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invite friends in a dialog in a Facebook application

- by Shani1351

I'm trying to create a Facebook application that displays a friend invite dialog within the application using Facebook's Javascript API (FB.ui). To do that I followed this tutorial I have two problems : The action url I've put in the request-form is "http://apps.facebook.com/appname/post_invite.php" but I see that the iframe source after the post is "http://mydomain.com/post_invite.php" and when this iframe tries to do : parent.closeInviteWidget(); I get an error saying : "Permission denied for < http: //mydomain.com (document.domain has not been set) to get property Window.closeInviteWidget from < http:// apps.facebook.com (document.domain=< http:// facebook.com)." The skip button inside the request-form opens the action url in a new window (new browser tab) and not post to itself like the invite button. How can I fix those problems? -------------------- UPDATE : -------------------------------- I've tried to do what ifaour said and changed the code to : function inviteFriends(user_name, category_id, category_name) { url = appBaseUrl + "/index.php?category_id=" + category_id; req = "<fb:req-choice url='" + url + "' label='Authorize My Application' />"; content = user_name + " opened a new category called " + category_name + ". " + req; action = 'post_invite.php'; fbmi_text = '<fb:request-form action="' + action + '" target="_self" method="post" invite="true" type="Invite" content="' + content + '" <fb:multi-friend-selector showborder="false" actiontext="Invite yor friends" email_invite="false" import_external_friends="false" /> </fb:request-form>'; FB.ui({ method:'fbml.dialog', width:'750px', fbml:fbmi_text }); } When I use FireBug and look at the invite form it looks like this: <form id="req_form_4d20682f73ddb6e71722794" content="I've opened a new category called dsfsd. <fb:req-choice url='http://apps.facebook.com/appname/index.php?category_id=60' label='Authorize My Application' /> type="Invite" invite="true" method="post" target="_self" action="http://apps.facebook.com/appname/post_invite.php"> ... </form> But I still get the same error : Permission denied for <http://mydomain.com> (document.domain has not been set) to get property Window.closeInviteWidget from <http://apps.facebook.com> (document.domain=<http://facebook.com>)...

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Simple Java question

- by user322102

Hi All I new to java so bare with me if this is a ridiculously simple question but I am curious about this method call which has {code} being taken in - see code below for an example in the method addSelectionListener. What is the purpose of this? I have been looking through docs for an explaination but cant seem to find what this practice is called never mind any useful information. setStatusLine.addSelectionListener(new SelectionAdapter() { public void widgetSelected(SelectionEvent e) { String message = "I would like to say hello to you."; if (pressed) { message = "Thank you for using me"; } setStatusLine(message); pressed = !pressed; } }); Thanks for any help or insights that can be offered

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Python - werid behavior

- by orokusaki

I've done what I shouldn't have done and written 4 modules (6 hours or so) without running any tests along the way. I have a method inside of /mydir/__init__.py called get_hash(), and a class inside of /mydir/utils.py called SpamClass. /mydir/utils.py imports get_hash() from /mydir/__init__. /mydir/__init__.py imports SpamClass from /mydir/utils.py. Both the class and the method work fine on their own but for some reason if I try to import /mydir/, I get an import error saying "Cannot import name get_hash" from /mydir/__init__.py. The only stack trace is the line saying that __init__.py imported SpamClass. The next line is where the error occurs in in SpamClass when trying to import get_hash. Why is this?

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Entity Aspect (in Spring)

- by niklassaers

Hi guys, I'm having a bit of a problem defining my aspects. I've got a bunch of entities that I'd like to profile the get-methods in, so I've written the following pointcut and method @Pointcut("execution(* tld.myproject.data.entities.*.get*()") public void getEntityProperty() {} @Around("getEntityProperty()") public Object profileGetEntityProperty(ProceedingJoinPoint pjp) throws Throwable { long start = System.currentTimeMillis(); String name = pjp.getSignature().getName(); Object output = pjp.proceed(); long elapsedTime = System.currentTimeMillis() - start; if(elapsedTime > 100) System.err.println("profileGetEntityProperty: Entity method " + name + " execution time: " + elapsedTime + " ms."); return output; } I've got weaving turned on in my configuration, and aspects weaving into the business layer work just fine. Is my pointcut correctly written? Or is there something about entities that make them non-weavable? (my entity is prefixed with @Entity before the class definition) Cheers Nik

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Enable Query Strings in Code Igniter

- by tarnfeld

Hey, I am trying to implement Twitter's OAuth into my Code Igniter web application at which the callback URL is /auth/ so once you have authenticated with Twitter you are taken to /auth/?oauth_token=SOME-TOKEN. I want to keep the nice clean URL's the framework provides using the /controller/method/ style of URL but I want to enable query strings as well, there will only ever be one name of the data oauth_token so it's ok if it has to be hard coded. Any ideas? I have tried tons of the things people are saying to do, but none work :( PS: I'm using the .htaccess method of URL rewriting.

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Constructor invokation returned null: what to do?

- by strager

I have code which looks like: private static DirectiveNode CreateInstance(Type nodeType, DirectiveInfo info) { var ctor = nodeType.GetConstructor(new[] { typeof(DirectiveInfo) }); if(ctor == null) { throw new MissingMethodException(nodeType.FullName, "ctor"); } var node = ctor.Invoke(new[] { info }) as DirectiveNode; if(node == null) { // ???; } return node; } I am looking for what to do (e.g. what type of exception to throw) when the Invoke method returns something which isn't a DirectiveNode or when it returns null (indicated by // ??? above). (By the method's contract, nodeType will always describe a subclass of DirectiveNode.) I am not sure when calling a constructor would return null, so I am not sure if I should handle anything at all, but I still want to be on the safe side and throw an exception if something goes wrong.

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Starting Frame-By-Frame Animation

- by OceanBlue

Hi, I have a basic question about starting a frame-by-frame animation. When I call the AnimationDrawable.start() method from my code directly, it doesn't seem to work. public void onCreate(Bundle savedInstanceState) { ... mAnimation.start(); ... } But if I put this line inside the onClick() callback method of a button, pressing the buton starts the animation. Why doesn't this line work in the code? Thanks!

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How Java Runtime Maps to Targets

- by zharvey

According to the Javadocs for Runtime here: Every Java application has a single instance of class Runtime that allows the application to interface with the environment in which the application is running. The current runtime can be obtained from the getRuntime method. An application cannot create its own instance of this class. My question is: what's their definition of an application? Is each JAR/WAR/EAR considered a standalone application? What about a plain ole' Driver.class class with a main() method? What about JEE containers that house EARs and EJBs? I guess I'm trying to understand how many Runtime instances could be up and running inside a complex (JEE) system. And understanding that requires me to understand what specific "things" constitute an "application" in Java terminology. Thanks in advance!

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Simple WCF question.

- by bearrito

So I am learning WCF and I have run across an issue that I believe has to do with Instance Control/State but I am not sure. Workflow is as follows, Basic client/server paradigm. The client calls a Method RetrieveBusinessObjects(criteria) and the server calls the datalayer and then puts them in an IList on the server side. It does not return this list to the calling Client. The client would then call a method say DisplayBusinessObjects() which would retrieve the IList from the Server, serialize them, bring them across the wire and display them. If i try this using the WCFTestClient it works. If I run it from an actual client then I get back an BusinessObject[] of size 0. Which to me indicates I had no objects to return. Is that a state mgmt issue or am I missing something?

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C# Property Access vs Interface Implementation

- by ehdv

I'm writing a class to represent a Pivot Collection, the root object recognized by Pivot. A Collection has several attributes, a list of facet categories (each represented by a FacetCategory object) and a list of items (each represented by a PivotItem object). Therefore, an extremely simplified Collection reads: public class Collection { private List<FacetCategory> categories; private List<PivotItem> items; // other attributes } What I'm unsure of is how to properly grant access to those two lists. Because declaration order of both facet categories and items is visible to the user, I can't use sets, but the class also shouldn't allow duplicate categories or items. Furthermore, I'd like to make the Collection object as easy to use as possible. So my choices are: Have Collection implement IList<PivotItem> and have accessor methods for FacetCategory: In this case, one would add an item to Collection foo by writing foo.Add(bar). This works, but since a Collection is equally both kinds of list making it only pass as a list for one type (category or item) seems like a subpar solution. Create nested wrapper classes for List (CategoryList and ItemList). This has the advantage of making a consistent interface but the downside is that these properties would no longer be able to serve as lists (because I need to override the non-virtual Add method I have to implement IList rather than subclass List. Implicit casting wouldn't work because that would return the Add method to its normal behavior. Also, for reasons I can't figure out, IList is missing an AddRange method... public class Collection { private class CategoryList: IList<FacetCategory> { // ... } private readonly CategoryList categories = new CategoryList(); private readonly ItemList items = new ItemList(); public CategoryList FacetCategories { get { return categories; } set { categories.Clear(); categories.AddRange(value); } } public ItemList Items { get { return items; } set { items.Clear(); items.AddRange(value); } } } Finally, the third option is to combine options one and two, so that Collection implements IList<PivotItem> and has a property FacetCategories. Question: Which of these three is most appropriate, and why?

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CGContextShowTextAtPoint: invalid context

- by coure06

I want to call a method responsible for drawing text on screen after each 5 seconds. Here is my code -(void) handleTimer: (NSTimer *)timer { CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, currentColor.CGColor); CGContextTranslateCTM(context, 145.0, 240.0); CGContextScaleCTM(context, 1.0, -1.0); CGContextSelectFont(context, "Arial", 18, kCGEncodingMacRoman); CGContextSetCharacterSpacing(context, 1); CGContextSetTextDrawingMode(context, kCGTextFillStroke); CGContextSetRGBStrokeColor(context, 0.5,0.5,1,1); CGContextShowTextAtPoint(context, 100, 100, "01", 2); } But after 5 seconds when this method is called i am getting this error CGContextShowTextAtPoint: invalid context Another thing is how to show a thinner font?

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How Do I create a synchronous version of NSURLConnection

- by quinn

I am using NSURLConnection inside of an NSIncrementalStore to synchronize my NSManagedObject with rest based web service built in Rails. I am aware of +sendSynchronousRequest:returningResponse:error but my understanding is that will not allow me to access such things as the HTTP response status code which I will need to properly handle the response, my understanding is sendSynchronousRequest returns the data if it responds in the 200 range and fails if it doesn't and doesn't really give you much more than that. I'm assuming I will somehow have to block the current method call after the NSURLConnection is instantiated and unblock it after NSURLConnection's delegate sets some value that can be returned by the blocked method. I'm assuming this will involve some combination of NSLock and NSThread but I really don't know where to start with this, any help will be greatly appreciated, thank you.

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Javascript to PHP, mysql uploading, one button pressing solution

- by user2897858

my program is generating buttons from a mysql database.When one of the button is pressed, it would uplod the current time and the gps coordinate. Sadly, it only works if the same button is pressed twice, but its not an option, because the button has to dissappear. I would like to have some help in coding how to make that possible the user only need to press the button once for the correct upload.Thanks in advance Here is the full code of my my file: <?php session_start(); ?> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>title</title> </head> <?php $maidatum=date("Ymj"); echo "<script>getLocation();</script>"; //Az adatbázishoz való csatlakozás $conn = mysql_connect("localhost","root","asd"); if(!($conn))die("Nincs conn a kiszolgálóval!".mysql_error()); $adatbazisneve="schtrans"; mysql_select_db($adatbazisneve,$conn); mysql_query("set names 'utf8'"); mysql_query("set character set 'utf8'"); //Combobox $sql = "SELECT Jaratszam,Vezeto FROM user"; $rs = mysql_query($sql) or die(mysql_error()); echo "<form action=\"\" method=\"post\">"; echo<<<nev <select name='Lista'> nev; while($row = mysql_fetch_array($rs)){ echo "<option value='".$row["Jaratszam"]."'>".$row["Vezeto"]."</option>"; }mysql_free_result($rs); echo "</select>"; ///Combox vége echo<<<lekerd <form action="" method="post"> <input type="submit" name="bekuldes" value="Lekérdez" /> </form> </form> lekerd; echo<<<gps <form action="" method="post"> <input type="hidden" name= "longitude" id="longitude"> <input type= "hidden" name ="latitude" id="latitude"> </form> gps; if(isset($_POST["bekuldes"])) { $jaratszam = $_POST['Lista']; $_SESSION['jaratsz']=$jaratszam; $lekerdez_parancs="SELECT * FROM cim_$maidatum WHERE jarat=$jaratszam;"; $lekerdez=mysql_query($lekerdez_parancs, $conn); echo "<table border=\"1\">"; echo "<td>Utánvétel</td> <td>Megrendelés összege</td> <td>ISZ</td> <td>Város</td> <td>Utca</td> <td>Megjegyzés</td> <td>Csomagok</td> <td>Raklaphely</td> <td>Súly</td><td>Térfogat</td><td>Latitude</td><td>Longitude</td><td>Ido</td>"; $g=1; //cimszámláló while ($adatok=mysql_fetch_array($lekerdez)) { echo "<tr>"; $_SESSION['adatok0'][$g]=$adatok[0]; echo "<td>$adatok[2]</td> <td>$adatok[3]</td> <td>$adatok[4]</td> <td>$adatok[5]</td> <td>$adatok[6]</td> <td>$adatok[7]</td> <td>$adatok[8]</td> <td>$adatok[9]</td> <td>$adatok[10]</td><td>$adatok[11]</td><td>$adatok[13]</td><td>$adatok[14]</td>"; if ($adatok[12]==null) { echo<<<gomb <form action="" method="post"> <td> <input type="hidden" name= "longitude" id="longitude$g"> <input type= "hidden" name ="latitude" id="latitude$g"> <input type="submit" name="ido" value="$g" /></td> </form> gomb; } else {echo "<td>$adatok[12]</td>";} $g++; } echo "</table>"; } if(isset($_POST["ido"])) { $hanyadik=$_POST["ido"]; $longitudee="longitude$hanyadik"; $latitudee="latitude$hanyadik"; ?> <script> var x=document.getElementById("log"); function getLocation() { if (navigator.geolocation) { navigator.geolocation.getCurrentPosition(showPosition); } else{x.innerHTML="GPS szolgáltatás nem müködik ezen a böngészon, kérlek értesítsd a rendszergazdát!";} } function showPosition(position) { var latitude = position.coords.latitude; var longitude = position.coords.longitude; document.getElementById("<?php echo $longitudee;?>").value = longitude; document.getElementById("<?php echo $latitudee;?>").value = latitude; } </script> <?php echo "<script>getLocation();</script>"; $latitude=$_POST["latitude"]; $longitude=$_POST["longitude"]; print_r($_POST); $currentime=date("H:i:s"); $acim=$_SESSION['adatok0'][$hanyadik]; $idofeltolt_parancs="UPDATE cim_$maidatum SET ido='$currentime',lat='$latitude',longi='$longitude' WHERE cimid='$acim';"; $feltoltes=mysql_query($idofeltolt_parancs, $conn) or die(mysql_error()); //tryy $jaratszam=$_SESSION['jaratsz']; $lekerdez_parancs="SELECT * FROM cim_$maidatum WHERE jarat=$jaratszam;"; $lekerdez=mysql_query($lekerdez_parancs, $conn); mysql_query("set names 'utf8'"); mysql_query("set character set 'utf8'"); echo "<table border=\"1\">"; echo "<td>Utánvétel</td> <td>Megrendelés összege</td> <td>ISZ</td> <td>Város</td> <td>Utca</td> <td>Megjegyzés</td> <td>Csomagok</td> <td>Raklaphely</td> <td>Súly</td><td>Térfogat</td><td>Latitude</td><td>Longitude</td><td>Ido</td>"; $g=1; //cimszámláló while ($adatok=mysql_fetch_array($lekerdez)) { echo "<tr>"; $_SESSION['adatok0'][$g]=$adatok[0]; echo "<td>$adatok[2]</td> <td>$adatok[3]</td> <td>$adatok[4]</td> <td>$adatok[5]</td> <td>$adatok[6]</td> <td>$adatok[7]</td> <td>$adatok[8]</td> <td>$adatok[9]</td> <td>$adatok[10]</td><td>$adatok[11]</td><td>$adatok[13]</td><td>$adatok[14]</td>"; if ($adatok[12]==null) { echo<<<gomb <form action="" method="post"> <td> <input type="hidden" name= "longitude" id="longitude$g"> <input type= "hidden" name ="latitude" id="latitude$g"> <input type="submit" name="ido" value="$g" /></td> </form> gomb; } else {echo "<td>$adatok[12]</td>";} $g++; } echo "</table>"; } mysql_close($conn); ?> </html>

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Enable editing does not call didSelectRowAtIndexPath ??

- by elementsense

Hi I have a UITableViewController where the user should be able to edit the items. In order to enable editing i use this : self.navigationItem.rightBarButtonItem = self.editButtonItem; And for everyone, how does not know where self.editButtonItem comes from, it is predefined by the SDK. So, now when I press on any item, this method is called : - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath but as soon as I hit the edit button and while editing is active, this method does not seemed to be called. Any idea what I missing ? This is the rest of the code that is related to editing : // Override to support conditional editing of the table view. - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath { // Return NO if you do not want the specified item to be editable. return YES; } - (UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath { return UITableViewCellEditingStyleNone; } - (BOOL)tableView:(UITableView *)tableView shouldIndentWhileEditingRowAtIndexPath:(NSIndexPath *)indexPath { return NO; } Thanks for the help. mcb

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IE 8 html parsing error message.

- by user48408

I'm experiencing the problem outlined in this kb article. http://support.microsoft.com/kb/927917 . Sorry I can't hyperlink cos i don't have enough points! "This problem occurs because a child container HTML element contains script that tries to modify the parent container element of the child container. The script tries to modify the parent container element by using either the innerHTML method or the appendChild method." The problem I'm having diagnosing the source of my problem is 2 fold: 1) This is only happening on some client machines (All are running IE8) and not others. How/Why only some? 2) I don't have any scripts which modify the innerHTML or call appendChild on any dom elements. I do have server side code which modify properties on asp .net server controls. (Essentially all thats happening is a panel control with some more controls is being made visbile or invisible on a button click), would these in turn then set the innerHTML property of the client rendered control(?)

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Insriting into a bitstream

- by evilertoaster

I'm looking for a way to efficiently insert bits into a bitstream and have it 'overflow', padding with 0's. So for example if you had a byte array with 2 bytes: 231 and 109 (11100111 01101101), and did BitInsert(byteArray,4,00) it would insert two bits at bit offset 4 making 11100001 11011011 01000000 (225,219,24). It would be ok even the method only allowed 1 bit insertions e.g. BitInsert(byteArray,4,true) or BitInsert(byteArray,4,false). I have one method of doing it, but it has to walk the stream with a bitmask bit by bit, so I'm wondering if there's a simpler approach... Answers in assembly or a C derivative would be appreciated.

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Python/C "defs" file - what is it?

- by detly

In the nautilus-python bindings, there is a file "nautilus.defs". It contains stanzas like (define-interface MenuProvider (in-module "Nautilus") (c-name "NautilusMenuProvider") (gtype-id "NAUTILUS_TYPE_MENU_PROVIDER") ) or (define-method get_mime_type (of-object "NautilusFileInfo") (c-name "nautilus_file_info_get_mime_type") (return-type "char*") ) Now I can see what most of these do (eg. that last one means that I can call the method "get_mime_type" on a "FileInfo" object). But I'd like to know: what is this file, exactly (ie. what do I search the web for to find out more info)? Is it a common thing to find in Python/C bindings? What is the format, and where is it documented? What program actually processes it? (So far, I've managed to glean that it gets transformed into a C source file, and it looks a bit like lisp to me.)

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iPhone: Setup static content of UITableView

- by Martin

This guide from apple https://developer.apple.com/iphone/prerelease/library/documentation/UserExperience/Conceptual/TableView_iPhone/TableViewCells/TableViewCells.html (you need login) explains how to use "The Technique for Static Row Content" to use Interface Builder to setup the cells in a tableview. I have some cells with different heights in my tableview. Without using the heightForRowAtIndexPath method everything get messed up. Do I still need to use this method or can I in some way setup the height of the cells inside the IB as I created them there? Also when using the "The Technique for Static Row Content" from the guide you still need to use the cellForRowAtIndexPath to setup the cells even if they are created in IB. I would like to setup the full layout of the tableview with all cells in IB (drag the cells right into the tableview), is that possible in some way? Thanks!

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Any way to have delayed_job execute some run-once code at startup and use across all jobs?

- by Rob Cameron

So I've got a delayed_job task that pushes some info to an XMPP server. Ideally you create a connection to XMPP once and then constantly push data to it, rather than creating a new connection every time you have some data to send. Is there any kind of facility in delayed_job for running a sort of 'setup' method when a worker starts, have it set some instance variables (like the XMPP connection object) that can then be used by all the jobs that come up? It's okay if each worker runs its own setup method. I just don't want every job (thousands per day) connecting to the XMPP server from scratch every time. Thanks for any help!

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How do you keep track of your programming TODOs?

- by Simucal

I'm one of those people who can't get anything done without a to-do list. If it isn't on the list it doesn't exist. Notepad Method: When I'm programming I've been keeping notepad open with a list of to-do's for my current project. I'll constantly re-arrange these based off priority and I cross them off and move them to the completed section when I'm finished with that particular task. Code Comments: Some programmers pepper their projects source code with: // TODO: Fix this completely atrocious code before anyone sees it Plus, I know that there are some tools that show you a list of all TODOs in your code as well. Website Task Tracker: Remember The Milk Backpack Manymoon Voo2do Gmail Tasks TeuxDeux TodoDodo Ta-da lists ... and many more What have you found to be the best method of keeping track of your to-do lists for multiple projects? Related Question: What can someone do to get organized around here? Related Question: Getting Organized; the to-do list.

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Why are nanosleep() and usleep() too slow?

- by user351990

I have a program that generates packets to send to a receiver. I need an efficient method of introducing a small delay between the sending of each packet so as not to overrun the receiver. I've tried usleep() and nanosleep() but they seem to be too slow. I've implemented a busy wait loop and had more success, but it's not the most efficient method, I know. I'm interested in anyone's experiences in trying to do what I'm doing. Do others find usleep() and nanosleep() to function well for this type of application? Thanks, Danny Llewallyn

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Common views in viewControllers - Code re-usability

- by Nitish

I have few common views in most of my viewControllers. What I noticed is that I can reuse single code for all viewControllers which is absolutely wise. For this I decided to create a class Utils which has static methods like +(void)createCommonViews:(float)yAxis:(NSString*)text; In my case common views are three labels and two images. Problem : I am not able to add these views from Utils. I am wondering how can I send self as a parameter so that I may add the views from Utils. It may be wrong to add views outside the viewController. In that case what can be the solution? Taking all these views in a UIView, setting return type of Utils method as UIView and then adding UIView to viewController(after calling method from viewController) might solve my problem. But what I am looking for is some other solution. Thanks, Nitish

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Direct comparator in Java out of the box

- by KARASZI István

I have a method which needs a Comparator for one of its parameters. I would like to pass a Comparator which does a normal comparison and a reverse comparator which does in reverse. java.util.Collections provides a reverseOrder() this is good for the reverse comparison, but I could not find any normal Comparator. The only solution what came into my mind is Collections.reverseOrder(Collections.reverseOrder()). but I don't like it because the double method calling inside. Of course I could write a NormalComparator like this: public class NormalComparator<T extends Comparable> implements Comparator<T> { public int compare(T o1, T o2) { return o1.compareTo(o2); } } But I'm really surprised that Java doesn't have a solution for this out of the box.

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approximating log10[x^k0 + k1]

- by Yale Zhang

Greetings. I'm trying to approximate the function Log10[x^k0 + k1], where .21 < k0 < 21, 0 < k1 < ~2000, and x is integer < 2^14. k0 & k1 are constant. For practical purposes, you can assume k0 = 2.12, k1 = 2660. The desired accuracy is 5*10^-4 relative error. This function is virtually identical to Log[x], except near 0, where it differs a lot. I already have came up with a SIMD implementation that is ~1.15x faster than a simple lookup table, but would like to improve it if possible, which I think is very hard due to lack of efficient instructions. My SIMD implementation uses 16bit fixed point arithmetic to evaluate a 3rd degree polynomial (I use least squares fit). The polynomial uses different coefficients for different input ranges. There are 8 ranges, and range i spans (64)2^i to (64)2^(i + 1). The rational behind this is the derivatives of Log[x] drop rapidly with x, meaning a polynomial will fit it more accurately since polynomials are an exact fit for functions that have a derivative of 0 beyond a certain order. SIMD table lookups are done very efficiently with a single _mm_shuffle_epi8(). I use SSE's float to int conversion to get the exponent and significand used for the fixed point approximation. I also software pipelined the loop to get ~1.25x speedup, so further code optimizations are probably unlikely. What I'm asking is if there's a more efficient approximation at a higher level? For example: Can this function be decomposed into functions with a limited domain like log2((2^x) * significand) = x + log2(significand) hence eliminating the need to deal with different ranges (table lookups). The main problem I think is adding the k1 term kills all those nice log properties that we know and love, making it not possible. Or is it? Iterative method? don't think so because the Newton method for log[x] is already a complicated expression Exploiting locality of neighboring pixels? - if the range of the 8 inputs fall in the same approximation range, then I can look up a single coefficient, instead of looking up separate coefficients for each element. Thus, I can use this as a fast common case, and use a slower, general code path when it isn't. But for my data, the range needs to be ~2000 before this property hold 70% of the time, which doesn't seem to make this method competitive. Please, give me some opinion, especially if you're an applied mathematician, even if you say it can't be done. Thanks.

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Simulating a mouse button click in Windows

- by Ncarlson

Hi everyone, I'm writing Remote Desktop clone in C++ using QT. So far I'm able to move the mouse cursor around fine. QT has a nice setPos function for that. However, I'm a bit lost as to what API/Library to use for simulating mouse button clicks. One method I'm aware of is to send the WM_(event) to a window using the window's HWND. However, I was hoping there was a more salient method for taking complete control over a mouse. Is there any other way to tell the operating system that the left mouse button has been clicked? Thanks.

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