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  • C++: best way to implement globally scoped data

    - by bobobobo
    I'd like to make program-wide data in a C++ program, without running into pesky LNK2005 errors when all the source files #includes this "global variable repository" file. I have 2 ways to do it in C++, and I'm asking which way is better. The easiest way to do it in C# is just public static members. C#: public static class DataContainer { public static Object data1 ; public static Object data2 ; } In C++ you can do the same thing C++ global data way#1: class DataContainer { public: static Object data1 ; static Object data2 ; } ; Object DataContainer::data1 ; Object DataContainer::data2 ; However there's also extern C++ global data way #2: class DataContainer { public: Object data1 ; Object data2 ; } ; extern DataContainer * dataContainer ; // instantiate in .cpp file In C++ which is better, or possibly another way which I haven't thought about? The solution has to not cause LNK2005 "object already defined" errors.

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  • Drawing an image is completely out

    - by ct2k7
    Hi I'm using this code below to let a user "draw" their signature on a UIView component on my app: UIGraphicsBeginImageContext(signature.frame.size); [drawImage.image drawInRect:CGRectMake(0, 0, signature.frame.size.width, signature.frame.size.height)]; CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound); CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 5.0); CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1.0, 0.0, 0.0, 1.0); CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y); CGContextStrokePath(UIGraphicsGetCurrentContext()); CGContextFlush(UIGraphicsGetCurrentContext()); drawImage.image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext() The issue I am having is that the drawing is not only is the drawing not in line with the pointer when in use in the simulator, the image is going outside of the designated UIView compontent and is getting smaller/out of focus the more I draw, as you can see in this image: And after a few lines, showing the boundaries of the exact are of where I can draw: Any ideas on what's happening here? lastPoint.y is defined as: lastPoint.y -= 20; Any ideas on what on earth is happening here?

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  • cancelPreviousPerformRequestWithTarget is not canceling my previously delayed thread started with pe

    - by jmurphy
    Hello, I've launched a delayed thread using performSelector but the user still has the ability to hit the back button on the current view causing dealloc to be called. When this happens my thread still seems to be called which causes my app to crash because the properties that thread is trying to write to have been released. To solve this I am trying to call cancelPreviousPerformRequestsWithTarget to cancel the previous request but it doesn't seem to be working. Below are some code snippets. - (void) viewDidLoad { [self performSelector:@selector(myStopUpdatingLocation) withObject:nil afterDelay:6]; } (void)viewWillDisappear:(BOOL)animated { [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(myStopUpdatingLocation) object:nil]; } Am I doing something incorrect here? The method myStopUpdatingLocation is defined in the same class that I'm calling the perform requests. A little more background. The function that I'm trying to implement is to find a users location, search google for some locations around that location and display several annotations on the map. On viewDidLoad I start updating the location with CLLocationManager. I've build in a timeout after 6 seconds if I don't get my desired accuracy within the timeout and I'm using a performSelector to do this. What can happen is the user clicks the back button in the view and this thread will still execute even though all my properties have been released causing a crash. Thanks in advance! James

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  • Unsort: remembering a permutation and undoing it.

    - by dreeves
    Suppose I have a function f that takes a vector v and returns a new vector with the elements transformed in some way. It does that by calling function g that assumes the vector is sorted. So I want f to be defined like so: f[v_] := Module[{s, r}, s = Sort[v]; (* remember the permutation applied in order to sort v *) r = g[s]; Unsort[r] (* apply the inverse of that permutation *) ] What's the best way to do the "Unsort"? Or could we get really fancy and have this somehow work: answer = Unsort[g[Sort[v]]]; ADDED: Let's make this concrete with a toy example. Suppose we want a function f that takes a vector and transforms it by adding to each element the next smallest element, if any. That's easy to write if we assume the vector is sorted, so let's write a helper function g that makes that assumption: g[v_] := v + Prepend[Most@v, 0] Now for the function we really want, f, that works whether or not v is sorted: f[v_] := (* remember the order; sort it; call g on it; put it back in the original order; return it *)

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  • What makes people think that NNs have more computational power than existing models?

    - by Bubba88
    I've read in Wikipedia that neural-network functions defined on a field of arbitrary real/rational numbers (along with algorithmic schemas, and the speculative `transrecursive' models) have more computational power than the computers we use today. Of course it was a page of russian wikipedia (ru.wikipedia.org) and that may be not properly proven, but that's not the only source of such.. rumors Now, the thing that I really do not understand is: How can a string-rewriting machine (NNs are exactly string-rewriting machines just as Turing machines are; only programming language is different) be more powerful than a universally capable U-machine? Yes, the descriptive instrument is really different, but the fact is that any function of such class can be (easily or not) turned to be a legal Turing-machine. Am I wrong? Do I miss something important? What is the cause of people saying that? I do know that the fenomenum of undecidability is widely accepted today (though not consistently proven according to what I've read), but I do not really see a smallest chance of NNs being able to solve that particular problem. Add-in: Not consistently proven according to what I've read - I meant that you might want to take a look at A. Zenkin's (russian mathematician) papers after mid-90-s where he persuasively postulates the wrongness of G. Cantor's concepts, including transfinite sets, uncountable sets, diagonalization method (method used in the proof of undecidability by Turing) and maybe others. Even Goedel's incompletness theorems were proven in right way in only 21-st century.. That's all just to plug Zenkin's work to the post cause I don't know how widespread that knowledge is in CS community so forgive me if that did look stupid. Thank you!

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  • SSH with Perl using file handles, not Net::SSH

    - by jorge
    Before I ask the question: I can not use cpan module Net::SSH, I want to but can not, no amount of begging will change this fact I need to be able to open an SSH connection, keep it open, and read from it's stdout and write to its stdin. My approach thus far has been to open it in a pipe, but I have not been able to advance past this, it dies straight away. That's what I have in mind, I understand this causes a fork to occur. I've written code accordingly for this fork (or so I think). Below is a skeleton of what I want, I just need the system to work. #!/usr/bin/perl use warnings; $| = 1; $pid = open (SSH,"| ssh user\@host"); if(defined($pid)){ if(!$pid){ #child while(<>){ print; } }else{ select SSH; $| = 1; select STDIN; #parent while(<>){ print SSH $_; while(<SSH>){ print; } } close(SSH); } } I know, from what it looks like, I'm trying to recreate "system('ssh user@host')," that is not my end goal, but knowing how to do that would bring me much closer to the end goal. Basically, I need a file handle to an open ssh connection where I can read from it the output and write to it input (not necessarily straight from my program's STDIN, anything I want, variables, yada yada) This includes password input. I know about key pairs, part of the end goal involves making key pairs, but the connection needs to happen regardless of their existence, and if they do not exist it's part of my plan to make them exist.

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  • Antlr MismatchedSetException During Interpretation

    - by user1646481
    I am new to Antlr and I have defined a basic grammar using Antlr 3. The grammar compiles and ANTLRWorks generates the Parser and Lexer code without any problems. The grammar can be seen below: grammar i; @header { package i; } module : 'Module1'| 'Module2'; object : 'I'; objectType : 'Name'; filters : EMPTY | 'WHERE' module; table : module object objectType; STRING : ('a'..'z'|'A'..'Z')+; EMPTY : ' '; The problem is that when I interpret the table Parser I get a MismatchedSetException. This is due to having the EMPTY. As soon as I remove EMPTY from the grammar, the interpretation works. I have looked on the Antlr website and some other examples and the Empty space is ' '. I am not sure what to do. I need this EMPTY. As soon as I change the EMPTY to be the following: EMPTY : ''; instead of: EMPTY : ' '; It actually interprets it. However, I am getting the following Exception: Interpreting... [10:57:23] problem matching token at 1:4 NoViableAltException(' '@[1:1: Tokens : ( T__4 | T__5 | T__6 | T__7 | T__8 | T__9 | T__10 | T__11 | T__12 | T__13 | T__14 | T__15 | T__16 );]) [10:57:23] problem matching token at 1:9 NoViableAltException(' '@[1:1: Tokens : ( T__4 | T__5 | T__6 | T__7 | T__8 | T__9 | T__10 | T__11 | T__12 | T__13 | T__14 | T__15 | T__16 );]) When I take out the EMPTY, there are no problems at all. I hope you can help.

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  • Grails g:paginate tag and custom URL

    - by aboxy
    Hello, I am trying to use g:paginate in a shared template where depending on the controller, url changes e.g. For my homepage url should be : mydomain[DOT]com/news/recent/(1..n) For search Page: www[DOT]mydomain[DOT]com/search/query/"ipad apps"/filter/this month and my g:paginate looks like this: g:paginate controller=${customeController} action=${customAction} total:${total} For the first case, I was able to provide controller as 'news' and action as 'recent' and mapped url /news/recent/$offset to my controller. But for the search page, I am not able to achieve what I want to do. I have a URL mapping defined as /search/$filter**(controller:"search",action:"fetch") $filter can be /query/"ipad apps"/filter/thismonth/filter/something/filter/somethingelse. I want to be able to show the url as above rather than ?query="ipad apps"&filter=thismonth&filter=something&filter=somethingelse. I believe I can pass all the parameters in params attribute of g:paginate but that will not give me pretty URL. What would be the best way to achieve this? Please feel free to ask questions If i missed anything.Thanks in advance.

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  • Common Lisp condition system for transfer of control

    - by Ken
    I'll admit right up front that the following is a pretty terrible description of what I want to do. Apologies in advance. Please ask questions to help me explain. :-) I've written ETLs in other languages that consist of individual operations that look something like: // in class CountOperation IEnumerable<Row> Execute(IEnumerable<Row> rows) { var count = 0; foreach (var row in rows) { row["record number"] = count++; yield return row; } } Then you string a number of these operations together, and call The Dispatcher, which is responsible for calling Operations and pushing data between them. I'm trying to do something similar in Common Lisp, and I want to use the same basic structure, i.e., each operation is defined like a normal function that inputs a list and outputs a list, but lazily. I can define-condition a condition (have-value) to use for yield-like behavior, and I can run it in a single loop, and it works great. I'm defining the operations the same way, looping through the inputs: (defun count-records (rows) (loop for count from 0 for row in rows do (signal 'have-value :value `(:count ,count @,row)))) The trouble is if I want to string together several operations, and run them. My first attempt at writing a dispatcher for these looks something like: (let ((next-op ...)) ;; pick an op from the set of all ops (loop (handler-bind ((have-value (...))) ;; records output from operation (setq next-op ...) ;; pick a new next-op (call next-op))) But restarts have only dynamic extent: each operation will have the same restart names. The restart isn't a Lisp object I can store, to store the state of a function: it's something you call by name (symbol) inside the handler block, not a continuation you can store for later use. Is it possible to do something like I want here? Or am I better off just making each operation function explicitly look at its input queue, and explicitly place values on the output queue?

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  • QT4 Designer - Implement Widget

    - by MOnsDaR
    I'm currently trying to get into QT4 and figure out a workflow for myself. While trying to create a widget which allows the user to connect to a hostname:port some questions appeared. The widget itself contains a LineEdit for entering the hostname, a SpinBox for entering the port and a PushButton which should emit a connect(QString hostname, unsigned int port) signal. In QTDesigner I created the necessary Form. It is saved as a .ui-File. Now the big question is how could I implement the widget? Is there a place in QTDesigner where I could add my signal to the Widget? Where could I add custom Properties? I've learned in another tutorial, which showed how to create a Widget in C++, how signals, slots, Q_PROPERTIES etc are defined and added to the widget. But there is no sourcecode in QTDesigner. Another option would be to generate sourcecode using uic. But the header says, that another generate would overwrite any changes to the sourcefiles. So how can I create a QT-widget completely with my own signals, slots and properties by using the QTDesigner for creating the UI and not having to recode everything whenever the UI is changing. Is there some kind of Roundtrip-Engineering? If thats not possible: Whats the sense of creating a Widget with QTDesigner then?

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  • Why not put all braces inline in C++/C#/Java/javascript etc.?

    - by DanM
    Of all the conventions out there for positioning braces in C++, C#, Java, etc., I don't think I've ever seen anyone try to propose something like this: public void SomeMethod(int someInput, string someOtherInput) { if (someInput > 5) { var addedNumber = someInput + 5; var subtractedNumber = someInput - 5; } else { var addedNumber = someInput + 10; var subtractedNumber = someInput; } } public void SomeOtherMethod(int someInput, string someOtherInput( { ... } But why not? I'm sure it would take some getting used to, but I personally don't have any difficulty following what's going on here. I believe indentation is the dominant factor in being able to see how code is organized into blocks and sub-blocks. Braces are just visual noise to me. They are these ugly things that take up lines where I don't want them. Maybe I just feel that way because I was weened on basic (and later VB), but I just don't like braces taking up lines. If I want a gap between blocks, I can always add an empty line, but I don't like being forced to have gaps simply because the convention says the closing brace needs to be on its own line. I made this a community wiki because I realize this is not a question with a defined answer. I'm just curious what people think. I know that no one does this currently (at least, not that I've seen), and I know that the auto-formatter in my IDE doesn't support it, but are there are any other solid reasons not to format code this way, assuming you are working with a modern IDE that color codes and auto-indents? Are there scenarios where it will become a readability nightmare? Better yet, are you aware of any research on this?

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  • Constructor Overloading

    - by Mark Baker
    Normally when I want to create a class constructor that accepts different types of parameters, I'll use a kludgy overloading principle of not defining any args in the constructor definition: e.g. for an ECEF coordinate class constructor, I want it to accept either $x, $y and $z arguments, or to accept a single array argument containg x, y and z values, or to accept a single LatLong object I'd create a constructor looking something like: function __construct() { // Identify if any arguments have been passed to the constructor if (func_num_args() > 0) { $args = func_get_args(); // Identify the overload constructor required, based on the datatype of the first argument $argType = gettype($args[0]); switch($argType) { case 'array' : // Array of Cartesian co-ordinate values $overloadConstructor = 'setCoordinatesFromArray'; break; case 'object' : // A LatLong object that needs converting to Cartesian co-ordinate values $overloadConstructor = 'setCoordinatesFromLatLong'; break; default : // Individual Cartesian co-ordinate values $overloadConstructor = 'setCoordinatesFromXYZ'; break; } // Call the appropriate overload constructor call_user_func_array(array($this,$overloadConstructor),$args); } } // function __construct() I'm looking at an alternative: to provide a straight constructor with $x, $y and $z as defined arguments, and to provide static methods of createECEFfromArray() and createECEFfromLatLong() that handle all the necessary extraction of x, y and z; then create a new ECEF object using the standard constructor, and return that Which option is cleaner from an OO purists perspective?

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  • Iframe/Popup redirecting opener window

    - by Bara
    Hello all, I have a page located at x.com. On this page is a button that, when clicked, will launch a new window (using javascript's window.open() method) to a page that is located at z.com. The popup does a few things, then redirects the original window (the opener, x.com) to a different page based on some parameters defined in the popup. This works fine in Firefox/Chrome, but not in IE. In IE (8 specifically, but I believe 7 also has this problem) the original window (the opener) is not redirected. Instead, a new window comes up and THAT window is redirected. I've tried many different methods to try and get this to work, including changing the popup to an iframe loaded on the page and having a function on the opener that the popup/iframe call. The problem seems to be that IE refuses to allow cross-domain sites to talk to each other via javascript. Is there a way around this? How can I get the parent window to redirect to a page based on parameters in a popup or iframe? Bara

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  • RSpec: Can't convert Image to String when using Nested Resource.

    - by darrint
    I'm having trouble with and RSpec view test. I'm using nested resources and the model with a belongs_to association. Here's what I have so far: describe "/images/edit.html.erb" do include ImagesHelper before(:each) do @image_pool = stub_model(ImagePool, :new_record => false, :base_path => '/') assigns[:image] = @image = stub_model(Image, :new_record? => false, :source_name => "value for source_name", :image_pool => @image_pool) end it "renders the edit image form" do render response.should have_tag("form[action=#{image_path(@image)}][method=post]") do with_tag('input#image_source_name[name=?]', "image[source_name]") end end end The error I'm receiving: ActionView::TemplateError in '/images/edit.html.erb renders the edit image form' can't convert Image into String On line #3 of app/views/images/edit.html.erb 1: <h1>Editing image</h1> 2: 3: <% form_for(@image) do |f| %> 4: <%= f.error_messages %> 5: 6: <p> app/views/images/edit.html.erb:3 /opt/dtcm/railstest/lib/ruby/gems/1.9.1/gems/rspec-rails-1.3.2/lib/spec/rails/extensions/action_view/base.rb:27:in `render_with_mock_proxy' /opt/dtcm/railstest/lib/ruby/gems/1.9.1/gems/rspec-rails-1.3.2/lib/spec/rails/example/view_example_group.rb:170:in `render' Looking at the rails code where the exception occurs is not very revealing. Any ideas on how I can narrow down what is going on here? One thing I tried was calling form_for directly from the example and I got a different error griping about lack of 'polymorphic_path' defined on Spec::Rails::Example::ViewExampleGroup::Subclass_4:0xblah. Not sure if that actually means anything.

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  • c# multi inheritance

    - by user326839
    So ive got a base class which requires a Socket: class Sock { public Socket s; public Sock(Socket s) { this.s = s; } public virtual void Process(byte[] data) { } ... } then ive got another class. if a new socket gets accepted a new instance of this class will be created: class Game : Sock { public Random Random = new Random(); public Timerr Timers; public Test Test; public Game(Socket s) : base(s) { } public static void ReceiveNewSocket(object s) { Game Client = new Game((Socket)s); Client.Start(); } public override void Process(byte[] buf) { Timers = new Timerr(s); Test = new Test(s); Test.T(); } } in the Sock class ive got a virtual function that gets overwritten by the Game class.(Process function) in this function im calling a function from the Test Class(Test+ Timerr Class: class Test : Game { public Test(Socket s) : base(s) { } public void T() { Console.WriteLine(Random.Next(0, 10)); Timers.Start(); } } class Timerr : Game { public Timerr(Socket s) : base(s) { } public void Start() { Console.WriteLine("test"); } } ) So in the Process function im calling a function in Test. And in this function(T) i need to call a function from the Timerr Class.But the problem is its always NULL , although the constructor is called in Process. And e.g. the Random Class can be called, i guess its because its defined with the constructor.: public Random Random = new Random(); and thats why the other classes(without a constructor): public Timerr Timers; public Test Test; are always null in the inherited class Test.But its essentiel that i call other Methods of other classes in this function.How could i solve that?

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  • What is the equivalent to Master Views from ASP.NET in PHP?

    - by KingNestor
    I'm used to working in ASP.NET / ASP.NET MVC and now for class I have to make a PHP website. What is the equivalent to Master Views from ASP.NET in the PHP world? Ideally I would like to be able to define a page layout with something like: Master.php <html> <head> <title>My WebSite</title> <?php headcontent?> </head> <body> <?php bodycontent?> </body> </html> and then have my other PHP pages inherit from Master, so I can insert into those predefined places. Is this possible in PHP? Right now I have the top half of my page defined as "Header.html" and the bottom half is "footer.html" and I include_once both of them on each page I create. However, this isn't ideal for when I want to be able to insert into multiple places on my master page such as being able to insert content into the head. Can someone skilled in PHP point me in the right direction?

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  • Finding the Column Index for a Specific Value

    - by Btibert3
    Hi All, I am having a brain cramp. Below is a toy dataset: df <- data.frame( id = 1:6, v1 = c("a", "a", "c", NA, "g", "h"), v2 = c("z", "y", "a", NA, "a", "g"), stringsAsFactors=F) I have a specific value that I want to find across a set of defined columns and I want to identify the position it is located in. The fields I am searching are characters and the trick is that the value I am looking for might not exist. In addition, null strings are also present in the dataset. Assuming I knew how to do this, the variable position indicates the values I would like returned. > df id v1 v2 position 1 1 a z 1 2 2 a y 1 3 3 c a 2 4 4 <NA> <NA> 99 5 5 g a 2 6 6 h g 99 The general rule is that I want to find the position of value "a", and if it is not located or if v1 is missing, then I want 99 returned. In this instance, I am searching across v1 and v2, but in reality, I have 10 different variables. It is also worth noting that the value I am searching for can only exist once across the 10 variables. What is the best way to generate this recode? Many thanks in advance.

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  • Basic PHP OOPS Query

    - by appu
    Ok. I am starting out OOPS in PHP. Created a couple of classes: customer(parent) and sales(child) class that inherits from parent class. Created another testcustomer.php in which a new sales object is created however the salesprint() function defined in the sales class does not echo out customer's name though it is set to be "Jane" in the class.customer.php(parent). My thinking is that when sales class extends customer class PHP automatically includes all the code from class.customer.php to sales.customer.php and therefore the constructor in parent class set $name to "Jane". Here is the code: class.customer.php <?php class customer{ private $name; private $cust_no; public function __construct($customerid) { $this->name = 'Jane'; $this->cust_no = $customerid; } } ?> class.sales.php <?php require_once('class.customer.php'); class sales extends customer{ public function salesprint($customerid) { echo "Hello $this->name this is a print of your purchased products"; } } ?> testcustomer.php require_once('class.sales.php'); $objsales = new sales(17); $objsales->salesprint(17); ?> The Output I get Hello this is a print of your purchased products. What am i doing wrong ? thanks romesh

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  • How to debug an external library (OpenCV) in Visual C++?

    - by neuviemeporte
    I am developing a project in VC++2008. The project uses the OpenCV library (but I guess this applies to any other library). I am working with the Debug configuration, the linker properties include the debug versions of the library .lib's as additional dependencies. In VC++ Directories under Tools|Options i set up the include directory, the .lib directory, the source directories for the library as well. I get an error while calling one of the functions from the library and I'd like to see exactly what that function is doing. The line that produces the error is: double error = cvStereoCalibrate(&calObjPointsM, &img1PointsM, &img2PointsM, &pointCountsM, &cam1M, &dist1M, &cam2M, &dist2M, imgSize, &rotM, &transM, NULL, NULL, cvTermCriteria(CV_TERMCRIT_ITER + CV_TERMCRIT_EPS, 100, 1e-5)); I set up a breakpoint at this line to see how the cvStereoCalibrate() function fails. Unfortunately the debugger won't show the source code for this function when I hit "Step into". It skips immediately to the cvTermCriteria() (which is a simple inline, macro-kinda function) and show its contents. Is there anything else I need to do to be able to enter the external library functions in the debugger? EDIT: I think the cvTermCriteria() function shows in the debugger, because it's defined in a header file, therefore immediately accesible to the project.

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  • how to place dropdown list box in jquery grid column

    - by kumar
    Hello friends, I have a jquery grid columns defined like this.. using System; using System.Collections.Generic; using System.Linq; using System.Web; using Trirand.Web.Mvc; using System.Web.UI.WebControls; namespace JQGridMVCExamples.Models { public class OrdersJqGridModel { public OrdersJqGridModel() { OrdersGrid = new JQGrid { Columns = new List<JQGridColumn>() { new JQGridColumn { DataField = "OrderID", Width = 50 }, new JQGridColumn { DataField = "OrderDate", Width = 100, DataFormatString = "{0:d}" }, new JQGridColumn { DataField = "CustomerID", Width = 100 }, new JQGridColumn { DataField = "Freight", Width = 75 }, new JQGridColumn { DataField = "ShipName" } }, Width = Unit.Pixel(640) }; OrdersGrid.ToolBarSettings.ShowRefreshButton = true; } public JQGrid OrdersGrid { get; set; } } } and in the view I am caling like this <div> <%= Html.Trirand().JQGrid(Model.OrdersGrid, "JQGrid1") %> </div> I am getting result perfect.. but for column Freight in the Jquery grid I need to place a dropdown list dynamically for all result rows.. can anyone help me out.. THanks

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  • Good data structure for efficient insert/querying on arbitrary properties

    - by Juliet
    I'm working on a project where Arrays are the default data structure for everything, and every query is a linear search in the form of: Need a customer with a particular name? customer.Find(x => x.Name == name) Need a customer with a particular unique id? customer.Find(x => x.Id == id) Need a customer of a particular type and age? customer.Find(x => x is PreferredCustomer && x.Age >= age) Need a customer of a particular name and age? customer.Find(x => x.Name == name && x.Age == age) In almost all instances, the criteria for lookups is well-defined. For example, we only search for customers by one or more of the properties Id, Type, Name, or Age. We rarely search by anything else. Is a good data structure to support arbitrary queries of these types with lookup better than O(n)? Any out-of-the-box implementations for .NET?

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  • EXC_BAD_ACCESS on button press for button dynamically added to UIView within UIScrollView

    - by alan
    OK. It's an iPad app. Within the DetailViewController I have added a UIScrollView through IB and within that UIScrollView I have added a UIView (also added through IB) which holds various dynamically added UITableViews, UILabels and UIButtons. My problem is that I'm getting errors on the UIButton clicks. I have defined this method: - (void)translationSearch:(id)sender { NSLog(@"in transearch"); [self doSearch]; } This is how I'm adding the UIButton to the UIView: UIButton *translationButton = [UIButton buttonWithType:UIButtonTypeRoundedRect]; translationButton.frame = CGRectMake(6, 200, 200, 20); translationButton.backgroundColor = [UIColor clearColor]; [translationButton setTitle:@"testing" forState:UIControlStateNormal]; [translationButton addTarget:self action:@selector(translationSearch:) forControlEvents:UIControlEventTouchUpInside]; [verbView addSubview:translationButton]; Now the button is added to the form without any issue but, when I press it, I am getting an EXC_BAD_ACCESS error. I'm sure it's staring me in the face but I've passed my usual time limit for getting a bug like this fixed so any help would be greatly appreciated. The only thing I can think is the fact that the UIButton is within a UIView which is within a UIScrollView which is within the view controller is somehow causing an issue. Cheers.

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  • How do I use an array as an object attribute in Perl?

    - by superstar
    Hello guys, I need some help regarding the arrays in Perl This is the constructor i have. sub new { my $class = shift; my @includeobjects = (); my @excludeobjects = (); my $Packet = { _PacketName => shift, _Platform => shift, _Version => shift, @_IncludePath => @includeobjects, }; bless $Packet, $class; return $Packet; } sub SetPacketName { my ( $Packet, $PacketName ) = @_; $Packet->{_PacketName} = $PacketName if defined($PacketName); return $Packet->{_PacketName}; } sub SetIncludePath { my ( $Packet, @IncludePath ) = @_; $Packet->{@_IncludePath} = @IncludePath; return $Packet->{@_IncludePath}; } sub GetPacketName { my( $Packet ) = @_; return $Packet->{_PacketName}; } sub GetIncludePath { my( $Packet ) = @_; return $Packet->{@_IncludePath}; } The get and set methods work fine for PacketName. But since IncludePath is an array, I could not get it work. The declaration is what I am not able to get right.

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  • Behavior of local variables in JavaScripts with()-statement

    - by thr
    I noticed some weird (and to my knowledge undefined behavior, by the ECMA 3.0 Spec at least), take the following snippet: var foo = { bar: "1", baz: "2" }; alert(bar); with(foo) { alert(bar); alert(bar); } alert(bar); It crashes in both Firefox and Chrome, because "bar" doesn't exist in the first alert(); statement, this is as expected. But if you add a declaration of bar inside the with()-statement, so it looks like this: var foo = { bar: "1", baz: "2" }; alert(bar); with(foo) { alert(bar); var bar = "g2"; alert(bar); } alert(bar); It will produce the following: undefined, 1, g2, undefined It seems as if you create a variable inside a with()-statement most browsers (tested on Chrome or Firefox) will make that variable exist outside that scope also, it's just set to undefined. Now from my perspective bar should only exist inside the with()-statement, and if you make the example even weirder: var foo = { bar: "1", baz: "2" }; var zoo; alert(bar); with(foo) { alert(bar); var bar = "g2"; zoo = function() { return bar; } alert(bar); } alert(bar); alert(zoo()); It will produce this: undefined, 1, g2, undefined, g2 So the bar inside the with()-statement does not exist outside of it, yet the runtime somehow "automagically" creates a variable named bar that is undefined in its top level scope (global or function) but this variable does not refer to the same one as inside the with()-statement, and that variable will only exist if a with()-statement has a variable named bar that is defined inside it. Very weird, and inconsistent. Anyone have an explanation for this behavior? There is nothing in the ECMA Spec about this.

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  • Continuing JavaScript "classes" - enums within

    - by espais
    From a previous question, I have the following: So I have implemented a resource class, now I'd like to continue extending it and add all my constants and enums (or as far as JS will allow...). This is what I currently have: var resources = { // images player : new c_resource("res/player.png"), enemies : new c_resource("res/enemies.png"), tilemap : new c_resource("res/tilemap.png") }; And this is what I would like to continue to extend it to: var resources = { // images player : new c_resource("res/player.png"), enemies : new c_resource("res/enemies.png"), tilemap : new c_resource("res/tilemap.png"), // enums directions : {up:0, right:1, down:2, left:3}, speeds : {slow: 1, medium: 3, fast: 5} }; ... function enemies() { this.dir = resources.directions.down; // initialize to down } When I attempt to access resources.directions.up, my JS script goes down in a flaming pile of burning code. Are enums allowed in this context, and if not, how can I properly insert them to be used outside of a normal function? I have also tried defining them as global to a similar effect. edits: fixed the comma...that was just an error in transcribing it. When I run it in Firefox and watch the console, I get an error that says resources is undefined. The resources 'class' is defined at the top of my script, and function enemies() directly follows...so from what I understand it should still be in scope...

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