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  • Custom dropdown for CComboBox

    - by WalderFrey
    I'm trying to create a custom dropdown for a derivative of CComboBox. The dropdown will be a calendar control plus some 'hotspots', e.g. So I figure the best way to achieve this is to have a simple CWnd-derived class which acts as the parent to the calendar control, and have it paint the hotspots itself. The window needs to be a popup window - I think - rather than a child window so that it isn't clipped. But doing this causes the dialog (on which the combobox control is placed) to stop being the topmost (foreground?) window, leading to its frame being drawn differently: This spoils the illusion that the dropdown is part of the combobox since its acting more like a modal dialog at this point. Any suggestions on how I make the custom dropdown behave like the regular dropdown? Are there any other pitfalls I need to watch out for, e.g. focus and mouse capture issues?

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  • How does jQuery .data() work?

    - by kazanaki
    My Javascript knowledge is pretty limited. Instead of asking several javascript questions I got the "message" from Stack overflow and started using jQuery right away in order to save me some time. However several times I do not undestand the "magic" behind jQuery and I would love to learn the details. I want to use .data() in my application. The examples are very helpful. I do not understand however WHERE these values are stored. I inspect the webpage with Firebug and as soon as .data() saves an object to a dom element, I do not see any change in Firebug (either HTML or Dom tabs). I tried to look at jQuery source, but it is very advanced for my Javascript knowledge and I lost myself. So the question is: Where do the values stored by jQuery.data() actually go? Can I inspect/locate/list/debug them using a tool?

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  • Why is my GUI unresponsive while a SwingWorker thread runs?

    - by Starchy
    Hello, I have a SwingWorker thread with an IOBound task which is totally locking up the interface while it runs. Swapping out the normal workload for a counter loop has the same result. The SwingWorker looks basically like this: public class BackupWorker extends SwingWorker<String, String> { private static String uname = null; private static String pass = null; private static String filename = null; static String status = null; BackupWorker (String uname, String pass, String filename) { this.uname = uname; this.pass = pass; this.filename = filename; } @Override protected String doInBackground() throws Exception { BackupObject bak = newBackupObject(uname,pass,filename); return "Done!"; } } The code that kicks it off lives in a class that extends JFrame: public void actionPerformed(ActionEvent event) { String cmd = event.getActionCommand(); if (BACKUP.equals(cmd)) { SwingUtilities.invokeLater(new Runnable() { public void run() { final StatusFrame statusFrame = new StatusFrame(); statusFrame.setVisible(true); SwingUtilities.invokeLater(new Runnable() { public void run () { statusFrame.beginBackup(uname,pass,filename); } }); } }); } } Here's the interesting part of StatusFrame: public void beginBackup(final String uname, final String pass, final String filename) { worker = new BackupWorker(uname, pass, filename); worker.execute(); try { System.out.println(worker.get()); } catch (InterruptedException e) { e.printStackTrace(); } catch (ExecutionException e) { e.printStackTrace(); } } } So far as I can see, everything "long-running" is handled by the worker, and everything that touches the GUI on the EDT. Have I tangled things up somewhere, or am I expecting too much of SwingWorker?

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  • Should I add try/catch around when casting on an attribute of JSP implicit object?

    - by Michael Mao
    Hi all: Basically what I mean is like this: List<String[]> routes = (List<String[]>)application.getAttribute("routes"); For the above code, it tries to get an attribute named "routes" from the JSP implicit object - application. But as everyone knows, after this line of code, routes may very well contains a null - which means this application hasn't got an attribute named "routes". Is this "casting on null" good programming practice in Java or not? Basically I try to avoid exceptions such as java.io.InvalidCastException I reckon things like this are more as "heritage" of Java 1.4 when generic types were not introduced to this language. So I guess everything stored in application attributes as Objects (Similar to traditional ArrayList). And when you do "downcast", there might be invalid casts. What would you do in this case? Update: Just found that although in the implicit object application I did store a List of String arrays, when I do this : List<double[]> routes = (List<double[]>)application.getAttribute("routes"); It doesn't produce any error... And I felt not comfortable already... And even with this code: out.print(routes.get(0)); It does print out something strange : [Ljava.lang.String;@18b352f Am I printing a "pointer to String"? I can finally get an exception like this: out.print(routes.get(0)[1]); with error : java.lang.ClassCastException: [Ljava.lang.String; Because it was me to add the application attribute, I know which type should it be cast to. I feel this is not "good enough", what if I forget the exact type? I know there are still some cases where this sort of thing would happen, such as in JSP/Servlet when you do casting on session attributes. Is there a better way to do this? Before you say:"OMG, why you don't use Servlets???", I should justify my reason as this: - because my uni sucks, its server can only work with Servlets generated by JSP, and I don't really want to learn how to fix issues like that. look at my previous question on this , and this is uni homework, so I've got no other choice, forget all about war, WEB-INF,etc, but "code everything directly into JSP" - because the professors do that too. :)

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  • control + enter in browser takes only .com?

    - by Abhilash M
    I have this strange problem, how exactly does control + enter decides the domain of a website?? If i type stackoverflow,then hit control+enter, it works and takes to homepage, but i type ubuntuforums, then hit control + enter, it does not recognise its ubuntuforums.org, but goes to ubuntuforums.com?? How does this exactly work? If i need to change this behaviour, how should i do it?

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  • Haskell Ord instance with a Set

    - by mvid
    I have some code that I would like to use to append an edge to a Node data structure: import Data.Set (Set) import qualified Data.Set as Set data Node = Vertex String (Set Node) deriving Show addEdge :: Node -> Node -> Node addEdge (Vertex name neighbors) destination | Set.null neighbors = Vertex name (Set.singleton destination) | otherwise = Vertex name (Set.insert destination neighbors) However when I try to compile I get this error: No instance for (Ord Node) arising from a use of `Set.insert' As far as I can tell, Set.insert expects nothing but a value and a set to insert it into. What is this Ord?

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  • python: can't terminate a thread hung in socket.recvfrom() call

    - by Dihlofos
    Hello, everyone I cannot get a way to terminate a thread that is hung in a socket.recvfrom() call. For example, ctrl+c that should trigger KeyboardInterrupt exception can't be caught. Here is a script I've used for testing: from socket import * from threading import Thread from sys import exit class TestThread(Thread): def __init__(self,host="localhost",port=9999): self.sock = socket(AF_INET,SOCK_DGRAM) self.sock.bind((host,port)) super(TestThread,self).__init__() def run(self): while True: try: recv_data,addr = self.sock.recvfrom(1024) except (KeyboardInterrupt, SystemExit): sys.exit() if __name__ == "__main__": server_thread = TestThread() server_thread.start() while True: pass The main thread (the one that executes infinite loop) exits. However the thread that I explicitly create, keeps hanging in recvfrom(). Please, help me resolve this.

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  • How to replace empty string with zero in comma-separated string?

    - by dsaccount1
    "8,5,,1,4,7,,,,7,,1,9,3,6,,,8,6,3,9,,2,5,4,,,,,3,2,,,7,4,1,1,,4,,6,9,,5,,,,5,,,1,,6,3,,,6,5,,,,7,4,,1,7,6,,,,8,,5,,,7,1,,3,9," I'm doing a programming challenge where i need to parse this sequence into my sudoku script. Need to get the above sequence into 8,5,0,1,4,7,0,0,0,7,0,1,9,3,6,0,0,8......... I tried re but without success, help is appreciated, thanks.

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  • iPhone: Error when using -(id)initWithNibName

    - by Nic Hubbard
    I am trying to use the following code, but I always get an error that I can find little information about: - (id)initWithNibName:@"MyRidesListView" bundle:nil { if ((self = [super initWithNibName:@"MyRidesListView" bundle:nil])) { // Custom initialization } return self; } Error: expected identifier before 'OBJC_STRING' token This seems like a simple method to be calling. This is for a UINavigationController. Ideas?

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  • Unpacking tuple types in Scala

    - by jpalecek
    I was just wondering, can I decompose a tuple type into its components' types in Scala? I mean, something like this trait Container { type Element } trait AssociativeContainer extends Container { type Element <: (Unit, Unit) def get(x : Element#First) : Element#Second }

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  • Learning Haskell maps, folds, loops and recursion

    - by Darknight
    I've only just dipped my toe in the world of Haskell as part of my journey of programming enlightenment (moving on from, procedural to OOP to concurrent to now functional). I've been trying an online Haskell Evaluator. However I'm now stuck on a problem: Create a simple function that gives the total sum of an array of numbers. In a procedural language this for me is easy enough (using recursion) (c#) : private int sum(ArrayList x, int i) { if (!(x.Count < i + 1)) { int t = 0; t = x.Item(i); t = sum(x, i + 1) + t; return t; } } All very fine however my failed attempt at Haskell was thus: let sum x = x+sum in map sum [1..10] this resulted in the following error (from that above mentioned website): Occurs check: cannot construct the infinite type: a = a -> t Please bear in mind I've only used Haskell for the last 30 minutes! I'm not looking simply for an answer but a more explanation of it. Thanks in advanced.

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  • Small Python optional arguments question

    - by ooboo
    I have two functions: def f(a,b,c=g(b)): blabla def g(n): blabla c is an optional argument in function f. If the user does not specify its value, the program should compute g(b) and that would be the value of c. But the code does not compile - it says name 'b' is not defined. How to fix that? Someone suggested: def g(b): blabla def f(a,b,c=None): if c is None: c = g(b) blabla But this doesn't work, because maybe the user intended c to be None and then c will have another value.

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  • Using Python to get a CSV output for the following example.

    - by Az
    Hi there, I'm back again with my ongoing saga of Student-Project Allocation questions. Thanks to Moron (who does not match his namesake) I've got a bit of direction for an evaluation portion of my project. Going with the idea of the Assignment Problem and Hungarian Algorithm I would like to express my data in the form of a .csv file which would end up looking like this in spreadsheet form. This is based on the structure I saw here. | | Project 1 | Project 2 | Project 3 | |----------|-----------|-----------|-----------| |Student1 | | 2 | 1 | |----------|-----------|-----------|-----------| |Student2 | 1 | 2 | 3 | |----------|-----------|-----------|-----------| |Student3 | 1 | 3 | 2 | |----------|-----------|-----------|-----------| To make it less cryptic: the rows are the Students/Agents and the columns represent Projects/Task. Obviously ONE project can be assigned to ONE student. That, in short, is what my project is about. The fields represent the preference weights the students have placed upon the projects (ranging from 1 to 10). If blank, that student does not want that project and there's no chance of him/her being assigned such. Anyway, my data is stored within dictionaries. Specifically the students and projects dictionaries such that: students[student_id] = Student(student_id, student_name, alloc_proj, alloc_proj_rank, preferences) where preferences is in the form of a dictionary such that preferences[rank] = {project_id} and projects[project_id] = Project(project_id, project_name) I'm aware that sorted(students.keys()) will give me a sorted list of all the student IDs which will populate the row labels and sorted(projects.keys()) will give me the list I need to populate the column labels. Thus for each student, I'd go into their preferences dictionary and match the applicable projects to ranks. I can do that much. Where I'm failing is understanding how to create a .csv file. Any help, pointers or good tutorials will be highly appreciated.

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  • Global and local variables in my script

    - by Acorn
    I'm starting out learning javascript, and tried to write a little script that would make a grid of divs on a page. Here's the script: var tileWidth=50; var tileHeight=100; var leftPos=10; var topPos=10; var columns=10; var rows=10; var spacing=5; $('document').ready(function() { placeTiles(); }); function makeRow() { for (var i=0; i<columns; i++) { $('#canvas').append('<div class="tile" style="left:' + leftPos + 'px;top:' + topPos + 'px;"></div>'); var leftPos = leftPos + tileWidth + spacing; } } function placeTiles() { for (var i=0; i<rows; i++) { makeRow(); var topPos = topPos + tileHeight + spacing; } } At the moment, 100 <div>s get created, all with a top position of 10px and a left position of undefined (for the first <div> in the row) or NaN. What should I be doing differently? Why can't makerow() see my global leftPos variable (and all the other variables for that matter)? Thanks.

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  • Help me decipher this output

    - by Bragaadeesh
    Hi, I have started learning Ruby recently and I was trying out the following piece of code. a=[1,2] b='slam dunk' a.each { |b| c=a*b; puts c;} I am getting the following output. I have no clue why. I expected an error or something to be thrown. Can someone explain me why this happens? 1 2 1 2 1 2 Thanks

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  • split twice in the same expression?

    - by UcanDoIt
    Imagine I have the following: inFile = "/adda/adas/sdas/hello.txt" # that instruction give me hello.txt Name = inFile.name.split("/") [-1] # that one give me the name I want - just hello Name1 = Name.split(".") [0] Is there any chance to simplify that doing the same job in just one expression?

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  • How to echo Hyperlink Containing a Variable?

    - by John
    Hello, In the code below, I would like to make the word that prints out as the variable "$submittor" a hyperlink to "http://www...com/.../members/index.php?profile=$submittor" . I can't get it to work; I think I'm doing the formatting wrong. How can I do it? Thanks in advance, John echo '<div class="sitename3name">Submitted by '.$submittor.' on '.$dt->format('F j, Y &\nb\sp &\nb\sp g:i a').'</div>';

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  • LaTex: how does the include-command work?

    - by HH
    I supposed the include-command copy-pastes code in the compilation, it is wrong because the code stopped working. Please, see the middle part in the code. I only copy-pasted the code to the file and added the include-command. $ cat results/frames.tex 10.31 & 8.50 & 7.40 \\ 10.34 & 8.53 & 7.81 \\ 8.22 & 8.62 & 7.78 \\ 10.16 & 8.53 & 7.44 \\ 10.41 & 8.38 & 7.63 \\ 10.38 & 8.57 & 8.03 \\ 10.13 & 8.66 & 7.41 \\ 8.50 & 8.60 & 7.15 \\ 10.41 & 8.63 & 7.21 \\ 8.53 & 8.53 & 7.12 \\ Latex code \begin{table} \begin{tabular}{ | l | m | r |} \hline $t$ / s & $d_{1}$ / s & $d_{2}$ / s \\ $\Delta h = 0,01 s$ & $\Delta d = 0,01 s$ & $\Delta d = 0,01 s$ \\ \hline % I JUST COPIED THE CODE from here to the file, included. % It stopped working, why? \include{results/frames.tex} \hline $\pi (\frac{d_{1}}{2} - \frac{d_{2}}{2})$ & $2 \pi R h$ & $2 \pi r h$ \\ \hline \end{tabular} \end{table}

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  • Step by step help and guidance

    - by ChrisC
    Is there such a thing as a paid (or free would be GREAT, but unlikely I'm thinking) resource that could help a newbie with guidance and help as I create my first app (C# with SQLite db)? Stackoverflow is great, but a one-on-one person who was familiar with exactly what I'm doing would be even better.

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  • mod_rewrite RewriteRule is not working

    - by buggy1985
    Hi, This is a follow-up of this question: Rewrite URL - how to get the hostname and the path? I got this Rewrite Rule: RewriteEngine On RewriteRule ^(http://[-A-Za-z0-9+&@#/%=~_|!:,.;]*)/([-A-Za-z0-9+&@#/%=~_|!:,.;]*)\?([A-Za-z0-9+&@#/%=~_|!:,.;]*)$ http://http://www.xmldomain.com/bla/$2?$3&rtype=xslt&xsl=$1/$2.xsl it seems to be correct, and exactly what I need. But it doesn't work on my server. I get a 404 page not found error. mod_rewrite is enabled, as the following simple rule is working fine: RewriteEngine On RewriteRule ^page/([^/\.]+)/?$ index.php?page=$1 [L] Can you help? Thanks

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