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  • Weak event handler model for use with lambdas

    - by Benjol
    OK, so this is more of an answer than a question, but after asking this question, and pulling together the various bits from Dustin Campbell, Egor, and also one last tip from the 'IObservable/Rx/Reactive framework', I think I've worked out a workable solution for this particular problem. It may be completely superseded by IObservable/Rx/Reactive framework, but only experience will show that. I've deliberately created a new question, to give me space to explain how I got to this solution, as it may not be immediately obvious. There are many related questions, most telling you you can't use inline lambdas if you want to be able to detach them later: Weak events in .Net? Unhooking events with lambdas in C# Can using lambdas as event handlers cause a memory leak? How to unsubscribe from an event which uses a lambda expression? Unsubscribe anonymous method in C# And it is true that if YOU want to be able to detach them later, you need to keep a reference to your lambda. However, if you just want the event handler to detach itself when your subscriber falls out of scope, this answer is for you.

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  • jquery image hover popup cant detect browser edge and change its direction

    - by Salman
    hi guys i am trying to implement jquery image hover popup but facing a problem when the popup is closer to browser edge it goes beyond its edge i want it to change its direction when it finds that space is not enough to show that popup, i have see this effect in many plugins where popups, tooltips and drop down menus change their direction if they are close to browser window edge can any one guide me in right direction here is the screen shot for reference http://img512.imageshack.us/img512/4990/browseredge.png here is the jquery hover code function imagePreview(){ /* CONFIG */ xOffset = 10; yOffset = 30; // these 2 variable determine popup's distance from the cursor // you might want to adjust to get the right result /* END CONFIG */ $("a.preview").hover(function(e){ this.t = this.title; this.title = ""; var c = (this.t != "") ? "<br>" + this.t : ""; var newName = this.name; //console.log(this.name); newName=newName.replace("/l/","/o/"); //console.log(newName); $("body").append("<p id='preview'><img src='"+ this.name +"' alt='Image preview' style='margin-bottom:5px;'>"+ c +"</p>"); $("#preview img").error(function () { $("#preview img").attr("src" ,newName).css({'width': '400px', 'height': 'auto'}); }); $("#preview") .css("top",(e.pageY - xOffset) + "px") .css("left",(e.pageX + yOffset) + "px") .fadeIn("fast"); }, function(){ this.title = this.t; $("#preview").remove(); }); $("a.preview").mousemove(function(e){ $("#preview") .css("top",(e.pageY - xOffset) + "px") .css("left",(e.pageX + yOffset) + "px"); }); }; any help will be appriciated Thanks Salman

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  • InvalidCastException in DataGridView

    - by Max Yaffe
    (Using VS 2010 Beta 2 - .Net 4.0 B2 Rel) I have a class, MyTable, derived from BindingList where S is a struct. S is made up of several other structs, for example: public class MyTable<S>:BindingList<S> where S: struct { ... } public struct MyStruct { public MyReal r1; public MyReal r2; public MyReal R1 {get{...} set{...}} public MyReal R2 {get{...} set{...}} ... } public struct MyReal { private Double d; private void InitFromString(string) {this.d = ...;} public MyReal(Double d) { this.d = d;} public MyReal(string val) { this.d = default(Double); InitFromString(val);} public override string ToString() { return this.real.ToString();} public static explicit operator MyReal(string s) { return new MyReal(s);} public static implicit operator String(MyReal r) { return r.ToString();} ... } OK, I use the MyTable as a binding source for a DataGridView. I can load the data grid easily using InitFromString on individual fields in MyStruct. The problem comes when I try to edit a value in a cell of the DataGridView. Going to the first row, first column, I change the value of the existing number. It gives an exception blizzard, the first line of which says: System.FormatException: Invalid cast from 'System.String' to 'MyReal' I've looked at the casting discussions and reference books but don't see any obvious problems. Any ideas?

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  • AS3 microphone recording/saving works, in-flash PCM playback double speed

    - by Lowgain
    I have a working mic recording script in AS3 which I have been able to successfully use to save .wav files to a server through AMF. These files playback fine in any audio player with no weird effects. For reference, here is what I am doing to capture the mic's ByteArray: (within a class called AudioRecorder) public function startRecording():void { _rawData = new ByteArray(); _microphone.addEventListener(SampleDataEvent.SAMPLE_DATA, _samplesCaptured, false, 0, true); } private function _samplesCaptured(e:SampleDataEvent):void { _rawData.writeBytes(e.data); } This works with no problems. After the recording is complete I can take the _rawData variable and run it through a WavWriter class, etc. However, if I run this same ByteArray as a sound using the following code which I adapted from the adobe cookbook: (within a class called WavPlayer) public function playSound(data:ByteArray):void { _wavData = data; _wavData.position = 0; _sound.addEventListener(SampleDataEvent.SAMPLE_DATA, _playSoundHandler); _channel = _sound.play(); _channel.addEventListener(Event.SOUND_COMPLETE, _onPlaybackComplete, false, 0, true); } private function _playSoundHandler(e:SampleDataEvent):void { if(_wavData.bytesAvailable <= 0) return; for(var i:int = 0; i < 8192; i++) { var sample:Number = 0; if(_wavData.bytesAvailable > 0) sample = _wavData.readFloat(); e.data.writeFloat(sample); } } The audio file plays at double speed! I checked recording bitrates and such and am pretty sure those are all correct, and I tried changing the buffer size and whatever other numbers I could think of. Could it be a mono vs stereo thing? Hope I was clear enough here, thanks!

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  • Asymptotic complexity of a compiler

    - by Meinersbur
    What is the maximal acceptable asymptotic runtime of a general-purpose compiler? For clarification: The complexity of compilation process itself, not of the compiled program. Depending on the program size, for instance, the number of source code characters, statements, variables, procedures, basic blocks, intermediate language instructions, assembler instructions, or whatever. This is highly depending on your point of view, so this is a community wiki. See this from the view of someone who writes a compiler. Will the optimisation level -O4 ever be used for larger programs when one of its optimisations takes O(n^6)? Related questions: When is superoptimisation (exponential complexity or even incomputable) acceptable? What is acceptable for JITs? Does it have to be linear? What is the complexity of established compilers? GCC? VC? Intel? Java? C#? Turbo Pascal? LCC? LLVM? (Reference?) If you do not know what asymptotic complexity is: How long are you willing to wait until the compiler compiled your project? (scripting languages excluded)

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  • MVC View Model Intellisense / Compile error

    - by Marty Trenouth
    I have one Library with my ORM and am working with a MVC Application. I have a problem where the pages won't compile because the Views can't see the Model's properties (which are inherited from lower level base classes). They system throws a compile error saying that 'object' does not contain a definition for 'ID' and no extension method 'ID' accepting a first argument of type 'object' could be found (are you missing a using directive or an assembly reference?) implying that the View is not seeing the model. In the Controller I have full access to the Model and have check the Inherits from portion of the view to validate the correct type is being passed. Controller: return View(new TeraViral_Blog()); View: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<com.models.TeraViral_Blog>" %> <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server"> Index2 </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> <h2>Index2</h2> <fieldset> <legend>Fields</legend> <p> ID: <%= Html.Encode(Model.ID) %> </p> </fieldset> </asp:Content>

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  • Where does Tomcat append / to directory paths?

    - by Anonymouse
    Suppose my Tomcat webapps directory looks like this: webapps/ webapps/fooapp/ webapps/fooapp/WEB-INF/ webapps/fooapp/WEB-INF/web.xml webapps/fooapp/bardir/ When I make a GET request for /fooapp/bardir, Tomcat sees that webapps/fooapp/bardir is a directory and sends back a 302 to /fooapp/bardir/ (with a slash at the end). Here is my question: Where in the Tomcat source code does this take place? (I'm looking at 6.0.x but a correct answer for any version would be a great starting point.) The only reference material I can find on this subject is in the Catalina Functional Specifications which states, regarding the Default Servlet: On each HTTP GET request processed by this servlet, the following processing shall be performed: [...] If the requested resource is a directory: If the request path does not end with "/", redirect to a corresponding path with "/" appended so that relative references in welcome files are resolved correctly. However, this functionality does not appear to be in org.apache.catalina.servlets.DefaultServlet; or at least, it's not there exclusively: if I replace the default servlet in web.xml with a servlet whose servlet-class does not exist, directory paths still come back 302 to add the slash, while every other request comes back with an error as expected.

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  • Calling SubmitChanges on DataContext does not update database.

    - by drasto
    In C# ASP.NET MVC application I use Link to SQL to provide data for my application. I have got simple database schema like this: In my controller class I reference this data context called Model (as you can see on the right side of picture in properties) like this: private Model model = new Model(); I've got a table (List) of Series rendered on my page. It renders properly and I was able to add delete functionality to delete Series like this: public ActionResult Delete(int id) { model.Series.DeleteOnSubmit(model.Series.SingleOrDefault(s => s.ID == id)); model.SubmitChanges(); return RedirectToAction("Index"); } Where appropriate action link looks like this: <%: Html.ActionLink("Delete", "Delete", new { id=item.ID })%> Also create (implemented in similar way) works fine. However edit does not work. My edit looks like this: public ActionResult Edit(int id) { return View(model.Series.SingleOrDefault(s => s.ID == id)); } [HttpPost] public ActionResult Edit(Series series) { if (ModelState.IsValid) { UpdateModel(series); series.Title = series.Title + " some string to ensure title has changed"; model.SubmitChanges(); return RedirectToAction("Index"); } I have controlled that my database has a primary key set up correctly. I debugged my application and found out that everything works as expected until the line with model.SubmitChanges();. This command does not apply the changes of Title property(or any other) against the database. Please help.

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  • Why user control with code behind file doesn't want to compile under MVC2?

    - by kyrisu
    I have user control in my MVC2 app placed in the Content folder (it's not supposed to be a view, just reusable part of the app). UserControl1.ascx looks like: <@ Control AutoEventWireup="true" Language="C#" CodeFile="~/Content/UserControl1.ascx.cs" Inherits="MVCDrill.Content.UserControl1" %> <div runat="server" id="mydiv"> <asp:LinkButton id="lb_text" runat="server"></asp:LinkButton> </div> UserControl1.ascx.cs looks like: using System; using System.Web; using System.Web.UI; namespace MVCDrill.Content { public class UserControl1 : UserControl { public string Text { get { return this.lb_text.Text; } set { this.lb_text.Text = value; } } } } I'm pretty sure this kind of stuff compiled under webforms but I'm getting compilation error: 'MVCDrill.Content.UserControl1' does not contain a definition for 'lb_text' and no extension method 'lb_text' accepting a first argument of type 'MVCDrill.Content.UserControl1' could be found (are you missing a using directive or an assembly reference?) Am I missing something? How to change it (what is the alternative) in MVC2 ? p.s. Intellisense sees lb_text with no problem. I've tried with different controls with the same outcome.

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  • IoC & Interfaces Best Practices

    - by n8wrl
    I'm experimenting with IoC on my way to TDD by fiddling with an existing project. In a nutshell, my question is this: what are the best practices around IoC when public and non-public methods are of interest? There are two classes: public abstract class ThisThingBase { public virtual void Method1() {} public virtual void Method2() {} public ThatThing GetThat() { return new ThatThing(this); } internal virtual void Method3() {} internal virtual void Method4() {} } public class Thathing { public ThatThing(ThisThingBase thing) { m_thing = thing; } ... } ThatThing does some stuff using its ThisThingBase reference to call methods that are often overloaded by descendents of ThisThingBase. Method1 and Method2 are public. Method3 and Method4 are internal and only used by ThatThings. I would like to test ThatThing without ThisThing and vice-versa. Studying up on IoC my first thought was that I should define an IThing interface, implement it by ThisThingBase and pass it to the ThatThing constructor. IThing would be the public interface clients could call but it doesn't include Method3 or Method4 that ThatThing also needs. Should I define a 2nd interface - IThingInternal maybe - for those two methods and pass BOTH interfaces to ThatThing?

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  • sqrt(int_value + 0.0) -- Does it have a purpose?

    - by Earlz
    Hello, while doing some homework in my very strange C++ book, which I've been told before to throw away, had a very peculiar code segment. I know homework stuff always throws in extra "mystery" to try to confuse you like indenting 2 lines after a single-statement for-loop. But this one I'm confused on because it seems to serve some real-purpose. basically it is like this: int counter=10; ... if(pow(floor(sqrt(counter+0.0)),2) == counter) ... I'm interested in this part especially: sqrt(counter+0.0) Is there some purpose to the +0.0? Is this the poormans way of doing a static cast to a double? Does this avoid some compiler warning on some compiler I do not use? The entire program printed the exact same thing and compiled without warnings on g++ whenever I left out the +0.0 part. Maybe I'm not using a weird enough compiler? Edit: Also, does gcc just break standard and not make an error for Ambiguous reference since sqrt can take 3 different types of parameters? [earlz@EarlzBeta-~/projects/homework1] $ cat calc.cpp #include <cmath> int main(){ int counter=0; sqrt(counter); } [earlz@EarlzBeta-~/projects/homework1] $ g++ calc.cpp /usr/lib/libstdc++.so.47.0: warning: strcpy() is almost always misused, please use strlcpy() /usr/lib/libstdc++.so.47.0: warning: strcat() is almost always misused, please use strlcat() [earlz@EarlzBeta-~/projects/homework1] $

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  • Sharepoint: Integrity of lookup fields after a list import

    - by driAn
    Hi there I got a question about the behavior of lookup fields when importing data. I wonder how the lookup fields behave when the list they point to is being replaced/imported. To explain the issue, I will provide a quick example below: As example, assume we have these two sharepoint lists: Product Types ------------- + Type Name + Code Nr + etc Products -------- + Product Name + Product Type (Lookup field to list "Product Types") + etc In my scenario, the Products List contains production data on the production Sharepoint platform. It is filled with data by the business users. However the Product Types list contains rather static data and is maintained by the developer. Now after a development cycle, the developer wants to deploy his new webparts and his new data (product types list). The developer performs the following procedure: On the dev machine: Export "product type" list using stsadm On the production machine: Delete all items in the "product type" list On the production machine: Import the "product type" list using stsadm This means we basically replace the "product type" list on the production server while keeping the "product" list as it is. Now the question: Is this safe? Will the lookup references break under certain circumstances? Any downside of this import/export procedure? What happens if someone accesses a "product" during the import? Will the (now invalid) reference clear its own content (become a null value). What happens if the schema of the "product type" list changes (new column)? Will this cause any troubles? Thanks for all feedback and suggestions!

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  • Java: volatile guarantees and out-of-order execution

    - by WizardOfOdds
    Note that this question is solely about the volatile keyword and the volatile guarantees: it is not about the synchronized keyword (so please don't answer "you must use synchronize" for I don't have any issue to solve: I simply want to understand the volatile guarantees (or lack of guarantees) regarding out-of-order execution). Say we have an object containing two volatile String references that are initialized to null by the constructor and that we have only one way to modify the two String: by calling setBoth(...) and that we can only set their references afterwards to non-null reference (only the constructor is allowed to set them to null). For example (it's just an example, there's no question yet): public class SO { private volatile String a; private volatile String b; public SO() { a = null; b = null; } public void setBoth( @NotNull final String one, @NotNull final String two ) { a = one; b = two; } public String getA() { return a; } public String getB() { return b; } } In setBoth(...), the line assigning the non-null parameter "a" appears before the line assigning the non-null parameter "b". Then if I do this (once again, there's no question, the question is coming next): if ( so.getB() != null ) { System.out.println( so.getA().length ); } Am I correct in my understanding that due to out-of-order execution I can get a NullPointerException? In other words: there's no guarantee that because I read a non-null "b" I'll read a non-null "a"? Because due to out-of-order (multi)processor and the way volatile works "b" could be assigned before "a"? volatile guarantees that reads subsequent to a write shall always see the last written value, but here there's an out-of-order "issue" right? (once again, the "issue" is made on purpose to try to understand the semantics of the volatile keyword and the Java Memory Model, not to solve a problem).

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  • Android Custom Dialog NullPointerException

    - by Kyle Hughes
    I cannot for the life of me figure out why I'm getting a NullPointerException. When a user clicks on a particular image, a dialog window is supposed to pop-up and display a larger version of said image: private OnClickListener coverListener = new OnClickListener() { public void onClick(View v) { showDialog(DIALOG_COVER); } }; DIALOG_COVER is set to = 0. The associated onCreateDialog looks like this: protected Dialog onCreateDialog(int id) { Dialog dialog; switch(id) { case DIALOG_COVER: dialog = new Dialog(mContext); dialog.setContentView(R.layout.cover_dialog); dialog.setTitle(book.getTitle()); ImageView coverLarge = (ImageView)findViewById(R.id.coverLarge); coverLarge.setImageBitmap(book.getCover()); break; default: dialog = null; } return dialog; } For reference, this is cover_dialog.xml: <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/coverDialog" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding="10dp"> <ImageView android:id="@+id/coverLarge" android:layout_width="wrap_content" android:layout_height="wrap_content" android:scaleType="fitStart" /></LinearLayout> Now, when the image previously described is clicked, the application immediately crashes and throws the following error through LogCat: 06-08 13:29:17.727: ERROR/AndroidRuntime(2220): Uncaught handler: thread main exiting due to uncaught exception 06-08 13:29:17.757: ERROR/AndroidRuntime(2220): java.lang.NullPointerException 06-08 13:29:17.757: ERROR/AndroidRuntime(2220): at org.kylehughes.android.brarian.AndroidBrarian.onCreateDialog(AndroidBrarian.java:259) The line in question refers to this line inside of onCreateDialog: coverLarge.setImageBitmap(book.getCover()); Basically, I don't get why coverLarge is null at that point. Any help would be much appreciated.

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  • XNA 2D mouse picking

    - by Corndog
    I'm working on a simple 2D Real time strategy game using XNA. Right now I have reached the point where I need to be able to click on the sprite for a unit or building and be able to reference the object associated with that sprite. From the research I have done over the last three days I have found many references on how to do "Mouse picking" in 3D which does not seem to apply to my situation. I understand that another way to do this is to simply have an array of all "selectable" objects in the world and when the player clicks on a sprite it checks the mouse location against the locations of all the objects in the array. the problem I have with this approach is that it would become rather slow if the number of units and buildings grows to larger numbers. (it also does not seem very elegant) so what are some other ways I could do this. (Please note that I have also worked over the ideas of using a Hash table to associate the object with the sprite location, and using a 2 dimensional array where each location in the array represents one pixel in the world. once again they seem like rather clunky ways of doing things.)

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  • DataGridComboBoxColumn was not found

    - by Budda
    The System.Windows.Controls.Data.DataGrid is used in my Silverlight application, but on attempt to add 'DataGridComboBoxColumn' column to the grid the following error messages are obtained: Error 1 The tag 'DataGridComboBoxColumn' does not exist in XML namespace 'clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data'. C:\Project\Budda\VFMElita\VfmElitaView\Pages\SquadView.xaml 140 22 VfmElitaView Error 2 The type 'data:DataGridComboBoxColumn' was not found. Verify that you are not missing an assembly reference and that all referenced assemblies have been built. C:\Project\Budda\VFMElita\VfmElitaView\Pages\SquadView.xaml 142 22 VfmElitaView Here is my "header" of the xaml-file: Here is grid: <StackPanel Grid.Row="1" Grid.Column="0" Grid.RowSpan="2"> <TextBlock Text="????"/> <data:DataGrid AutoGenerateColumns="False" ItemsSource="{Binding FieldPlayers}"> <data:DataGrid.Columns> <!--<data:DataGridTemplateColumn Header="#"> <data:DataGridTemplateColumn.CellTemplate> <DataTemplate> <TextBlock Margin="4" Loaded="TextBlock_Loaded"/> </DataTemplate> </data:DataGridTemplateColumn.CellTemplate> </data:DataGridTemplateColumn>--> <data:DataGridTextColumn Header="?" Binding="{Binding Number}"/> <data:DataGridComboBoxColumn> - that doesn't work </data:DataGridComboBoxColumn> </data:DataGrid.Columns> </data:DataGrid> </StackPanel> What is required to get 'DataGridComboBoxColumn' workable? Any help is welcome. Thanks.

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  • Validating Application Settings Key Values in Isolated Storage for Windows Phone Applications

    - by Martin Anderson
    Hello everyone. I am very new at all this c# Windows Phone programming, so this is most probably a dumb question, but I need to know anywho... IsolatedStorageSettings appSettings = IsolatedStorageSettings.ApplicationSettings; if (!appSettings.Contains("isFirstRun")) { firstrunCheckBox.Opacity = 0.5; MessageBox.Show("isFirstRun not found - creating as true"); appSettings.Add("isFirstRun", "true"); appSettings.Save(); firstrunCheckBox.Opacity = 1; firstrunCheckBox.IsChecked = true; } else { if (appSettings["isFirstRun"] == "true") { firstrunCheckBox.Opacity = 1; firstrunCheckBox.IsChecked = true; } else if (appSettings["isFirstRun"] == "false") { firstrunCheckBox.Opacity = 1; firstrunCheckBox.IsChecked = false; } else { firstrunCheckBox.Opacity = 0.5; } } I am trying to firstly check if there is a specific key in my Application Settings Isolated Storage, and then wish to make a CheckBox appear checked or unchecked depending on if the value for that key is "true" or "false". Also I am defaulting the opacity of the checkbox to 0.5 opacity when no action is taken upon it. With the code I have, I get the warnings Possible unintended reference comparison; to get a value comparison, cast the left hand side to type 'string' Can someone tell me what I am doing wrong. I have explored storing data in an Isolated Storage txt file, and that worked, I am now trying Application Settings, and will finally try to download and store an xml file, as well as create and store user settings into an xml file. I want to try understand all the options open to me, and use which ever runs better and quicker

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  • Question about mixing MEF and Unity

    - by Dave
    I'm finally diving into Unity head first, and have run into my first real problem. I've been gradually changing some things in my app from being MEF-resolved to Unity-resolved. Everything went fine on the application side, but then I realized that my plugins were not being loaded. I started to look into this issue, and I believe it's a case where MEF and Unity don't mix. Plugins are loaded by MEF, but each plugin needs to get access to the shared libraries in my application, like app preferences, logging, etc. Initially, my plugin constructor had the ImportingConstructor attribute. I then replaced it with InjectionConstructor so that Unity could resolve its shared library dependencies. But because I did that, MEF no longer loaded it! Then I used both attributes, which compiled, but then I got a composition error (MEF). I figured that this was because the constructor takes a parameter that was once resolved by a MEF Import, so I removed all parameters. As expected, now MEF was able to load my plugin, but because the constructor needs to call into the interface that was once passed in, construction fails. So now I'm at a point where I can get MEF to start to load my plugin, but can't do anything with it because the plugin relies on shared libraries that are registered with Unity. For those of you that have successfully mixed MEF and Unity, how do you go about resolving the references to the shared libraries with Unity? It seems like a catch-22, where in order to have Unity work with the plugin, I'd have to create the plugin via Resolve, but then it's impossible to use MEF. UPDATE I can work around this problem by using an ImportingConstructor for the plugin that takes an IUnityContainer, and then call Resolve for each interface that I need, but although it works, it is incredibly lame to do it this way, as this would require all plugin authors to remember to save a reference to the passed in IUnityContainer...

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  • When actually is a closure created?

    - by Jian Lin
    Is it true that a closure is created in the following cases for foo, but not for bar? Case 1: <script type="text/javascript"> function foo() { } </script> foo is a closure with a scope chain with only the global scope. Case 2: <script type="text/javascript"> var i = 1; function foo() { return i; } </script> same as Case 1. Case 3: <script type="text/javascript"> function Circle(r) { this.r = r; } Circle.prototype.foo = function() { return 3.1415 * this.r * this.r } </script> in this case, Circle.prototype.foo (which returns the circle's area) refers to a closure with only the global scope. (this closure is created). Case 4: <script type="text/javascript"> function foo() { function bar() { } } </script> here, foo is a closure with only the global scope, but bar is not a closure (yet), because the function foo is not invoked in the code, so no closure goo is ever created. It will only exist if foo is invoked , and the closure bar will exist until foo returns, and the closure bar will then be garbage collected, since there is no reference to it at all anywhere. So when the function doesn't exist, can't be invoked, can't be referenced, then the closure doesn't exist yet (never created yet). Only when the function can be invoked or can be referenced, then the closure is actually created?

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  • ASP.Net ListView and event handling.

    - by Neil
    I have an .ascx which contains a listview. Let's call it the parent. Within its ItemTemplate I reference a second .ascx which is basically another listview, let's call it the child. On the parent, the child control is wrapped in a placeholder tag. I use this place holder tag to show and hide the child. Psuedo code: The child listview has a 'close' button in its Layout Template. Let's call it "btnClose" with an onClick event of "btnClose_Click". I want to use this button to set the visibility of the containing placeholder. I'm trying to avoid doing something like using PlaceHolder plhChild = (PlaceHolder)childListCtl.NamingContainer since I can't guarantee every instance of the child .ascx will be contained within a placeholder. I tried creating an event in the child that could be subscribed to. Psuedo code: public delegate CloseButtonHandler(); public event CloseButtonHandler CloseButtonEvent; And in the actual btnClose_Click(Object sender, EventArgs e) event I have: if (CloseButtonEvent != null) CloseButtonEvent(); My problem is that the delegate CloseButtonEvent is always null. I've tried assigning the delegate in the listview's OnDatabound event of the parent and on the click event, to set the plhChild.visible = true, and I've stepped through the code and know the delegate instantiation works in both place, but again, when it gets to the btnClose_Click event on the child, the delegate is null. Any help would be appreciated. Neil

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  • What is Adobe Flex? Is it just Flash II?

    - by Adam Davis
    Question Alright, I'm confused by all the buzzwords and press release bingo going on. What is the relationship between flash and flex: Replace flash (not really compatible) Enhance flash The next version of flash but still basically compatible Separate technology altogether ??? If I'm starting out in Flash now, should I just skip to Flex? Follow up Ok, so what I'm hearing is that there's three different parts to the puzzle: Flash The graphical editor used to make "Flash Movies", ie it's an IDE that focuses on the visual aspect of "Flash" (Officially Flash CS3?) The official name for the display plugins (ie, "Download Flash Now!") A general reference to the entire technology stack In terms of the editor, it's a linear timeline based editor, best used for animations with complex interactivity. Actionscript The "Flash" programming language Flex An Adobe Flash IDE that focuses on the coding/programming aspect of "Flash" (Flex Builder?) A Flash library that enhances Flash and makes it easier to program for (Flex SDK?) Is not bound to a timeline (as the Flash IDE is) and so "standard" applications are more easily accomplished. Is this correct?

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  • PJSIP Custom Registration Header (iOS)

    - by Daniel Redington
    I am attempting to setup SIP communication with an internal server (using the PJSIP library), however, this server requires a custom header field with a specified header value for the REGISTRATION call. For example's sake we'll call this required header "MyHeader". From what I've found, the pjsua_acc_add() function will add an account and register it to the server using a config struct. The parameter "reg_hdr_list" of the config struct has the description "The optional custom SIP headers to be put in the registration request." Which sounds like exactly what I need, however doesn't seem to have any effect on the call itself. Here's what I have so far: pjsua_acc_config cfg; pjsua_acc_config_default(&cfg); //...Some other config stuff related to the server... pjsip_hdr test; test.name = pj_str("MyHeader"); test.sname = pj_str("MyHdr"); test.type = PJSIP_H_OTHER; test.prev = cfg.reg_hdr_list.prev; test.next = cfg.reg_hdr_list.next; cfg.reg_hdr_list = test; pj_status_t status; status = pjsua_acc_add(&cfg, PJ_TRUE, &acc_id); From the server side, there are no extra header fields or anything. And the struct that is used to define the header (pjsua_hdr) has no "value" or equivalent field, so even if it did create the header, how does it set the value? Here's the refrence for the header list definition: Link And the reference for the header struct: Link Any help would be greatly appreciated!

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  • Practical size limitations for RDBMS

    - by grenade
    I am working on a project that must store very large datasets and associated reference data. I have never come across a project that required tables quite this large. I have proved that at least one development environment cannot cope at the database tier with the processing required by the complex queries against views that the application layer generates (views with multiple inner and outer joins, grouping, summing and averaging against tables with 90 million rows). The RDBMS that I have tested against is DB2 on AIX. The dev environment that failed was loaded with 1/20th of the volume that will be processed in production. I am assured that the production hardware is superior to the dev and staging hardware but I just don't believe that it will cope with the sheer volume of data and complexity of queries. Before the dev environment failed, it was taking in excess of 5 minutes to return a small dataset (several hundred rows) that was produced by a complex query (many joins, lots of grouping, summing and averaging) against the large tables. My gut feeling is that the db architecture must change so that the aggregations currently provided by the views are performed as part of an off-peak batch process. Now for my question. I am assured by people who claim to have experience of this sort of thing (which I do not) that my fears are unfounded. Are they? Can a modern RDBMS (SQL Server 2008, Oracle, DB2) cope with the volume and complexity I have described (given an appropriate amount of hardware) or are we in the realm of technologies like Google's BigTable? I'm hoping for answers from folks who have actually had to work with this sort of volume at a non-theoretical level.

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  • Daylight Savings Handling in DateDiff() in MS Access?

    - by PowerUser
    I am fully aware of DateDiff()'s inability to handle daylight savings issues. Since I often use it to compare the number of hours or days between 2 datetimes several months apart, I need to write up a solution to handle DST. This is what I came up with, a function that first subtracts 60 minutes from a datetime value if it falls within the date ranges specified in a local table (LU_DST). Thus, the usage would be: datediff("n",Conv_DST_to_Local([date1]),Conv_DST_to_Local([date2])) My question is: Is there a better way to handle this? I'm going to make a wild guess that I'm not the first person with this question. This seems like the kind of thing that should have been added to one of the core reference libraries. Is there a way for me to access my system clock to ask it if DST was in effect at a certain date & time? Function Conv_DST_to_Local(X As Date) As Date Dim rst As DAO.Recordset Set rst = CurrentDb.OpenRecordset("LU_DST") Conv_DST_to_Local = X While rst.EOF = False If X > rst.Fields(0) And X < rst.Fields(1) Then Conv_DST_to_Local = DateAdd("n", -60, X) rst.MoveNext Wend End Function Notes I have visited and imported the BAS file of http://www.cpearson.com/excel/TimeZoneAndDaylightTime.aspx. I spent at least an hour by now reading through it and, while it may do its job well, I can't figure out how to modify it to my needs. But if you have an answer using his data structures, I'll take a look. Timezones are not an issue since this is all local time.

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  • passing hashes to a subroutine

    - by Vishalrix
    In one of my main( or primary) routines,I have two or more hashes. I want the subroutine foo() to recieve these possibly-multiple hashes as distinct hashes. Right now I have no preference if they go by value, or as references. I am struggling with this for the last many hours and would appreciate help, so that I dont have to leave perl for php! ( I am using mod_perl, or will be) Right now I have got some answer to my requirement, shown here From http://forums.gentoo.org/viewtopic-t-803720-start-0.html # sub: dump the hash values with the keys '1' and '3' sub dumpvals { foreach $h (@_) { print "1: $h->{1} 3: $h->{3}\n"; } } # initialize an array of anonymous hash references @arr = ({1,2,3,4}, {1,7,3,8}); # create a new hash and add the reference to the array $t{1} = 5; $t{3} = 6; push @arr, \%t; # call the sub dumpvals(@arr); I only want to extend it so that in dumpvals I could do something like this: foreach my %k ( keys @_[0]) { # use $k and @_[0], and others } The syntax is wrong, but I suppose you can tell that I am trying to get the keys of the first hash ( hash1 or h1), and iterate over them. How to do it in the latter code snippet above?

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