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  • Suitable data structures for saving files in localStorage (HTML5) ?

    - by WmasterJ
    It is nice when there isn't a DB to maintain and users to authenticate. My professor has asked me to convert a recent research project of his that uses Bespin and calculates errors made by users in a code editor as part of his research. The goal is to convert from MySQL to using HTML5 localStorage completely. Doesn't seem so hard to do, even though digging in his code might take some time. Question: I need to store files and state (last placement of cursor and active file). I have already done so by implementing the recommendations in another stackoverflow thread. But would like your input considering how to structure the content to use. My current solution Hashmap like solution with javascript objects: files = {}; // later, saving files[fileName] = data; And then storing in localStorage using some recommendations localStorage.setObject("files", files); // Note that setObject(key, data) does not exist but is added // using Storage.prototype.setObject = function() {... Currently I'm also considering using some type of numeric id. So that names can be changed without any hassle renaming the key in the hashmap. What is your opinion on the way it is solved and would you do it any differently?

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  • Same random numbers from instantiated class

    - by user1797202
    I'm learning C# and created a class within my program that holds a random number generator: class RandomNumberGenerator { Random RNG = new Random(); // A bunch of methods that use random numbers are in here } Inside this class are a few methods that use the RNG. Data gets sent here from other parts of the program, gets processed, then gets returned. One of the methods does the following: // Method works something like this int Value1 = RNG.Next(x, y); int Value2 = RNG.Next(x, y); int Value3 = RNG.Next(x, y); The x, y values are to be sent here from another class. So, I have to create an instance of the RandomNumberGenerator within that class so I can call its methods and pass the x and y values to it. class DoStuff { RandomNumberGenerator Randomizer = new RandomNumberGenerator // Here I call a bunch of Randomizer methods that give me values I need } The problem in the above method is that I get the same numbers every time for all three values. I'm not sure if it's because they're so close together and Randomizer's seed value hasn't had time to change or if I'm doing something wrong when I create a new instance of the RandomNumberGenerator class. I've gone through a bunch of answers on here already and typically problems like this are due to people creating many new Random objects when they run methods (thus setting the seed for all of them to the same value), but the only new Random object I create is within the RandomNumberGenerator class. I then instantiate that once within the other class so I can pass it data and use its methods. Why is this happening and how would I fix this?

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  • Get value of selected field from a dropdown list

    - by 47
    I have this class in my model: class ServiceCharge(models.Model): name = models.CharField(max_length=30) amount = models.PositiveIntegerField() extends_membership = models.BooleanField(default=False) def __unicode__(self): return str(self.name) What I want to have is in the form for charging users a service charge, when a charge is selected from the dropdown menu, the two values for amount and extends_membership are updated on the form depending on the selected charge. My forms.py: class vModelChoiceField(forms.ModelChoiceField): def label_from_instance(self, obj): return "%s" % obj.name class PayServiceChargeForm(PaymentsForm): service_charge = vModelChoiceField(queryset=ServiceCharge.objects.all(), empty_label=" ") class Meta(PaymentsForm.Meta): exclude = ('member', 'payment_type', 'transacted_by', 'description') Then the form template: <table border="0"> <tr> <td><strong>{% trans "Service Charge" %}</strong></td> <td>{{ form.service_charge }}</td> <td><strong>{% trans "Extends Membership" %}</strong></td> <td>{{ form.extends_membership }}</td> </tr> <tr> <td valign="top"><strong>{% trans "Expiry Date" %}</strong></td> <td valign="top">{{ form.expiry_date }}</td> <td valign="top"><strong>{% trans "Amount" %}</strong></td> <td>{{ form.amount }}</td> </tr> </table> I was trying out some jQuery but I got stuck after getting the currently selected charge: <script type="text/javascript"> $(document).ready(function(){ $("#id_service_charge").change(onSelectChange); }); function onSelectChange(){ var selected = $("#id_service_charge option:selected"); var output = ""; if(selected.val() != 0){ charge = selected.val(); .... (update values) .... } } </script>

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  • C#: How to get all public (both get and set) string properties of a type

    - by Svish
    I am trying to make a method that will go through a list of generic objects and replace all their properties of type string which is either null or empty with a replacement. How is a good way to do this? I have this kind of... shell... so far: public static void ReplaceEmptyStrings<T>(List<T> list, string replacement) { var properties = typeof(T).GetProperties( -- What BindingFlags? -- ); foreach(var p in properties) { foreach(var item in list) { if(string.IsNullOrEmpty((string) p.GetValue(item, null))) p.SetValue(item, replacement, null); } } } So, how do I find all the properties of a type that are: Of type string Has public get Has public set ? I made this test class: class TestSubject { public string Public; private string Private; public string PublicPublic { get; set; } public string PublicPrivate { get; private set; } public string PrivatePublic { private get; set; } private string PrivatePrivate { get; set; } } The following does not work: var properties = typeof(TestSubject) .GetProperties(BindingFlags.Instance|BindingFlags.Public) .Where(ø => ø.CanRead && ø.CanWrite) .Where(ø => ø.PropertyType == typeof(string)); If I print out the Name of those properties I get there, I get: PublicPublic PublicPrivate PrivatePublic In other words, I get two properties too much. Note: This could probably be done in a better way... using nested foreach and reflection and all here... but if you have any great alternative ideas, please let me know cause I want to learn!

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  • Using h:outputFormat to message-format the f:selectItems of a h:selectOneRadio

    - by msharma
    I am having some trouble with using h:selectOneRadio. I have a list of objects which is being returned which needs to be displayed. I am trying something like this: <h:selectOneRadio id="selectPlan" layout="pageDirection"> <f:selectItems value="#{detailsHandler.planList}" /> </h:selectOneRadio> and planList is a List of Plans. Plan is defined as: public class Plan { protected String id; protected String partNumber; protected String shortName; protected String price; protected boolean isService; protected boolean isOption; //With all getters/setters } The text that must appear for each radio button is actually in a properties file, and I need to insert params in the text to fill out some value in the bean. For example the text in my properties file is: plan_price=The price of this plan is {0}. I was hoping to do something like this: <f:selectItems value="<h:outputFormat value="#{i18n.plan_price}"> <f:param value="#{planHandler.price}"> </h:outputFormat>" /> Usually if it's not a h:selectOneRadio component, if it's just text I use the h:outputFormat along with f:param tags to display the messages in my .property file called i18n above, and insert a param which is in the backing bean. here this does not work. Does anyone have any ideas how I can deal with this? I am being returned a list of Plans each with their own prices and the text to be displayed is held in property file. Any help much appreciated. Thanks!

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  • Can a PHP object respond to an undefined method?

    - by Nathan Long
    Rails relies on some of the neat aspects of Ruby. One of those is the ability to respond to an undefined method. Consider a relationship between Dog and Owner. Owner has_many :dogs and Dog belongs_to :owner. If you go into script/console, get a dog object with fido = Dog.find(1), and look at that object, you won't see a method or attribute called Owner. What you will see is an owner_id. And if you ask for fido.owner, the object will do something like this (at least, this is how it appears to me): I'm being asked for my .owner attribute. I don't have one of those! Before I throw a NoMethodError, do I have a rule about how to deal with this? Yes, I do: I should check and see if I have an owner_id. I do! OK, then I'll do a join and return that owner object. PHP's documentation is - ahem - a bit lacking sometimes, so I wonder if anyone here knows the answer to this: Can I define similar behavior for objects in PHP? If not, do you know of a workaround for flexible model joins like these?

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  • Define "Validation in the Model"

    - by sunwukung
    There have been a couple of discussions regarding the location of user input validation: http://stackoverflow.com/questions/659950/should-validation-be-done-in-form-objects-or-the-model http://stackoverflow.com/questions/134388/where-do-you-do-your-validation-model-controller-or-view These discussions were quite old, so I wanted to ask the question again to see if anyone had any fresh input. If not, I apologise in advance. If you come from the Validation in the Model camp - does Model mean OOP representation of data (i.e. Active Record/Data Mapper) as "Entity" (to borrow the DDD terminology) - in which case you would, I assume, want all Model classes to inherit common validation constraints. Or can these rules simply be part of a Service in the Model - i.e. a Validation service? For example, could you consider Zend_Form and it's validation classes part of the Model? The concept of a Domain Model does not appear to be limited to Entities, and so validation may not necessarily need to be confined to this Entities. It seems that you would require a lot of potentially superfluous handing of values and responses back and forth between forms and "Entities" - and in some instances you may not persist the data recieved from user input, or recieve it from user input at all.

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  • Android Facebook RequestListener

    - by Marcus King
    I'm new to Java, but have been a .NET developer for years now and I am a bit confused about the point of the RequestListener object as I can't retrieve the results of my asynchronous calls on the UI thread from what I can tell. My research has told me I should not use singletons or the application context object for getting and storing data. I could use sqlLite, but the data I need is too transient to bother. I would like to know how to have the asyncfacebookrunner object report back it's responses to the UI thread so I can proceed to make decisions between my own api and the objects returned to me from the facebook calls I am making in the async calls. Am I missing something? I can't seem to find a way to get data out. I can pass a Bundle in, but I'm not too sure how to get data out. I would think I would pass it an Intent object to retrieve, but I am not seeing it. I think my eyes are crossed from lack of sleep at this point. Any help here?

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  • Querying XML using node numbers

    - by CP
    Okay, so I'm writing a utility that compares 2 XML documents using Microsoft's XML diff patch tool. The result looks something like this: <?xml version="1.0" encoding="utf-16"?><xd:xmldiff version="1.0" srcDocHash="10728157883908851288" options="IgnoreChildOrder IgnoreComments IgnoreWhitespace " fragments="yes" xmlns:xd="http://schemas.microsoft.com/xmltools/2002/xmldiff"><xd:node match="1"><xd:node match="1"><xd:node match="1"><xd:node match="2"><xd:node match="1"><xd:node match="1"><xd:node match="2"><xd:change match="1">testi22n2123</xd:change></xd:node></xd:node><xd:add match="/1/1/1/2/1/8" opid="1" /><xd:node match="7"><xd:node match="1"><xd:change match="1">31</xd:change></xd:node><xd:node match="2"><xd:change match="1">test2ing</xd:change></xd:node></xd:node><xd:remove match="8" opid="1" /></xd:node></xd:node></xd:node></xd:node></xd:node><xd:descriptor opid="1" type="move" /></xd:xmldiff> What I'm trying to do is go back into the source document and get the source data that represents the difference. I initially tried creating an Xpath query, but as I understand it now this XmlDiff thing works off the DOM... which seems like the dinosaur of XML objects these days. What's the best way to get at the node in the source XML by using the numbers provided in the diff result?

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  • rbind.zoo doesn't seem create consistent zoo object

    - by a-or-b
    I want to rbind.zoo two zoo object together. When I was testing I came across the following issue(?)... Note: The below is an example, there is clearly no point to it apart from being illustrative. I have an zoo object, call it, 'X'. I want to break it into two parts and then rbind.zoo them together. When I compare it to the original object then all.equal gives differences. It appears that the '$class' attribute differs, but I can't see how or why. Is I make these xts objects then the all.equal works as expected. i.e. ..... X.date <- as.POSIXct(paste("2003-", rep(1:4, 4:1), "-", sample(1:28, 10, replace = TRUE), sep = "")) X <- zoo(matrix(rnorm(24), ncol = 2), X.date) a <- X[c(1:3), ] # first 3 elements b <- X[c(4:6), ] # second 3 elements c <- rbind.zoo(a, b) # rbind into an object of 6 elements d <- X[c(1:6), ] # all 6 elements all.equal(c, d) # are they equal? ~~~~ all.equal gives me the following difference: "Attributes: < Component 3: Attributes: < Length mismatch: comparison on first 1 components "

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  • Handling large (object) datasets with PHP

    - by Aron Rotteveel
    I am currently working on a project that extensively relies on the EAV model. Both entities as their attributes are individually represented by a model, sometimes extending other models (or at least, base models). This has worked quite well so far since most areas of the application only rely on filtered sets of entities, and not the entire dataset. Now, however, I need to parse the entire dataset (IE: all entities and all their attributes) in order to provide a sorting/filtering algorithm based on the attributes. The application currently consists of aproximately 2200 entities, each with aproximately 100 attributes. Every entity is represented by a single model (for example Client_Model_Entity) and has a protected property called $_attributes, which is an array of Attribute objects. Each entity object is about 500KB, which results in an incredible load on the server. With 2000 entities, this means a single task would take 1GB of RAM (and a lot of CPU time) in order to work, which is unacceptable. Are there any patterns or common approaches to iterating over such large datasets? Paging is not really an option, since everything has to be taken into account in order to provide the sorting algorithm.

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  • C++ Iterator Pipelining Designs

    - by Kirakun
    Suppose we want to apply a series of transformations, int f1(int), int f2(int), int f3(int), to a list of objects. A naive way would be SourceContainer source; TempContainer1 temp1; transform(source.begin(), source.end(), back_inserter(temp1), f1); TempContainer2 temp2; transform(temp1.begin(), temp1.end(), back_inserter(temp2), f2); TargetContainer target; transform(temp2.begin(), temp2.end(), back_inserter(target), f3); This first solution is not optimal because of the extra space requirement with temp1 and temp2. So, let's get smarter with this: int f123(int n) { return f3(f2(f1(n))); } ... SourceContainer source; TargetContainer target; transform(source.begin(), source.end(), back_inserter(target), f123); This second solution is much better because not only the code is simpler but more importantly there is less space requirement without the intermediate calculations. However, the composition f123 must be determined at compile time and thus is fixed at run time. How would I try to do this efficiently if the composition is to be determined at run time? For example, if this code was in a RPC service and the actual composition--which can be any permutation of f1, f2, and f3--is based on arguments from the RPC call.

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  • NSMutableArray for Object which has NSString property causes memory leak

    - by user262325
    Hello everyone I hope to add objects to a NSMutableArray "myArray", The NSMutableArray is the array for FileObj which has a NSString property "fileName" #import <UIKit/UIKit.h> @interface FileObj : NSObject { NSString *fileName; } -(void) setfileName:(NSString *)s ; -(NSString *) getfileName ; @end // // File.m// #import "File.h" @implementation FileObj -(void) setfileName:(NSString *)s ; { fileName=s; } -(NSString *) getfileName ; { return fileName; } @end I initialize the myArray here: NSMutableArray *temarray; temarray=[[NSMutableArray alloc] init]; self.myArray=temarray; [temarray release]; the codes to add object to myArray FileObj *newobj=[[FileObj alloc]init ]; NSString *fieldValue2 = [[NSString alloc] initWithUTF8String:@"aaaa"]; [newobj setfileName:fieldValue2]; [myArray addObject:newobj]; [fieldValue2 release]; //**if I enabled the line, it will cause crash** //**if I disable the line, it will cause memory leak** [newobj release]; Welcome any comment Thanks interdev

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  • How to get number of bytes read from QTextStream

    - by user261882
    The following code I am using to find the number of read bytes from QFile. With some files it gives the correct file size, but with some files it gives me a value that is approximatively fileCSV.size()/2. I am sending two files that have same number of characters in it, but have different file sizes link text. Should i use some other objects for reading the QFile? QFile fileCSV("someFile.txt"); if ( !fileCSV.open(QIODevice::ReadOnly | QIODevice::Text)) emit errorOccurredReadingCSV(this); QTextStream textStreamCSV( &fileCSV ); // use a text stream int fileCSVSize = fileCSV.size()); qint64 reconstructedCSVFileSize = 0; while ( !textStreamCSV.atEnd() ) { QString line = textStreamCSV.readLine(); // line of text excluding '\n' if (!line.isEmpty()) { reconstructedCSVFileSize += line.size(); //this doesn't work always reconstructedCSVFileSize += 2; } else reconstructedCSVFileSize += 2; } I know that reading the size of QString is wrong, give me some other solutions if you can. Thank you.

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  • Which way to store this data is effective?

    - by Tattat
    I am writing a game, which need a map, and I want to store the map. The first thing I can think of, is using a 2D-array. But the problem is what data should I store in the 2D-array. The player can tap different place to have different reaction. So, I am thinking store a 2D-array with objects, when player click some position, and I find it in the array, and use the object in that array to execute a cmd. But I have a concern that storing lots of object may use lots of memory. So, I am think storing char/int only. But it seems that not enough for me. I want to store the data like that: { Type:1 Color:Green } No matter what color is, if they are all type 1, the have same reactions in logic, but the visual effect is based on the color. So, it is not easy to store using a prue char/int data, unless I make something like this: 1-5 --> all type 1. 1=color green , 2=color red, 3 = color yellow.... ... 6-10 --> all type 2. 2 = color green, 2 = color red ... ... So, do you have any ideas on how to minimize the ram use, but also easy for me to read... ...thx

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  • Mixing stored procedures and ORM

    - by Jason
    The company I work for develops a large application which is almost entirely based on stored procedures. We use classic ASP and SQL Server and the major part of the business logic is contained inside those stored procedures. For example, (I know, this is bad...) a single stored procedure can be used for different purposes (insert, update, delete, make some calculations, ...). Most of the time, a stored procedure is used for operations on related tables, but this is not always the case. We are planning to move to ASP.NET in a near future. I have read a lot of posts on StackOverflow recommending that I move the business logic outside the database. The thing is, I have tried to convince the people who takes the decisions at our company and there is nothing I can do to change their mind. Since I want to be able to use the advantages of object-oriented programming, I want to map the tables to actual classes. So far, my solution is to use an ORM (Entity Framework 4 or nHibernate) to avoid mapping the objects manually (mostly to retrieve the data) and use some kind of Data Access Layer to call the existing stored procedures (for saving). I want your advice on this. Do you think it is a good solution? Any ideas?

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  • Wrapping a Flash/AS3 Sprite as a Flex MXML component

    - by John
    For my game, I am making the main game view as a plain Flash/AS3 class, something like: public class GameArena extends Sprite This is simply a big rectangle in which game objects are drawn, so no need for fancy UI and I want to keep the main game engine Flex-free so I can use Sprites rather than heavier Flex components. However for the entire game/app, I do still want to use Flex for GUI/layout. So I thought I could create a Flex class subclassing UIComponent, which has a GameView object as a child... now I can use this in MXML as a standard Flex component. e.g. public class ArenaView extends UIComponent { public var gameArena:GameArena; override protected function createChildren():void { super.createChildren(); if (!gameArena) { gameArena = new GameArena(); gameArena.width = 200; gameArena.height = 200; addChild(gameArena); } } } Then I have a simple line in my main App MXML like: <logic:Arena x="0" y="0" width="50%" height="100%" name="TestArenaPanel" /> But so far while my code compiles, the Flash class isn't getting rendered. Maybe it's something simple, but I wanted to ask if this is a reasonable approach, or there is something better? BTW: I've had the "should Flex be used" conversation many times. If you want to discuss that please do so in comments, but keep answers on topic.

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  • Overlapping audio in IE when I show/hide videos

    - by user1062448
    I have a thumbnail list with links to individual videos. Everything works fine in all browsers but IE. In IE, if I start a video and (without slicking pause or stop) click on the thumbnail for the next video, the audio continues playing. In other words, the audio for both videos plays at once. Any suggestions? HTML: <ul class="videoButtons"> <li><a class="vidButton" href="javascript:void(0)" id="1" ><img src="images/videoPics/vid1Thumb.jpg" /><br />video title</a></li> <li><a class="vidButton" href="javascript:void(0)" id="2" ><img src="images/videoPics/vid2Thumb.jpg" /><br />video title</a></li> <li><a class="vidButton" href="javascript:void(0)" id="3" ><img src="images/videoPics/vid3Thumb.jpg" /><br />video title</a></li> </ul> <div class="box" id="video1"> <!--flv embedded object - FLVPlayer--> </div> <div class="box" id="video2"> <!--flv embedded object - FLVPlayer1--> </div> <div class="box" id="video3"> <!--flv embedded object - FLVPlayer2--> </div> Show/Hide code: $(".vidButton").click(function() { var buttonID = $(this).attr('id'); // get ID of the button clicked var video = $('#'+'video'+buttonID); // add ID number to video $('.box').hide(); // hide all other divs video.fadeTo("slow", 1); // show video }); }); // video objects swfobject.registerObject("FLVPlayer"); swfobject.registerObject("FLVPlayer1"); swfobject.registerObject("FLVPlayer2");

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  • Fast find object by string property

    - by Andrew Kalashnikov
    Hello, colleagues. I've got task to fast find object by its string property. Object: class DicDomain { public virtual string Id{ get; set; } public virtual string Name { get; set; } } For storing my object I use List[T] dictionary where T is DicDomain for now . I've got 5-10 such lists, which contain about 500-20000 at each one. Task is find objects by its Name. I use next code now: List<T> entities = dictionary.FindAll(s => s.Name.Equals(word, StringComparison.OrdinalIgnoreCase)); I've got some questions: Is my search speed optimal. I think now. Data structure. It List good for this task. What about hashtable,sorted... Method Find. May be i should use string intern?? I haven't much exp at these tasks. Can u give me good advice for increase perfomance. Thanks

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  • java + increasing performance and scalability

    - by varun
    Hi, below is the a code snippet, which returns the object of a class. now the object is basially comparing to some parameter in loop. my concern is what if there are thousands of objects in loop, in that case performance and scalability can be an issue. please suggest how to improve this code for performance part public Widget get(String name,int major,int minor,boolean exact) { Widget widgetToReturn = null; if(exact) { Widget w = new Widget(name, major, minor); // for loop using JDK 1.5 version for(Widget wid : set) { if((w.getName().equals(wid.getName())) && (wid.getVersion()).equals(w.getVersion())) { widgetToReturn = w; break; } } } else { Widget w = new Widget(name, major, minor); WidgetVersion widgetVersion = new WidgetVersion(major, minor); // for loop using JDK 1.5 version for(Widget wid : set) { WidgetVersion wv = wid.getVersion(); if((w.getName().equals(wid.getName())) && major == wv.getMajor() && WidgetVersion.isCompatibleAndNewer(wv, widgetVersion)) { widgetToReturn = wid; } else if((w.getName().equals(wid.getName())) && wv.equals(widgetVersion.getMajor(), widgetVersion.getMinor())) { widgetToReturn = w; } } } return widgetToReturn; }

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  • Making a Delete and Reply button in Jquery

    - by Branko Ostojic
    this is my second post on the website. Of all other sites i tried, this one gave the most accurate and useful information! I'm in a bit of a trouble with buttons, i have a task to make an inbox and to add a "reply" and "delete" button into every instance of the message. I was indeed wandering if there is a better way to do that than forcing the HTML code into the script, because every message is dynamically generated. Any help and/or suggestions would be very appreciated!(The objects are called from a JSON file). $(document).ready(function(){ $.getJSON('public/js/data.json', function(json){ $.each(json.data, function(i, data){ var output = ''; if(data.from.id != '234' && data.from.name != 'Alan Ford'){ $("#inbox").append( output += '<div class="post">'+ '<div class="h1">'+data.from.name+' - '+data.subject+'</div>'+ //this gives the name of the person who sent the message and the subject '<div class="content">'+data.message_formatted+'</div>'+ //The content of the message //buttons should be squeezed left of the date //this gives the date of the message sent '<div class="time">'+data.date_sent_formatted.formatted+'</div>'+ '</div>' ); }}); }); }); var date_sent=convertToDateTime(); function delete_message(id){ console.log('Delete message with id: '+id); } function reply_message(id, sender){ console.log('Message id: '+id); console.log('Reply to: '+sender); } The complete code in the JSFiddle . Just copy/pasted!

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  • Determining if object is visible and clickable

    - by Alan Mendelevich
    I'm looking for ways to effectively determine if a control is actually visible and clickable. I mean beyond checking Visibility property of the object. I can check RenderSize and that would be [0,0] if any of the parent elements is collapsed. So this is simple too. I can also traverse up the visual tree and see if Opacity of all elements is set to 1. What I don't know how to check nicely are these scenarios: The object is obstructed by some other object. Obviously it's possible to use FindElementsInHostCoordinates() and do computations to find out how much these objects obstruct but this could be an overkill. I can also make a "screenshot" of the object in question and "screenshot" of the whole page and check if pixels where my object should be match the actual object pixels. That sounds like an overkill too. The object is obstructed by a transparent object that still "swallows" clicks (taps). The workarounds for the first problem could still fail in this scenario. Any better ideas? Do I miss something? Thanks!

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  • Do I need a spatial index in my database?

    - by Sanoj
    I am designing an application that needs to save geometric shapes in a database. I haven't choosen the database management system yet. In my application, all database queries will have an bounding box as input, and as output I want all shapes within that database. I know that databases with a spatial index is used for this kind of application. But in my application there will not be any queries of type "give me objects nearby x/y" or other more complex queries that are useful in a GIS application. I am planning of having a database without a spatial index and have queries looking like: SELECT * FROM shapes WHERE x < max_x AND x > min_x AND y < max_y AND y > min_y And have an index on the columns x (double) and y (double). As long I can see, I don't really need a database with an spatial index, howsoever my application is close to that kind of applications. And even if I would like to have nearby queries, then I could create a big enough bounding box around that point. Or will this lead to poor performance? Do I really need a spatial database? And when is a spatial index needed?

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  • problem with "select new Object ... join ... where"

    - by jacob
    Hi, I'm having a problem with an HQL query Three classes ClassOne is my BusinessObject public class ClassOne { private int id; private int status; private Set<ClassTwo> classTwos; + other fields/getters/setters/constructor etc } ClassTwo is referenced in a set of ClassOne and is kind of the history of an object of ClassOne public class ClassTwo { private int id; private int oldStatus; private int newStatus; private String message; //+ getters/setters/constructor etc } ClassThree is my DTO/VO with just one classTwo (not the whole history) public class ClassThree { private int id; private int status; private ClassTwo classTwo; public ClassThree(int pId, int pStatus, ClassTwo pClassTwo) { id=pId; status=pStatus; classTwo=pClassTwo; } //+ getters/setters etc } Now I'd like to create an HQL query like this: I'd like to get all objects of ClassThree with a certain status and if it exists the newest ClassTwo with a certain newStatus. For example: I'd like to get all the DTOs (ClassThree) of ClassOne whose status is now 1, but earlier in their history it has been 2 and I'd like to have the latest ClassTwo object which has 2 as newStatus. SELECT new ClassThree(c1.id, c1.status, c2) FROM ClassOne c1 LEFT JOIN c1.classtwos c2 (...) and (...) is where I don't know what to do, I'm not even sure if it's a join / join fetch Looked around and tried quite a lot already, but no clue. Especially with the join fetch I get some Hibernate errors like org.hibernate.QueryException: query specified join fetching, but the owner of the fetched association was not present in the select list. Fetching the BusinessObject like that is no problem SELECT distinct(c1) FROM ClassOne c1 LEFT OUTER JOIN FETCH c1.classtwos c2 and I get the ClassTwos as my field. Thanks in advance, Jacob P.S.: One thing might be important, ClassTwo has no reference to ClassOne!!

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  • Is there a way to deserialize an object into "$this"?

    - by Andreas Bonini
    I'm writing a class to handle a memcached object. The idea was to create abstract class Cachable and all the cachable objects (such as User, Post, etc) would be subclasses of said class. The class offers some method such as Load() which calls the abstract function LoadFromDB() if the object is not cached, functions to refresh/invalidate the cache, etc. The main problem is in Load(); I wanted to do something similar: protected function Load($id) { $this->memcacheId = $id; $this->Connect(); $cached = $this->memcache->get(get_class($this) . ':' . $id); if($cached === false) { $this->SetLoaded(LoadFromDB($id)); UpdateCache(); } else { $this = $cached; $this->SetLoaded(true); } } Unfortunately I need $this to become $cached (the cached object); is there any way to do that? Was the "every cachable object derives from the cachable class" a bad design idea?

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