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• Singleton wrapper for Context

  - by kpdvx

  I'm considering creating a singleton wrapper for a Context so my model objects, if necessary, can open and read from a database connection. My model objects do not have access to a Context, and I'd like to avoid needing to pass a reference to a Context from object to object. I was planning to place into this singleton a reference to the Context returned by Application.getApplicationContext(). This singleton object would be initialized in my custom Application instance before anything else would need to or have a chance to use it. Can anyone think of a reason to not do this?

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• Divide people into teams for most satisfaction

  - by Jweede

  Just a curiosity question. Remember when in class groupwork the professor would divide people up into groups of a certain number (n)? Some of my professors would take a list of n people one wants to work with and n people one doesn't want to work with from each student, and then magically turn out groups of n where students would be matched up with people they prefer and avoid working with people they don't prefer. To me this algorithm sounds a lot like a Knapsack problem, but I thought I would ask around about what your approach to this sort of problem would be.

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• Doctrine2: Filtering by ManToMany Association

  - by Shroder

  I want to retrieve a collection of objects based on what they are associated to. For example, by a category. This would be a Many to Many relationship. I've been able to achieve that with MEMBER OF, however I need to pass in an array of IDs, opposed to one at a time. I see there is an "IN ()", but it seems to require a subquery, which I would like to avoid. MEMBER OF example: SELECT o FROM Entity\Object1 o WHERE 'CATEGORY_CODE' MEMBER OF o.categories (Edit) This is what I would like to do, but perhaps I'm misunderstanding how entities work in DQL: SELECT o FROM Entity\Object1 o WHERE o.categories.Id IN (id, id, id)

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• How to know if the website being scraped has changed?

  - by Lost_in_code

  I'm using PHP to scrape a website and collect some data. It's all done without using regex. I'm using php's explode() method to find particular HTML tags instead. It is possible that if the structure of the website changes (CSS, HTML), then wrong data may be collected by the scraper. So the question is - how do I know if the HTML structure has changed? How to identify this before storing any data to my database to avoid wrong data being stored.

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• Submit multiple forms as one

  - by Stephen Sarcsam Kamenar

  I have two forms on the page. To the user it looks like 1 form, and I actually wish it was one form. But the way I'm trying to reuse code and include things, I can't avoid two forms in the source code... trying to act as one. I don't want to do ajax submit, I want a normal post submit, my form handler has redirects in it. How can I submit both of these, and get values that make sense on the server side. something like $_POST['form1]['whatever'] $_POST['form2]['thing'] Maybe take all the inputs from form 2, rename all of them with a prefix, and append them to form 1? I can't find a non-messy way of doing this. I don't think I need code, just a plan. Least messy idea wins.

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• How to change the value of progressbar in C#?

  - by shekhar

  Hi, I want to add an progress bar into my C# based application. I would like to know what is the good way of updating its value at particular events? My problem is, I have single function in UI which does all the processing.This function in turn calls many more functions, creates objects, updates database, etc. (basically performs all the work) and returns values in an output file. I have access to that function only. So in this how to update the progressbar's value at the end of each step? What is the best practice for this kind of situation? What is the good way to keep UI logic and business logic seperate? I want to avoid writting progressbar related code in my library code. Please suggest some solution. Thanks and Regards,

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• OpenGL multitexture tessellation

  - by user1715296

  I have to tessellate some surface in OpenGL with rectangular textures. Let it be a single triangle for simplicity. The textures touch each other by sides, and do not overlap. That is done by setting GL_TEXTURE_WRAP_S and GL_TEXTURE_WRAP_T to GL_CLAMP_TO_BORDER and adjusting texture coords properly. Everything goes fine while GL_TEXTURE_MIN_FILTER and GL_TEXTURE_MAG_FILTER is set to GL_NEAREST, but when I want to apply GL_LINEAR filering and/or anisotropic filtering following arifact apperas: textures border pixel's alpha gradually fall to transparent, so that line of background color is visible between neighbouring textures. How can I avoid this artifact without merging multiple textures to one while linear filtering is preserved?

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• In-memory data structure that supports boolean querying

  - by sanity

  I need to store data in memory where I map one or more key strings to an object, as follows: "green", "blue" -> object1 "red", "yellow" -> object2 I need to be able to efficiently receive a list of objects, where the strings match some boolean criteria, such as: ("red" OR "green") AND NOT "blue" I'm working in Java, so the ideal solution would be an off-the-shelf Java library. I am, however, willing to implement something from scratch if necessary. Anyone have any ideas? I'd rather avoid the overhead of an in-memory database if possible, I'm hoping for something comparable in speed to a HashMap (or at least the same order of magnitude).

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• populate a treeview with xml file using c#

  - by syedsaleemss

  Im using c#.net windows form application. I have an xml file that contains nodes. I need to populate a treeview with the nodes present in the xml file. Also avoid repeated node names. For this my idea is while populating the treeview, copy the node names into a list and there see if the node already exits. If it already exits, go to the next node else display it. List listOfNodes = new List(); listOfNodes.Add(xNode.Name.ToString()); //if (!(listOfNodes.Contains(xNode.Name.ToString()))) I was trying with this. but Im unable to do. Please suggest me with a proper code.

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• Is it bad practice to initialize a variable to a dummy value?

  - by froadie

  This question is a result of the answers to this question that I just asked. It was claimed that this code is "ugly" because it initializes a variable to a value that will never be read: String tempName = null; try{ tempName = buildFileName(); } catch(Exception e){ ... System.exit(1); } FILE_NAME = tempName; Is this indeed bad practice? Should one avoid initializing variables to dummy values that will never actually be used? (EDIT - And what about initializing a String variable to "" before a loop that will concatenate values to the String...? Or is this in a separate category? e.g. String whatever = ""; for(String str : someCollection){ whatever += str; } )

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• Zend disableLayout() leaves html & body tags in output

  - by sunwukung

  Hi all, could anyone take a look at this for me? Problem: trying to output a csv on demand using Zend Framework. I want to avoid creating files on the system so I'm trying to use the same solution posted here: http://stackoverflow.com/questions/1136264/export-csv-in-zend-framework However - I'm still getting html and body tags in the csv. I'm setting layouts in the ini file. I've tried putting the csv call earlier in the request cycle using preDispatch etc - but to no avail. Any help is greatly appreciated SWK

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• How to relate keywords to records - Many to Many

  - by webworm

  Hi All, I am looking for suggestions on database design for a sample jobs listing application. I have many jobs that I would like to associate various keywords with. Each job can have multiple keywords. I would like to store the keywords in a seperate table instead of in a field within the Job table so as to avoid mispellings in keywords. What is the best way to relate keywords to the jobs? I was thinking of using an intermediary table that would have a many to many relationship linking keywords to jobs. Is this the best way to go or should I just have a field in the Job table that contains multiple keywords? Thanks for any suggestions.

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• How can I double-enhance a class with cglib?

  - by artemb

  Hi there! Here's the code: Patient patient = factory.createPatient(); Enhancer enhancer = new Enhancer(); enhancer.setSuperclass(patient.getClass()); enhancer.setCallback(new DefaultMethodInterceptor(patient)); patient = (Patient) enhancer.create(); assertThat(patient.getFirstName()).isNotNull(); Enhancer enhancer2 = new Enhancer(); enhancer2.setSuperclass(patient.getClass()); enhancer2.setCallback(new DefaultMethodInterceptor(patient)); patient = (Patient) enhancer2.create(); assertThat(patient.getFirstName()).isNotNull(); It fails on the last assert with net.sf.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null ... Caused by: java.lang.reflect.InvocationTargetException ... Caused by: java.lang.ClassFormatError: Duplicate method name&signature in class file my/package/entity/Patient$$EnhancerByCGLIB$$ca1e6685$$EnhancerByCGLIB$$f52743be I ask this because I want to enhance Hibernate's entities, but sometimes it returns already enhanced ones by itself and my second enhancement fails. How can I avoid this?

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• Is it always bad idea to use inline css for used-once property?

  - by user93422

  I have a table, with 10 columns. I want to control the width of each column. Each column is unique, right now I create an external CSS style for each column: div#my-page table#members th.name-col { width: 40px; } I know there is a best practice to avoid inline style. I do approve using external CSS for anything look'n'feel related: fonts, colors, images. But is it really better to use external CSS in this case? It does not incur extra maintenance cost. It is easier to produce. Cons I can think of: If you have separate designers and development team - using inline styles will force designers to modify content-file (aspx in my case). It might use more bandwidth. Anything else I've missed?

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• Is there a way to get the current UIEvent being handled?

  - by not-

  I'm working in a class that is a delegate of another class; this other class is in a third-party library that I'd like to avoid changing if at all possible. The original class is handling a -touchesEnded event, and is delegating responsibility to me, but it doesn't pass the UIEvent itself to me. Is there a way to get a handle to the current event in progress? It's a double-tap handler, and all that is passed to me is the view being touched, and the point at which the touch occurred. I want to know exactly how many touches are involved in the event. Thanks! randy

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• 1120: Why can't it access the variable?

  - by Oden

  I'm new at as3, maybe thats the reason why i don't understand, why the setInterval causes an error. <mx:Script> <![CDATA[ import flash.utils.setInterval; import mx.controls.Alert; [Bindable] public var MyInt:int = 500; setInterval(function():void{ ++MyInt; },1000); ]]> </mx:Script> I have a label where the value of MyInt gets visible, the bind works perfect, i've tested it several ways, and i i create a button it grows the number, but if i use the setInterval function i get an error: Access of undefined property myInt. Why? What does cause this? Please explain it, so I can avoid errors like this. Thanks

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• MySQL: Query to obtain recipes using all given ingredients.

  - by John_A

  hi I have the following simplified tables: CREATE TABLE recipe(id int, name varchar(25)); CREATE TABLE ingredient(name varchar(25)); CREATE TABLE uses_ingredient(recipe_id int, name varchar(25)); I want to make a query that returns all id's of recipes that contain both Chicken and Cream. I have tried SELECT recipe_id FROM uses_ingredient INNER JOIN (SELECT * FROM ingredient WHERE name="Chicken" OR name="Cream") USING (name) GROUP BY recipe_id HAVING COUNT(recipe_id) >= (SELECT COUNT(*) FROM theme); which gives me :"ERROR 1248 (42000): Every derived table must have its own alias" and is probably wrong too. Next I tried SELECT recipe_id FROM (SELECT * FROM ingredient WHERE name="Chicken" OR name="Cream") AS t INNER JOIN uses_ingredient USING (name) GROUP BY recipe_id HAVING COUNT(recipe_id)>= (SELECT COUNT(*) FROM t); which gives "ERROR 1146 (42S02): Table 'recipedb.t' doesn't exist" I want to avoid creating temporary tables including using ENGINE=MEMORY.

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• Too many local variables in ASP.NET

  - by Yongwei Xing

  Hi all I wrote a control, and use a tool to do the code analysis. There is a test that I didn't pass. Avoid excessive locals, http://msdn.microsoft.com/library/ms182263(VS.90).aspx. In my CreateChildControls function, I built a big table with lots of field. I need to create a lot of TableRow and TableCell to construct the table. But these are not field or property of control. Thery are local variables in the function, which are created dynamically. Should I make these TableCells and TableRows as fields of the control? Or I just keep them as the local variables in the CreateChildControl function? Best Regards,

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• SVN always getting errors when I commit (Subclipse)

  - by jax

  I have setup svn on my server and Subclipse at home. I am the only developer and am mainly using it for the backup and versioning features. Everytime I commit my changes I get eighter: Out Of date errors or Tree conflicts Sometimes I even delete files and they don't delete on svn, in a directory hierarchy only the very last item will delete so I have to delete each folder one at a time. How do I avoid these errors in the future? Update: Another problem I am having is that sometimes eclipse seems to sync with the server so that when I refactor a filename it goes off to the server and does something and makes me wait, which is annoying. And for clarity, this is a typical operation: I might change a filename, move a file to a different folder then change the contents of a file. I select the 'Team menu' and click 'commit'. Then I get all these errors above.

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• Domain Redirection While Maintaining Original URL

  - by Steve

  I have two domains ("this_site.com" and "that_site.com") that I want to point to the same place (same set of files). BUT What I really want to do is maintain the original URL in the address bar while the visitor accesses the different pages. Example: The primary domain holding the web files is "this_site.com". If I type in "that_site.com" in the address bar, I want the address bar to keep displaying "that_site.com" no matter where they go on the web site. Normal domain redirection causes the URL displayed in the address bar to change to the 'master' domain (i.e. the visitor that typed in "that_site.com" will see the address bar's URL change to "this_site.com"). Is there some sort of .htaccess trick that I can employ to do this? What I'm trying to do is NOT confuse visitors who visit one URL and find themselves on a different URL as well as avoid the additional expense and trouble of having to maintain two separate hosting accounts.

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• Detect NativeDragDrop to Trash or RecycleBin

  - by colder

  I will let user remove item from List with a cool method. Drag an item in adobe air List control and then drop it to Trash(OSX) or Recycle Bin(Win). The trash accept move drag action only. So I think I must set dragMoveEnable=true. When I drag an item to Recycle Bin on Windows. It show accept effect(alpha mask) and Air remove that object from List's dataProvider. So I can find which one is disappear. But when I drag to Trash on MacOSX. It show effect too. But Air do nothing for List. Maybe this is a bug. How can I avoid it? Are there any way to detect where dropped by user?

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• Imposing email limits on web page

  - by Martin

  To avoid spammers, what's a good strategy for imposing limits on users when sending email from our site? A count limit per day on individual IPs? Sender emails? Domains? In general terms, but recommended figures will also be helpful. Our users can send emails through our web page. They can register and log in but are also allowed to do this without logging in, but with a captcha and with a field for the senders email. Certainly, there is a header, "The user has sent you the following message.", limiting the use for spammers, so perhaps it's not a big problem. Any comments on what I'm doing will be greatly appreciated.

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• How to define an array inside a function in C?

  - by Arunav Dev

  So in my source file I have the folowin function: void update(state* old_state, state* measurement, uint32_t size) { state new_state[size]; //some function using measurement and old_state and returning the result in newstate arm_fadd_32(measurement,old_state,newstate,size); // rest of the code } Now the compiler throws an error saying that error#28:expression must have a constant value. I think it's due to the fact that even though inside the method the size local variable is not changing the compiler is expecting a constant while defining the size. I have tried the following: int const a = size; and then tried to reinitialize it says constant value is not known. I did some research in internet and it appears that there is no easier way without using malloc, which I don't want to since I am using the code for some embedded application. Is there a way to avoid this problem without really using malloc? Thanks in advance guys!

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• How to get at TCP RTT on Windows (Linux TCP_INFO) as an user

  - by FredAlkin

  I am porting a streaming TCP app from Linux to Windows. The app streams real-time audio data using a preexisting TCP protocol (so switching to UDP isn't an option). Further, I wish to avoid being "part of the problem" and requiring Administrator rights. The Linux code uses getsockopt(... ,SOL_TCP, TCP_INFO, ..) to get the RTT (round trip time) information from the TCP connection. The application level uses this to throttle the amount of data sent over the connection (apparently to balance quality with latency). Is there an equivalent to TCP_INFO on WIndows? (google tells me that Win2K and later supports "TCP Timestamps" which would provide this information, but I've yet to find a way to get at it. Thanks in advance.

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• Activity.findViewById returning null sporadically

  - by adstro

  From the crash logs that I am getting from the Android market, I can see that some of my users are getting Force Closes caused by NullPointerExceptions when my code tries to access views that are in my application. In one example, my activity makes a call to findViewById() in onCreate() after I call setContentView(). I get an NPE when I try to access the view after the call to findViewById() (still in onCreate). What has me really scratching my head is that this does not happen all of the time (in fact most of the time the code acts as I would expect), but enough to have me concerned. I could add code to always check for null and avoid the NPE, but I would like to understand what could be causing the sporadic behavior. Does anyone know what could be causing this?

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