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  • How to place images on top of each other in java

    - by Haxed
    Hi, I have a background image of a road, which I have displayed on a JFrame using an ImageIcon. I want to put a car on top of that background image at a certain (x,y) location. I tried using another ImageIcon and the background does not appear when I run the program , however the car does. import javax.swing.ImageIcon; import javax.swing.JFrame; import javax.swing.JLabel; public class Gui extends JFrame { private ImageIcon northcar = new ImageIcon("src/north.gif"); private ImageIcon usIcon = new ImageIcon("src/trafficLight.jpg"); public Gui() { add(new JLabel(usIcon)); // background image does not appear after the i added the northcar label add(new JLabel(northcar)); // this picture can be seen } public static void main(String[] args) { Gui frame = new Gui(); frame.setTitle("TestImageIcon"); frame.setLocationRelativeTo(null); // Center the frame frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setBounds(0, 0, 650, 650); frame.setVisible(true); } } I heard about using a canvas but have no clue. Any ideas ? Many Thanks

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  • How to specify allowed exceptions in WCF's configuration file?

    - by tucaz
    Hello! I´m building a set of WCF services for internal use through all our applications. For exception handling I created a default fault class so I can return treated message to the caller if its the case or a generic one when I have no clue what happened. Fault contract: [DataContract(Name = "DefaultFault", Namespace = "http://fnac.com.br/api/2010/03")] public class DefaultFault { public DefaultFault(DefaultFaultItem[] items) { if (items == null || items.Length== 0) { throw new ArgumentNullException("items"); } StringBuilder sbItems = new StringBuilder(); for (int i = 0; i Specifying that my method can throw this exception so the consuming client will be aware of it: [OperationContract(Name = "PlaceOrder")] [FaultContract(typeof(DefaultFault))] [WebInvoke(UriTemplate = "/orders", BodyStyle = WebMessageBodyStyle.Bare, ResponseFormat = WebMessageFormat.Json, RequestFormat = WebMessageFormat.Json, Method = "POST")] string PlaceOrder(Order newOrder); Most of time we will use just .NET to .NET communication with usual binds and everything works fine since we are talking the same language. However, as you can see in the service contract declaration I have a WebInvoke attribute (and a webHttp binding) in order to be able to also talk JSON since one of our apps will be built for iPhone and this guy will talk JSON. My problem is that whenever I throw a FaultException and have includeExceptionDetails="false" in the config file the calling client will get a generic HTTP error instead of my custom message. I understand that this is the correct behavior when includeExceptionDetails is turned off, but I think I saw some configuration a long time ago to allow some exceptions/faults to pass through the service boundaries. Is there such thing like this? If not, what do u suggest for my case? Thanks a LOT!

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  • How can I render an in-memory UIViewController's view Landscape?

    - by Aaron
    I'm trying to render an in-memory (but not in hierarchy, yet) UIViewController's view into an in-memory image buffer so I can do some interesting transition animations. However, when I render the UIViewController's view into that buffer, it is always rendering as though the controller is in Portrait orientation, no matter the orientation of the rest of the app. How do I clue this controller in? My code in RootViewController looks like this: MyUIViewController* controller = [[MyUIViewController alloc] init]; int width = self.view.frame.size.width; int height = self.view.frame.size.height; int bitmapBytesPerRow = width * 4; unsigned char *offscreenData = calloc(bitmapBytesPerRow * height, sizeof(unsigned char)); CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef offscreenContext = CGBitmapContextCreate(offscreenData, width, height, 8, bitmapBytesPerRow, colorSpace, kCGImageAlphaPremultipliedLast); CGContextTranslateCTM(offscreenContext, 0.0f, height); CGContextScaleCTM(offscreenContext, 1.0f, -1.0f); [(CALayer*)[controller.view layer] renderInContext:offscreenContext]; At that point, the offscreen memory buffers contents are portrait-oriented, even when the window is in landscape orientation. Ideas?

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  • How to update GUI thread/class from worker thread/class?

    - by user315182
    First question here so hello everyone. The requirement I'm working on is a small test application that communicates with an external device over a serial port. The communication can take a long time, and the device can return all sorts of errors. The device is nicely abstracted in its own class that the GUI thread starts to run in its own thread and has the usual open/close/read data/write data basic functions. The GUI is also pretty simple - choose COM port, open, close, show data read or errors from device, allow modification and write back etc. The question is simply how to update the GUI from the device class? There are several distinct types of data the device deals with so I need a relatively generic bridge between the GUI form/thread class and the working device class/thread. In the GUI to device direction everything works fine with [Begin]Invoke calls for open/close/read/write etc. on various GUI generated events. I've read the thread here (How to update GUI from another thread in C#?) where the assumption is made that the GUI and worker thread are in the same class. Google searches throw up how to create a delegate or how to create the classic background worker but that's not at all what I need, although they may be part of the solution. So, is there a simple but generic structure that can be used? My level of C# is moderate and I've been programming all my working life, given a clue I'll figure it out (and post back)... Thanks in advance for any help.

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  • ASP.NET MVC 2 user input to SQL 2008 Database problems

    - by Rob
    After my publish in VS2010 the entire website loads and pulls data from the database perfectly. I can even create new users through the site with the correct key code, given out to who needs access. I have two connection strings in my web.config file The first: <add xdt:Transform="SetAttributes" xdt:Locator="Match(name)" name="EveModelContainer" connectionString="metadata=res://*/Models.EdmModel.EveModel.csdl|res://*/Models.EdmModel.EveModel.ssdl|res://*/Models.EdmModel.EveModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=localhost;Initial Catalog=fleet;Persist Security Info=True;User ID=fleet;Password=****&quot;" providerName="System.Data.EntityClient" /> The second: <add xdt:Transform="SetAttributes" xdt:Locator="Match(name)" name="ApplicationServices" connectionString="Data Source=localhost;Initial Catalog=fleet;Persist Security Info=True;User ID=fleet;Password=****;MultipleActiveResultSets=True" /> The first one is the one that is needed to post data with the main application, EveModelContainer. Everything else is pulled using the standard ApplicationServices connection. Do you see anything wrong with my connectionstring? I'm at a complete loss here. The site works perfectly on my friends server and not on mine... Could it be a provider issue? And if I go to iis 7's manager console, and click .net users I get a pop up message saying the custom provider isn't a trusted provider do I want to allow it to run at a higher trust level. I'm at the point where I think its either my string or this trusted provider error... but I have no clue how to add to the trusted provider list... Thank you in advance!!!

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  • WebView and HTML5 <video>

    - by brian moore
    I'm piecing together a cheapo app that amongst other things "frames" some of our websites... Pretty simple with the WebViewClient... until I hit the video. The video is done as HTML5 elements, and these work fine and dandy on Chrome, iPhones, and now that we fixed the encoding issues it works great on Android... in the native browser. Now the rub: WebView doesn't like it. At all. I can click on the poster image, and nothing happens. Googling, I found http://www.codelark.com/2010/05/12/android-viewing-video-from-embedded-webview/ which is close, but seems to be based on a 'link' (as in a href...) instead of a video element. (onDownloadListener does not appear to get invoked on video elements...) I also see references to overriding onShowCustomView, but that seems to not get called on video elements... nor does shouldOverrideUrlLoading.. I would rather not get into "pull xml from the server, reformat it in the app".. by keeping the story layout on the server, I can control the content a bit better without forcing people to keep updating an app. So if I can convince WebView to handle tags like the native browser, that would be best. I'm clearly missing something obvious.. but I have no clue what.

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  • My ifelse statement's result depends on the actions for true/false?

    - by Antal
    Currently I am building a route for a truck to drive inside my netlogo-land. When the truck is next to the shop-patch where it should deliver, the truck needs to change its actions. However my if or ifelse statement does not seem to respond well and the answer depends on the output. With some tests: turtles ifelse ((patch (first dirx) (first diry)) = one-of neighbors4) [write "11"] [write "22"] "11" turtles ifelse ((patch (first dirx) (first diry)) = one-of neighbors4) [write "111"] [write "122"] "122" turtles ifelse (patch (first dirx) (first diry)) = one-of neighbors4 [write "111"] [write "122"] "122" turtles ifelse (patch (first dirx) (first diry)) = one-of neighbors4 [write "11"] [write "12"] "12" turtles ifelse (patch (first dirx) (first diry)) = one-of neighbors4 [write "11"] [write "22"] "11" Please note that during this time I do not move my truck, I use the command center to ask these questions (from turtle truck perspective). I am very confused about this. As the only thing I change is the action (what to write). This should not impact the true/false statement itself. Does anybody have any clue what is going on here and why the ifelse responds strange?

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  • Where is the errnos defined? Example linux c/c++ program for i2c.

    - by Johan
    Hi When something goes wrong in a classic linux c/c++ software we have the magic variable errno that gives us a clue on what just went wrong. But where is those errors defined? Let's take a example (it's actually a piece from a Qt app, therefore the qDebug()). if (ioctl(file, I2C_SLAVE, address) < 0) { int err = errno; qDebug() << __FILE__ << __FUNCTION__ << __LINE__ << "Can't set address:" << address << "Errno:" << err << strerror(err); .... The next step is to look at what that errno was so we can decide if we just quit or try to do something about the problem. So we maybe add a if or switch at this point. if (err == 9) { // do something... } else { //do someting else } And my question is where to find the errors that "9" represents? I don't like that kind of magic numbers in my code. /Thanks

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  • Why do I get a Illegal Access Error when running my Android tests?

    - by Janusz
    I get the following stack trace when running my Android tests on the Emulator: java.lang.NoClassDefFoundError: client.HttpHelper at client.Helper.<init>(Helper.java:14) at test.Tests.setUp(Tests.java:15) at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:164) at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:151) at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:425) at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1520) Caused by: java.lang.IllegalAccessError: cross-loader access from pre-verified class at dalvik.system.DexFile.defineClass(Native Method) at dalvik.system.DexFile.loadClass(DexFile.java:193) at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:203) at java.lang.ClassLoader.loadClass(ClassLoader.java:573) at java.lang.ClassLoader.loadClass(ClassLoader.java:532) ... 11 more I run my tests from an extra project. And it seems there are some problems with loading the classes from the other project. I have run the tests before but now they are failing. The project under tests runs without problems. Line 14 of the Helper Class is: this.httpHelper = new HttpHelper(userProfile); I start a HttpHelper class that is responsible for executing httpqueries. I think somehow this helper class is not available anymore, but I have no clue why.

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  • PDFBox: Problem with converting pdf page into image

    - by user552910
    My mission is pretty simple: converting every single page of a pdf file into images. I tried using icepdf open source version to generate the images but they don't generate the image with the correct font. So I start using PDFBox instead. The code is the following: PDDocument document = PDDocument.load(new File("testing.pdf")); List<PDPage> pages = document.getDocumentCatalog().getAllPages(); for (int i = 0; i < pages.size(); i++) { PDPage singlePage = pages.get(i); BufferedImage buffImage = convertToImage(singlePage, 8, 12); ImageIO.write(buffImage, "png", new File(PdfUtil.DATA_OUTPUT_DIR+(count++)+".png")); } The font looks good, but the pictures within the pdf file look fainted out (See the attachment). I look into the source code but I still have no clue how to fix it. Do you guys have any idea what's going on? Please help. Thanks!!

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  • Doctrine 2 entity cannot be saved with its many-to-many related entities

    - by user1333185
    I'm writing a project in ZF and have many-to-many related accounts and videos entities and I provide the account with the videos collection. When I try to save the account I receive the following error: A new entity was found through the relationship 'Entities\Account#playlistVideos' that was not configured to cascade persist operations for entity: Entities\Video@000000004d5f02ef00000000196757dc. Explicitly persist the new entity or configure cascading persist operations on the relationship. If you cannot find out which entity causes the problem implement 'Entities\Video#__toString()' to get a clue. I found a suggested solution with cascade={"persist"} which should allow videos to be saved together with the account by only specifying $this-em-persist($account) but then I get the error: Fatal error: method_exists(): The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition "Proxies\EntitiesAccountProxy" of the object you are trying to operate on was loaded before unserialize() gets called or provide a __autoload() function to load the class definition in... The same happens when I try to manually persist videos and account. Thank you for the help in advance.

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  • Strange Bug in iPhone SDK

    - by Crazer
    Hi all, I found a strange bug in iphone sdk. I try to explain it: I have a number of uibuttons in a view. They are all just images. Every buttons has a title but that is not displayed so you just see the images (all 80x80). I made it all in IB. In my code I position those buttons. Here's a snippet of that code: for(NSString *iconObject in iconArray){ //retrieve UIButtons from dictionary iconButton = [allIconsDictionary objectForKey:iconObject]; iconButton.hidden = NO; //position and resize icon Buttons iconButton.frame = CGRectMake((79 * col) + 28, (70 * row) + 70, 80 ,80); col++; //five buttons in a row if(col%5 == 0){ row++; col = 0; } } That works like it should. But for all buttons that title starts with a 't' the title displays in the simulator (also on the device). The title of the other buttons are not shown just those where the title starts with a 't'. I have no clue what this could be?! I hope I could describe the problem.

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  • rehabilitating a button

    - by Michele Petraroli
    if($('.click').one('click')){ $('.click').click(function(){ $('.mainContent').animate( {"height":"+=620px"}, 800, 'easeInBack'); $('.eneButton').animate( { "top":"+=310px"}, 1500, 'easeInOutExpo'); $('.eneButton').animate( {"left":"-=310px"}, 1500, 'easeInOutExpo') $('.giardButton').animate( {"top":"+=620px"}, 2000, 'easeInOutExpo') $('.giardButton').animate( {"left":"-=620px"}, 2000, 'easeInOutExpo'); $('.click').off('click'); }) } if ($('.close').one('click')){ $('.close').click(function(){ $('.content, .sec').fadeOut(250); $('.eneButton').animate( {"left":"+=310px"}, 1500, 'easeInOutExpo') $('.eneButton').animate( { "top":"-=310px"}, 1500, 'easeInOutExpo'); $('.giardButton').animate( {"left":"+=620px"}, 2000, 'easeInOutExpo'); $('.giardButton').animate( {"top":"-=620px"}, 2000, 'easeInOutExpo'); $('.mainContent').animate( {"height":"-=620px"}, 3500, 'easeInBack'); $('.click').on('click'); }) } the animation is working fine in both ways but I need that users may restart the animation again when its closed. as you can see from the code you do one click and an animation starts, then you select a list of categories which you can close with a click on a "X" like in windows, when you do that the animation start again till all look like as the begin. Now if I click again on it the animation doesnt start no more. any clue?

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  • em1: watchdog timeout -- resetting virtualbox

    - by lightmanhk
    everyone. I try to configure network adapter of my freebsd on virtualbox machine. At first setting up, I got it right. However, after a couple of reboots, my VM gives me a error message: says "em1:Watchdog timeout -- resetting" I tried to google it, and there is no solution that works for me. The following is my network adapter of my VM: Apapter1: NAT Adapter2: Host-only Adapter vboxnet0 On my Virtualbox setting: Host-only networks: Adapter: IPv4 address: 192.168.56.10 IPv4 network mask: 255.255.255.0 On my FreeBSD VM /etc/rc.conf ifconfig_em0="DHCP" ifconfig_em1="inet 192.168.56.11 netmask 255.255.255.0" Moreover, strange thing is that, for example, if timeout error message show at ttyv0 , when I log in at different ttyv[1-9], the error message will not be shown. but in ttyv0, it still gives me the message. And, in term of functionality of em1, it does work. I have no clue about this problem. Hoping any one can give me a solution or suggestion. That will be great! Thanks a lot. Freebsd version: 9.0-RELEASE FreeBSD 9.0-RELEASE i386 Virtual box: 4.1.2 r73507

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  • How to Parse an XML (using XELement) having multiple Namespace ?

    - by Subhen
    Hi I , I get the followinng Xresponse after parsing the XML document: <DIDL-Lite xmlns="urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:upnp="urn:schemas-upnp-org:metadata-1-0/upnp/" xmlns:dlna="urn:schemas-dlna-org:metadata-1-0/"> <item id="1182" parentID="40" restricted="1"> <title>Hot Issue</title> </item> As per the earlier thread, When there is a default namespace in the document, you must parse it as if it were a named namespace. For example. XNamespace ns = "urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/"; var xDIDL = xResponse.Element(ns + "DIDL-Lite"); But in my case I have four different name space. I am not getting any results after using the following query , I am getting the response , Not Yeilding any results: XNamespace dc = "http://purl.org/dc/elements/1.1/"; var vAudioData = from xAudioinfo in xResponse.Descendants(ns + "DIDL-lite").Elements("item") select new RMSMedia { strAudioTitle = ((string)xAudioinfo.Element(dc + "title")).Trim(), }; I have no clue whats going on as am new to it. Please help

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  • error C2146: syntax error : missing ';' before identifier 'g_App'

    - by numerical25
    I wish c++, was a little more specific on the messages they give. The following error is being thrown in the document below main.h #ifndef main_h #define main_h //includes #include <windows.h> #include <commctrl.h> #include <d3d9.h> #include <fstream> #include "capplication.h" //constants #define TITLE "D3D Tut 01: Create Window" #define WINDOW_X 350 #define WINDOW_Y 320 //Button ID's #define ID_START 1 #define ID_CANCEL 2 //globals extern CApplication g_App; //function prototypes LRESULT CALLBACK WindowProcedure(HWND,UINT,WPARAM,LPARAM); #endif The only header file that could possible throw this error is the capplication.h. given below capplication.h #ifndef capplication_h #define capplication_h #include"main.h" class CApplication { public: CApplication(void); ~CApplication(void); void InitWindow(void); void SaveSettings(void); void LoadSettings(void); void KillWindow(void); inline bool GetWindowStatus(void) { return m_bRunningWindow; } inline HWND GetWindowHandle(void) { return m_hWindow; } inline void SetWindowStatus(bool bRunningWindow) { m_bRunningWindow = bRunningWindow; } private: bool m_bRunningWindow; HWND m_hWindow, m_hBtnStart, m_hBtnCancel, m_hLblResolution, m_hCbResolution, m_hLblBackBuffer, m_hCbBackBuffer, m_hLblDepthStencil, m_hCbDepthStencil, m_hLblVertexProcessing, m_hCbVertexProcessing, m_hLblMultiSampling, m_hCbMultiSampling, m_hLblAnisotropy, m_hCbAnisotropy; DWORD m_dwWidth, m_dwHeight, m_dwVertexProcessing, m_dwAnisotropy; D3DFORMAT m_ColorFormat, m_DepthStencilFormat; D3DMULTISAMPLE_TYPE m_MultiSampling; }; #endif Besides that, the only suspicious thing I see is fstream given in the first code. I did have it as fstream.h But VC++ was not recognizing it so I was told to remove the h and I did. now I am down to this error. and I have no clue what it could be. Possibly something obvious

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  • python crc32 woes

    - by lazyr
    I'm writing a python program to extract data from the middle of a 6 GB bz2 file. A bzip2 file is made up of independently decryptable blocks of data, so I only need to find a block (they are delimited by magic bits), then create a temporary one-block bzip2 file from it in memory, and finally pass that to the bz2.decompress function. Easy, no? The bzip2 format has a crc32 checksum for the file at the end. No problem, binascii.crc32 to the rescue. But wait. The data to be checksummed does not necessarily end on a byte boundary, and the crc32 function operates on a whole number of bytes. My plan: use the binascii.crc32 function on all but the last byte, and then a function of my own to update the computed crc with the last 1-7 bits. But hours of coding and testing has left me bewildered, and my puzzlement can be boiled down to this question: how come crc32("\x00") is not 0x00000000? Shouldn't it be, according to the wikipedia article? You start with 0b00000000 and pad with 32 0's, then do polynomial division with 0x04C11DB7 until there are no ones left in the first 8 bits, which is immediately. Your last 32 bits is the checksum, and how can that not be all zeroes? I've searched google for answers and looked at the code of several crc32 implementations without finding any clue to why this is so.

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  • How to write to a text file in pipe delimited format from SQL Server / ASP.Net?

    - by NJTechGuy
    I have a text file which needs to be constantly updated (regular intervals). All I want is the syntax and possibly some code that outputs data from a SQL Server database using ASP.Net. The code I have so far is : <%@ Import Namespace="System.IO" %> <script language="vb" runat="server"> sub Page_Load(sender as Object, e as EventArgs) Dim FILENAME as String = Server.MapPath("Output.txt") Dim objStreamWriter as StreamWriter ' If Len(Dir$(FILENAME)) > 0 Then Kill(FILENAME) objStreamWriter = File.AppendText(FILENAME) objStreamWriter.WriteLine("A user viewed this demo at: " & DateTime.Now.ToString()) objStreamWriter.Close() Dim objStreamReader as StreamReader objStreamReader = File.OpenText(FILENAME) Dim contents as String = objStreamReader.ReadToEnd() lblNicerOutput.Text = contents.Replace(vbCrLf, "<br>") objStreamReader.Close() end sub </script> <asp:label runat="server" id="lblNicerOutput" Font-Name="Verdana" /> With PHP, it is a breeze, but with .Net I have no clue. If you could help me with the database connectivity and how to write the data in pipe delimited format to an Output.txt file, that had be awesome. Thanks guys!

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  • Java Swing custom shapes (2D Graphics)

    - by juFo
    I need to draw custom shapes. Now when a user clicks on several points on the panel I create a shape using a polygon. public void mouseClicked(MouseEvent e) { polygon.addPoint(e.getX(), e.getY()); repaint(); } But I don't know if this is the best way to draw custom shapes. It should be possible to edit a drawn shape: resize change its fill color change the stroke color copy/paste it move a single point of the polygon ... I have seen people creating an own class implementing the Shape class and using a GeneralPath. But again I have no idea if this is a good way. Now I can create my own shape with a polygon (or with a GeneralPath) but I have no clue how to attach all the edit functions to my own shape (the edit functions I mean the resize, move, etc from above). I hope somebody could show me a way to do this or maybe write a little bit of code to demonstrate this. Thanks in advance!!

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  • Have to click twice to submit the form

    - by phil
    Intended function: require user to select an option from the drop down menu. After user clicks submit button, validate if an option is selected. Display error message and not submit the form if user fails to select. Otherwise submit the form. Problem: After select an option, button has to be clicked twice to submit the form. I have no clue at all.. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script src="jquery-1.4.2.min.js" type="text/javascript"></script> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <style> p{display: none;} </style> </head> <script> $(function(){ // language as an array var language=['Arabic','Cantonese','Chinese','English','French','German','Greek','Hebrew','Hindi','Italian','Japanese','Korean','Malay','Polish','Portuguese','Russian','Spanish','Thai','Turkish','Urdu','Vietnamese']; $('#muyu').append('<option value=0>Select</option>'); //loop through array for (i in language) //js unique statement for iterate array { $('#muyu').append($('<option>',{id:'muyu'+i,val:language[i], html:language[i]})) } $('form').submit(function(){ alert('I am being called!'); // check if submit event is triggered if ( $('#muyu').val()==0 ) {$('#muyu_error').show(); } else {$('#muyu_error').hide(); return true;} return false; }) }) </script> <form method="post" action="match.php"> I am fluent in <select name='muyu' id='muyu'></select> <p id='muyu_error'>Tell us your native language</p> <input type="submit" value="Go"> </form>

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  • algorithm - How to sort a 0/1 array with 2n/3 comparisons?

    - by Jackson Tale
    In Algorithm Design Manual, there is such an excise 4-26 Consider the problem of sorting a sequence of n 0’s and 1’s using comparisons. For each comparison of two values x and y, the algorithm learns which of x < y, x = y, or x y holds. (a) Give an algorithm to sort in n - 1 comparisons in the worst case. Show that your algorithm is optimal. (b) Give an algorithm to sort in 2n/3 comparisons in the average case (assuming each of the n inputs is 0 or 1 with equal probability). Show that your algorithm is optimal. For (a), I think it is fairly easy. I can choose a[n-1] as pivot, then do something like in quicksort partition, scan 0 to n - 2, find the middle point where left side is all 0 and right side is all 1, this take n - 1 comparisons. But for (b), I can't get a clue. It says "each of the n inputs is 0 or 1 with equal probability", so I guess I can assume the numbers of 0 and 1 equal? But how can I get a result which is related to 1/3? divide the whole array into 3 groups? Thanks

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  • Most efficient way to make an activity log

    - by Nathan
    I am making a "recent activity" tab to profiles on my site and I also am going to have a log for moderators to see everything that happens on the site. This would require making an activity log of some sort. I just don't know what would be better. I have 2 options: Make a table called "activity" and then every time someone does something, add a record to it with the type of action, user id, timestamp, etc. Problem: table could get very long. Join all 3 tables (questions, answers, answer_comments) and then somehow show all these on the page in the order in which the action was taken. Problem: this would be extremely hard because I have no clue how I could make it say "John commented on an answer on Question Title Here" by just joining 3 tables. Does anyone know of a better way of making an activity log in this situation? I am using PHP and MySQL. If this is either too inefficient or hard I will probably just forget the Recent Activity tab on profiles but I still need an activity log for moderators. Here's some SQL that I started making for option 2, but this would not work because there is no way of detecting whether the action is a comment, question, or answer when I echo the info in a while loop: SELECT q.*, a.*, ac.* FROM questions q JOIN answers a ON a.questionid = q.qid JOIN answer_comments ac ON c.answerid = a.ans_id WHERE q.user = $userid AND a.userid = $userid AND ac.userid = $userid ORDER BY q.created DESC, a.created DESC, ac.created DESC Thanks in advance for any help!

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  • Orbited exception Data must not be unicode.

    - by Sid
    I am working with orbited and once I switch on orbited in production mode it throws the following error on my screen -- <exception caught here> --- File "/usr/lib/python2.6/dist-packages/twisted/web/server.py", line 150, in process self.render(resrc) File "/usr/lib/python2.6/dist-packages/twisted/web/server.py", line 157, in render body = resrc.render(self) File "/usr/local/lib/python2.6/dist-packages/orbited-0.7.10-py2.6.egg/orbited/transports/base.py", line 21, in render self.conn.transportOpened(self) File "/usr/local/lib/python2.6/dist-packages/orbited-0.7.10-py2.6.egg/orbited/cometsession.py", line 322, in transportOpened self.cometTransport.flush() File "/usr/local/lib/python2.6/dist-packages/orbited-0.7.10-py2.6.egg/orbited/transports/base.py", line 45, in flush self.write(self.packets) File "/usr/local/lib/python2.6/dist-packages/orbited-0.7.10-py2.6.egg/orbited/transports/htmlfile.py", line 42, in write self.request.write(payload); File "/usr/lib/python2.6/dist-packages/twisted/web/http.py", line 862, in write self.transport.write(data) File "/usr/lib/python2.6/dist-packages/twisted/internet/tcp.py", line 420, in write abstract.FileDescriptor.write(self, bytes) File "/usr/lib/python2.6/dist-packages/twisted/internet/abstract.py", line 170, in write raise TypeError("Data must not be unicode") exceptions.TypeError: Data must not be unicode I have absolutely no clue as to what could be the problem. Could anyone point me in the right direction.

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  • How to deploy a single webapp with multiple web-modules that may be removed or added individually

    - by Daniel Bleisteiner
    We currently run two separate webapps (WARs) deployed in one single EAR containing additional JARs and settings. To improve our deployment I want to split one of these webapps into different modules that may be build and packaged individually. But I've currently no clue on how to package these modules so that I'm able to add or remove them as desired - at best during runtime. The webapp is getting more and more complex and I'd like to separate some of the functionality into modules. These modules should be packaged as single archives. As long as they contain only classes and resources loaded through code I know how to do this (simple JARs). But how about JSPs? Normally a WAR file contains JSPs or HTML files. I my case it are JSF pages utilizing JBoss Seam and RichFaces. These modules will add classes, resources and JSF pages and other includes to the running webapplication. Is it somehow possible to deploy them as individual archives to serve the same running webapp? We are using Maven for our build and packaging and deploy into JBoss v4.

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  • Releasing Autoreleasepool crashes on iOS 4.0 (and only on 4.0)

    - by samsam
    Hi there. I'm wondering what could cause this. I have several methods in my code that i call using performSelectorInBackground. Within each of these methods i have an Autoreleasepool that is being alloced/initialized at the beginning and released at the end of the method. this perfectly works on iOS 3.1.3 / 3.2 / 4.2 / 4.2.1 but it fataly crashes on iOS 4.0 with a EXC_BAD_ACCESS Exception that happens after calling [myPool release]. After I noticed this strange behaviour I was thinking about rewriting portions of my code and to make my app "less parallel" in case that the client os is 4.0. After I did that, the next point where the app crashed was within the ReachabilityCallback-Method from Apples Reachability "Framework". well, now I'm not quite sure what to do. The things i do within my threaded methods is pretty simple xml parsing (no cocoa calls or stuff that would affect the UI). After each method finishes it posts a notification which the coordinating-thread listens to and once all the parallelized methods have finished, the coordinating thread calls viewcontrollers etc... I have absolutely no clue what could cause this weird behaviour. Especially because Apples Code fails as well. any help is greatly appreciated! thanks, sam

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