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  • jQuery: Find the text of a list item that contains a nested ul

    - by ScottE
    I have the following: <ul id="list"> <li>item1 <ul> <li>sub1</li> <li>sub2</li> </ul> </li> </ul> I'd like to respond to a li click event and use the text of the li elsewhere. However, if the click is on an li that contains a nested ul, I of course get the text of all elements. $("#list li").click(function() { alert($(this).text()); }); returns item1sub1sub2, as expected. I can't figure out how to get just 'item1' if the item 1 li is clicked. I tried the following (among other things) with no luck: $("#list li").click(function() { alert($(this).filter("ul").text()); }); Any ideas? EDIT This is a snippet of an example - it could be multiple levels deep. I also do not want to wrap the list item text in a span or other markup.

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  • How to reliably get size of C-style array?

    - by Frank
    How do I reliably get the size of a C-style array? The method often recommended seems to be to use sizeof, but it doesn't work in the foo function, where x is passed in: #include <iostream> void foo(int x[]) { std::cerr << (sizeof(x) / sizeof(int)); // 2 } int main(){ int x[] = {1,2,3,4,5}; std::cerr << (sizeof(x) / sizeof(int)); // 5 foo(x); return 0; } Answers to this question recommend sizeof but they don't say that it (apparently?) doesn't work if you pass the array around. So, do I have to use a sentinel instead? (I don't think the users of my foo function can always be trusted to put a sentinel at the end. Of course, I could use std::vector, but then I don't get the nice shorthand syntax {1,2,3,4,5}.)

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  • Images not shown when publishing MVC application to virtual directory inside default web-site

    - by Michael Sagalovich
    Hi! I am developing an application using ASP.NET MVC 1 and VS2008. When I deploy it to the default web-site in my IIS6 on WinXP, all images are shown correctly, path to any given image is localhost/Content/ImagesUI/[image].[ext] When I deploy it to the virtual directory, created inside the same site, any image request returns IIS standard 404 error page, while the path is localhost/[DirectoryName]/Content/ImagesUI/[image].[ext] - that seems to be correct, true? I am mapping .* to c:\windows\microsoft.net\framework\v2.0.50727\aspnet_isapi.dll in both site and directory configurations. When this mapping is removed, images are shown correctly. However, all other URLs do not work, of course. When I am trying to open an image in browser using the URL to it, aspnet_wp.exe process is not even started (I restarted IIS to test it) - I merely get 404 or the image, depending on the presence of * mapping. Thus, I suppose it has nothing to do neither with routes registered for MVC, nor with ASP. The solution that I found is to make Content folder a virtual directory and remove * mapping from its configuration. While that's OK to some extent, I want a better solution, which will explain and eliminate the cause of the problem, not just workaround it. Thanks for your help!

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  • CSS Container DIV Not Expanding

    - by rsmith84
    I've been researching this for hours now and it seems to be an IE thing but my issue is that I have a container DIV that, in IE9, doesn't expand and cuts everything off after about 400px. Chrome and FF work perfectly, of course. Container DIV #main_container{ font-family: arial, verdana; width: 920px; top: 0; margin-left: auto; margin-right: auto; background-color: #fff; overflow-x: hidden; } Page Container DIV #page_container{ font-family: arial, verdana; font-size: 14px; width: 900px; color: #000; border: 0px solid; overflow: hidden; } And the standard markup of page block looks like this <div id="main_container"> <div id="page_container"> Variable page data goes here </div> </div> Is there an issue with my CSS that I'm missing or is there an IE hack that I need to apply?

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  • Efficient way to get highly correlated pairs from large data set in Python or R

    - by Akavall
    I have a large data set (Let's say 10,000 variables with about 1000 elements each), we can think of it as 2D list, something like: [[variable_1], [variable_2], ............ [variable_n] ] I want to extract highly correlated variable pairs from that data. I want "highly correlated" to be a parameter that I can choose. I don't need all pairs to be extracted, and I don't necessarily want the most correlated pairs. As long as there is an efficient method that gets me highly correlated pairs I am happy. Also, it would be nice if a variable does not show up in more than one pair. Although this might not be crucial. Of course, there is a brute force way to finding such pairs, but it is too slow for me. I've googled around for a bit and found some theoretical work on this issue, but I wasn't able for find a package that could do what I am looking for. I mostly work in python, so a package in python would be most helpful, but if there exists a package in R that does what I am looking for it will be great. Does anyone know of a package that does the above in Python or R? Or any other ideas? Thank You in Advance

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  • own drawImage / drawLine in OpenGL

    - by Chrise
    I'm implementing some native 2D-draw functions in my graphics engine for android, but now there's another question coming up, when I observe the performance of my program. At the moment I'm implementing a drawLine/drawImage function. In summary, there are following different values for drawing each different line / image: the color the alpha value the width of the line rotation (only for images) size/scale (also for images) blending method (subrtract, add, normal-alpha) Now, when an imageLine is drawn, I put the CPU-calculated vertex-positions and uv-values for 6 vertices (2 triangles), into a Floatbuffer and draw it immediately with drawArrays, after passing information for drawing (color,alpha, etc.) via uniforms to the shader. When I draw an image, the pre-set VBO is directly drawn after passing information. The first fact I recognized, is: of course drawing Images is much faster, than imagelines (beacuse of VBOs), but also: I cannot pre-put vertex-data into a VBO for imageLines, because imageLines have no static shape like normal images (varying linelength, varying linewidth and the vertex positions of x1,y1 and x2,y2 change too often) That's why I use a normal Floatbuffer, instead of a VBO. So my question is: What's the best way for managing images, and other 2D-graphics functions. For me it's some kind of important, that the user of the engine is able to draw as many images/2D graphics as possible, without loosing to much performance. You can find the functions for drawing images, imagelines, rects, quads, etc. here: https://github.com/Chrise55/LLama3D/blob/master/Llama3DLibrary/src/com/llama3d/object/graphics/image/ImageBase.java Here an example how it looks with many images (testing artificial neural networks), it works fine, but already little bit slow with that many images... :(

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  • Learning Python else syntax error

    - by user1441016
    Hi I am learning python by doing the practice problems for Open course at MIT 6.00 Intro to Computer Science. I am Trying to do practice problem 1 part 2 create a recursive function to count the instance of key in target. My code so far... from string import * def countSubStringMatchRecursive (target, key,x,s): if (find(target,key)==find(target,key,s)) and (find(target,key)==find(target,key,(find(target,key)))):#if first and last return (1) elif (find(target,key)==find(target,key,s))and (find(target,key)!=find(target,key,(find(target,key)))):#if first but not last x=1 s= find(target,key) return (countSubStringMatchRecursive(target,key,s,x) elif (find(target,key,s))==-1 and (find(target,key)!=find(target,key,s)):#if last but not first return (x+1) elif:(find(target,key,s))!=-1 and (find(target,key)!=find(target,key,s)):#if not last and not first x=x+1 s= find(target,key,s) return (countSubStringMatchRecursive(target,key,s,x) I getting a syntax error at line 8. I would just like to know what I did wrong there. Dont worry about the other mistakes I should be able to get those sorted out. I just Stuck on this. Thanks.

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  • How do I get my Windows Forms application to use a custom main function and get access to the Applic

    - by burble
    Hi Folks I am trying to use a Main () function in a class to control the program flow in my vb .net Windows Forms application. I have added a splash screen component and a login screen, and customised my main sdi form. I have set the startup form to be my main function in the Application Page of the Project Designer, and everything seems to work fine(ish). However, I would like to use: Me.MinimumSplashScreenDisplayTime = 5000 to ensure that the splash screen is visible, but it is not recognised by the system unless I tick the Enable Application Framework check box on the Project Designer. If I do this, on startup the program ignores the login and splash screens and all my customisation and just displays a default Form1, even though I have also specified my splash screen in the AF dropdown list. Of course, there are alternative ways to delay a splash screen, such as putting the thread temporarily to sleep (which didn't seem to work), but I suspect that there are other things in the AF that I may want to use. Any suggestions on how I can get round this please, and get a sensible means of controlling program flow? Any thoughts on the best overall structure for organising program flow would also be helpful too. I am concerned both about going down a Microsoft or an alternative custom route that may cause me problems later, as the application becomes more complex. Thankses.

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  • How can I make this simple C# generics factory work?

    - by Kevin Brassen
    I have this design: public interface IFactory<T> { T Create(); T CreateWithSensibleDefaults(); } public class AppleFactory : IFactory<Apple> { ... } public class BananaFactory : IFactory<Banana> { ... } // ... The fictitious Apple and Banana here do not necessarily share any common types (other than object, of course). I don't want clients to have to depend on specific factories, so instead, you can just ask a FactoryManager for a new type. It has a FactoryForType method: IFactory<T> FactoryForType<T>(); Now you can invoke the appropriate interface methods with something like FactoryForType<Apple>().Create(). So far, so good. But there's a problem at the implementation level: how do I store this mapping from types to IFactory<T>s? The naive answer is an IDictionary<Type, IFactory<T>>, but that doesn't work since there's no type covariance on the T (I'm using C# 3.5). Am I just stuck with an IDictionary<Type, object> and doing the casting manually?

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  • How to deal with unknown entity references?

    - by Chris
    I'm parsing (a lot of) XML files that contain entity references which i dont know in advance (can't change that fact). For example: xml = "<tag>I'm content with &funny; &entity; &references;.</tag>" when i try to parse this using the following code: final DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); final DocumentBuilder db = dbf.newDocumentBuilder(); final InputSource is = new InputSource(new StringReader(xml)); final Document d = db.parse(is); i get the following exception: org.xml.sax.SAXParseException: The entity "funny" was referenced, but not declared. but, what i do want to achieve is, that the parser replaces every entity that is not declared (unknown to the parser) with an empty String ''. Or even better, is there a way to pass a map to the parser like: Map<String,String> entityMapping = ... entityMapping.put("funny","very"); entityMapping.put("entity","important"); entityMapping.put("references","stuff"); so that i could do the following: final DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); final DocumentBuilder db = dbf.newDocumentBuilder(); final InputSource is = new InputSource(new StringReader(xml)); db.setEntityResolver(entityMapping); final Document d = db.parse(is); if i would obtain the text from the document using this example code i should receive: I'm content with very important stuff. Any suggestions? Of course, i already would be happy to just replace the unknown entity's with empty strings. Thanks,

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  • Why is Excel's 'Evaluate' method a general expression evaluator?

    - by jtolle
    A few questions have come up recently involving the Application.Evaluate method callable from Excel VBA. The old XLM macro language also exposes an EVALUATE() function. Both can be quite useful. Does anyone know why the evaluator that is exposed can handle general expressions, though? My own hunch is that Excel needed to give people a way to get ranges from string addresses, and to get the value of named formulas, and just opening a portal to the expression evaluator was the easiest way. (The help for the VBA version does say its purpose it to "convert a Microsoft Excel name to an object or a value".) But of course you don't need the ability to evaluate arbitrary expressions just to do that. (That is, Excel could provide a Name.Evaluate method or something instead.) Application.Evaluate seems kind of...unfinished. It's full behavior isn't very well documented, and there are quite a few quirks and limitations (as described by Charles Williams here: http://www.decisionmodels.com/calcsecretsh.htm) with what is exposed. I suppose the answer could be simply "why not expose it?", but I'd be interested to know what design decisions led to this feature taking the form that it does. Failing that, I'd be interested to hear other hunches.

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  • MySQL: Limit rows linked to each joined row

    - by SolidSnakeGTI
    Hello, Specifications: MySQL 4.1+ I've certain situation that requires certain result set from MySQL query, let's see the current query first & then ask my question: SELECT thread.dateline AS tdateline, post.dateline AS pdateline, MIN(post.dateline) FROM thread AS thread LEFT JOIN post AS post ON(thread.threadid = post.threadid) LEFT JOIN forum AS forum ON(thread.forumid = forum.forumid) WHERE post.postid != thread.firstpostid AND thread.open = 1 AND thread.visible = 1 AND thread.replycount >= 1 AND post.visible = 1 AND (forum.options & 1) AND (forum.options & 2) AND (forum.options & 4) AND forum.forumid IN(1,2,3) GROUP BY post.threadid ORDER BY tdateline DESC, pdateline ASC As you can see, mainly I need to select dateline of threads from 'thread' table, in addition to dateline of the second post of each thread, that's all under the conditions you see in the WHERE CLAUSE. Since each thread has many posts, and I need only one result per thread, I've used GROUP BY CLAUSE for that purpose. This query will return only one post's dateline with it's related unique thread. My questions are: How to limit returned threads per each forum!? Suppose I need only 5 threads -as a maximum- to be returned for each forum declared in the WHERE CLAUSE 'forum.forumid IN(1,2,3)', how can this be achieved. Is there any recommendations for optimizing this query (of course after solving the first point)? Notes: I prefer not to use sub-queries, but if it's the only solution available I'll accept it. Double queries not recommended. I'm sure there's a smart solution for this situation. Appreciated advice in advance :)

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  • Repository Pattern Standardization of methods

    - by Nix
    All I am trying to find out the correct definition of the repository pattern. My original understanding was this (extremely dubmed down) Separate your Business Objects from your Data Objects Standardize access methods in data access layer. I have really seen 2 different implementations. Implementation 1 : public Interface IRepository<T>{ List<T> GetAll(); void Create(T p); void Update(T p); } public interface IProductRepository: IRepository<Product> { //Extension methods if needed List<Product> GetProductsByCustomerID(); } Implementation 2 : public interface IProductRepository { List<Product> GetAllProducts(); void CreateProduct(Product p); void UpdateProduct(Product p); List<Product> GetProductsByCustomerID(); } Notice the first is generic Get/Update/GetAll, etc, the second is more of what I would define "DAO" like. Both share an extraction from your data entities. Which I like, but i can do the same with a simple DAO. However the second piece standardize access operations I see value in, if you implement this enterprise wide people would easily know the set of access methods for your repository. Am I wrong to assume that the standardization of access to data is an integral piece of this pattern ? Rhino has a good article on implementation 1, and of course MS has a vague definition and an example of implementation 2 is here.

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  • Is NFS capable of preserving order of operations?

    - by JustJeff
    I have a diskless host 'A', that has a directory NFS mounted on server 'B'. A process on A writes to two files F1 and F2 in that directory, and a process on B monitors these files for changes. Assume that B polls for changes faster than A is expected to make them. Process A seeks the head of the files, writes data, and flushes. Process B seeks the head of the files and does reads. Are there any guarantees about how the order of the changes performed by A will be detected at B? Specifically, if A alternately writes to one file, and then the other, is it reasonable to expect that B will notice alternating changes to F1 and F2? Or could B conceivably detect a series of changes on F1 and then a series on F2? I know there are a lot of assumptions embedded in the question. For instance, I am virtually certain that, even operating on just one file, if A performs 100 operations on the file, B may see a smaller number of changes that give the same result, due to NFS caching some of the actions on A before they are communicated to B. And of course there would be issues with concurrent file access even if NFS weren't involved and both the reading and the writing process were running on the same real file system. The reason I'm even putting the question up here is that it seems like most of the time, the setup described above does detect the changes at B in the same order they are made at A, but that occasionally some events come through in transposed order. So, is it worth trying to make this work? Is there some way to tune NFS to make it work, perhaps cache settings or something? Or is fine-grained behavior like this just too much expect from NFS?

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  • Adding a column to a model at runtime (without additional tables) in rails

    - by Marek
    I'm trying to give admins of my web application the ability to add some new fields to a model. The model is called Artwork and i would like to add, for instante, a test_column column at runtime. I'm just teting, so i added a simple link to do it, it will be of course parametric. I managed to do it through migrations: def test_migration_create Artwork.add_column :test_column, :integer flash[:notice] = "Added Column test_column to artworks" redirect_to :action => 'index' end def test_migration_delete Artwork.remove_column :test_column flash[:notice] = "Removed column test_column from artworks" redirect_to :action => 'index' end It works, the column gets added/ removed to/from the databse without issues. I'm using active_scaffold at the moment, so i get the test_column field in the form without adding anything. When i submit a create or an update, however, the test_column does not get updated and stay empty. Inspecting the parameters, i can see: Parameters: {"commit"=>"Update", "authenticity_token"=>"37Bo5pT2jeoXtyY1HgkEdIhglhz8iQL0i3XAx7vu9H4=", "id"=>"62", "record"=>{"number"=>"test_artwork", "author"=>"", "title"=>"Opera di Test", "test_column"=>"TEEST", "year"=>"", "description"=>""}} the test_column parameter is passed correctly. So why active record keeps ignoring it? I tried to restart the server too without success. I'm using ruby 1.8.7, rails 2.3.5, and mongrel with an sqlite3 database. Thanks

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  • How to further improve error messages in Scala parser-combinator based parsers?

    - by rse
    I've coded a parser based on Scala parser combinators: class SxmlParser extends RegexParsers with ImplicitConversions with PackratParsers { [...] lazy val document: PackratParser[AstNodeDocument] = ((procinst | element | comment | cdata | whitespace | text)*) ^^ { AstNodeDocument(_) } [...] } object SxmlParser { def parse(text: String): AstNodeDocument = { var ast = AstNodeDocument() val parser = new SxmlParser() val result = parser.parseAll(parser.document, new CharArrayReader(text.toArray)) result match { case parser.Success(x, _) => ast = x case parser.NoSuccess(err, next) => { tool.die("failed to parse SXML input " + "(line " + next.pos.line + ", column " + next.pos.column + "):\n" + err + "\n" + next.pos.longString) } } ast } } Usually the resulting parsing error messages are rather nice. But sometimes it becomes just sxml: ERROR: failed to parse SXML input (line 32, column 1): `"' expected but `' found ^ This happens if a quote characters is not closed and the parser reaches the EOT. What I would like to see here is (1) what production the parser was in when it expected the '"' (I've multiple ones) and (2) where in the input this production started parsing (which is an indicator where the opening quote is in the input). Does anybody know how I can improve the error messages and include more information about the actual internal parsing state when the error happens (perhaps something like a production rule stacktrace or whatever can be given reasonably here to better identify the error location). BTW, the above "line 32, column 1" is actually the EOT position and hence of no use here, of course.

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  • better understanding of getline() and cin

    - by numerical25
    Trying to get some basic understanding of console functionalities. I am having issues so consider the following... #include "stdafx.h" #include<iostream> #include<conio.h> using namespace std; /* This is a template Project */ void MultiplicationTable(int x); int main() { int value = 0; printf("Please enter any number \n\n"); getline(cin, value); MultiplicationTable(value); getchar(); return 0; } I actually based this off code from http://www.cplusplus.com/doc/tutorial/basic_io/ . My IDE is not recognizing getline() so of course when I compile the application. I get an error 'getline': identifier not found Now take a look at this code #include "stdafx.h" #include<iostream> #include<conio.h> using namespace std; /* This is a template Project */ void MultiplicationTable(int x); int main() { int value = 0; printf("Please enter any number \n\n"); cin>>value; MultiplicationTable(value); getchar(); return 0; } When I execute this line of code the console window opens and immediately closes. I think I a missing something about cin. I do know that it delimits spaces but I don't know what else. what should I use for input to make my life easier.

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  • how to fill missing values from a list

    - by Stephane
    I have an object containing a date and a count. public class Stat { public DateTime Stamp {get; set;} public int Count {get; set ;} } I have a Serie object that holds a list of thoses Stat plus some more info such as name and so on... public class Serie { public string Name { get; set; } public List<Stat> Data { get; set; } ... } Consider that I have a List of Serie but the series don't all contain the same Stamps. I need to fill in the missing stamps in all series with a default value. I thought of an extension method with signature like this (please provide better name if you find one :) ) : public static IEnumerable<Serie> Equalize(this IEnumerable<ChartSerie> series, int defaultCount) this question seems to treat the same problem, but when querying directly the DB. of course I could loop through the dates and create another list. But is there any more elegant way to achieve this? i.e.: Serie A: 01.05.2010 1 03.05.2010 3 Serie B: 01.05.2010 5 02.05.2010 6 I should get : Serie A : 01.05.2010 1 02.05.2010 0 03.05.2010 3 Serie B: 01.05.2010 5 02.05.2010 6 03.05.2010 0

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  • ggplot: showing % instead of counts in charts of categorical variables

    - by wishihadabettername
    I'm plotting a categorical variable and instead of showing the counts for each category value, I'm looking for a way to get ggplot to display the percentage of values in that category. Of course, it is possible to create another variable with the calculated percentage and plot that one, but I have to do it several dozens of times and I hope to achieve that in one command. I was experimenting with something like qplot (mydataf) + stat_bin(aes(n=nrow(mydataf), y=..count../n)) + scale_y_continuous(formatter="percent") but I must be using it incorrectly, as I got errors. To easily reproduce the setup, here's a simplified example: mydata <- c ("aa", "bb", null, "bb", "cc", "aa", "aa", "aa", "ee", null, "cc"); mydataf <- factor(mydata); qplot (mydataf); #this shows the count, I'm looking to see % displayed. In the real case I'll probably use ggplot instead of qplot, but the right way to use stat_bin still eludes me. Thank you. UPDATE: I've also tried these four approaches: ggplot(mydataf, aes(y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent'); ggplot(mydataf, aes(y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent') + geom_bar(); ggplot(mydataf, aes(x = levels(mydataf), y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent'); ggplot(mydataf, aes(x = levels(mydataf), y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent') + geom_bar(); but all 4 give: Error: ggplot2 doesn't know how to deal with data of class factor The same error appears for the simple case of ggplot (data=mydataf, aes(levels(mydataf))) + geom_bar() so it's clearly something about how ggplot interacts with a single vector. I'm scratching my head, googling for that error gives a single result.

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  • Click at specified client area

    - by VixinG
    Click doesn't work - I don't know why and can't find a solution :( ie. Click(150,215) should move mouse to the client area and click there. [DllImport("user32.dll")] private static extern bool ScreenToClient(IntPtr hWnd, ref Point lpPoint); [DllImport("user32", SetLastError = true)] private static extern int SetCursorPos(int x, int y); static void MouseMove(int x, int y) { Point p = new Point(x * -1, y * -1); ScreenToClient(hWnd, ref p); p = new Point(p.X * -1, p.Y * -1); SetCursorPos(p.X, p.Y); } static void Click(int x, int y) { MouseMove(x, y); SendMessage(hWnd, WM_LBUTTONDOWN, (IntPtr)0x1, new IntPtr(y * 0x10000 + x)); SendMessage(hWnd, WM_LBUTTONUP, (IntPtr)0x1, new IntPtr(y * 0x10000 + x)); } Edit: Of course I can use mouse_event for that, but I would like to see a solution for SendMessage()... [DllImport("user32.dll")] static extern void mouse_event(int dwFlags, int dx, int dy, int dwData, int dwExtraInfo); const int LEFTDOWN = 0x00000002; const int LEFTUP = 0x00000004; static void Click(int x, int y) { MouseMove(x, y); mouse_event((int)(LEFTDOWN), 0, 0, 0, 0); mouse_event((int)(LEFTUP), 0, 0, 0, 0); }

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  • Code management in different projects with different svn repositories

    - by uzay95
    First of all I want to tell you what kind of system I have and I want to build on. 1- A Solution (has) a- Shared Class Library project (which is for lots of different solutions) b- Another Class Library project (which is only for this solution) c- Web Application project (which main part of this solution) d- Shared Web Service project (which also serves for different solutions) 2- B Solution (has) a- Shared Class Library project (which is for lots of different solutions) c- Windows Form Application project (which is main part of this solution) d- Web Service project (which also serves for different solutions) and other projects like that.... I am using xp-dev.com as our svn repository server. And I opened different projects for these items (Shared Class Library, Web Service project, Windows Form Application project, Web Application project, Another Class Library project) . I want to do the versioning of all these projects of course. My first question is, should I put each project(one solution) to one svn repository to get their revision number later on? Or should I put each of them to different svn repository and keep( write down) their correct version number that is used to publish/deploy every solution? If I use one svn for each project(Shared Class Lib, Web App, Shared Web Service....) how can I relate the right svn address and version on VS.2010 within the real solution? So, how do you manage your repositories and projects?

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  • What do you call a set of Javascript closures that share a common context?

    - by Ed Stauff
    I've been trying to learn closures (in Javascript), which kind of hurts my brain after way too many years with C# and C++. I think I now have a basic understanding, but one thing bothers me: I've visited lots of websites in this Quest for Knowledge, and nowhere have I seen a word (or even a simple two-word phrase) that means "a set of Javascript closures that share a common execution context". For example: function CreateThingy (name, initialValue) { var myName = name; var myValue = initialValue; var retObj = new Object; retObj.getName = function() { return myName; } retObj.getValue = function() { return myValue; } retObj.setValue = function(newValue) { myValue = newValue; } return retObj; }; From what I've read, this seems to be one common way of implementing data hiding. The value returned by CreateThingy is, of course, an object, but what would you call the set of functions which are properties of that object? Each one is a closure, but I'd like a name I can used to describe (and think about) all of them together as one conceptual entity, and I'd rather use a commonly accepted name than make one up. Thanks! -- Ed

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  • Stable/repeatable random sort (MySQL, Rails)

    - by Matt Rogish
    I'd like to paginate through a randomly sorted list of ActiveRecord models (rows from MySQL database). However, this randomization needs to persist on a per-session basis, so that other people that visit the website also receive a random, paginate-able list of records. Let's say there are enough entities (tens of thousands) that storing the randomly sorted ID values in either the session or a cookie is too large, so I must temporarily persist it in some other way (MySQL, file, etc.). Initially I thought I could create a function based on the session ID and the page ID (returning the object IDs for that page) however since the object ID values in MySQL are not sequential (there are gaps), that seemed to fall apart as I was poking at it. The nice thing is that it would require no/minimal storage but the downsides are that it is likely pretty complex to implement and probably CPU intensive. My feeling is I should create an intersection table, something like: random_sorts( sort_id, created_at, user_id NULL if guest) random_sort_items( sort_id, item_id, position ) And then simply store the 'sort_id' in the session. Then, I can paginate the random_sorts WHERE sort_id = n ORDER BY position LIMIT... as usual. Of course, I'd have to put some sort of a reaper in there to remove them after some period of inactivity (based on random_sorts.created_at). Unfortunately, I'd have to invalidate the sort as new objects were created (and/or old objects being removed, although deletion is very rare). And, as load increases the size/performance of this table (even properly indexed) drops. It seems like this ought to be a solved problem but I can't find any rails plugins that do this... Any ideas? Thanks!!

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  • Alert and if changes behaviour dom copying

    - by lowkey
    Hi guys! Tried to make a little old school ajax (iframe-javascript) script. A bit of mootools is used for DOM navigation Description: HTML: 1 iframe called "buffer" 1 div called "display" JAVASCRIPT: (short: copy iframe content into a div on the page) 1) onLoad on iframe triggers handler(), a counter makes sure it only run once (this is because otherwise firefox will go into feedback loop. What i think happens: iframe on load handler() copyBuffer change src of iframe , and firefox takes that as an onload again) 2) copybuffer() is called, it sets src of iframe then copies iframe content into div, then erases iframe content THE CODE: count=0; function handler(){ if (count==0){ copyBuffer(); count++; } } function copyBuffer(){ $('buffer').set('src','http://www.somelink.com/'); if (window.frames['buffer'] && $('display') ) { $('display').innerHTML = window.frames['buffer'].document.body.innerHTML; window.frames['buffer'].document.body.innerHTML=""; } } problems: QUESTION 1) nothing happens, the content is not loaded into the div. But if i either: A) remove the counter and let the script run in a feedback loop: the content is suddenly copied into the div, but off course there is a feedback loop going on, you can see it keeps loading in the status bar. OR B) insert an alert in the copyBuffer function. The content is copied, without the feedback loop. why does this happen? QUESTION 2) The If wrapped around the copying code i got from a source on the internet. I am not sure what it does? If i remove it the code does not work in: Safari and Chrome. Many thanks in advance!

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  • Listing all objects that share a common variable in Javascript

    - by ntgCleaner
    I'm not exactly sure how to ask this because I am just learning OOP in Javascript, but here it goes: I am trying to be able to make a call (eventually be able to sort) for all objects with the same variable. Here's an example below: function animal(name, numLegs, option2, option3){ this.name = name; this.numLegs = numLegs; this.option2 = option2; this.option3 = option3; } var human = new animal(Human, 2, example1, example2); var horse = new animal(Horse, 4, example1, example2); var dog = new animal(Dog, 4, example1, example2); Using this example, I would like to be able to do a console.log() and show all animal NAMES that have 4 legs. (Should only show Horse and Dog, of course...) I eventually want to be able to make a drop-down list or a filtered search list with this information. I would do this with php and mySQL but I'm doing this for the sake of learning OOP in javascript. I only ask here because I don't exactly know what to ask. Thank you!

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