Search Results

Search found 13788 results on 552 pages for 'instance'.

Page 58/552 | < Previous Page | 54 55 56 57 58 59 60 61 62 63 64 65  | Next Page >

  • GameplayScreen does not contain a definition for GraphicsDevice

    - by Dave Voyles
    Long story short: I'm trying to intergrate my game with Microsoft's Game State Management. In doing so I've run into some errors, and the latest one is in the title. I'm not able to display my HUD for the reasons listed above. Previously, I had much of my code in my Game.cs class, but the GSM has a bit of it in Game1, and most of what you have drawn for the main screen in your GameplayScreen class, and that is what is causing confusion on my part. I've created an instance of the GameplayScreen class to be used in the HUD class (as you can see below). Before integrating with the GSM however, I created an instance of my Game class, and all worked fine. It seems that I need to define my graphics device somewhere, but I am not sure of where exactly. I've left some code below to help you understand. public class GameStateManagementGame : Microsoft.Xna.Framework.Game { #region Fields GraphicsDeviceManager graphics; ScreenManager screenManager; // Creates a new intance, which is used in the HUD class public static Game Instance; // By preloading any assets used by UI rendering, we avoid framerate glitches // when they suddenly need to be loaded in the middle of a menu transition. static readonly string[] preloadAssets = { "gradient", }; #endregion #region Initialization /// <summary> /// The main game constructor. /// </summary> public GameStateManagementGame() { Content.RootDirectory = "Content"; graphics = new GraphicsDeviceManager(this); graphics.PreferredBackBufferWidth = 1280; graphics.PreferredBackBufferHeight = 720; graphics.IsFullScreen = false; graphics.ApplyChanges(); // Create the screen manager component. screenManager = new ScreenManager(this); Components.Add(screenManager); // Activate the first screens. screenManager.AddScreen(new BackgroundScreen(), null); //screenManager.AddScreen(new MainMenuScreen(), null); screenManager.AddScreen(new PressStartScreen(), null); } namespace Pong { public class HUD { public void Update(GameTime gameTime) { // Used in the Draw method titleSafeRectangle = new Rectangle (GameplayScreen.Instance.GraphicsDevice.Viewport.TitleSafeArea.X, GameplayScreen.Instance.GraphicsDevice.Viewport.TitleSafeArea.Y, GameplayScreen.Instance.GraphicsDevice.Viewport.TitleSafeArea.Width, GameplayScreen.Instance.GraphicsDevice.Viewport.TitleSafeArea.Height); } } } class GameplayScreen : GameScreen { #region Fields ContentManager content; public static GameStates gamestate; private GraphicsDeviceManager graphics; public int screenWidth; public int screenHeight; private Texture2D backgroundTexture; private SpriteBatch spriteBatch; private Menu menu; private SpriteFont arial; private HUD hud; Animation player; // Creates a new intance, which is used in the HUD class public static GameplayScreen Instance; public GameplayScreen() { TransitionOnTime = TimeSpan.FromSeconds(1.5); TransitionOffTime = TimeSpan.FromSeconds(0.5); } protected void Initialize() { lastScored = false; menu = new Menu(); resetTimer = 0; resetTimerInUse = true; ball = new Ball(content, new Vector2(screenWidth, screenHeight)); SetUpMulti(); input = new Input(); hud = new HUD(); // Places the powerup animation inside of the surrounding box // Needs to be cleaned up, instead of using hard pixel values player = new Animation(content.Load<Texture2D>(@"gfx/powerupSpriteSheet"), new Vector2(103, 44), 64, 64, 4, 5); // Used by for the Powerups random = new Random(); vec = new Vector2(100, 50); vec2 = new Vector2(100, 100); promptVec = new Vector2(50, 25); timer = 10000.0f; // Starting value for the cooldown for the powerup timer timerVector = new Vector2(10, 10); //JEP - one time creation of powerup objects playerOnePowerup = new Powerup(); playerOnePowerup.Activated += PowerupActivated; playerOnePowerup.Deactivated += PowerupDeactivated; playerTwoPowerup = new Powerup(); playerTwoPowerup.Activated += PowerupActivated; playerTwoPowerup.Deactivated += PowerupDeactivated; //JEP - moved from events since these only need set once activatedVec = new Vector2(100, 125); deactivatedVec = new Vector2(100, 150); powerupReady = false; }

    Read the article

  • Subterranean IL: The ThreadLocal type

    - by Simon Cooper
    I came across ThreadLocal<T> while I was researching ConcurrentBag. To look at it, it doesn't really make much sense. What's all those extra Cn classes doing in there? Why is there a GenericHolder<T,U,V,W> class? What's going on? However, digging deeper, it's a rather ingenious solution to a tricky problem. Thread statics Declaring that a variable is thread static, that is, values assigned and read from the field is specific to the thread doing the reading, is quite easy in .NET: [ThreadStatic] private static string s_ThreadStaticField; ThreadStaticAttribute is not a pseudo-custom attribute; it is compiled as a normal attribute, but the CLR has in-built magic, activated by that attribute, to redirect accesses to the field based on the executing thread's identity. TheadStaticAttribute provides a simple solution when you want to use a single field as thread-static. What if you want to create an arbitary number of thread static variables at runtime? Thread-static fields can only be declared, and are fixed, at compile time. Prior to .NET 4, you only had one solution - thread local data slots. This is a lesser-known function of Thread that has existed since .NET 1.1: LocalDataStoreSlot threadSlot = Thread.AllocateNamedDataSlot("slot1"); string value = "foo"; Thread.SetData(threadSlot, value); string gettedValue = (string)Thread.GetData(threadSlot); Each instance of LocalStoreDataSlot mediates access to a single slot, and each slot acts like a separate thread-static field. As you can see, using thread data slots is quite cumbersome. You need to keep track of LocalDataStoreSlot objects, it's not obvious how instances of LocalDataStoreSlot correspond to individual thread-static variables, and it's not type safe. It's also relatively slow and complicated; the internal implementation consists of a whole series of classes hanging off a single thread-static field in Thread itself, using various arrays, lists, and locks for synchronization. ThreadLocal<T> is far simpler and easier to use. ThreadLocal ThreadLocal provides an abstraction around thread-static fields that allows it to be used just like any other class; it can be used as a replacement for a thread-static field, it can be used in a List<ThreadLocal<T>>, you can create as many as you need at runtime. So what does it do? It can't just have an instance-specific thread-static field, because thread-static fields have to be declared as static, and so shared between all instances of the declaring type. There's something else going on here. The values stored in instances of ThreadLocal<T> are stored in instantiations of the GenericHolder<T,U,V,W> class, which contains a single ThreadStatic field (s_value) to store the actual value. This class is then instantiated with various combinations of the Cn types for generic arguments. In .NET, each separate instantiation of a generic type has its own static state. For example, GenericHolder<int,C0,C1,C2> has a completely separate s_value field to GenericHolder<int,C1,C14,C1>. This feature is (ab)used by ThreadLocal to emulate instance thread-static fields. Every time an instance of ThreadLocal is constructed, it is assigned a unique number from the static s_currentTypeId field using Interlocked.Increment, in the FindNextTypeIndex method. The hexadecimal representation of that number then defines the specific Cn types that instantiates the GenericHolder class. That instantiation is therefore 'owned' by that instance of ThreadLocal. This gives each instance of ThreadLocal its own ThreadStatic field through a specific unique instantiation of the GenericHolder class. Although GenericHolder has four type variables, the first one is always instantiated to the type stored in the ThreadLocal<T>. This gives three free type variables, each of which can be instantiated to one of 16 types (C0 to C15). This puts an upper limit of 4096 (163) on the number of ThreadLocal<T> instances that can be created for each value of T. That is, there can be a maximum of 4096 instances of ThreadLocal<string>, and separately a maximum of 4096 instances of ThreadLocal<object>, etc. However, there is an upper limit of 16384 enforced on the total number of ThreadLocal instances in the AppDomain. This is to stop too much memory being used by thousands of instantiations of GenericHolder<T,U,V,W>, as once a type is loaded into an AppDomain it cannot be unloaded, and will continue to sit there taking up memory until the AppDomain is unloaded. The total number of ThreadLocal instances created is tracked by the ThreadLocalGlobalCounter class. So what happens when either limit is reached? Firstly, to try and stop this limit being reached, it recycles GenericHolder type indexes of ThreadLocal instances that get disposed using the s_availableIndices concurrent stack. This allows GenericHolder instantiations of disposed ThreadLocal instances to be re-used. But if there aren't any available instantiations, then ThreadLocal falls back on a standard thread local slot using TLSHolder. This makes it very important to dispose of your ThreadLocal instances if you'll be using lots of them, so the type instantiations can be recycled. The previous way of creating arbitary thread-static variables, thread data slots, was slow, clunky, and hard to use. In comparison, ThreadLocal can be used just like any other type, and each instance appears from the outside to be a non-static thread-static variable. It does this by using the CLR type system to assign each instance of ThreadLocal its own instantiated type containing a thread-static field, and so delegating a lot of the bookkeeping that thread data slots had to do to the CLR type system itself! That's a very clever use of the CLR type system.

    Read the article

  • Designing An ACL Based Permission System

    - by ryanzec
    I am trying to create a permissions system where everything is going to be stored in MySQL (or some database) and pulled using PHP for a project management system I am building.  I am right now trying to do it is an ACL kind of way.  There are a number key features I want to be able to support: 1.  Being able to assign permissions without being tied to a specific object. The reason for this is that I want to be able to selectively show/hide elements of the UI based on permissions at a point where I am not directly looking at a domain object instance.  For instance, a button to create a new project should only should only be shown to users that have the pm.project.create permission but obviously you can assign a create permission to an domain object instance (as it is already created). 2.  Not have to assign permissions for every single object. Obviously creating permissions entries for every single object (projects, tickets, comments, etc…) would become a nightmare to maintain so I want to have some level of permission inheritance. *3.  Be able to filter queries based on permissions. This would be a really nice to have but I am not sure if it is possible.  What I mean by this is say I have a page that list all projects.  I want the query that pulls all projects to incorporate the ACL so that it would not show projects that the current user does not have pm.project.read access to.  This would have to be incorporated into the main query as if it is a process that is done after that main query (which I know I could do) certain features like pagination become much more difficult. Right now this is my basic design for the tables: AclEntities id - the primary key key - the unique identifier for the domain object (usually the primary key of that object) parentId - the parent of the domain object (like the project object if this was a ticket object) aclDomainObjectId - metadata about the domain object AclDomainObjects id - primary key title - simple string to unique identify the domain object(ie. project, ticket, comment, etc…) fullyQualifiedClassName - the fully qualified class name for use in code (I am using namespaces) There would also be tables mapping AclEntities to Users and UserGroups. I also have this interface that all acl entity based object have to implement: IAclEntity getAclKey() - to the the unique key for this specific instance of the acl domain object (generally return the primary key or a concatenated string of a composite primary key) getAclTitle() - to get the unique title for the domain object (generally just returning a static string) getAclDisplayString() - get the string that represents this entity (generally one or more field on the object) getAclParentEntity() - get the parent acl entity object (or null if no parent) getAclEntity() - get the acl enitty object for this instance of the domain object (or null if one has not been created yet) hasPermission($permissionString, $user = null) - whether or not the user has the permission for this instance of the domain object static getFromAclEntityId($aclEntityId) - get a specific instance of the domain object from an acl entity id. Do any of these features I am looking for seems hard to support or are just way off base? Am I missing or not taking in account anything in my implementation? Is performance something I should keep in mind?

    Read the article

  • Accessing SQL with the PC name not the IP

    - by Cornelius
    I'm trying to connect to a SQL instance (default instance) on a machine. When using the IP of the machine it connects to the machine. Using the name of the machine on that machine you are able to establish a connection to the SQL instance but using the machine name on another PC the connection cannot be established. And gives the error A network-related or instance-specific error occurred while establishing a connection to SQL Server. ... (Microsoft Server, Error: 10060) The machine that I am trying to establish the connection from can ping the machine with the SQL instance both on the IP and on the name. Why would this be and how can I fix it? Edit: pinging the name does resolve the correct IP. Pinging the FQDN also works correctly.

    Read the article

  • Why is nesting or piggybacking errors within errors bad in general?

    - by dietbuddha
    Why is nesting or piggybacking errors within errors bad in general? To me it seems bad intuitively, but I'm suspicious in that I cannot adequately articulate why it is bad. This may be because it is not in general bad and that it is only bad in specific instances. Why is it detrimental to design error/exception handling in such a way. The specific instance is that of a REST service. There is a desire by some to use http errors (specifically the 500 response) as a way to indicate any problem with specific instances of a resource. An example of an instance resource in this case would be: http://server/ticket/80 # instance http://server/ticket # not an instance So this is the behavior that is being proposed. If ticket 80 does not exist return a http response code of 500. Within the body of the error return the "real" error as an additional error code and description. If the ticket resource doesn't exist return a response code of 404.

    Read the article

  • Unable to Call Instantiate in Class Member Function

    - by onguarde
    The following javascript is attached to a gameObject. var instance : GameObject; class eg_class { function eg_func(){ var thePrefab : GameObject; instance = Instantiate(thePrefab); } } Error, Unknown identifier: 'instance'. Unknown identifier: 'Instantiate'. Questions, 1) Why is it that "instance" cannot be accessed within a class? Isn't it supposed to be a public variable? 2) "Instantiate" function works in Start()/Update() root functions. Is there a way to make it work from within member functions? Thanks in advance!

    Read the article

  • Windows Virtual PC File Copy from host very slow

    - by Shiv Kumar
    I have a Windows 7 desktop on which I've installed Windows Virtual PC and an instance Windows 7. I also have virtual XP instance on the same host. The problem I am having is that copying files from the host to the virtual machine is dog slow. I'm talking 17KB/sec. The host machine has a gigbit NIC. While using the XP virtual instance to do the same I didn't notice a huge difference but on the Window 7 virtual instance the time is really slowing me down. Is there something I need to do (settings) to fix this? I've attached an image of the Resource monitor (of the virtual Windows 7 instance) that shows my network traffic going in bursts rather than relatively steady. The files are on a "public" folder on my host machine.

    Read the article

  • Passing multiple sets of arguments to a command

    - by Alec
    instances contains several whitespace separated strings, as does snapshots. I want to run the command below, with each instance-snapshot pair. ec2-attach-volume --instance $instances --device /dev/sdf $snapshots For example, if instances contains A B C, and snapshots contains 1 2 3, I want the command to be called like so: ec2-attach-volume -C cert.pem -K pk.pem --instance A --device /dev/sdf 1 ec2-attach-volume -C cert.pem -K pk.pem --instance B --device /dev/sdf 2 ec2-attach-volume -C cert.pem -K pk.pem --instance C --device /dev/sdf 3 I can do either one or the other with xargs -n 1, but how do I do both?

    Read the article

  • How to name a static factory method in the utility class?

    - by leventov
    I have an interface MyLongNameInterface with a counterpart utility class MyLongNameInterfaces. What is the best name for a static factory method in the utility class, which creates an instance of MyLongNameInterface? MyLongNameInterfaces.newInstance() -- a new instance of the utility class? MyLongNameInterfaces.newMyLongNameInterface() -- too verbose MyLongNameInterfaces.create() -- create an instance of the utility class? Also, create is not a widely used conventional verb in Java better option?

    Read the article

  • What to do with DATETIMEOFFSET?

    - by GavinPayneUK
    Someone asked me today if the time zone of a specific instance of SQL Server could be changed to match the country which that instance served. Some database products allow you to set this at an engine level which made me wonder if your data’s time fields “move” with the time zone setting of the database server instance?  If something was logged as happening at 9am Paris time it happened then, if I change my database server parameters did that event now happen at 9am New York time?  Perhaps...(read more)

    Read the article

  • Amazon - install a complete server on EBS

    - by user1169575
    is it possible to install a full working OS with a webserver, db, and all needed stuff on an EBS storage? If so, would I immediatly gain benefits by mounting this EBS on a better instance? Otherwise (if I cannot install a complete image, or if you don't think it's reasonable) can I install the software so that I only need to mount the EBS on a new instance to have it working? I purchased a Medium Reserved Instance, but when there will be the need to get a better instance I'd like to move the whole db/website, I'd simply buy a better instance and then attach the EBS. Is it possibile? I'm imaging about it like an hard drive that would be mounted on a better server. Of course, more RAM would allow me to increase caching limits, and that's ok, but I don't want to reinstall anything (the main website is a magentocommerce and it's pretty painful to move it). P.S. is the Standard EBS (100 IOPS) valid or do I need to choose a Provisioned IOPS (up to 1000 IOPS)?

    Read the article

  • Use Amazon EC2 as a backup server

    - by MikeMurko
    I would like to use Amazon EC2 as an emergency backup database+web server in the event our primary host becomes unavailable. I feel like I wouldn't have trouble setting up a Windows instance, install SQL Server and get the web server up and running (would take a few hours, plus installing various libraries, our source code, etc). My question relates to pricing. If I simply "stop" the instance rather than "terminate" it, does that stop counting "instance-hours"? I would prefer not to terminate the instance and lose all that work I spent setting it up. If I must "terminate" in order to stop the billing - is it possible to make an image of the server after I have set it all up, then save that image somewhere (S3?) Is this something that people do regularly? Ideally this instance would just be waiting in the wings for an issue with our host, but costing us nothing except perhaps data storage costs.

    Read the article

  • Is the Observer pattern adequate for this kind of scenario?

    - by Omega
    I'm creating a simple game development framework with Ruby. There is a node system. A node is a game entity, and it has position. It can have children nodes (and one parent node). Children are always drawn relatively to their parent. Nodes have a @position field. Anyone can modify it. When such position is modified, the node must update its children accordingly to properly draw them relatively to it. @position contains a Point instance (a class with x and y properties, plus some other useful methods). I need to know when a node's @position's state changes, so I can tell the node to update its children. This is easy if the programmer does something like this: @node.position = Point.new(300,300) Because it is equivalent to calling this: # Code in the Node class def position=(newValue) @position = newValue update_my_children # <--- I know that the position changed end But, I'm lost when this happens: @node.position.x = 300 The only one that knows that the position changed is the Point instance stored in the @position property of the node. But I need the node to be notified! It was at this point that I considered the Observer pattern. Basically, Point is now observable. When a node's position property is given a new Point instance (through the assignment operator), it will stop observing the previous Point it had (if any), and start observing the new one. When a Point instance gets a state change, all observers (the node owning it) will be notified, so now my node can update its children when the position changes. A problem is when this happens: @someNode.position = @anotherNode.position This means that two nodes are observing the same point. If I change one of the node's position, the other would change as well. To fix this, when a position is assigned, I plan to create a new Point instance, copy the passed argument's x and y, and store my newly created point instead of storing the passed one. Another problem I fear is this: somePoint = @node.position somePoint.x = 500 This would, technically, modify @node's position. I'm not sure if anyone would be expecting that behavior. I'm under the impression that people see Point as some kind of primitive rather than an actual object. Is this approach even reasonable? Reasons I'm feeling skeptical: I've heard that the Observer pattern should be used with, well, many observers. Technically, in this scenario there is only one observer at a time. When assigning a node's position as another's (@someNode.position = @anotherNode.position), where I create a whole new instance rather than storing the passed point, it feels hackish, or even inefficient.

    Read the article

  • How to setup matlabpool for multiple processors?

    - by JohnIdol
    I just setup a Extra Large Heavy Computation EC2 instance to throw it at my Genetic Algorithms problem, hoping to speed up things. This instance has 8 Intel Xeon processors (around 2.4Ghz each) and 7 Gigs of RAM. On my machine I have an Intel Core Duo, and matlab is able to work with my two cores just fine by runinng: matlabpool open 2 On the EC2 instance though, matlab only is capable of detecting 1 out of 8 processors, and if I try running: matlabpool open 8 I get an error saying that the ClusterSize is 1 since there's only 1 core on my CPU. True, there is only 1 core on each CPU, but I have 8 CPUs on the given EC2 instance! So the difference from my machine and the ec2 instance is that I have my 2 cores on a single processor locally, while the EC2 instance has 8 distinct processors. My question is, how do I get matlab to work with those 8 processors? I found this paper, but it seems related to setting up matlab with multiple EC2 instances (not related to multiple processors on the same instance, EC2 or not), which is not my problem. Any help appreciated!

    Read the article

  • How to create a rails staging environment in engineyard?

    - by siulamvictor
    I have a production instance in engineyard up and running well. I would like to create a new staging instance for internal testing. I cloned the existing production instance, changed Framework Environment to staging. I can deploy all the code to staging instance from Github. Engineyard reported the server is fully configured and ready. I have subdomain-fu in my Rails app, as I have some subdomain handling in my app. I set the subdomain initializer like this.... SubdomainFu.tld_sizes = {:development => 1, :test => 0, :production => 1, :staging => 2} As the production instance is using the domain xxxxx.com, I would like my staging instance use the domain staging.xxxxx.com. But I got an error when open this domain. Seems the app use xxxxx.com as domain but not the staging.xxxxx.com. I checked the engineyard database.yml. It use xxxxx_production database, I supposed it should be xxxxx_staging. Seems the engineyard instance is not set to staging environment, but just clone all the setting from production server. Does anyone have experience with this and can show me the way on how to fix it? Thanks. :)

    Read the article

  • PHP Multiple Calls to Server Share Objects?

    - by user1513171
    I’m wondering this about PHP on Apache. Do multiple calls to the server from different users—could be sitting next to each other, in different states, different countries, etc…—share memory? For example, if I create a static variable in a PHP script and set it to 1 by default, then user1 comes in and it changes to 2, and then almost at the exactly same time, user2 comes in, does he see that static variable with a value of 1 or 2? An even better example is this class I have in PHP: class ApplicationRegistry { private static $instance; private static $PDO; private function __construct() { self::$PDO = $db = new \PDO('mysql:unix_socket=/........'); self::$PDO->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION); } static function instance() { if(!isset(self::$instance)) { self::$instance = new self(); } return self::$instance; } static function getDSN() { if(!isset(self::$PDO)) { self::instance(); return self::$PDO; } return self::$PDO; } } So this is a Singleton that has a static PDO instance. If user1 and user2 are hitting the server at the exact same time are they using different instances of PDO or are they using the same one? This is a confusing concept for me and I'm trying to think of how my application will scale.

    Read the article

  • Python metaclass for enforcing immutability of custom types

    - by Mark Lehmacher
    Having searched for a way to enforce immutability of custom types and not having found a satisfactory answer I came up with my own shot at a solution in form of a metaclass: class ImmutableTypeException( Exception ): pass class Immutable( type ): ''' Enforce some aspects of the immutability contract for new-style classes: - attributes must not be created, modified or deleted after object construction - immutable types must implement __eq__ and __hash__ ''' def __new__( meta, classname, bases, classDict ): instance = type.__new__( meta, classname, bases, classDict ) # Make sure __eq__ and __hash__ have been implemented by the immutable type. # In the case of __hash__ also make sure the object default implementation has been overridden. # TODO: the check for eq and hash functions could probably be done more directly and thus more efficiently # (hasattr does not seem to traverse the type hierarchy) if not '__eq__' in dir( instance ): raise ImmutableTypeException( 'Immutable types must implement __eq__.' ) if not '__hash__' in dir( instance ): raise ImmutableTypeException( 'Immutable types must implement __hash__.' ) if _methodFromObjectType( instance.__hash__ ): raise ImmutableTypeException( 'Immutable types must override object.__hash__.' ) instance.__setattr__ = _setattr instance.__delattr__ = _delattr return instance def __call__( self, *args, **kwargs ): obj = type.__call__( self, *args, **kwargs ) obj.__immutable__ = True return obj def _setattr( self, attr, value ): if '__immutable__' in self.__dict__ and self.__immutable__: raise AttributeError( "'%s' must not be modified because '%s' is immutable" % ( attr, self ) ) object.__setattr__( self, attr, value ) def _delattr( self, attr ): raise AttributeError( "'%s' must not be deleted because '%s' is immutable" % ( attr, self ) ) def _methodFromObjectType( method ): ''' Return True if the given method has been defined by object, False otherwise. ''' try: # TODO: Are we exploiting an implementation detail here? Find better solution! return isinstance( method.__objclass__, object ) except: return False However, while the general approach seems to be working rather well there are still some iffy implementation details (also see TODO comments in code): How do I check if a particular method has been implemented anywhere in the type hierarchy? How do I check which type is the origin of a method declaration (i.e. as part of which type a method has been defined)?

    Read the article

  • convincing C# compiler that execution will stop after a member returns

    - by Sarah Vessels
    I don't think this is currently possible or if it's even a good idea, but it's something I was thinking about just now. I use MSTest for unit testing my C# project. In one of my tests, I do the following: MyClass instance; try { instance = getValue(); } catch (MyException ex) { Assert.Fail("Caught MyException"); } instance.doStuff(); // Use of unassigned local variable 'instance' To make this code compile, I have to assign a value to instance either at its declaration or in the catch block. However, Assert.Fail will never, to the best of my knowledge, allow execution to proceed past it, hence instance will never be used without a value. Why is it then that I must assign a value to it? If I change the Assert.Fail to something like throw ex, the code compiles fine, I assume because it knows that exception will disallow execution to proceed to a point where instance would be used uninitialized. So is it a case of runtime versus compile-time knowledge about where execution will be allowed to proceed? Would it ever be reasonable for C# to have some way of saying that a member, in this case Assert.Fail, will never allow execution after it returns? Maybe that could be in the form of a method attribute. Would this be useful or an unnecessary complexity for the compiler?

    Read the article

  • Importing into a Exported object with MEF

    - by Nathan W
    I'm sorry if this question has already been asked 100 times, but I'm really struggling to get it to work. Say I have have three projects. Core.dll Has common interfaces Shell.exe Loads all modules in assembly folder. References Core.dll ModuleA.dll Exports Name, Version of module. References Core.dll Shell.exe has a [Export] that contains an single instance of a third party application that I need to inject into all loaded modules. So far the code that I have in Shell.exe is: static void Main(string[] args) { ThirdPartyApp map = new ThirdPartyApp(); var ad = new AssemblyCatalog(Assembly.GetExecutingAssembly()); var dircatalog = new DirectoryCatalog("."); var a = new AggregateCatalog(dircatalog, ad); // Not to sure what to do here. } class Test { [Export(typeof(ThirdPartyApp))] public ThirdPartyApp Instance { get; set; } [Import(typeof(IModule))] public IModule Module { get; set; } } I need to create a instance of Test, and load Instance with map from the Main method then load the Module from ModuleA.dll that is in the executing directory then [Import] Instance into the loaded module. In ModuleA I have a class like this: [Export(IModule)] class Module : IModule { [Import(ThirdPartyApp)] public ThirdPartyApp Instance {get;set;} } I know I'm half way there I just don't know how to put it all together, mainly with loading up test with a instance of map from Main. Could anyone help me with this.

    Read the article

  • Request-local storage in ASP.NET (accessible to the code from IHttpModule implementation)

    - by IgorK
    I need to have some object hanging around between two events I'm interested in: PreRequestHandlerExecute (where I create an instance of my object and want to save it) and PostRequestHandlerExecute (where I want to get to the object). After the second event the object is not needed for my purposes and should be discarded either by storage or my explicit action. So the ideal context where my object should be stored is per request (with guaranteed no sharing issues when different threads are serving requests... or processes/servers :) ) Take into account that actual implementation I can do is being made from a HttpModule and is supposed to be a pluggable solution for already written web apps (so the option to provide some state using static/instance variables in Global.asax doesn't look good - I will have to modify Global.asax on every web application). Cache seems to be too broad for this use. I tried to see whether httpContext.Application (of type HttpApplicationState) is good for me or not, but cannot get whether it is exactly per HttpApplication instance or not (AFAIK you can have several instances of HttpApplications used on different threads and therefore serving several requests simultaneously - then using storage shared between threads will not work correctly; otherwise I would use it because one HttpApplication instance serves exactly one request at a time). Something could be done with storing state on the HttpModule instances if I know for sure that it's exactly bound 1-to-1 with every HttpApplication instance running (but again I need a proof that HttpApplication instance is 1-to-1 with my HttpModule's instance). Any valuable and reputable links on these topics are much appreciated... Would be great to find something particularly well-suited for per request situation (because otherwise I may end up with something ulgy... probably either some 'broader' scoped storage and some hacks to have different keys in the storage for different requests, OR using a thread-local thing and in this way commit to the theory that IIS/ASP.NET will not ever serve first event from one thread and the second event from the other thread and so on)

    Read the article

  • FF extension: saving a value in preferences and retrieving in the js file

    - by encryptor
    I am making an extension which should take a link as the user input only once. Then the entire extension keeps using that link on various functions in the JS file. When the user changes it, the value accessed by the js file also changes accordingly. I am using the following but it does not work for me var pref_manager = Components.classes["@mozilla.org/preferencesservice;1"].getService(Components.interfaces.nsIPrefService) function setInstance(){ if (pref_manager.prefHasUserValue("myvar")) { instance = pref_manager.getString("myvar"); alert(instance); } if(instance == null){ instance = prompt("Please enter webcenter host and port"); // Setting the value pref_manager.setString("myvar", instance); } } instance is the global variable in which i take the user input. The alert (instance) does not show up, which means there is some problem by the way i am saving the pref or extracting it. Can someone please help me with this. I have never worked with preferences before. so even if there are minor problems i might not be able to figure out.

    Read the article

  • Help to edit the Recent Posts Wordpress widget to diplay in all 3 languages at once

    - by CreativEliza
    Site link: http://nuestrafrontera.org/wordpress/ I want the feed of recent post titles to show in the sidebar for all 3 languages, separated by language. So, for example, under Recent Posts the sidebar would have "English" and then the latest 3 posts in English, then "Español" and the latest 3 in Spanish and then French. All in a list in the column and appearing on all pages with the sidebar in all languages. I am using the most current version of Wordpress with the WPML plugin. I believe the Wordpress widget for Recent Posts needs to be tweaked to do this. Here is the code (from wp-includes/default-widgets.php): class WP_Widget_Recent_Posts extends WP_Widget { function WP_Widget_Recent_Posts() { $widget_ops = array('classname' => 'widget_recent_entries', 'description' => __( "The most recent posts on your blog") ); $this->WP_Widget('recent-posts', __('Recent Posts'), $widget_ops); $this->alt_option_name = 'widget_recent_entries'; add_action( 'save_post', array(&$this, 'flush_widget_cache') ); add_action( 'deleted_post', array(&$this, 'flush_widget_cache') ); add_action( 'switch_theme', array(&$this, 'flush_widget_cache') ); } function widget($args, $instance) { $cache = wp_cache_get('widget_recent_posts', 'widget'); if ( !is_array($cache) ) $cache = array(); if ( isset($cache[$args['widget_id']]) ) { echo $cache[$args['widget_id']]; return; } ob_start(); extract($args); $title = apply_filters('widget_title', empty($instance['title']) ? __('Recent Posts') : $instance['title']); if ( !$number = (int) $instance['number'] ) $number = 10; else if ( $number < 1 ) $number = 1; else if ( $number > 15 ) $number = 15; $r = new WP_Query(array('showposts' => $number, 'nopaging' => 0, 'post_status' => 'publish', 'caller_get_posts' => 1)); if ($r->have_posts()) : ?> <?php echo $before_widget; ?> <?php if ( $title ) echo $before_title . $title . $after_title; ?> <ul> <?php while ($r->have_posts()) : $r->the_post(); ?> <li><a href="<?php the_permalink() ?>" title="<?php echo esc_attr(get_the_title() ? get_the_title() : get_the_ID()); ?>"><?php if ( get_the_title() ) the_title(); else the_ID(); ?> </a></li> <?php endwhile; ?> </ul> <?php echo $after_widget; ?> <?php wp_reset_query(); // Restore global post data stomped by the_post(). endif; $cache[$args['widget_id']] = ob_get_flush(); wp_cache_add('widget_recent_posts', $cache, 'widget'); } function update( $new_instance, $old_instance ) { $instance = $old_instance; $instance['title'] = strip_tags($new_instance['title']); $instance['number'] = (int) $new_instance['number']; $this->flush_widget_cache(); $alloptions = wp_cache_get( 'alloptions', 'options' ); if ( isset($alloptions['widget_recent_entries']) ) delete_option('widget_recent_entries'); return $instance; } function flush_widget_cache() { wp_cache_delete('widget_recent_posts', 'widget'); } function form( $instance ) { $title = esc_attr($instance['title']); if ( !$number = (int) $instance['number'] ) $number = 5; ?> <p><label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title:'); ?></label> <input class="widefat" id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo $this->get_field_name('title'); ?>" type="text" value="<?php echo $title; ?>" /></p> <p><label for="<?php echo $this->get_field_id('number'); ?>"><?php _e('Number of posts to show:'); ?></label> <input id="<?php echo $this->get_field_id('number'); ?>" name="<?php echo $this->get_field_name('number'); ?>" type="text" value="<?php echo $number; ?>" size="3" /><br /> <small><?php _e('(at most 15)'); ?></small></p> <?php } }

    Read the article

  • Why does decorating a class break the descriptor protocol, thus preventing staticmethod objects from behaving as expected?

    - by Robru
    I need a little bit of help understanding the subtleties of the descriptor protocol in Python, as it relates specifically to the behavior of staticmethod objects. I'll start with a trivial example, and then iteratively expand it, examining it's behavior at each step: class Stub: @staticmethod def do_things(): """Call this like Stub.do_things(), with no arguments or instance.""" print "Doing things!" At this point, this behaves as expected, but what's going on here is a bit subtle: When you call Stub.do_things(), you are not invoking do_things directly. Instead, Stub.do_things refers to a staticmethod instance, which has wrapped the function we want up inside it's own descriptor protocol such that you are actually invoking staticmethod.__get__, which first returns the function that we want, and then gets called afterwards. >>> Stub <class __main__.Stub at 0x...> >>> Stub.do_things <function do_things at 0x...> >>> Stub.__dict__['do_things'] <staticmethod object at 0x...> >>> Stub.do_things() Doing things! So far so good. Next, I need to wrap the class in a decorator that will be used to customize class instantiation -- the decorator will determine whether to allow new instantiations or provide cached instances: def deco(cls): def factory(*args, **kwargs): # pretend there is some logic here determining # whether to make a new instance or not return cls(*args, **kwargs) return factory @deco class Stub: @staticmethod def do_things(): """Call this like Stub.do_things(), with no arguments or instance.""" print "Doing things!" Now, naturally this part as-is would be expected to break staticmethods, because the class is now hidden behind it's decorator, ie, Stub not a class at all, but an instance of factory that is able to produce instances of Stub when you call it. Indeed: >>> Stub <function factory at 0x...> >>> Stub.do_things Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'function' object has no attribute 'do_things' >>> Stub() <__main__.Stub instance at 0x...> >>> Stub().do_things <function do_things at 0x...> >>> Stub().do_things() Doing things! So far I understand what's happening here. My goal is to restore the ability for staticmethods to function as you would expect them to, even though the class is wrapped. As luck would have it, the Python stdlib includes something called functools, which provides some tools just for this purpose, ie, making functions behave more like other functions that they wrap. So I change my decorator to look like this: def deco(cls): @functools.wraps(cls) def factory(*args, **kwargs): # pretend there is some logic here determining # whether to make a new instance or not return cls(*args, **kwargs) return factory Now, things start to get interesting: >>> Stub <function Stub at 0x...> >>> Stub.do_things <staticmethod object at 0x...> >>> Stub.do_things() Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: 'staticmethod' object is not callable >>> Stub() <__main__.Stub instance at 0x...> >>> Stub().do_things <function do_things at 0x...> >>> Stub().do_things() Doing things! Wait.... what? functools copies the staticmethod over to the wrapping function, but it's not callable? Why not? What did I miss here? I was playing around with this for a bit and I actually came up with my own reimplementation of staticmethod that allows it to function in this situation, but I don't really understand why it was necessary or if this is even the best solution to this problem. Here's the complete example: class staticmethod(object): """Make @staticmethods play nice with decorated classes.""" def __init__(self, func): self.func = func def __call__(self, *args, **kwargs): """Provide the expected behavior inside decorated classes.""" return self.func(*args, **kwargs) def __get__(self, obj, objtype=None): """Re-implement the standard behavior for undecorated classes.""" return self.func def deco(cls): @functools.wraps(cls) def factory(*args, **kwargs): # pretend there is some logic here determining # whether to make a new instance or not return cls(*args, **kwargs) return factory @deco class Stub: @staticmethod def do_things(): """Call this like Stub.do_things(), with no arguments or instance.""" print "Doing things!" Indeed it works exactly as expected: >>> Stub <function Stub at 0x...> >>> Stub.do_things <__main__.staticmethod object at 0x...> >>> Stub.do_things() Doing things! >>> Stub() <__main__.Stub instance at 0x...> >>> Stub().do_things <function do_things at 0x...> >>> Stub().do_things() Doing things! What approach would you take to make a staticmethod behave as expected inside a decorated class? Is this the best way? Why doesn't the builtin staticmethod implement __call__ on it's own in order for this to just work without any fuss? Thanks.

    Read the article

  • Intermittent Windows Server 2008 BSOD and restart

    - by Timka
    Our EC2 Instance (Windows Server 2008) crashed multiple times for the past 3 months (last time was today at 1:05 EST). Upon reviewing MEMORY.DMP file we noticed that possible cause of the crashes is rhelnet.sys (RedHat PV NIC Driver). Server's Event Viewer has the following records right after the crash: Critical - Kernel Power: The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly. BugCheck: The computer has rebooted from a bugcheck. The bugcheck was: 0x000000d1 (0x000000000000002d, 0x0000000000000002, 0x0000000000000000, 0xfffff88001402d14). A dump was saved in: C:\Windows\MEMORY.DMP. Report Id: 100113-35849-01. Could this be a hardware issue? Would it help if we stop and start the instance? Or is this more likely that this is caused by the software running on the system? [Update 10.01.2013] Amazon Rep suggested to update RH drivers to Citrix PV drivers on our instance: Upgrading PV Drivers [Update 10.08.2013] We performed a drivers upgrade on the cloned instance. Right after the upgrade we noticed the following errors in our Event viewer: Xennet6 errors in Event Viewer (Event ID# 5001) After digging a bit more I found this article suggesting to install the latest Citrix drivers. Unfortunately, this didn't help us at all and our cloned instance became unresponsive. [Update 10.08.2013 2] I recreated an instance and updated PV drivers again. After searching on Internet I found this article where Amazon Rep explains that: "Event ID 5001 from source Xennet6 cannot be found" message does not indicate anything wrong, just that the PV driver is looking for a feature that we have not implemented in our version of Xen. I will keep my test system running for a while to see if there any issues with it.

    Read the article

< Previous Page | 54 55 56 57 58 59 60 61 62 63 64 65  | Next Page >