications using the following but I was wondering if it's possible to get a list of apps that aren't necessarily running but are installed, ApplicationDescriptor[] descriptors = ApplicationManager.getApplicationManager().getVisibleApplications();

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  • Javascript: Enable checkboxes list when a checkbox is checked (With Prototype)

    - by BoDiE2003
    Guys, Ive been using jquery to do this, but now I need to do it with Prototype and Im little confused due lack of documentation I have 2 lists of check boxes First List: Check box 1 Check box 2 Second list: Check box x check box y check box z I need the JS code, using prototype to work like this: Second list, remains disabled unless I check one of the checkboxes of the First List. Any suggestions, or help, please! Thankyou.

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  • Binary search in rotated sorted list

    - by Algorist
    I am having a sorted list which is rotated and I would like to do a binary search on that list to find the minimum element. Lets suppose initial list is {1,2,3,4,5,6,7,8} rotated list can be like {5,6,7,8,1,2,3,4} Normal binary search doesn't work in this case. Any idea how to do this.

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  • Filter list as a parameter in a compiled query

    - by JK
    I have the following compiled query that I want to return a list of "groups" that don't have a "GroupID" that's contained in a filtered list: CompiledQuery.Compile(ConfigEntities contexty, List list) = from c in context.Groups where (!csList.Contains(c.GroupID)) select c).ToList() However I'm getting the following run-time error: The specified parameter 'categories' of type 'System.Collections.Generic.List`1[[System.Int32, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c261364e126]]' is not valid. Only scalar parameters (such as Int32, Decimal, and Guid) are supported. Any ideas?

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  • Why is my List.Sort method in C# reversing the order of my list?

    - by Fiona Holder
    I have a list of items in a generic list: A1 (sort index 1) A2 (sort index 2) B1 (sort index 3) B2 (sort index 3) B3 (sort index 3) The comparator on them takes the form: this.sortIndex.CompareTo(other.sortIndex) When I do a List.Sort() on the list of items, I get the following order out: A1 A2 B3 B2 B1 It has obviously worked in the sense that the sort indexes are in the right order, but I really don't want it to be re-ordering the 'B' items. Is there any tweak I can make to my comparator to fix this?

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  • use JQuery to get a list of classes

    - by John
    Hi I have a un-ordered (ul) html list. Each li item has 1 or more classes attached to it. I want to go through this ul list and get all the (distinct) classes. Then from this list create a list of checkboxes who's value matches that of the class and also who's label matches that of the class. One checkbox for each class. What is the best way to do this using JQuery? Thanks

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  • convert class object collection to List

    - by prince23
    hi, here i have an return type as class object collection. where Emp is class , having properties like Fname, lname,Age WebApplication1.kumar .Job Emp = objEmp.GetJobInfo2(1); i need to convert the oject collections into List List objEmp = new List(); what is the steps that i need to do here to convert class object to List thanks in advance

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  • Getting the position of the element in a list when it's drag/dropped (ui.sortable)

    - by Wurlitzer
    Hi, I have a sortable list like this one: http://jqueryui.com/demos/sortable Is it possible to get the start and end position of the element in the list, when it has been moved? I'm talking about their position number, in the list. For example, if I move element 2 to position 5 in the list, I'd like to assign those two numbers to variables. I'm new to jQuery - any help would be much appreciated.

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  • In python, what does len(list) do?

    - by nsharish
    My doubt is that if the len(list) calculates the length of the list everytime it is called or it returns the value of the builtin counter.I have a context where i need to check the length of list everytime in a loop, likelistData = [] for value in ioread(): if len(listData)=25: processlistdata() clearlistdata() listData.append(value) Should I check len(listData) every iteration, or can I have a counter for the length of the list.

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  • C# Linq - Cannot implicitly convert IEnumerable<string> to List<string>

    - by JL
    I have a List defined like this : public List<string> AttachmentURLS; I am adding items to the list like this: instruction.AttachmentURLS = curItem.Attributes["ows_Attachments"].Value.Split(';').ToList().Where(Attachment => !String.IsNullOrEmpty(Attachment)); But I am getting this error: Cannot implicitly convert IEnumerable to List What am I doing wrong?

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  • How to get "Friends who like/play games" list (similar to Farmville 2)

    - by FBAppDev
    I'm working on a Facebook app, and I'm trying to get a friends list similar to Farmville 2. They have a "friends who like games" list. My first thought is, I can get a list of all friends, then for each friend, see if they like any pages with type == "GAMES/TOYS". But ideally, I would like to get the list in one query (not by making one graph API or FQL request per friend). Is this possible, and if so, how?

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  • unable to pas derived List<>

    - by Tarscher
    Hi all, I have class A {} class B : A {} I also have a method that expects a List parameter void AMethod(List<A> parameter) {} Why can't I List<B> bs = new List<B>(); AMethod(bs); And secondly what is the most elegant way to make this work? regards

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  • How do I print this list vertically?

    - by UnworthyToast
    Let's say I have this list of asterisks, and I say it to print this way: list = ['* *', '*', '* * *', '* * * * *', '* * * * * *', '* * * *'] for i in list: print i So here, the output is: * * * * * * * * * * * * * * * * * * * * * But I want the output to be vertical, like this: * * * * * * * * * * * * * * * * * * * * * Any tips on doing this? I've tried to conceptualize how to use things like list comprehension or for-loops for this, but haven't got it quite right.

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  • jquery select list remove

    - by mazhar
    there are 2 multiple select list on my page , one is there with a seperate remove button . selecting an item there in the selected list is removing the item from the first select list also.how will i specify which list to remove item from in this code $().ready(function() { $('#remove').click(function() { return !$('#FeatureList option:selected').remove(); }); });

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  • Check exact match of a word in a list of words

    - by Flake
    I want to check if a word is in a list of words. word = "with" word_list = ["without", "bla", "foo", "bar"] I tried if word in set(list), but it is not yielding the wanted result due to the fact in is matching string rather than item. That is to say, "with" is a match in any of the words in the word_list but still if "with" in set(list) will say True. What is a simpler way for doing this check than manually iterate over the list?

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  • Look up or insert new element to string list in Haskell

    - by nightscream
    So I want to have a function that takes a String and a list as an argument, and checks if that element is already on the list, if it is, returns the same list, if it isnt, adds it to the list and returns it, 'im a begginer with haskell so heres what I have tried with no sucess: check:: String ->[String] ->[String] check x [] = []++[x] check x (y:xs) | x==y = (y:xs) | otherwise = check x xs Can someone point me the way ? thks

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  • Module configuration and layout configuration in zend framework.

    - by Prasanth P
    Hi all, I got some codes from other articles for configuring module and layout in zend framework. I tried with in my local. i didn't get different layout for default and admin module. Here is my code for configuring module and layout for zend framework. configs/application.ini [production] # Debug output phpSettings.display_startup_errors = 0 phpSettings.display_errors = 0 # Include path includePaths.library = APPLICATION_PATH "/../library" # Bootstrap bootstrap.path = APPLICATION_PATH "/Bootstrap.php" bootstrap.class = "Bootstrap" admin.bootstrap.path = APPLICATION_PATH "/modules/admin/Bootstrap.php" admin.bootstrap.class = "admin_Bootstrap" # Front Controller resources.frontController.controllerDirectory = APPLICATION_PATH "/controllers" resources.frontController.env = APPLICATION_ENV # Session resources.session.name = "ZendSession" resources.session.save_path = APPLICATION_PATH "/../data/session" resources.session.remember_me_seconds = 86400 # Layout resources.layout.layout = "layout" resources.layout.layoutPath = APPLICATION_PATH "/layouts" admin.resources.layout.layout = "admin" admin.resources.layout.layoutPath = APPLICATION_PATH "/modules/admin/layouts" # Views resources.view.encoding = "UTF-8" resources.view.basePath = APPLICATION_PATH "/views/" resources.view[] = resources.frontController.moduleDirectory = APPLICATION_PATH "/modules" resources.modules[] = resources.view[] = admin.resources.view[] = [staging : production] [testing : production] phpSettings.display_startup_errors = 1 phpSettings.display_errors = 1 [development : production] phpSettings.display_startup_errors = 1 phpSettings.display_errors = 1 application/Bootstrap.php <?php /** * Ensure all communications are managed by sessions. */ require_once ('Zend/Session.php'); Zend_Session::start(); class Bootstrap extends Zend_Application_Bootstrap_Bootstrap { protected function _initDoctype() { $this->bootstrap( 'view' ); $view = $this->getResource( 'view' ); $view->navigation = array(); $view->subnavigation = array(); $view->headTitle( 'Module One' ); $view->headLink()->appendStylesheet('/css/clear.css'); $view->headLink()->appendStylesheet('/css/main.css'); $view->headScript()->appendFile('/js/jquery.js'); $view->doctype( 'XHTML1_STRICT' ); //$view->navigation = $this->buildMenu(); } /*protected function _initAppAutoLoad() { $autoloader = new Zend_Application_Module_Autoloader(array( 'namespace' => 'default', 'basePath' => APPLICATION_PATH )); return $autoloader; }*/ protected function _initLayoutHelper() { $this->bootstrap('frontController'); $layout = Zend_Controller_Action_HelperBroker::addHelper( new ModuleLayoutLoader()); } public function _initControllers() { $front = Zend_Controller_Front::getInstance(); $front->addModuleDirectory(APPLICATION_PATH . '/modules/admin/', 'admin'); } protected function _initAutoLoadModuleAdmin() { $autoloader = new Zend_Application_module_Autoloader(array( 'namespace' => 'Admin', 'basePath' => APPLICATION_PATH . '/modules/admin' )); return $autoloader; } protected function _initModuleutoload() { $autoloader = new Zend_Application_Module_Autoloader ( array ('namespace' => '', 'basePath' => APPLICATION_PATH ) ); return $autoloader; } } class ModuleLayoutLoader extends Zend_Controller_Action_Helper_Abstract // looks up layout by module in application.ini { public function preDispatch() { $bootstrap = $this->getActionController() ->getInvokeArg('bootstrap'); $config = $bootstrap->getOptions(); echo $module = $this->getRequest()->getModuleName(); /*echo "Configs : <pre>"; print_r($config[$module]);*/ if (isset($config[$module]['resources']['layout']['layout'])) { $layoutScript = $config[$module]['resources']['layout']['layout']; $this->getActionController() ->getHelper('layout') ->setLayout($layoutScript); } } } application/modules/admin/Bootstrap.php <?php class Admin_Bootstrap extends Zend_Application_Module_Bootstrap { /*protected function _initAppAutoload() { $autoloader = new Zend_Application_Module_Autoloader(array( 'namespace' => 'admin', 'basePath' => APPLICATION_PATH . '/modules/admin/' )); return $autoloader; }*/ protected function _initDoctype() { $this->bootstrap( 'view' ); $view = $this->getResource( 'view' ); $view->navigation = array(); $view->subnavigation = array(); $view->headTitle( 'Module One' ); $view->headLink()->appendStylesheet('/css/clear.css'); $view->headLink()->appendStylesheet('/css/main.css'); $view->headScript()->appendFile('/js/jquery.js'); $view->doctype( 'XHTML1_STRICT' ); //$view->navigation = $this->buildMenu(); } } Please go through it and let me know any knows how do configure module and layout in right way.. Thanks and regards, Prasanth P

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  • Building applications with WPF, MVVM and Prism(aka CAG)

    - by skjagini
    In this article I am going to walk through an application using WPF and Prism (aka composite application guidance, CAG) which simulates engaging a taxi (cab).  The rules are simple, the app would have3 screens A login screen to authenticate the user An information screen. A screen to engage the cab and roam around and calculating the total fare Metered Rate of Fare The meter is required to be engaged when a cab is occupied by anyone $3.00 upon entry $0.35 for each additional unit The unit fare is: one-fifth of a mile, when the cab is traveling at 6 miles an hour or more; or 60 seconds when not in motion or traveling at less than 12 miles per hour. Night surcharge of $.50 after 8:00 PM & before 6:00 AM Peak hour Weekday Surcharge of $1.00 Monday - Friday after 4:00 PM & before 8:00 PM New York State Tax Surcharge of $.50 per ride. Example: Friday (2010-10-08) 5:30pm Start at Lexington Ave & E 57th St End at Irving Pl & E 15th St Start = $3.00 Travels 2 miles at less than 6 mph for 15 minutes = $3.50 Travels at more than 12 mph for 5 minutes = $1.75 Peak hour Weekday Surcharge = $1.00 (ride started at 5:30 pm) New York State Tax Surcharge = $0.50 Before we dive into the app, I would like to give brief description about the framework.  If you want to jump on to the source code, scroll all the way to the end of the post. MVVM MVVM pattern is in no way related to the usage of PRISM in your application and should be considered if you are using WPF irrespective of PRISM or not. Lets say you are not familiar with MVVM, your typical UI would involve adding some UI controls like text boxes, a button, double clicking on the button,  generating event handler, calling a method from business layer and updating the user interface, it works most of the time for developing small scale applications. The problem with this approach is that there is some amount of code specific to business logic wrapped in UI specific code which is hard to unit test it, mock it and MVVM helps to solve the exact problem. MVVM stands for Model(M) – View(V) – ViewModel(VM),  based on the interactions with in the three parties it should be called VVMM,  MVVM sounds more like MVC (Model-View-Controller) so the name. Why it should be called VVMM: ViewView Model - Model WPF allows to create user interfaces using XAML and MVVM takes it to the next level by allowing complete separation of user interface and business logic. In WPF each view will have a property, DataContext when set to an instance of a class (which happens to be your view model) provides the data the view is interested in, i.e., view interacts with view model and at the same time view model interacts with view through DataContext. Sujith, if view and view model are interacting directly with each other how does MVVM is helping me separation of concerns? Well, the catch is DataContext is of type Object, since it is of type object view doesn’t know exact type of view model allowing views and views models to be loosely coupled. View models aggregate data from models (data access layer, services, etc) and make it available for views through properties, methods etc, i.e., View Models interact with Models. PRISM Prism is provided by Microsoft Patterns and Practices team and it can be downloaded from codeplex for source code,  samples and documentation on msdn.  The name composite implies, to compose user interface from different modules (views) without direct dependencies on each other, again allowing  loosely coupled development. Well Sujith, I can already do that with user controls, why shall I learn another framework?  That’s correct, you can decouple using user controls, but you still have to manage some amount of coupling, like how to do you communicate between the controls, how do you subscribe/unsubscribe, loading/unloading views dynamically. Prism is not a replacement for user controls, provides the following features which greatly help in designing the composite applications. Dependency Injection (DI)/ Inversion of Control (IoC) Modules Regions Event Aggregator  Commands Simply put, MVVM helps building a single view and Prism helps building an application using the views There are other open source alternatives to Prism, like MVVMLight, Cinch, take a look at them as well. Lets dig into the source code.  1. Solution The solution is made of the following projects Framework: Holds the common functionality in building applications using WPF and Prism TaxiClient: Start up project, boot strapping and app styling TaxiCommon: Helps with the business logic TaxiModules: Holds the meat of the application with views and view models TaxiTests: To test the application 2. DI / IoC Dependency Injection (DI) as the name implies refers to injecting dependencies and Inversion of Control (IoC) means the calling code has no direct control on the dependencies, opposite of normal way of programming where dependencies are passed by caller, i.e inversion; aside from some differences in terminology the concept is same in both the cases. The idea behind DI/IoC pattern is to reduce the amount of direct coupling between different components of the application, the higher the dependency the more tightly coupled the application resulting in code which is hard to modify, unit test and mock.  Initializing Dependency Injection through BootStrapper TaxiClient is the starting project of the solution and App (App.xaml)  is the starting class that gets called when you run the application. From the App’s OnStartup method we will invoke BootStrapper.   namespace TaxiClient { /// <summary> /// Interaction logic for App.xaml /// </summary> public partial class App : Application { protected override void OnStartup(StartupEventArgs e) { base.OnStartup(e);   (new BootStrapper()).Run(); } } } BootStrapper is your contact point for initializing the application including dependency injection, creating Shell and other frameworks. We are going to use Unity for DI and there are lot of open source DI frameworks like Spring.Net, StructureMap etc with different feature set  and you can choose a framework based on your preferences. Note that Prism comes with in built support for Unity, for example we are deriving from UnityBootStrapper in our case and for any other DI framework you have to extend the Prism appropriately   namespace TaxiClient { public class BootStrapper: UnityBootstrapper { protected override IModuleCatalog CreateModuleCatalog() { return new ConfigurationModuleCatalog(); } protected override DependencyObject CreateShell() { Framework.FrameworkBootStrapper.Run(Container, Application.Current.Dispatcher);   Shell shell = new Shell(); shell.ResizeMode = ResizeMode.NoResize; shell.Show();   return shell; } } } Lets take a look into  FrameworkBootStrapper to check out how to register with unity container. namespace Framework { public class FrameworkBootStrapper { public static void Run(IUnityContainer container, Dispatcher dispatcher) { UIDispatcher uiDispatcher = new UIDispatcher(dispatcher); container.RegisterInstance<IDispatcherService>(uiDispatcher);   container.RegisterType<IInjectSingleViewService, InjectSingleViewService>( new ContainerControlledLifetimeManager());   . . . } } } In the above code we are registering two components with unity container. You shall observe that we are following two different approaches, RegisterInstance and RegisterType.  With RegisterInstance we are registering an existing instance and the same instance will be returned for every request made for IDispatcherService   and with RegisterType we are requesting unity container to create an instance for us when required, i.e., when I request for an instance for IInjectSingleViewService, unity will create/return an instance of InjectSingleViewService class and with RegisterType we can configure the life time of the instance being created. With ContaienrControllerLifetimeManager, the unity container caches the instance and reuses for any subsequent requests, without recreating a new instance. Lets take a look into FareViewModel.cs and it’s constructor. The constructor takes one parameter IEventAggregator and if you try to find all references in your solution for IEventAggregator, you will not find a single location where an instance of EventAggregator is passed directly to the constructor. The compiler still finds an instance and works fine because Prism is already configured when used with Unity container to return an instance of EventAggregator when requested for IEventAggregator and in this particular case it is called constructor injection. public class FareViewModel:ObservableBase, IDataErrorInfo { ... private IEventAggregator _eventAggregator;   public FareViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator; InitializePropertyNames(); InitializeModel(); PropertyChanged += OnPropertyChanged; } ... 3. Shell Shells are very similar in operation to Master Pages in asp.net or MDI in Windows Forms. And shells contain regions which display the views, you can have as many regions as you wish in a given view. You can also nest regions. i.e, one region can load a view which in itself may contain other regions. We have to create a shell at the start of the application and are doing it by overriding CreateShell method from BootStrapper From the following Shell.xaml you shall notice that we have two content controls with Region names as ‘MenuRegion’ and ‘MainRegion’.  The idea here is that you can inject any user controls into the regions dynamically, i.e., a Menu User Control for MenuRegion and based on the user action you can load appropriate view into MainRegion.    <Window x:Class="TaxiClient.Shell" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Regions="clr-namespace:Microsoft.Practices.Prism.Regions;assembly=Microsoft.Practices.Prism" Title="Taxi" Height="370" Width="800"> <Grid Margin="2"> <ContentControl Regions:RegionManager.RegionName="MenuRegion" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" />   <ContentControl Grid.Row="1" Regions:RegionManager.RegionName="MainRegion" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" /> <!--<Border Grid.ColumnSpan="2" BorderThickness="2" CornerRadius="3" BorderBrush="LightBlue" />-->   </Grid> </Window> 4. Modules Prism provides the ability to build composite applications and modules play an important role in it. For example if you are building a Mortgage Loan Processor application with 3 components, i.e. customer’s credit history,  existing mortgages, new home/loan information; and consider that the customer’s credit history component involves gathering data about his/her address, background information, job details etc. The idea here using Prism modules is to separate the implementation of these 3 components into their own visual studio projects allowing to build components with no dependency on each other and independently. If we need to add another component to the application, the component can be developed by in house team or some other team in the organization by starting with a new Visual Studio project and adding to the solution at the run time with very little knowledge about the application. Prism modules are defined by implementing the IModule interface and each visual studio project to be considered as a module should implement the IModule interface.  From the BootStrapper.cs you shall observe that we are overriding the method by returning a ConfiguratingModuleCatalog which returns the modules that are registered for the application using the app.config file  and you can also add module using code. Lets take a look into configuration file.   <?xml version="1.0"?> <configuration> <configSections> <section name="modules" type="Microsoft.Practices.Prism.Modularity.ModulesConfigurationSection, Microsoft.Practices.Prism"/> </configSections> <modules> <module assemblyFile="TaxiModules.dll" moduleType="TaxiModules.ModuleInitializer, TaxiModules" moduleName="TaxiModules"/> </modules> </configuration> Here we are adding TaxiModules project to our solution and TaxiModules.ModuleInitializer implements IModule interface   5. Module Mapper With Prism modules you can dynamically add or remove modules from the regions, apart from that Prism also provides API to control adding/removing the views from a region within the same module. Taxi Information Screen: Engage the Taxi Screen: The sample application has two screens, ‘Taxi Information’ and ‘Engage the Taxi’ and they both reside in same module, TaxiModules. ‘Engage the Taxi’ is again made of two user controls, FareView on the left and TotalView on the right. We have created a Shell with two regions, MenuRegion and MainRegion with menu loaded into MenuRegion. We can create a wrapper user control called EngageTheTaxi made of FareView and TotalView and load either TaxiInfo or EngageTheTaxi into MainRegion based on the user action. Though it will work it tightly binds the user controls and for every combination of user controls, we need to create a dummy wrapper control to contain them. Instead we can apply the principles we learned so far from Shell/regions and introduce another template (LeftAndRightRegionView.xaml) made of two regions Region1 (left) and Region2 (right) and load  FareView and TotalView dynamically.  To help with loading of the views dynamically I have introduce an helper an interface, IInjectSingleViewService,  idea suggested by Mike Taulty, a must read blog for .Net developers. using System; using System.Collections.Generic; using System.ComponentModel;   namespace Framework.PresentationUtility.Navigation {   public interface IInjectSingleViewService : INotifyPropertyChanged { IEnumerable<CommandViewDefinition> Commands { get; } IEnumerable<ModuleViewDefinition> Modules { get; }   void RegisterViewForRegion(string commandName, string viewName, string regionName, Type viewType); void ClearViewFromRegion(string viewName, string regionName); void RegisterModule(string moduleName, IList<ModuleMapper> moduleMappers); } } The Interface declares three methods to work with views: RegisterViewForRegion: Registers a view with a particular region. You can register multiple views and their regions under one command.  When this particular command is invoked all the views registered under it will be loaded into their regions. ClearViewFromRegion: To unload a specific view from a region. RegisterModule: The idea is when a command is invoked you can load the UI with set of controls in their default position and based on the user interaction, you can load different contols in to different regions on the fly.  And it is supported ModuleViewDefinition and ModuleMappers as shown below. namespace Framework.PresentationUtility.Navigation { public class ModuleViewDefinition { public string ModuleName { get; set; } public IList<ModuleMapper> ModuleMappers; public ICommand Command { get; set; } }   public class ModuleMapper { public string ViewName { get; set; } public string RegionName { get; set; } public Type ViewType { get; set; } } } 6. Event Aggregator Prism event aggregator enables messaging between components as in Observable pattern, Notifier notifies the Observer which receives notification it is interested in. When it comes to Observable pattern, Observer has to unsubscribes for notifications when it no longer interested in notifications, which allows the Notifier to remove the Observer’s reference from it’s local cache. Though .Net has managed garbage collection it cannot remove inactive the instances referenced by an active instance resulting in memory leak, keeping the Observers in memory as long as Notifier stays in memory.  Developers have to be very careful to unsubscribe when necessary and it often gets overlooked, to overcome these problems Prism Event Aggregator uses weak references to cache the reference (Observer in this case)  and releases the reference (memory) once the instance goes out of scope. Using event aggregator is very simple, declare a generic type of CompositePresenationEvent by inheriting from it. using Microsoft.Practices.Prism.Events; using TaxiCommon.BAO;   namespace TaxiCommon.CompositeEvents { public class TaxiOnMoveEvent:CompositePresentationEvent<TaxiOnMove> { } }   TaxiOnMove.cs includes the properties which we want to exchange between the parties, FareView and TotalView. using System;   namespace TaxiCommon.BAO { public class TaxiOnMove { public TimeSpan MinutesAtTweleveMPH { get; set; } public double MilesAtSixMPH { get; set; } } }   Lets take a look into FareViewodel (Notifier) and how it raises the event.  Here we are raising the event by getting the event through GetEvent<..>() and publishing it with the payload private void OnAddMinutes(object obj) { TaxiOnMove payload = new TaxiOnMove(); if(MilesAtSixMPH != null) payload.MilesAtSixMPH = MilesAtSixMPH.Value; if(MinutesAtTweleveMPH != null) payload.MinutesAtTweleveMPH = new TimeSpan(0,0,MinutesAtTweleveMPH.Value,0);   _eventAggregator.GetEvent<TaxiOnMoveEvent>().Publish(payload); ResetMinutesAndMiles(); } And TotalViewModel(Observer) subscribes to notifications by getting the event through GetEvent<..>() namespace TaxiModules.ViewModels { public class TotalViewModel:ObservableBase { .... private IEventAggregator _eventAggregator;   public TotalViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator; ... }   private void SubscribeToEvents() { _eventAggregator.GetEvent<TaxiStartedEvent>() .Subscribe(OnTaxiStarted, ThreadOption.UIThread,false,(filter) => true); _eventAggregator.GetEvent<TaxiOnMoveEvent>() .Subscribe(OnTaxiMove, ThreadOption.UIThread, false, (filter) => true); _eventAggregator.GetEvent<TaxiResetEvent>() .Subscribe(OnTaxiReset, ThreadOption.UIThread, false, (filter) => true); }   ... private void OnTaxiMove(TaxiOnMove taxiOnMove) { OnMoveFare fare = new OnMoveFare(taxiOnMove); Fares.Add(fare); SetTotalFare(new []{fare}); }   .... 7. MVVM through example In this section we are going to look into MVVM implementation through example.  I have all the modules declared in a single project, TaxiModules, again it is not necessary to have them into one project. Once the user logs into the application, will be greeted with the ‘Engage the Taxi’ screen which is made of two user controls, FareView.xaml and TotalView.Xaml. As you can see from the solution explorer, each of them have their own code behind files and  ViewModel classes, FareViewMode.cs, TotalViewModel.cs Lets take a look in to the FareView and how it interacts with FareViewModel using MVVM implementation. FareView.xaml acts as a view and FareViewMode.cs is it’s view model. The FareView code behind class   namespace TaxiModules.Views { /// <summary> /// Interaction logic for FareView.xaml /// </summary> public partial class FareView : UserControl { public FareView(FareViewModel viewModel) { InitializeComponent(); this.Loaded += (s, e) => { this.DataContext = viewModel; }; } } } The FareView is bound to FareViewModel through the data context  and you shall observe that DataContext is of type Object, i.e. the FareView doesn’t really know the type of ViewModel (FareViewModel). This helps separation of View and ViewModel as View and ViewModel are independent of each other, you can bind FareView to FareViewModel2 as well and the application compiles just fine. Lets take a look into FareView xaml file  <UserControl x:Class="TaxiModules.Views.FareView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Toolkit="clr-namespace:Microsoft.Windows.Controls;assembly=WPFToolkit" xmlns:Commands="clr-namespace:Microsoft.Practices.Prism.Commands;assembly=Microsoft.Practices.Prism"> <Grid Margin="10" > ....   <Border Style="{DynamicResource innerBorder}" Grid.Row="0" Grid.Column="0" Grid.RowSpan="11" Grid.ColumnSpan="2" Panel.ZIndex="1"/>   <Label Grid.Row="0" Content="Engage the Taxi" Style="{DynamicResource innerHeader}"/> <Label Grid.Row="1" Content="Select the State"/> <ComboBox Grid.Row="1" Grid.Column="1" ItemsSource="{Binding States}" Height="auto"> <ComboBox.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding Name}"/> </DataTemplate> </ComboBox.ItemTemplate> <ComboBox.SelectedItem> <Binding Path="SelectedState" Mode="TwoWay"/> </ComboBox.SelectedItem> </ComboBox> <Label Grid.Row="2" Content="Select the Date of Entry"/> <Toolkit:DatePicker Grid.Row="2" Grid.Column="1" SelectedDate="{Binding DateOfEntry, ValidatesOnDataErrors=true}" /> <Label Grid.Row="3" Content="Enter time 24hr format"/> <TextBox Grid.Row="3" Grid.Column="1" Text="{Binding TimeOfEntry, TargetNullValue=''}"/> <Button Grid.Row="4" Grid.Column="1" Content="Start the Meter" Commands:Click.Command="{Binding StartMeterCommand}" />   <Label Grid.Row="5" Content="Run the Taxi" Style="{DynamicResource innerHeader}"/> <Label Grid.Row="6" Content="Number of Miles &lt;@6mph"/> <TextBox Grid.Row="6" Grid.Column="1" Text="{Binding MilesAtSixMPH, TargetNullValue='', ValidatesOnDataErrors=true}"/> <Label Grid.Row="7" Content="Number of Minutes @12mph"/> <TextBox Grid.Row="7" Grid.Column="1" Text="{Binding MinutesAtTweleveMPH, TargetNullValue=''}"/> <Button Grid.Row="8" Grid.Column="1" Content="Add Minutes and Miles " Commands:Click.Command="{Binding AddMinutesCommand}"/> <Label Grid.Row="9" Content="Other Operations" Style="{DynamicResource innerHeader}"/> <Button Grid.Row="10" Grid.Column="1" Content="Reset the Meter" Commands:Click.Command="{Binding ResetCommand}"/>   </Grid> </UserControl> The highlighted code from the above code shows data binding, for example ComboBox which displays list of states has it’s ItemsSource bound to States property, with DataTemplate bound to Name and SelectedItem  to SelectedState. You might be wondering what are all these properties and how it is able to bind to them.  The answer lies in data context, i.e., when you bound a control, WPF looks for data context on the root object (Grid in this case) and if it can’t find data context it will look into root’s root, i.e. FareView UserControl and it is bound to FareViewModel.  Each of those properties have be declared on the ViewModel for the View to bind correctly. To put simply, View is bound to ViewModel through data context of type object and every control that is bound on the View actually binds to the public property on the ViewModel. Lets look into the ViewModel code (the following code is not an exact copy of FareViewMode.cs, pasted relevant code for this section)   namespace TaxiModules.ViewModels { public class FareViewModel:ObservableBase, IDataErrorInfo { public List<USState> States { get { return USStates.StateList; } }   public USState SelectedState { get { return _selectedState; } set { _selectedState = value; RaisePropertyChanged(_selectedStatePropertyName); } }   public DateTime? DateOfEntry { get { return _dateOfEntry; } set { _dateOfEntry = value; RaisePropertyChanged(_dateOfEntryPropertyName); } }   public TimeSpan? TimeOfEntry { get { return _timeOfEntry; } set { _timeOfEntry = value; RaisePropertyChanged(_timeOfEntryPropertyName); } }   public double? MilesAtSixMPH { get { return _milesAtSixMPH; } set { _milesAtSixMPH = value; RaisePropertyChanged(_distanceAtSixMPHPropertyName); } }   public int? MinutesAtTweleveMPH { get { return _minutesAtTweleveMPH; } set { _minutesAtTweleveMPH = value; RaisePropertyChanged(_minutesAtTweleveMPHPropertyName); } }   public ICommand StartMeterCommand { get { if(_startMeterCommand == null) { _startMeterCommand = new DelegateCommand<object>(OnStartMeter, CanStartMeter); } return _startMeterCommand; } }   public ICommand AddMinutesCommand { get { if(_addMinutesCommand == null) { _addMinutesCommand = new DelegateCommand<object>(OnAddMinutes, CanAddMinutes); } return _addMinutesCommand; } }   public ICommand ResetCommand { get { if(_resetCommand == null) { _resetCommand = new DelegateCommand<object>(OnResetCommand); } return _resetCommand; } }   } private void OnStartMeter(object obj) { _eventAggregator.GetEvent<TaxiStartedEvent>().Publish( new TaxiStarted() { EngagedOn = DateOfEntry.Value.Date + TimeOfEntry.Value, EngagedState = SelectedState.Value });   _isMeterStarted = true; OnPropertyChanged(this,null); } And views communicate user actions like button clicks, tree view item selections, etc using commands. When user clicks on ‘Start the Meter’ button it invokes the method StartMeterCommand, which calls the method OnStartMeter which publishes the event to TotalViewModel using event aggregator  and TaxiStartedEvent. namespace TaxiModules.ViewModels { public class TotalViewModel:ObservableBase { ... private IEventAggregator _eventAggregator;   public TotalViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator;   InitializePropertyNames(); InitializeModel(); SubscribeToEvents(); }   public decimal? TotalFare { get { return _totalFare; } set { _totalFare = value; RaisePropertyChanged(_totalFarePropertyName); } } .... private void SubscribeToEvents() { _eventAggregator.GetEvent<TaxiStartedEvent>().Subscribe(OnTaxiStarted, ThreadOption.UIThread,false,(filter) => true); _eventAggregator.GetEvent<TaxiOnMoveEvent>().Subscribe(OnTaxiMove, ThreadOption.UIThread, false, (filter) => true); _eventAggregator.GetEvent<TaxiResetEvent>().Subscribe(OnTaxiReset, ThreadOption.UIThread, false, (filter) => true); }   private void OnTaxiStarted(TaxiStarted taxiStarted) { Fares.Add(new EntryFare()); Fares.Add(new StateTaxFare(taxiStarted)); Fares.Add(new NightSurchargeFare(taxiStarted)); Fares.Add(new PeakHourWeekdayFare(taxiStarted));   SetTotalFare(Fares); }   private void SetTotalFare(IEnumerable<IFare> fares) { TotalFare = (_totalFare ?? 0) + TaxiFareHelper.GetTotalFare(fares); } ....   } }   TotalViewModel subscribes to events, TaxiStartedEvent and rest. When TaxiStartedEvent gets invoked it calls the OnTaxiStarted method which sets the total fare which includes entry fee, state tax, nightly surcharge, peak hour weekday fare.   Note that TotalViewModel derives from ObservableBase which implements the method RaisePropertyChanged which we are invoking in Set of TotalFare property, i.e, once we update the TotalFare property it raises an the event that  allows the TotalFare text box to fetch the new value through the data context. ViewModel is communicating with View through data context and it has no knowledge about View, helping in loose coupling of ViewModel and View.   I have attached the source code (.Net 4.0, Prism 4.0, VS 2010) , download and play with it and don’t forget to leave your comments.  

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  • creating objects in list

    - by prince23
    List myList = new List { new Users{ Name="Kumar", Gender="M", Age=75, Parent="All"}, new Users{ Name="Suresh",Gender="M", Age=50, Parent="Kumar"}, new Users{ Name="Bennette", Gender="F",Age=45, Parent="Kumar"}, new Users{ Name="kian", Gender="M",Age=20, Parent="Suresh"}, new Users{ Name="Nathani", Gender="M",Age=15, Parent="Suresh"}, new Users{ Name="Peter", Gender="M",Age=90, Parent="All"}, new Users{ Name="Mica", Age=56, Gender="M",Parent="Peter"}, new Users{ Name="Linderman", Gender="M",Age=51, Parent="Peter"}, new Users{ Name="john", Age=25, Gender="M",Parent="Mica"}, new Users{ Name="tom", Gender="M",Age=21, Parent="Mica"}, new Users{ Name="Ando", Age=64, Gender="M",Parent="All"}, new Users{ Name="Maya", Age=24, Gender="M",Parent="Ando"}, new Users{ Name="Niki Sanders", Gender="F",Age=2, Parent="Maya"}, new Users{ Name="Angela Patrelli", Gender="F",Age=3, Parent="Maya"}, }; now i need to format the data like here i need to check the parent based on the parent i will be creating objects under the parent objects now { Name="Kumar", Gender="M", Age=75, Parent="All" } this is the top level as a property Parent ="all" now under parent object kumar here we again create a new object to store these information under object(kumar who is the parent) new Users{ Name="Suresh",Gender="M", Age=50, Parent="Kumar"}, new Users{ Name="Bennette", Gender="F",Age=45, Parent="Kumar"}, what i need to do here is i need to check the parent based on the parent create further objects under it ex: i need to achive like this. looking for the syntax how i can do it. public class SampleProjectData { public static ObservableCollection<Product> GetSampleData() { DateTime dtS = DateTime.Now; ObservableCollection<Product> teams = new ObservableCollection<Product>(); teams.Add(new Product() { PDName = "Product1", OverallStartTime = dtS, OverallEndTime = dtS + TimeSpan.FromDays(3), }); Project emp = new Project() { PName = "Project1", OverallStartTime = dtS + TimeSpan.FromDays(1), OverallEndTime = dtS + TimeSpan.FromDays(6) }; emp.Tasks.Add(new Task() { StartTime = dtS, EndTime = dtS + TimeSpan.FromDays(2), TaskName = "John's Task 3" }); emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(3), EndTime = dtS + TimeSpan.FromDays(4), TaskName = "John's Task 2" }); teams[0].Projects.Add(emp); emp = new Project() { PName = "Project2", OverallStartTime = dtS + TimeSpan.FromDays(1.5), OverallEndTime = dtS + TimeSpan.FromDays(5.5) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(1), EndTime = dtS + TimeSpan.FromDays(4), TaskName = "Victor's Task" }); teams[0].Projects.Add(emp); emp = new Project() { PName = "Project3", OverallStartTime = dtS + TimeSpan.FromDays(2), OverallEndTime = dtS + TimeSpan.FromDays(5) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(1), EndTime = dtS + TimeSpan.FromDays(4), TaskName = "Jason's Task 1" }); emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(7), EndTime = dtS + TimeSpan.FromDays(9), TaskName = "Jason's Task 2" }); teams[0].Projects.Add(emp); teams.Add(new Product() { PDName = "Product2", OverallStartTime = dtS, OverallEndTime = dtS + TimeSpan.FromDays(3) }); emp = new Project() { PName = "Project4", OverallStartTime = dtS + TimeSpan.FromDays(0.5), OverallEndTime = dtS + TimeSpan.FromDays(3.5) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(1.5), EndTime = dtS + TimeSpan.FromDays(4), TaskName = "Vicky's Task" }); teams[1].Projects.Add(emp); emp = new Project() { PName = "Project5", OverallStartTime = dtS + TimeSpan.FromDays(2), OverallEndTime = dtS + TimeSpan.FromDays(6) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(2.2), EndTime = dtS + TimeSpan.FromDays(3.8), TaskName = "Oleg's Task 1" }); emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(5), EndTime = dtS + TimeSpan.FromDays(6), TaskName = "Oleg's Task 2" }); emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(8), EndTime = dtS + TimeSpan.FromDays(9.6), TaskName = "Oleg's Task 3" }); teams[1].Projects.Add(emp); emp = new Project() { PName = "Project6", OverallStartTime = dtS + TimeSpan.FromDays(2.5), OverallEndTime = dtS + TimeSpan.FromDays(4.5) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(0.8), EndTime = dtS + TimeSpan.FromDays(2), TaskName = "Kim's Task" }); teams[1].Projects.Add(emp); teams.Add(new Product() { PDName = "Product3", OverallStartTime = dtS, OverallEndTime = dtS + TimeSpan.FromDays(3) }); emp = new Project() { PName = "Project7", OverallStartTime = dtS + TimeSpan.FromDays(5), OverallEndTime = dtS + TimeSpan.FromDays(7.5) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(1.5), EndTime = dtS + TimeSpan.FromDays(4), TaskName = "Balaji's Task 1" }); emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(5), EndTime = dtS + TimeSpan.FromDays(8), TaskName = "Balaji's Task 2" }); teams[2].Projects.Add(emp); emp = new Project() { PName = "Project8", OverallStartTime = dtS + TimeSpan.FromDays(3), OverallEndTime = dtS + TimeSpan.FromDays(6.3) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(1.75), EndTime = dtS + TimeSpan.FromDays(2.25), TaskName = "Li's Task" }); teams[2].Projects.Add(emp); emp = new Project() { PName = "Project9", OverallStartTime = dtS + TimeSpan.FromDays(2), OverallEndTime = dtS + TimeSpan.FromDays(6) }; emp.Tasks.Add(new Task() { StartTime = dtS + TimeSpan.FromDays(2), EndTime = dtS + TimeSpan.FromDays(3), TaskName = "Stacy's Task" }); teams[2].Projects.Add(emp); return teams; } } above is an sample data where i am grouping them with static data in the same way i need **to for teh data which is cmg from DB and i need to store them list** all these three data are comig from different services. and i am storing them in a list now i have three tables data Product , Project, Task. all the data are coming from webservies. i have created three list where i am storing the data in list. List<Project>objpro= new List<Project>(); List<Product>objproduct= new List<Product>(); LIst<Task>objTask= new List<Task>(); **now what i need to do is i need to do the mapping between these tables. if you see above. i have object of Product under Product i have added object of Project and then under project object i have added task object.** now from the above data which is stored in the list i need to do the same mapping between class. and group the data. public class Product : INotifyPropertyChanged { public Product() { this.Projects = new ObservableCollection<Project>(); } public string PDName { get; set; } public ObservableCollection<Project> Projects { get; set; } private DateTime _st; public DateTime OverallStartTime { get { return _st; } set { if (this._st != value) { TimeSpan dur = this._et - this._st; this._st = value; this.OnPropertyChanged("OverallStartTime"); this.OverallEndTime = value + dur; } } } private DateTime _et; public DateTime OverallEndTime { get { return _et; } set { if (this._et != value) { this._et = value; this.OnPropertyChanged("OverallEndTime"); } } } #region INotifyPropertyChanged Members protected void OnPropertyChanged(string name) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(name)); } public event PropertyChangedEventHandler PropertyChanged; #endregion } public class Project : INotifyPropertyChanged { public Project() { this.Tasks = new ObservableCollection<Task>(); } public string PName { get; set; } public ObservableCollection<Task> Tasks { get; set; } DateTime _st; public DateTime OverallStartTime { get { return _st; } set { if (this._st != value) { TimeSpan dur = this._et - this._st; this._st = value; this.OnPropertyChanged("OverallStartTime"); this.OverallEndTime = value + dur; } } } DateTime _et; public DateTime OverallEndTime { get { return _et; } set { if (this._et != value) { this._et = value; this.OnPropertyChanged("OverallEndTime"); } } } #region INotifyPropertyChanged Members protected void OnPropertyChanged(string name) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(name)); } public event PropertyChangedEventHandler PropertyChanged; #endregion } public class Task : INotifyPropertyChanged { public string TaskName { get; set; } DateTime _st; public DateTime StartTime { get { return _st; } set { if (this._st != value) { TimeSpan dur = this._et - this._st; this._st = value; this.OnPropertyChanged("StartTime"); this.EndTime = value + dur; } } } private DateTime _et; public DateTime EndTime { get { return _et; } set { if (this._et != value) { this._et = value; this.OnPropertyChanged("EndTime"); } } } #region INotifyPropertyChanged Members protected void OnPropertyChanged(string name) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(name)); } public event PropertyChangedEventHandler PropertyChanged; #endregion } hope my question is clear

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