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• [C#] Onpaint events (invalidated) changing execution order after a period normal operation (runtime)

  - by Luke Mcneice

  Hi all, I have 3 data graphs that are painted via the their paint events. When I have data that I need to insert into the graph I call the controls invalidate() command. The first control's paint event actually creates a bitmap buffer for the other 2 graphs to avoid repeating a long loop. So the invalidate commands are in a specific order (1,2,3). This works well, however when the graphed data reaches the end of the graph window (PictureBox) where the data would normally start scrolling, the paint events begin firing in the wrong order (2,3,1). has anyone came across this before? why might this be happening?

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• When binding a client TCP socket to a specific local port with Winsock, SO_REUSEADDR does not have a

  - by Checkers

  I'm binding a client TCP socket to a specific local port. To handle the situation where the socket remains in TIME_WAIT state for some time, I use setsockopt() with SO_REUSEADDR on a socket. It works on Linux, but does not work on Windows, I get WSAEADDRINUSE on connect() call when the previous connection is still in TIME_WAIT. MSDN is not exactly clear what should happen with client sockets: [...] For server applications that need to bind multiple sockets to the same port number, consider using setsockopt (SO_REUSEADDR). Client applications usually need not call bind at all—connect chooses an unused port automatically. [...] How do I avoid this?

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• WCF: limit number of calls per hour - per user

  - by Eric Eijkelenboom

  Hi guys, I've got a WCF service (basicHttpBinding, basic authentication, IIS 6.0) on which I want to restrict the number of calls per hour - on user basis. For example, max 1000 calls per user, per hour (a la Google Maps, etc). I also want to implement some sort of subscription mechanism, so that users can upgrade their call-limit across various 'price plans'. I know that I could achieve this with a custom Inspector, backed by a DB containing some sort of 'subscription' table and a counter, but I'd like to avoid reinventing the wheel. Does anyone have experience doing this? Are there 3rd party projects/libraries that support this out of the box? Thanks. Eric

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• Django : proper way to use model, duplicates!

  - by llazzaro

  Hello, I have a question about the proper, best way to manage the model. I am relative newbie to django, so I think I need to read more docs, tutorials,etc (suggestions for this would be cool!). Anyway, this is my question : I have a python web crawler, that is "connected" with django model. Crawling is done once a day, so its really common to find "duplicates". To avoid duplicates I do this : cars = Car.Objects.filter(name=crawledItem['name']) if len(cars) 0: #object already exists, update it car = cars[0] else: car = Car() #some non-relevant code here car.save() I want to know, if this is the proper/correct way to do it or its any "automatic" way to do it. Its possible to put the logic inside the Car() constructor also, should I do that? Thanks a lot!

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• Encrypting Files with AES, Encrypting Key with RSA - Am I on the right track?

  - by Shawn Steward

  Overview: I'm trying to design an application that will encrypt files to safely send through the mail. I'm planning on using AES/RijndaelManaged encryption from .Net to encrypt the files initially, using a randomly generated key using RNGCryptoServiceProvider. I'm then encrypting this random AES key with a RSA Public key. The receiver of the data is the only one with the RSA Private key to decrypt it. My question: Is this the proper way to do something like this? If so, is it safe to send this RSA-Encrypted key with the data since it requires the private key to decrypt? Also - when having the end user generate their Public/Private key pair, what is the best way to save the Private key? I do not want it to be only accessible from one machine, so I am trying to avoid using the user's key store. But MSDN says it is not safe to save the key to a file, so how else can you accomplish this?

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• Sharepoint Foundation 2010 installation problems

  - by Robert Koritnik

  I'm having problems installing development machine for Sharepoint (Foundation) 2010. This is what I did so far on the same machine: Installed a clean Windows 7 x64 with 4GB of RAM without being part of any domain. Just a simple standalone machine. Enabled IIS related features as described here except IIS6 related ones (two of them) Installed SQL Server 2008 R2 Development Edition (DB Engine and Writer being enabled but not SQL Agent) Installed Visual Studio 2010 Premium Started installing Sharepoint Foundation 2010 with first extracting files, changing config to enable Windows 7 installation and then installed it as Server Farm (then Complete) to avoid installing SQL Express. Created a separate SPF_CONFIG local user with Logon on as a service right. Opened SPF Management Shell and run New-SPConfigurationDatabase so I am able to use a non-domain username (SPF_CONFIG that I created in the previous step) But all I get is this: The outcome after this error is: Database Sharepoint2010Config is created User SPF_CONFIG is added to SQL Server and attached to this newly created database as dbowner and checking SQL server security logins this user has following rights: dbcreator securityadmin public

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• Will Apple's new "originally written in" clause affect your decision to target the iPhone?

  - by Michael Aaron Safyan

  So, you've probably heard about Apple's change to its agreement to prohibit source-to-source translation, thereby blocking translation from Flash (in CS5) and also from Android (via XMLVM). You may also have read about a response by a well-known Adobe developer, and calls to boycott development for the iPhone. Given that this audience is a better representative of the developer community than those who post comments on the NYT, Digg, and other news sites, I was wondering what your opinions were about this decision. Will any of you switch to Android from the iPhone or avoid development on the iPhone as a result of this? Since this is fairly subjective, I am making this a community wiki. Also, please, keep things civil.

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• Why does 'uses unit' disappear when I had a new unit ?

  - by TridenT

  I have a Unit test project for my Application using DUnit framework. This project have a unit surrounded by a $IFDEF to output test-results in a xml file instead of the gui or just command line. XML_OUTPUT define is enabled by switching the Build configuration. program DelphiCodeToDoc_Tests; uses TestFramework, TextTestRunner, Sysutils, Forms, GUITestRunner, {$IFDEF XML_OUTPUT} XmlTestRunner2 in 'DUnit_addon\XmlTestRunner2.pas', {$ENDIF} DCTDSetupTests in 'IntegrationTests\DCTDSetupTests.pas', ... This works perfectly. The issue starts when I'm adding a new unit to this project from the IDE (a new unit with 'FileNewUnit'). The Test project is now : uses TestFramework, TextTestRunner, Sysutils, Forms, GUITestRunner, DCTDSetupTests in 'IntegrationTests\DCTDSetupTests.pas', ... MyNewUnit in 'IntegrationTests\MyNewUnit.pas'; As you see, the test XML_OUTPUT has disappeared ... Each time I'm adding a unit, Delphi IDE deletes this test. Do you know why and how I can avoid it ?

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• Dealing with Unity's Global Menu and Overlay Scrollbars under Free Pascal/Lazarus

  - by Gustavo Carreno

  I've had some problems under the IDE that were fixed with unsettings and disabling Global menu and the Overlay Scrollbars. I've reported the problem in Lazarus' Mantis: #0021465, #0021467. There is also this bug report talking a bit more about it: #0019266 Their solution was to use unsettings to turn off Global Menu and Overlay Scrollbars. I've had a quick search about the problem and there's an open bug report at Launchpad: overlay scrolling is broken in lazarus. So, is the problem related to "lib overlay scrollbar"? If it is, is there a solution via code, to avoid turning off both the Global Menu and Overlay Scrollbars? If NOT, is there anyone taking notice and fixing the issue? Many thanks, Gus

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• Is there a faster alternative to using textures in XNA?

  - by Matthew Bowen

  I am writing a map editing program for a 2D game using XNA. To create a Texture2D for all of the tiles that a map requires takes too long. Are there any alternatives to using textures for drawing with XNA? I attempted to create just one texture per tile set instead of a texture for every tile in a tile set, but there is a limit to the size of textures and I could not fit all the tiles of a tile set into one texture. Currently the program contains all the would-be textures in memory as Bitmap objects. Is there a way to simply draw a Bitmap object to the screen in XNA? I have searched but I cannot find any information on this. This approach would avoid having to create textures altogether, however any tinting or effects I would have to do to the bitmap directly. Any help would be very much appreciated. Thanks

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• ALTER TABLE without locking the table?

  - by Daniel

  When doing an ALTER TABLE statement in MySQL, the whole table is read-locked for the duration of the statement. If it's a big table, that means insert or update statements could be locked for a looooong time. Is there a way to do a "hot alter", like adding a column in such a way that the table is still updatable throughout the process? Mostly I'm interested in a solution for MySQL but I'd be interested in other RDBMS if MySQL can't do it. To clarify, my purpose is simply to avoid downtime when a new feature that requires an extra table column is pushed to production. Any database schema will change over time, that's just a fact of life. I don't see why we should accept that these changes must inevitably result in downtime; that's just weak.

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• Problem with Qt::QueuedConnection, signal delivered after disconnect

  - by lutku

  Hi, I just discovered interesting behavior of queued connection in Qt 4.6: First queued connection is made: connect(someSender, SIGNAL(completed()), this, SLOT(handleCompletion()), Qt::QueuedConnection) Then someSender sends the signal: emit completed() Before receiving signal (as it is in queue), I disconnect from the signal: disconnect(someSender, SIGNAL(completed()), this, SLOT(handleCompletion()) Still, handleCompletion slot is invoked at next eventloop iteration. I can prevent this from happening by using someSender-blockSignals(true) at correct point, but it feels awful not to mention having some boolean flag to disable slot's functionality. Especially, I feel amazed that this behavior is not mentioned in Qt documentation (at least I haven't found). Finally the question: any sensible way to avoid this from happening?

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• Ninject: Dynamically loading modules in Silverlight

  - by joblot

  The reason I want to load modules dynamically is to avoid circular dependency issue. I have following layers View -- ViewModel -- DataProvider -- ServiceClient (wcf proxies). Now I want a static IoC container that can be shared across these layers. I want to make my View testable and to do that I’ll have to inject the various dependencies in various layers and mock out those dependencies as well. Now issue I am facing is where to declare and load ninject modules. i also realised in Silverlight version of Ninject there is no version of Load which take string arugment, which can be used to load the modules dynamically Load("*.dll"). How can I achieve dynamic loading in Silverlight Thanks

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• Optimization of running total calculation in SQL for multiple values per join condition

  - by Kiril

  I have the following table (test_table): date value --------------- d1 10.0 d1 20.0 d2 60.0 d2 10.0 d2 -20.0 d3 40.0 I calculate the running total as follows. I use the same query twice, because first I need to calculate the values for a specifi date, and afterwards I can calculate the running total. Otherwise, joining the two tables where date is not unique, I would get too many results from the join: SELECT t1.date, SUM(t2.value) AS total FROM (SELECT date, SUM(value) AS value FROM test_table GROUP BY date) AS t1 JOIN (SELECT date, SUM(value) AS value FROM test_table GROUP BY date) AS t2 ON t1.date >= t2.date GROUP BY t1.date ORDER BY t1.date This gives me (which is fine): date total ------------- d1 30.0 d2 80.0 d3 120.0 BUT, this query isn't very efficient, because I need to change conditions in two places, if necessary. In production, the test_table is a lot bigger ( 4 Mio. rows), and the query takes too much time to complete. Question: How can I avoid using the same query twice?

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• Cocoa-Binding : Submit changes manually?

  - by Holli

  Hello in my application I have a NSTableView bound to an ArrayController (arrangedObjects). I also have a Details-View (just some textfields) bound to the same Controller (selection). Now every time I edit a textfield the changes are automatically send to the ArrayController and the Table changes as well. How can I avoid this? What I want is a "Submit-Button". Changes on the data should only be send to the controller when I press the button and not automatically every time I do an edit.

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• Best way to show code snippets in word?

  - by Larry

  Does anyone know a good way to display code in Microsoft Word documents? I have tried to include code as regular text which looks awful and gets in the way when editing regular text. I have also tried inserting objects, a WordPad document and Text Box, into the document then putting the code inside those objects. The code looks much better and is easier to avoid while editing the rest of the text. However, these objects can only span one page which makes editing a nightmare when several pages of code need to be added. Lastly, I know that there are much better editors/formats that have no problem handling this but I am stuck working with MS word.

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• Exception thrown while working with JTabbedPane

  - by Halo

  I'm using a JTabbedPane in my application and I listen to its changes with ChangeListener so that I can know which tab is currently selected. So my stateChanged method is; public void stateChanged(ChangeEvent e) { currentPageIndex = jTabbedPane.getSelectedIndex(); } But while I'm adding new tabs to the JTabbedPane it throws an ArrayIndexOutOfBoundsException in the method above, I don't know why. Some suggested for a similar case that this is a bug http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4873983, but as you'll see some says the solution is to work with Swing from EventDispatchThread. What does it mean, do they mean the SwingUtilities.invokeLater thing? Can someone show me how I can modify my stateChanged method accordingly to avoid the exception?

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• Is there a way to declare a variable that implements multiple interfaces in .Net?

  - by Bryan Anderson

  Similar to this Java question. I would like to specify that a variable implements multiple interfaces. For instance private {IFirstInterface, ISecondInterface} _foo; public void SetFoo({IFirstInterface, ISecondInterface} value) { _foo = value; } Requirements: I don't have the ability to add an interface to most type that would be passed in to Foo. So I can't create a third interface that inherits from IFirstInterface and ISecondInterface. I would like to avoid making the containing class generic if possible because the type of Foo doesn't have much to do with the class and the user isn't likely to know it at compile time. I need to use foo to access methods in both interfaces at a later time. I would like to do this in a compiler safe way, i.e. no trying to cast to the interface just before trying to use it. If foo does not implement both interfaces quite a bit of functionality won't work properly. Is this possible?

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• Changing system colors for a single application (Windows, .NET)

  - by Michal Czardybon

  I know I should generally avoid messing up with such system settings, but my application do already use nonstandard colors and I have no influence on that. I would like to be able to add standard .NET controls in some places, but their colors do not match. I would like to have a hack that would replace system colors for this one application. One more important thing to note is that it is a .NET application. My (incomplete) ideas so far were: To create a proxy User32.dll library with replaced GetSysColor, but it would be very tedious (731 functions to be redirected, 1 to be replaced) and I do not know how to force my application to use that particular copy. To intercept somehow invocations to GetSysColors (unfortunatelly it is somewhere in the CLR I think). To modify somehow .NET class SystemColors (in memory? is it possible?). Do you have any idea, what is the best (and complete) way to achieve this?

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• Server side includes on app engine (<!-- include virtual="header.html" -->)?

  - by Alexandre H. Tremblay

  Hi, I have been trying to figure this out a while. I would like to make my app engine website use basic html and shtml whenever in order to avoid the slow warm-up phase of jsp apps on app engine. This is so that my landing pages load instantly. Basically, I am trying to include an html file into my main html file (index.html - I tried index.shtml). This is the command I try: <!-- include virtual="header.html" --> However it does not work. The server side includes to not seem to get executed in app engine. Do I need to enable these commands somewhere first - or does app engine simply not allow them?

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• Temp file that exists only in RAM?

  - by Auraomega

  I'm trying to write an encrpytion using the OTP method. In keeping with the security theories I need the plain text documents to be stored only in memory and never ever written to a physical drive. The tmpnam command appears to be what I need, but from what I can see it saves the file on the disk and not the RAM. Using C++ is there any (platform independent) method that allows a file to exist only in RAM? I would like to avoid using a RAM disk method if possible. Thanks Edit: Thanks, its more just a learning thing for me, I'm new to encryption and just working through different methods, I don't actually plan on using many of them (esspecially OTP due to doubling the original file size because of the "pad"). If I'm totally honest, I'm a Linux user so ditching Windows wouldn't be too bad, I'm looking into using RAM disks for now as FUSE seems a bit overkill for a "learning" thing.

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• XSLT: Disable output escaping in an entire document.

  - by Kragen

  I'm trying to generate some C# code using xslt - its working great until I get to generics and need to output some text like this: MyClass<Type> In this case I've found that the only way to emit this is to do the following: MyClass<xsl:text disable-output-escaping="yes">&lt;</xsl:text>Type<xsl:text disable-output-escaping="yes">&gt;</xsl:text> Where: Often it all needs to go on one line, otherwise you end up with line breaks in the generated code In the above example I technically could have used only 1 <xsl:text />, however usually the type Type is given by some other template, e.g: <xsl:value-of select="@type" /> I don't mind having to write &lt; a lot, but I would like to avoid writing <xsl:text disable-output-escaping="yes">&lt;</xsl:text> for just a single character! Is there any way of doing disable-output-escaping="yes" for the entire document?

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• Not-quite-JSON string deserialization in Python

  - by cpharmston

  I get the following text as a string from an XML-based REST API 'd':4 'ca':5 'sen':1 'diann':2,6,8 'feinstein':3,7,9 that I'm looking to deserialize into a pretty little Python dictionary: { 'd': [4], 'ca': [5], 'sen': [1], 'diann': [2, 6, 8], 'feinstein': [3, 7, 9] } I'm hoping to avoid using regular expressions or heavy string manipulation, as this format isn't documented and may change. The best I've been able to come up with: members = {} for m in elem.text.split(' '): m = m.split(':') members[m[0].replace("'", '')] = map(int, m[1].split(',')) return members Obviously a terrible approach, but it works, and that's better than anything else I've got right now. Any suggestions on better approaches?

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• Is there a way to load a different cacerts than the one specified in the java_home/jre/lib/security

  - by feniix

  I have a single installation of java in a system that runs 2 or 3 applications. All the applications use the same runtime. Is there a way to specify a different keystores for the ca certs than the one in java_home/jre/lib/security. That is, is there an option to specify an "extra" keystore that is loaded and added to the certs loaded from java_home/jre/lib/security/cacerts? What I want to avoid is having to re-import our local ca every time I upgrade the jdk in the box.

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• How can I pass checkbox onclick event to parent onclick ?

  - by Kim

  I a with an onclick event and , and inside it. When I click on the checkbox then the div-onclick event doesnt fire - I would like it to fire without having to dublicate the onclick onto the checkbox. <div id="id-tag" onclick="do()"> <span>text</span> <img src="pic.jpg" /> <input type="checkbox" name="mycheck" /> </div> I know the div-idtag but ideally would like to avoid specifying it inside the checkbox. Using another function call on the checkbox onclick to call the parent is NOT what I am looking for, like onclick="run_parent_onclick()" but this is okay (untested) onclick="this.parent.click()"

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