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  • Qt drag & drop button; drop not detecting

    - by Thomas Verbeke
    I'm creating a 2D game in QT and i'm trying to implement a drag & drop into my program. For some reason the drop is not registered: qDebug should print a message on dropping but this doesn't happen. #include "dialog.h" #include "ui_dialog.h" #include "world.h" #include <vector> Dialog::Dialog(QWidget *parent) : QDialog(parent), ui(new Ui::Dialog) { ui->setupUi(this); scene = new QGraphicsScene(this); ui->graphicsView->setScene(scene); MySquare *item; QGraphicsRectItem *enemyItem; World *myWorld = new World(); std::vector<Tile*> tiles = myWorld->createWorld(":/texture.jpg"); int count = 0; foreach (Tile *tile, tiles){ count++; item = new MySquare(tile->getXPos()*4,tile->getYPos()*4,4,4); item->setBrush(QColor(tile->getValue()*255,tile->getValue()*255,tile->getValue()*255)); item->setAcceptDrops(true); scene->addItem(item); } player = new MySquare(10,20,10,10); player->setAcceptDrops(true); scene->addItem(player); //drag & drop part QPushButton *pushButton = new QPushButton("Click Me",this); connect(pushButton,SIGNAL(pressed()),this,SLOT(makeDrag())); setAcceptDrops(true); } void Dialog::makeDrag() { QDrag *dr = new QDrag(this); // The data to be transferred by the drag and drop operation is contained in a QMimeData object QMimeData *data = new QMimeData; data->setText("This is a test"); // Assign ownership of the QMimeData object to the QDrag object. dr->setMimeData(data); // Start the drag and drop operation dr->start(); } mysquare.cpp #include "mysquare.h" MySquare::MySquare(int _x,int _y, int _w, int _h) { isPlayer=false; Pressed=false; setFlag(ItemIsMovable); setFlag(ItemIsFocusable); setAcceptDrops(true); color=Qt::red; color_pressed = Qt::green; x = _x; y = _y; w = _w; h = _h; } QRectF MySquare::boundingRect() const { return QRectF(x,y,w,h); } void MySquare::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) { QRectF rec = boundingRect(); QBrush brush(color); if (Pressed){ brush.setColor(color); } else { brush.setColor(color_pressed); } painter->fillRect(rec,brush); painter->drawRect(rec); } void MySquare::mousePressEvent(QGraphicsSceneMouseEvent *event) { Pressed=true; update(); QGraphicsItem::mousePressEvent(event); qDebug() << "mouse Pressed"; } void MySquare::mouseReleaseEvent(QGraphicsSceneMouseEvent *event) { Pressed=false; update(); QGraphicsItem::mousePressEvent(event); qDebug() << "mouse Released"; } void MySquare::keyPressEvent(QKeyEvent *event){ int x = pos().x(); int y = pos().y(); //key handling QGraphicsItem::keyPressEvent(event); } void MySquare::dropEvent(QDropEvent *event) { qDebug("dropEvent - square"); // Unpack dropped data and handle it the way you want qDebug("Contents: %s", event->mimeData()->text().toLatin1().data()); } void MySquare::dragMoveEvent(QDragMoveEvent *event){ qDebug("dragMoveEvent - square "); event->accept(); } void MySquare::dragEnterEvent(QDragEnterEvent *event){ event->setAccepted(true); qDebug("dragEnterEvent - square"); event->acceptProposedAction(); } void MySquare::setBrush(QColor _color){ color = _color; color_pressed = _color; update(); //repaint } edit; there is no problem with qDebug() i'm just using it to test them i'm inside the drag events..which i'm not

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  • Core Data inserting objects

    - by Joe
    I'm trying to get my head around Core Data on the iphone. This is code from Apple's 'Navigation based app using Core data' template (method - insertNewObject) // Create a new instance of the entity managed by the fetched results controller. NSManagedObjectContext *context = [fetchedResultsController managedObjectContext]; NSEntityDescription *entity = [[fetchedResultsController fetchRequest] entity]; NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context]; It seems completely counter intuitive to me that the fetched results controller is used when inserting a new object. I changed the code to this: NSEntityDescription *entity = [NSEntityDescription entityForName:@"Event" inManagedObjectContext:managedObjectContext]; NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:managedObjectContext]; which works just as well and does not require access to the fetch request. Am I missing something here? Is there any good reason to use the fetched results controller in the insert method?

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  • How do I stop Emacs automatically inserting hyphens at the beginning of new lines in fundamental fil

    - by Bryce Thomas
    Hi there, I'm jotting down some notes in Emacs in Fundamental Fill mode. I'm starting each one of my notes with a "-" on a new line. The problem is, whenever one of the notes I'm writing is too long to fit on a single line, it gets pushed down to the next line (which I want to happen) but Emacs goes ahead and automatically inserts another "-" for me out the front on the new line (which I don't want to happen). Is there a way to stop Emacs from exhibiting this "helpful" behaviour?

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  • Vertical crosshair reposition on Google Map after map resize Issue

    - by joe
    I use the following function to add a crosshair to my Google Map. It works great for horizontal resizing. I can not figure out how to make it work for vertical. After resizing the map it requires the user to either zoom in or out 1 layer, upon which the crosshair snaps to center. var crosshairsSize=17; GMap2.prototype.addCrosshairs=function(){ var container=this.getContainer(); if(this.crosshairs){$(this.crosshairs).remove();} var crosshairs=document.createElement("img"); crosshairs.src='../images/crosshair2.gif'; crosshairs.style.width=crosshairsSize+'px'; crosshairs.style.height=crosshairsSize+'px'; crosshairs.style.border='0'; crosshairs.style.position='relative'; crosshairs.style.top=((parseInt(container.clientHeight)-crosshairsSize)/2)+'px'; crosshairs.style.left="0px"; // The map is centered so 0 will do crosshairs.style.zIndex='500'; container.appendChild(crosshairs); this.crosshairs=crosshairs; return crosshairs;}; I use map.checkResize(); and the map is correct, it's just the crosshair that is off. I've tried firing a javascript zoom in one level but it doesn't work like zooming in with the mouse. It's only zooming in/out with the mouse scroll wheel too... clicking and dragging the zoom slider doesn't work so somehow it's liking the mouse scroll wheel. Firing addCrosshairs(); after resize makes no difference. It places the new crosshair in old spot and still requires a mouse scroll zoom.

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  • pyparsing ambiguity

    - by Claudiu
    I'm trying to parse some text using PyParser. The problem is that I have names that can contain white spaces. So my input might look like this: Joe Bob Jimmy Foo Joe decides to eat. Bob decides to not eat. Jimmy Foo decides to eat. How can I create a parser for the decides to eat line? If I create my name parser naively, meaning with alphabetic characters plus space characters, then it will match the entire line.

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  • How do I search using the Google Maps API?

    - by Thomas
    Hello all, I'm trying to figure out how to search for nearby businesses in an iPhone app using the Google Maps API. I'm completely new to Javascript, and have waded through some of Google's sample code easily enough. I found how to grab the user's current location. Now I want to search for "restaurants" near that location. I'm just building on the sample code from here. I'll post it below with my changes anyway, just in case. <html> <head> <meta name="viewport" content="initial-scale=1.0, user-scalable=no" /> <meta http-equiv="content-type" content="text/html; charset=UTF-8"/> <title>Google Maps JavaScript API v3 Example: Map Geolocation</title> <script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=true"></script> <script type="text/javascript" src="http://code.google.com/apis/gears/gears_init.js"></script> <script type="text/javascript"> var currentLocation; var detroit = new google.maps.LatLng(42.328784, -83.040877); var browserSupportFlag = new Boolean(); var map; var infowindow = new google.maps.InfoWindow(); function initialize() { var myOptions = { zoom: 6, mapTypeId: google.maps.MapTypeId.ROADMAP }; map = new google.maps.Map(document.getElementById("map_canvas"), myOptions); map.enableGoogleBar(); // Try W3C Geolocation method (Preferred) if(navigator.geolocation) { browserSupportFlag = true; navigator.geolocation.getCurrentPosition(function(position) { // TRP - Save current location in a variable (currentLocation) currentLocation = new google.maps.LatLng(position.coords.latitude,position.coords.longitude); // TRP - Center the map around current location map.setCenter(currentLocation); }, function() { handleNoGeolocation(browserSupportFlag); }); } else { // Browser doesn't support Geolocation browserSupportFlag = false; handleNoGeolocation(browserSupportFlag); } } function handleNoGeolocation(errorFlag) { if (errorFlag == true) { // TRP - Default location is Detroit, MI currentLocation = detroit; contentString = "Error: The Geolocation service failed."; } else { // TRP - This should never run. It's embedded in a UIWebView, running on iPhone contentString = "Error: Your browser doesn't support geolocation."; } // TRP - Set the map to the default location and display the error message map.setCenter(currentLocation); infowindow.setContent(contentString); infowindow.setPosition(currentLocation); infowindow.open(map); } </script> </head> <body style="margin:0px; padding:0px;" onload="initialize()"> <div id="map_canvas" style="width:100%; height:100%"></div> </body> </html>

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  • Does JUnit4 testclasses require a public no arg constructor?

    - by Thomas Baun
    I have a test class, written in JUnit4 syntax, that can be run in eclipse with the "run as junit test" option without failing. When I run the same test via an ant target I get this error: java.lang.Exception: Test class should have public zero-argument constructor at org.junit.internal.runners.MethodValidator.validateNoArgConstructor(MethodValidator.java:54) at org.junit.internal.runners.MethodValidator.validateAllMethods(MethodValidator.java:39) at org.junit.internal.runners.TestClassRunner.validate(TestClassRunner.java:33) at org.junit.internal.runners.TestClassRunner.<init>(TestClassRunner.java:27) at org.junit.internal.runners.TestClassRunner.<init>(TestClassRunner.java:20) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:26) at junit.framework.JUnit4TestAdapter.<init>(JUnit4TestAdapter.java:24) at junit.framework.JUnit4TestAdapter.<init>(JUnit4TestAdapter.java:17) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:386) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:911) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:768) Caused by: java.lang.NoSuchMethodException: dk.gensam.gaia.business.bonusregulering.TestBonusregulerAftale$Test1Reader.<init>() at java.lang.Class.getConstructor0(Class.java:2706) at java.lang.Class.getConstructor(Class.java:1657) at org.junit.internal.runners.MethodValidator.validateNoArgConstructor(MethodValidator.java:52) I have no public no arg constructor in the class, but is this really necessary? This is my ant target <target name="junit" description="Execute unit tests" depends="compile, jar-test"> <delete dir="tmp/rawtestoutput"/> <delete dir="test-reports"/> <mkdir dir="tmp/rawtestoutput"/> <junit printsummary="true" failureproperty="junit.failure" fork="true"> <classpath refid="class.path.test"/> <classpath refid="class.path.model"/> <classpath refid="class.path.gui"/> <classpath refid="class.path.jfreereport"/> <classpath path="tmp/${test.jar}"></classpath> <batchtest todir="tmp/rawtestoutput"> <fileset dir="${build}/test"> <include name="**/*Test.class" /> <include name="**/Test*.class" /> </fileset> </batchtest> </junit> <junitreport todir="tmp"> <fileset dir="tmp/rawtestoutput"/> <report todir="test-reports"/> </junitreport> <fail if="junit. failure" message="Unit test(s) failed. See reports!"/> </target> The test class have no constructors, but it has an inner class with default modifier. It also have an anonymouse inner class. Both inner classes gives the "Test class should have public zero-argument constructor error". I am using Ant version 1.7.1 and JUnit 4.7

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  • Iframe Facebook application and cookies [Internet Explorer]

    - by Joe P
    I have downloaded the IBM P3P editor, created files and uploaded them to my server. And cookies are still not recognized in Internet Explorer. I've checked the P3P validation tool and it seems to validate. The application can be viewed here: apps.facebook.com/naplesnews and the iframe points to www.naplesnews.com/facebook/app/. Again www.naplesnews.com/facebook/app/ seems to validate with no issues as well. Any idea what I'm missing here?

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  • Why does this query only select a single row?

    - by Joe
    SELECT * FROM tbl_houses WHERE (SELECT HousesList FROM tbl_lists WHERE tbl_lists.ID = '123') LIKE CONCAT('% ', tbl_houses.ID, '#') It only selects the row from tbl_houses of the last occuring tbl_houses.ID inside tbl_lists.HousesList I need it to select all the rows where any ID from tbl_houses exists within tbl_lists.HousesList

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  • Servlet Exception + Class Cast Exception + Glassfish + Netbeans + JPA Entities + Vaadin

    - by Random Joe
    Hi all, I get this error: StandardWrapperValve[Vaadin Servlet]: PWC1406: Servlet.service() for servlet Vaadin Servlet threw exception java.lang.ClassCastException: com.delhi.entities.Category cannot be cast to com.delhi.entities.Category when I try to run my webapps on glassfish v2. Category is a JPA entity object the offending code according to the server log is: for (Category c : categories) { mymethod(); } categories is derived from: List<Category> categories = q.getResultList(); Any idea what went wrong?

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  • How do i compare 2 strings in shell?

    - by Thomas
    I want the user to input something at the command line either -l or -e. so e.g. $./report.sh -e I want an if statement to split up whatever decision they make so i have tried... if [$1=="-e"]; echo "-e"; else; echo "-l"; fi obviously doesn't work though Thanks

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  • How to nest joins with CakePHP?

    - by Daren Thomas
    I'm trying to behave. So, instead of using following SQL syntax: select * from tableA INNER JOIN tableB on tableA.id = tableB.tableA_id LEFT OUTER JOIN ( tableC INNER JOIN tableD on tableC.tableD_id = tableD.id) on tableC.tableA_id = tableA.id I'd like to use the CakePHP model->find(). This will let me use the Paginator too, since that will not work with custom SQL queries as far as I understand (unless you hardcode one single pagination query to the model which seems a little inflexible to me). What I've tried so far: /* inside tableA_controller.php, inside an action, e.g. "view" */ $this->paginate['recursive'] = -1; # suppress model associations for now $this->paginate['joins'] = array( array( 'table' => 'tableB', 'alias' => 'TableB', 'type' => 'inner', 'conditions' => 'TableB.tableA_id = TableA.id', ), array( 'table' => 'tableC', 'alias' => 'TableC', 'type' => 'left', 'conditions' => 'TableC.tableA_id = TableA.id', 'joins' = array( # this would be the obvious way to do it, but doesn't work array( 'table' => 'tableD', 'alias' => 'TableD', 'type' => 'inner', 'conditions' => 'TableC.tableD_id = TableD.id' ) ) ) ) That is, nesting the joins into the structure. But that doesn't work (CakePHP just ignores the nested 'joins' element which was kind of what I expected, but sad. I have seen hints in comments on how to do subqueries (in the where clause) using a statement builder. Can a similar trick be used here?

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  • Django Distinct on queryset in forms.py

    - by Thomas
    Hi all, I try to get a list with distinct into the forms.py like this: forms.ModelMultipleChoiceField(queryset=Events.objects.values('hostname'), required=False).distinct() In the python shell this command works perfect, but when trying it in forms.py leaves me a blank form, so nothing appears. When i just do Events.objects.all() the form appears, but distinct doesn't work with Events.objects.all()... i also tried values_list etc but doesn't seem to fit into the forms neither... anyone got an idea how to get a SELECT DISTINCT into a ModelMultipleChoiceField? I read some other questions about this at stackoverflow but nothing seems to work out with me, so hopefully someone knows how to do this in forms.py. Thxs in advance

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  • MYSQL - Help with a more complicated Query

    - by Joe
    I have two tables: tbl_lists and tbl_houses Inside tbl_lists I have a field called HousesList - it contains the ID's for several houses in the following format: 1# 2# 4# 51# 3# I need to be able to select the mysql fields from tbl_houses WHERE ID = any of those ID's in the list. More specifically, I need to SELECT SUM(tbl_houses.HouseValue) WHERE tbl_houses.ID IN tbl_lists.HousesList -- and I want to do this select to return the SUM for several rows in tbl_lists. Anyone can help? I'm thinking of how I can do this in a SINGLE query since I don't want to do any mysql "loops" (within PHP).

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  • CSS - Which method is better?

    - by Joe
    Which is better in regards to processing time but also taking into account ease of use for a developer? .font_small{ font-size:10px; } .font_blue{ color:blue; } .font_red{ color:red; } <span class="font_small font_blue">Hello World!</span><br /> <span class="font_small font_red">Today's the day!</span> OR .font_blue_small{ color:blue; } .font_red_small{ color:red; } .font_blue_small .font_red_small { font-size:10px; } <span class="font_blue_small">Hello World!</span><br /> <span class="font_red_small">Today's the day!</span> OR .font_blue_small{ color:blue; font-size:10px; } .font_red_small{ color:red; font-size:10px; } <span class="font_blue_small">Hello World!</span><br /> <span class="font_red_small">Today's the day!</span> OR Another option I haven't though of yet...?

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  • MySQL, C++: Retrieving auto-increment ID

    - by Thomas Matthews
    I have a table with an auto-incrementing ID. After inserting a new row, I would like to retrieve the new ID. I found an article that used the MySQL function LAST_INSERT_ID(). The article says to create a new query and submit it. I'm using MySQL Connector C++, Windows XP and Vista, and Visual Studio 9. Here are my questions: Is there an API, for the connector, that will fetch the ID out of the record? Does the result set, after an insert/append, contain the new ID? The LAST_INSERT_ID is MySQL specific. Is there an SQL standard method for obtaining the new ID?

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  • Help Reading Binary Image Data from SQL Server into PHP

    - by Joe Majewski
    I cannot seem to figure out a way to read binary data from SQL server into PHP. I am working on a project where I need to be able to store the image directly in the SQL table, not on the file system. Currently, I have been using a query like this one: INSERT INTO myTable(Document) SELECT * FROM OPENROWSET(BULK N'C:\image.jpg', SINGLE_BLOB) as BLAH This works fine to actually insert the image into the table, but I haven't yet figured a way to retrieve it and get my image back. I am doing this with PHP, and ultimately will have to make a stored procedure out of it, but can anyone enlighten me on a way to get that binary data (varbinary(MAX)) and generate an image on the fly. I expected it to be simple to use a SELECT statement and add a content-type to the headers that indicated it was an image, but it's simply not working. Instead, the page will just display the name of the file, which I have encountered in the past and understand it to be an error with the image data.

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  • What should a Java/SOA developer be able to do?

    - by Regular Joe
    I got assigned the task to list the activities a Java Developer should be able to perform and create an estimate about the time it would take. I've came up with the following: Create JDBC CRUD backend ( S=1d, M=5d, H=10d ) Create JSP/Servlet frontend for a CRUD app ( S=1d, M=10d, H=20d ) Create Swing desktop frontend ( S=1d, M=15d, H=30d) Create ORM based CRUD etc. Create Webapp fronend with webframework etc Where.. S = Small complexity M = Medium complexity H = High complexity 1d = 1 day This is thought for a Java "enterprise" developer. The other profile I have is SOA Developer, but I could not pass beyond: Create webservice ( S=.5d, M=2d, H=7d ) Q.- What other activities should a Java Developer be able to do? Q.- What activities should a SOA Developer be able to do? Please, help me with this, I know this is in the limit of the kind of questions that could be asked here, but I really need a little push on this, and I don't want to go to Yahoo Answers for this.

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  • Concise SSE and MMX instruction reference with latencies and throughput

    - by Joe
    I am trying to optimize some arithmetic by using the MMX and SSE instruction sets with inline assembly. However, I have been unable to find good references for the timings and usages of these enhanced instruction sets. Could you please help me find references that contain information about the throughput, latency, operands, and perhaps short descriptions of the instructions? So far, I have found: Intel Instruction References http://www.intel.com/Assets/PDF/manual/253666.pdf http://www.intel.com/Assets/PDF/manual/253667.pdf Intel Optimization Guide http://www.intel.com/Assets/PDF/manual/248966.pdf Timings of Integer Operations http://gmplib.org/~tege/x86-timing.pdf

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  • Why does jquery leak memory so badly?

    - by Thomas Lane
    This is kind of a follow-up to a question I posted last week: http://stackoverflow.com/questions/2429056/simple-jquery-ajax-call-leaks-memory-in-ie I love the jquery syntax and all of its nice features, but I've been having trouble with a page that automatically updates table cells via ajax calls leaking memory. So I created two simple test pages for experimenting. Both pages do an ajax call every .1 seconds. After each successful ajax call, a counter is incremented and the DOM is updated. The script stops after 1000 cycles. One uses jquery for both the ajax call and to update the DOM. The other uses the Yahoo API for the ajax and does a document.getElementById(...).innerHTML to update the DOM. The jquery version leaks memory badly. Running in drip (on XP Home with IE7), it starts at 9MB and finishes at about 48MB, with memory growing linearly the whole time. If I comment out the line that updates the DOM, it still finishes at 32MB, suggesting that even simple DOM updates leak a significant amount of memory. The non-jquery version starts and finishes at about 9MB, regardless of whether it updates the DOM. Does anyone have a good explanation of what is causing jquery to leak so badly? Am I missing something obvious? Is there a circular reference that I'm not aware of? Or does jquery just have some serious memory issues? Here is the source for the leaky (jquery) version: <html> <head> <script type="text/javascript" src="http://www.google.com/jsapi"></script> <script type="text/javascript"> google.load('jquery', '1.4.2'); </script> <script type="text/javascript"> var counter = 0; leakTest(); function leakTest() { $.ajax({ url: '/html/delme.x', type: 'GET', success: incrementCounter }); } function incrementCounter(data) { if (counter<1000) { counter++; $('#counter').text(counter); setTimeout(leakTest,100); } else $('#counter').text('finished.'); } </script> </head> <body> <div>Why is memory usage going up?</div> <div id="counter"></div> </body> </html> And here is the non-leaky version: <html> <head> <script type="text/javascript" src="http://yui.yahooapis.com/2.8.0r4/build/yahoo/yahoo-min.js"></script> <script type="text/javascript" src="http://yui.yahooapis.com/2.8.0r4/build/event/event-min.js"></script> <script type="text/javascript" src="http://yui.yahooapis.com/2.8.0r4/build/connection/connection_core-min.js"></script> <script type="text/javascript"> var counter = 0; leakTest(); function leakTest() { YAHOO.util.Connect.asyncRequest('GET', '/html/delme.x', {success:incrementCounter}); } function incrementCounter(o) { if (counter<1000) { counter++; document.getElementById('counter').innerHTML = counter; setTimeout(leakTest,100); } else document.getElementById('counter').innerHTML = 'finished.' } </script> </head> <body> <div>Memory usage is stable, right?</div> <div id="counter"></div> </body> </html>

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  • Why doesn't gcc remove this check of a non-volatile variable?

    - by Thomas
    This question is mostly academic. I ask out of curiosity, not because this poses an actual problem for me. Consider the following incorrect C program. #include <signal.h> #include <stdio.h> static int running = 1; void handler(int u) { running = 0; } int main() { signal(SIGTERM, handler); while (running) ; printf("Bye!\n"); return 0; } This program is incorrect because the handler interrupts the program flow, so running can be modified at any time and should therefore be declared volatile. But let's say the programmer forgot that. gcc 4.3.3, with the -O3 flag, compiles the loop body (after one initial check of the running flag) down to the infinite loop .L7: jmp .L7 which was to be expected. Now we put something trivial inside the while loop, like: while (running) putchar('.'); And suddenly, gcc does not optimize the loop condition anymore! The loop body's assembly now looks like this (again at -O3): .L7: movq stdout(%rip), %rsi movl $46, %edi call _IO_putc movl running(%rip), %eax testl %eax, %eax jne .L7 We see that running is re-loaded from memory each time through the loop; it is not even cached in a register. Apparently gcc now thinks that the value of running could have changed. So why does gcc suddenly decide that it needs to re-check the value of running in this case?

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  • [wxWidgets] How to store wxImage into database, using C++?

    - by Thomas Matthews
    I have some wxImages and I would like to store them into a BLOB (Binary Large OBject) field in a MySQL database. There are no methods in wxImage nor wxBitmap for obtaining the binary data as an array of unsigned char so I can load into the database. My current workaround is to write the image to a temporary file, then load the BLOB field directly from the file. Is there a more efficient method to load and store a wxImage object into a MySQL BLOB field? I am using MySql C++ connector 1.05, MS Visual Studio 2008, wxWidgets and C++.

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  • Tree Widgets on Rails

    - by Joe
    I would like to find some help building a tree interface in Rails. I've tried using jsTree but am having trouble integrating it properly into Rails. Thanks.

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  • Bypass django form validation on new form instance

    - by Thomas Schultz
    Hello! I have a situation where we are trying to autofill some form data on the second page of a signup and I was wondering if there's a way to bypass the entire form validation when we pass in only a couple of fields? so we have something like form = NewForm(request.POST) Where request.POST only contains some of the fields in NewForm(). So the page loads and there is feedback about how some fields are not filled in yet. This all happens from the GET request of the second page. Is there a way to do something like... form = NewForm(request.POST, validate=False)

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