Search Results

Search found 9954 results on 399 pages for 'mean'.

Page 341/399 | < Previous Page | 337 338 339 340 341 342 343 344 345 346 347 348  | Next Page >

• Wasteful Ajax Page Loading

  - by Matt Dawdy

  I've started a new job, and the portion of the project I'm working has a very odd structure. Every pages is a .Net aspx page, and it loads just fine, but nothing is really done at load time. Everything is really loaded from a jquery document.onready handler. What is even more...interesting...is that the onready handler calls some ajax calls that drop entire .aspx pages into divs on the page, but first it strips out several parts of the the returned page. This is the "magic" script the previous programmer ran on all the returned html from his ajax calls: function CleanupResponseText(responseText, uniqueName) { responseText = responseText.replace("theForm.submit();", "SubmitSubForm(theForm, $(theForm).parent());"); responseText = responseText.replace(new RegExp("theForm", "g"), uniqueName); responseText = responseText.replace(new RegExp("doPostBack", "g"), "doPostBack" + uniqueName); return responseText; } He then intercepts any kind of form postback and runs his own form submission function: function SubmitSubForm(form, container) { //ShowLoading(container); $(form).ajaxSubmit( { url: $(form).attr("action"), success: function(responseText) { $(container).html(CleanupResponseText(responseText, form.id)); $("form", container).css("margin-top", "0").css("padding-top", "0"); //HideLoading(container); } } ); } Am I way offbase in thinking that this is less than optimal? I mean, how does a browser take out the html and head and other tags that don't have anything to do with what you are really trying to drop into that div? Also, he's returning things like asp:gridview controls, and the associate viewstate, which can be quite large if his dataset is big. Has anyone seen this before?

  Read the article

• Custom UIButton Memory Management in dealloc

  - by ddawber

  I am hoping to clarify the processes going on here. I have created a subclass of UIButton whose init method looks like this: - (id)initWithTitle:(NSString *)title frame:(CGRect)btnFrame { self = [UIButton buttonWithType:UIButtonTypeCustom]; [self setTitle:title forState:UIControlStateNormal]; self.frame = btnFrame; return self; } In my view controller I am creating one of these buttons and adding it as a subview: myButton = [[CustomButton alloc] initWithTitle:@"Title" frame:someFrame]; [self.view addSubview:myButton]; In the view controller's dealloc method I log the retain count of my button: - (void)dealloc { NSLog(@"RC: %d", [myButton retainCount]); //RC = 2 [super dealloc]; NSLog(@"RC: %d", [myButton retainCount]); //RC = 1 } The way I understand it, myButton is not actually retained, even though I invoked it using alloc, because in my subclass I created an autorelease button (using buttonWithType:). In dealloc, does this mean that, when dealloc is called the superview releases the button and its retain count goes down to 1? The button has not yet been autoreleased? Or do I need to get that retain count down to zero after calling [super dealloc]? Cheers.

  Read the article

• What algorithms compute directions from point A to point B on a map?

  - by A. Rex

  How do map providers (such as Google or Yahoo! Maps) suggest directions? I mean, they probably have real-world data in some form, certainly including distances but also perhaps things like driving speeds, presence of sidewalks, train schedules, etc. But suppose the data were in a simpler format, say a very large directed graph with edge weights reflecting distances. I want to be able to quickly compute directions from one arbitrary point to another. Sometimes these points will be close together (within one city) while sometimes they will be far apart (cross-country). Graph algorithms like Dijkstra's algorithm will not work because the graph is enormous. Luckily, heuristic algorithms like A* will probably work. However, our data is very structured, and perhaps some kind of tiered approach might work? (For example, store precomputed directions between certain "key" points far apart, as well as some local directions. Then directions for two far-away points will involve local directions to a key points, global directions to another key point, and then local directions again.) What algorithms are actually used in practice? PS. This question was motivated by finding quirks in online mapping directions. Contrary to the triangle inequality, sometimes Google Maps thinks that X-Z takes longer and is farther than using an intermediate point as in X-Y-Z. But maybe their walking directions optimize for another parameter, too? PPS. Here's another violation of the triangle inequality that suggests (to me) that they use some kind of tiered approach: X-Z versus X-Y-Z. The former seems to use prominent Boulevard de Sebastopol even though it's slightly out of the way. (Edit: this example doesn't work anymore, but did at the time of the original post. The one above still works as of early November 2009.)

  Read the article

• Focus-dependent text change for TextBoxes in WPF

  - by Simon

  Hey there. I'm writing an application in WPF using the MVVM-pattern and will really often use TextBoxes. I don't want to use labels for the user to know user what the text box is for, i.e. I don't want something like this: <TextBlock> Name: </TextBlock> <TextBox /> Instead, I would like the TextBox to contain its own label. Statically, you would express it like this: <TextBox>Name</TextBox> If the cursor is displayed in the textbox, i.e. the TextBox gains focus, I want the description text to disappear. If the TextBox is left empty and it loses the focus, the description text should be shown again. It's similar to the search textbox of StackOverflow or the one of Firefox. (please tell me if your not sure what I mean). One TextBox's label may change at runtime, dependending on e.g. a ComboBox's selected element or a value in my ViewModel. (It's like in Firefox's search TextBox, if you select google from the search engins' menu, the TextBox's label changes to "Google", if you select "Yahoo" its set to "Yahoo"). Thus I want to be able to bind the label's content. Consider that I may already have a Binding on the Text-Property of the TextBox. How can implement such a behaviour and make it reusable for any of my TextBox's? Code is welcome but not needed; a description of what to do is enough. Thank you in advance.

  Read the article

• Visitor Pattern can be replaced with Callback functions?

  - by getit

  Is there any significant benefit to using either technique? In case there are variations, the Visitor Pattern I mean is this: http://en.wikipedia.org/wiki/Visitor_pattern And below is an example of using a delegate to achieve the same effect (at least I think it is the same) Say there is a collection of nested elements: Schools contain Departments which contain Students Instead of using the Visitor pattern to perform something on each collection item, why not use a simple callback (Action delegate in C#) Say something like this class Department { List Students; } class School { List Departments; VisitStudents(Action<Student> actionDelegate) { foreach(var dep in this.Departments) { foreach(var stu in dep.Students) { actionDelegate(stu); } } } } School A = new School(); ...//populate collections A.Visit((student)=> { ...Do Something with student... }); *EDIT Example with delegate accepting multiple params Say I wanted to pass both the student and department, I could modify the Action definition like so: Action class School { List Departments; VisitStudents(Action<Student, Department> actionDelegate, Action<Department> d2) { foreach(var dep in this.Departments) { d2(dep); //This performs a different process. //Using Visitor pattern would avoid having to keep adding new delegates. //This looks like the main benefit so far foreach(var stu in dep.Students) { actionDelegate(stu, dep); } } } }

  Read the article

• Hundreds of custom UserControls create thousands of USER Objects

  - by Andy Blackman

  I'm creating a dashboard application that shows hundreds of "items" on a FlowLayoutPanel. Each "item" is a UserControl that is made up of 12 or labels. My app queries a database and then creates an "item" instance for each record, populating ethe labels and textboxes with data before adding it to the FlowLayoutPanel. After adding about 560 items to the panel, I noticed that the USER Objects count in my Task Manager had gone up to about 7300, which was much much larger than any other app on my machine. I did a quick spot of mental arithmetic (OK, I might have used calc.exe) and figured that 560 * 13 (12 labels plus the UserControl itself) is 7280. So that suddenly gave away where all the objects were coming from... Knowing that there is a 10,000 USER object limit before windows throws in the towel, I'm trying to figure better ways of drawing these items onto the FlowLayoutPanel. My ideas so far are as follows: 1) User-draw the "item", using graphics.DrawText and DrawImage in place of many of the labels. I'm hoping that this will mean 1 item = 1 USER Object, not 13. 2) Have 1 instance of the "item", then for each record, populate the instance and use the Control.DrawToBitmap() method to grab an image and then use that in the FlowLayoutPanel (or similar) So... Does anyone have any other suggestions ??? P.S. It's a zoomable interface, so I have already ruled out "Paging" as there is a requirement to see all items at once :( Thanks everyone.

  Read the article

• C++ polymorphism, function calls

  - by moai

  Okay, I'm pretty inexperienced as a programmer, let alone in C++, so bear with me here. What I wanted to do was to have a container class hold a parent class pointer and then use polymorphism to store a child class object. The thing is that I want to call one of the child class's functions through the parent class pointer. Here's a sort of example of what I mean in code: class SuperClass { public: int x; } class SubClass : public SuperClass { public: void function1() { x += 1; } } class Container { public: SuperClass * alpha; Container(SuperClass& beta) { alpha = beta; } } int main() { Container cont = new Container(new SubClass); } (I'm not sure that's right, I'm still really shaky on pointers. I hope it gets the point across, at least.) So, I'm not entirely sure whether I can do this or not. I have a sneaking suspicion the answer is no, but I want to be sure. If someone has another way to accomplish this sort of thing, I'd be glad to hear it.

  Read the article

• iphone viewWillAppear not firing

  - by chzk

  I've read numerous posts about people having problems with viewWillAppear when you do not create your view heirarchy JUST right. My problem is I can't figure out what that means. If I create a RootViewController and call addSubView on that controller, I would expect the added view(s) to be wired up for viewWillAppear events. Does anyone have an example of a complex programmatic view heirarchy that successfully recieves viewWillAppear events at every level? Apple Docs state: Warning: If the view belonging to a view controller is added to a view hierarchy directly, the view controller will not receive this message. If you insert or add a view to the view hierarchy, and it has a view controller, you should send the associated view controller this message directly. Failing to send the view controller this message will prevent any associated animation from being displayed. The problem is that they don't describe how to do this. What the hell does "directly" mean. How do you "indirectly" add a view. I am fairly new to Cocoa and iPhone so it would be nice if there were useful examples from Apple besides the basic Hello World crap. Any help is greatly appreciated...

  Read the article

• How to extend a jquery ui widget ? (1.7)

  - by Jide

  I would like to create a custom version of the sortable widget. I have been searching for documentation, but could not find something really accurate. The best information I found was : http://jqueryui.pbworks.com/Widget-factory. I tried : $.widget("ui.customsortable", $.extend($.ui.sortable, { _init: function() { $.widget.prototype._init.apply(this, arguments); } })); But $.widget.prototype._init is not the function I want to call I guess since it is the $.widget prototype. Then, I tried something I read here and there : var _init = $.ui.sortable.prototype._init; $.widget("ui.customsortable", $.extend($.ui.sortable, { _init: function() { _init.apply(this, arguments); }, })); But : I can't believe I have to store all methods I want to override like this, it is so ugly. It throws an error ("this.refresh is not a function"), which means the refresh method does not exist. Does that mean I would have to recreate all methods I want to override ? What's the point of extending in that case ? Am I missing something here ? Thanks for your help !

  Read the article

• ojspc always returns 0 on errors

  - by Matt McCormick

  In my Ant build.xml file, I am trying to compile JSPs using ojspc. The files are being compiled, however, the build process is still running to completion when the JSP compilation has errors. This is part of my build.xml: <java fork="true" jar="${env.ORACLE_HOME}\j2ee\home\ojspc.jar" resultproperty="result"> <jvmarg value="-Djava.compiler=NONE"/> <arg value="-extend"/> <arg value="com.orionserver.http.OrionHttpJspPage"/> <arg value="-batchMask"/> <arg value="*.jsp"/> <arg value="${target-directory}/build/target/ear/${module-dir-name}-jsp.war"/> </java> <echo level="info">Result Property: ${result}</echo> I have tried setting the property failonerror="true" but that does not change anything. I receive the following output: [java] Detected archive, now processing contents of ../build/target/ear/web-module-jsp.war... [java] Setting up temp area... [java] Expanding archive in temp area... [java] C:\DOCUME~1\MMCCOR~1\LOCALS~1\Temp\tmp12940\_web_2d_inf\_jsp\_password.java:60: cannot resolve symbol [java] symbol : variable reqvst [java] location: class _web_2d_inf._jsp._password [java] out.print(reqvst.getAttribute("test")); [java] ^ [java] 1 error [java] Creating D:\eclipse-workspace\jdw\build\..\build\target\ear\web-module-jsp.war ... [java] Removing temp area... [echo] Result Property: 0 ...(more commands) BUILD SUCCESSFUL In the password.jsp file, I intentionally introduced an error to test. How can I get the build to fail on an error? At the Ant Java page, I am confused by: By default the return code of a is ignored. Alternatively, you can set resultproperty to the name of a property and have it assigned to the result code (barring immutability, of course). When you set failonerror="true", the only possible value for resultproperty is 0. Any non-zero response is treated as an error and would mean the build exits.

  Read the article

• Where are the network boundaries in the Java Connector Architecture (JCA)?

  - by Laird Nelson

  I am writing a JCA resource adapter. I'm also, as I go, trying to fully understand the connection management portion of the JCA specification. As a thought experiment, pretend that the only client of this adapter will be a Swing Java Application Client located on a different machine. Also assume that the resource adapter will communicate with its "enterprise information system" (EIS) over the network as well. As I understand the JCA specification, the .rar file is deployed to the application server. The application server creates the .rar file's implementation of the ManagedConnectionFactory interface. It then asks it to produce a connection factory, which is the opaque object that is deployed to JNDI for the user to use to obtain a connection to the resource. (In the case of JDBC, the connection factory is a javax.sql.DataSource.) It is a requirement that the connection factory retain a reference to the application-server-supplied ConnectionManager, which, in turn, is required to be Serializable. This makes sense--in order for the connection factory to be stored in JNDI, it must be serializable, and in order for it to keep a reference to the ConnectionManager, the ConnectionManager must also be serializable. So fine, this little object graph gets installed in the application client's JNDI tree. This is where I start to get queasy. Is the ConnectionManager--the piece supplied by the application server that is supposed to handle connection management, sharing, pooling, etc.--wholly present on the client at this point? One of its jobs is to create ManagedConnection instances, and a ManagedConnection is not required to be Serializable, and the user connection handles it vends are also not required to be Serializable. That suggests to me that the whole connection pooling machinery is shipped wholesale to the application client and stuffed into its JNDI tree. Does this all mean that JCA interactions from the client side bypass the server-side componentry of the application server? Where are the network boundaries in the JCA API?

  Read the article

• Is there "good" PRNG generating values without hidden state?

  - by actual

  I need some good pseudo random number generator that can be computed like a pure function from its previous output without any state hiding. Under "good" I mean: I must be able to parametrize generator in such way that running it for 2^n iterations with any parameters should cover all or almost all values between 0 and 2^n - 1, where n is the number of bits in output value. Combined generator output of n + p bits must cover all or almost all values between 0 and 2^(n + p) - 1 if I run it for 2^n iterations for every possible combination of its parameters, where p is the number of bits in parameters. For example, LCG can be computed like a pure function and it can meet first condition, but it can not meet second one. Say, we have 32-bit generator, m = 2^32 and it is constant, our p = 64 (two 32-bit parameters a and c), n + p = 96, so we must peek data by three ints from output to meet second condition. Unfortunately, condition can not be meet because of strictly alternating sequence of odd and even ints in output. To overcome this, hidden state must be introduced, but that makes function not pure and breaks first condition (period become much longer). Am I wanting too much?

  Read the article

• Best method to search hierarchical data

  - by WDuffy

  I'm looking at building a facility which allows querying for data with hierarchical filtering. I have a few ideas how I'm going to go about it but was wondering if there are any recommendations or suggestions that might be more efficient. As an example imagine that a user is searching for a job. The job areas would be as follows. 1: Scotland 2: --- West Central 3: ------ Glasgow 4: ------ Etc 5: --- North East 6: ------ Ayrshire 7: ------ Etc A user can search specific (i.e. Glasgow) or in a larger area (i.e. Scotland). The two approaches I am considering are: keep a note of children in the database for each record (i.e. cat 1 would have 2, 3, 4 in its children field) and query against that record with a SELECT * FROM Jobs WHERE Category IN Areas.childrenField. Use a recursive function to find all results who have a relation to the selected area. The problems I see from both are: Holding this data in the db will mean having to keep track of all changes to structure. Recursion is slow and inefficent. Any ideas, suggestion or recommendations on the best approach? I'm using C# ASP.NET with MSSQL 2005 DB.

  Read the article

• How I May Have Taken A Wrong Path in Programming

  - by Ygam

  I am in a major stump right now. I am a BSIT graduate, but I only started actual programming less than a year ago. I observed that I have the following attitude in programming: I tend to be more of a purist, scorning unelegant approaches to solving problems using code I tend to look at anything in a large scale, planning everything before I start coding, either in simple flowcharts or complex UML charts I have a really strong impulse on refactoring my code, even if I miss deadlines or prolong development times I am obsessed with good directory structures, file naming conventions, class, method, and variable naming conventions I tend to always want to study something new, even, as I said, at the cost of missing deadlines I tend to see software development as something to engineer, to architect; that is, seeing how things relate to each other and how blocks of code can interact (I am a huge fan of loose coupling) i.e the OOP thinking I tend to combine OOP and procedural coding whenever I see fit I want my code to execute fast (thus the elegant approaches and refactoring) This bothers me because I see my colleagues doing much better the other way around (aside from the fact that they started programming since our first year in college). By the other way around I mean, they fire up coding, gets the job done much faster because they don't have to really look at how clean their codes are or how elegant their algorithms are, they don't bother with OOP however big their projects are, they mostly use web APIs, piece them together and voila! Working code! CLients are happy, they get paid fast, at the expense of a really unmaintainable or hard-to-read code that lacks structure and conventions, or slow executions of certain actions (which the common reasoning against would be that internet connections are much faster these days, hardware is more powerful). The excuse I often receive is clients don't care about how you write the code, but they do care about how long you deliver it. If it works then all is good. Now, did my "purist" approach to programming may have been the wrong way to start programming? Should I just dump these purist concepts and just code the hell up because I have seen it: clients don't really care how beautifully coded it is?

  Read the article

• Field Members vs Method Variables?

  - by Braveyard

  Recently I've been thinking about performance difference between class field members and method variables. What exactly I mean is in the example below : Lets say we have a DataContext object for Linq2SQL class DataLayer { ProductDataContext context = new ProductDataContext(); public IQueryable<Product> GetData() { return context.Where(t=>t.ProductId == 2); } } In the example above, context will be stored in heap and the GetData method variables will be removed from Stack after Method is executed. So lets examine the following example to make a distinction : class DataLayer { public IQueryable<Product> GetData() { ProductDataContext context = new ProductDataContext(); return context.Where(t=>t.ProductId == 2); } } (*1) So okay first thing we know is if we define ProductDataContext instance as a field, we can reach it everywhere in the class which means we don't have to create same object instance all the time. But lets say we are talking about Asp.NET and once the users press submit button the post data is sent to the server and the events are executed and the posted data stored in a database via the method above so it is probable that the same user can send different data after one another.If I know correctly after the page is executed, the finalizers come into play and clear things from memory (from heap) and that means we lose our instance variables from memory as well and after another post, DataContext should be created once again for the new page cycle. So it seems the only benefit of declaring it publicly to the whole class is the just number one text above. Or is there something other? Thanks in advance... (If I told something incorrect please fix me.. )

  Read the article

• nHibernate storage of an object with self referencing many children and many parents

  - by AdamC

  I have an object called MyItem that references children in the same item. How do I set up an nhibernate mapping file to store this item. public class MyItem { public virtual string Id {get;set;} public virtual string Name {get;set;} public virtual string Version {get;set;} public virtual IList<MyItem> Children {get;set;} } So roughly the hbm.xml would be: <class name="MyItem" table="tb_myitem"> <id name="Id" column="id" type="String" length="32"> <generator class="uuid.hex" /> </id> <property name="Name" column="name" /> <property name="Version" column="version" /> <bag name="Children" cascade="all-delete-orphan" lazy="false"> <key column="children_id" /> <one-to-many class="MyItem" not-found="ignore"/> </bag> </class> This wouldn't work I don't think. Perhaps I need to create another class, say MyItemChildren and use that as the Children member and then do the mapping in that class? This would mean having two tables. One table holds the MyItem and the other table holds references from my item. NOTE: A child item could have many parents.

  Read the article

• What are major differences between C# and Java?

  - by enba

  I just want to clarify one thing. This is not a question on which one is better, that part I leave to someone else to discuss. I don't care about it. I've been asked this question on my job interview and I thought it might be useful to learn a bit more. These are the ones I could come up with: Java is "platform independent". Well nowadays you could say there is the Mono project so C# could be considered too but I believe it is a bit exaggerating. Why? Well, when a new release of Java is done it is simultaneously available on all platforms it supports, on the other hand how many features of C# 3.0 are still missing in the Mono implementation? Or is it really CLR vs. JRE that we should compare here? Java doesn't support events and delegates. As far as I know. In Java all methods are virtual Development tools: I believe there isn't such a tool yet as Visual Studio. Especially if you've worked with team editions you'll know what I mean. Please add others you think are relevant. Update: Just popped up my mind, Java doesn't have something like custom attributes on classes, methods etc. Or does it?

  Read the article

• Should we retire the term "Context"?

  - by MrGumbe

  I'm not sure if there is a more abused term in the world of programming than "Context." A word that has a very clear meaning in the English language has somehow morphed into a hot mess in software development, where the definition where the connotation can be completely different based on what library you happen to be developing in. Tomcat uses the word context to mean the configuration of a web application. Java applets, on the other hand, use an AppletContext to define attributes of the browser and HTML tag that launched it, but the BeanContext is defined as a container. ASP.NET uses the HttpContext object as a grab bag of state - containing information about the current request / response, session, user, server, and application objects. Context Oriented Programming defines the term as "Any information which is computationally accessible may form part of the context upon which behavioral variations depend," which I translate as "anything in the world." The innards of the Windows OS uses the CONTEXT structure to define properties about the hardware environment. The .NET installation classes, however, use the InstallContext property to represent the command line arguments entered to the installation class. The above doesn't even touch how all of us non-framework developers have used the term. I've seen plenty of developers fall into the subconscious trap of "I can't think of anything else to call this class, so I'll name it 'WidgetContext.'" Do you all agree that before naming our class a "Context," we may want to first consider some more descriptive terms? "Environment", "Configuraton", and "ExecutionState" come readily to mind.

  Read the article

• How do i set the Transaction Isolation in EJB?

  - by Nitesh Panchal

  Hello, I am not able to find a way to set TransactionIsolation in ejb. Can anybody tell me how do i set it? I am using persistence. I have looked the following classes : EntityManager , EntityManagerFactory, UserTransaction. None of them seems to have any method like setTransactionIsolation or such. Do we need to change persistence.xml? I just read a book named Mastering EJB 3.0 4th edition. They gave a full 10 page theory about Isolation level that this problems occur and that occurs and such things but at the end they gave this paragraph :- "As we now know, the EJB standard does not deal with isolation levels directly, and rightly so. EJB is a component specification. It defines the behavior and contracts of a business component with clients and middleware infrastructure (containers) such that the component can be rendered as various middleware services properly. EJBs therefore are transactional components that interact with resource managers, such as the JDBC resource manager or JMS resource manager, via JTS, as part of a transaction. They are not, hence, resource components in themselves. Since isolation levels are very specific to the behavior and capabilities of the underlying resources, they should therefore be specified at the resource API levels. " What exactly does it mean? What is meant by resource level APIs? Please help me. If persistence has no way to set Isolation Level then why do they give such huge theory in an EJB book and make it heavy in weight unnecessarily :(

  Read the article

• LINQ to SQL Where Clause Optional Criteria

  - by RSolberg

  I am working with a LINQ to SQL query and have run into an issue where I have 4 optional fields to filter the data result on. By optional, I mean has the choice to enter a value or not. Specifically, a few text boxes that could have a value or have an empty string and a few drop down lists that could have had a value selected or maybe not... For example: using (TagsModelDataContext db = new TagsModelDataContext()) { var query = from tags in db.TagsHeaders where tags.CST.Equals(this.SelectedCust.CustCode.ToUpper()) && Utility.GetDate(DateTime.Parse(this.txtOrderDateFrom.Text)) <= tags.ORDDTE && Utility.GetDate(DateTime.Parse(this.txtOrderDateTo.Text)) >= tags.ORDDTE select tags; this.Results = query.ToADOTable(rec => new object[] { query }); } Now I need to add the following fields/filters, but only if they are supplied by the user. Product Number - Comes from another table that can be joined to TagsHeaders. PO Number - a field within the TagsHeaders table. Order Number - Similar to PO #, just different column. Product Status - If the user selected this from a drop down, need to apply selected value here. The query I already have is working great, but to complete the function, need to be able to add these 4 other items in the where clause, just don't know how!

  Read the article

• different thread accessing MemoryStream

  - by Wayne

  There's a bit of code which writes data to a MemoryStream object directly into it's data buffer by calling GetBuffer(). It also uses and updates the Position and SetLength() properties appropriately. This code works purposes 99.9999% of the time. Literally. Only every so many 100,000's of iterations it will barf. The specific problem is that the memory.Position property suddenly returns zero instead of the appropriate value. However, code was added that checks for the 0 and throws an exception which include log of the MemoryStream properties like Position and Length in a separate method. Those return the correct value. Further addition shows that when this rare condition occurs, the memory.Position only has zero inside this particular method. Okay. Obviously, this must be a threading issue. But this code is well locked. However, the nature of this software is that it's organized by "tasks" with a scheduler and so any one of several actual O/S thread may run this code at any give time--but never more than one at a time. So it's my guess that ordinarily it so happens that the same thread keeps getting used for this method and then on a rare occasion a different thread get used. Then due to compiler optimizations, the different thread never gets the correct value. It gets a "stale" value. Ordinarily in a situation like this I would apply a "volatile" keyword to the variable in question. But that (those) variables are inside the MemoryStream object. Does anyone have any other idea? Or does this mean we have to implement our own MemoryStream object? (Just like we end up having to do with practically every collection in .NET?) It's a shame to have such an awesome platform as .NET and have virtually the entire system useless as-is for seriously parallelized applications. If I'm wrong or you have other ideas, please advise. Sincerely, Wayne

  Read the article

• Sql Server problems reading columns with a foreigh key

  - by illdev

  I have a weird situation, where simple queries seem to never finish for instance SELECT top 100 ArticleID FROM Article WHERE ProductGroupID=379114 returns immediately SELECT top 1000 ArticleID FROM Article WHERE ProductGroupID=379114 never returns SELECT ArticleID FROM Article WHERE ProductGroupID=379114 never returns SELECT top 1000 ArticleID FROM Article returns immediately by 'returning' I mean 'in query analyzer the green check mark appears and it says "Query executed successfully"'. I sometimes get the rows painted to the grid in qa, but still the query goes on waiting for my client to time out - 'sometimes': SELECT ProductGroupID AS Product23_1_, ArticleID AS ArticleID1_, ArticleID AS ArticleID18_0_, Inventory_Name AS Inventory3_18_0_, Inventory_UnitOfMeasure AS Inventory4_18_0_, BusinessKey AS Business5_18_0_, Name AS Name18_0_, ServesPeople AS ServesPe7_18_0_, InStock AS InStock18_0_, Description AS Descript9_18_0_, Description2 AS Descrip10_18_0_, TechnicalData AS Technic11_18_0_, IsDiscontinued AS IsDisco12_18_0_, Release AS Release18_0_, Classifications AS Classif14_18_0_, DistributorName AS Distrib15_18_0_, DistributorProductCode AS Distrib16_18_0_, Options AS Options18_0_, IsPromoted AS IsPromoted18_0_, IsBulkyFreight AS IsBulky19_18_0_, IsBackOrderOnly AS IsBackO20_18_0_, Price AS Price18_0_, Weight AS Weight18_0_, ProductGroupID AS Product23_18_0_, ConversationID AS Convers24_18_0_, DistributorID AS Distrib25_18_0_, type AS Type18_0_ FROM Article AS articles0_ WHERE (IsDiscontinued = '0') AND (ProductGroupID = 379121) shows this behavior. I have no idea what is going on. Probably select is broken ;) Anyone can tell me how to handle such a situation? More info, anyone?

  Read the article

• JQuery: how to use "delegate" instead of "live"?

  - by JacobD

  I've read countless articles how using the JQuery delegate is much more efficient than using the "live" event. As such, I'm having trouble converting my existing Live code to using Delegate. $("#tabs li:eq(0)").live('click',function(){ //...code }); $('#A > div.listing, #B > div.listing, #C > div.listing').live('mouseover',function(){ // ...code }); When I replace the previous code with what I assume is more efficient delegate code, my page doesn't load. $("#tabs li:eq(0)").delegate('click',function(){ //...code }); $('#A > div.listing, #B > div.listing, #C > div.listing').delegate('mouseover',function(){ // ...code }); Any idea why my delegate code doesn't work? Also, any suggestions on how to make this more efficient? UPDATE: The think part of the problem is that, both "#tabs" and "#A, #B, #C" are't present on the web page at page load. Those attributes are dynamically inserted onto the page with an AJAX call. As such, does that mean I have to use live over delegate?

  Read the article

• Mixing menuItem.setIntent with onOptionsItemSelected doesn't work

  - by superjos

  While extending a sample Android activity that fires some other activities from its menu, I came to have some menu items handled within onOptionsItemSelected, and some menu items (that just fired intents) handled by calling setIntent within onCreateOptionsMenu. Basically something like: @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); menu.add(0, MENU_ID_1, Menu.NONE, R.string.menu_text_1); menu.add(0, MENU_ID_2, Menu.NONE, R.string.menu_text_2); menu.add(0, MENU_ID_3, Menu.NONE, R.string.menu_text_3). setIntent(new Intent(this, MyActivity_3.class)); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { super.onOptionsItemSelected(item); switch (item.getItemId()) { case (MENU_ID_1): // Process menu command 1 ... return true; case (MENU_ID_2): // Process menu command 2 ... // E.g. also fire Intent for MyActivity_2 return true; default: return false; } } Apparently, in this situation the Intent set on MENU_ID_3 is never fired, or anyway the related activity is never started. Android javadoc at some point goes like <<[if you set an intent on a menu item] and nothing else handles the item, then the default behavior will be to [start the activity with the intent]. What does it actually mean "and nothing else handles the item"? Is it enough to return false from onOptionsItemSelected? I also tried not to call super.onOptionsItemSelected(item) at the beginning and only invoke it in the default switch case, but I had same results. Does anyone have any suggestion? Does Android allow to mix the two type of handling? Thanks for your time everyone.

  Read the article

• Rewriting jQuery to plain old javascript - are the performance gains worth it?

  - by Swader

  Since jQuery is an incredibly easy and banal library, I've developed a rather complex project fairly quickly with it. The entire interface is jQuery based, and memory is cleaned regularly to maintain optimum performance. Everything works very well in Firefox, and exceptionally so in Chrome (other browsers are of no concern for me as this is not a commercial or publicly available product). What I'm wondering now is - since pure plain old javascript is really not a complicated language to master, would it be performance enhancing to rewrite the whole thing in plain old JS, and if so, how much of a boost would you expect to get from it? If the answers prove positive enough, I'll go ahead and do it, run a benchmark and report back with the precise findings. Cheers Edit: Thanks guys, valuable insight. The purpose was not to "re-invent the wheel" - it was just for experience and personal improvement. Just because something exists, doesn't mean you shouldn't explore it into greater detail, know how it works or try to recreate it. This is the same reason I seldom use frameworks, I would much rather use my own code and iron it out and gain massive experience doing it, than start off by using someone else's code, regardless of how ironed out it is. Anyway, won't be doing it, thanks for saving me the effort :)

  Read the article

< Previous Page | 337 338 339 340 341 342 343 344 345 346 347 348  | Next Page >