Search Results

Search found 18534 results on 742 pages for 'global design'.

Page 660/742 | < Previous Page | 656 657 658 659 660 661 662 663 664 665 666 667  | Next Page >

  • Which articles I've should read before starting to make my custom drawn winforms app?

    - by Dmitriy Matveev
    Hello! I'm currently developing a windows forms application with a lot of user controls. Some of them are just custom drawn buttons or panels and some of them are a compositions of these buttons and panels inside of FlowLayoutPanels and TableLayoutPanels. And the window itself is also custom drawn. I don't have much experience in winforms development, but I've made a proper decomposition of proposed design into user controls and implementation is already almost finished. I've already solved many arisen problems during development by the help of the google, msdn, SO and several dirty hacks (when nothing were helping) and still experiencing some of them. There are a lot of gaps in my knowledge base, since I don't know answers to many questions like: When I should use things like double buffer, suspended layout, suspended redraw ? What should I do with the controls which shouldn't be visible at some moment ? Common performance pitfalls (I think I've fallen in in several ones) ? So I think there should be some great articles which can give some knowledge enough to avoid most common problems and improve performance and maintainability of my application. Maybe some of you can recommend a few?

    Read the article

  • Dynamically created controls and the ASP.NET page lifecycle

    - by Dirk
    I'm working on an ASP.NET project in which the vast majority of the forms are generated dynamically at run time (form definitions are stored in a DB for customizability). Therefore, I have to dynamically create and add my controls to the Page every time OnLoad fires, regardless of IsPostBack. This has been working just fine and .NET takes care of managing ViewState for these controls. protected override void OnLoad(EventArgs e) { base.OnLoad(e); RenderDynamicControls() } private void RenderDynamicControls(){ //1. call service layer to retrieve form definition //2. create and add controls to page container } I have a new requirement in which if a user clicks on a given button (this button is created at design time) the page should be re-rendered in a slightly different way. So in addition to the code that executes in OnLoad (i.e. RenderDynamicControls()), I have this code: protected void MyButton_Click(object sender, EventArgs e) { RenderDynamicControlsALittleDifferently() } private void RenderDynamicControlsALittleDifferently() (){ //1. clear all controls from the page container added in RenderDynamicControls() //2. call service layer to retrieve form definition //3. create and add controls to page container } My question is, is this really the only way to accomplish what I'm after? It seems beyond hacky to effectively render the form twice simply to respond to a button click. I gather from my research that this is simply how the page-lifecycle works in ASP.NET: Namely, that OnLoad must fire on every Postback before child events are invoked. Still, it's worthwhile to check with the SO community before having to drink the kool-aid. On a related note, once I get this feature completed, I'm planning on throwing an UpdatePanel on the page to perform the page updates via Ajax. Any code/advice that make that transition easier would be much appreciated. Thanks

    Read the article

  • Why put a DAO layer over a persistence layer (like JDO or Hibernate)

    - by Todd Owen
    Data Access Objects (DAOs) are a common design pattern, and recommended by Sun. But the earliest examples of Java DAOs interacted directly with relational databases -- they were, in essence, doing object-relational mapping (ORM). Nowadays, I see DAOs on top of mature ORM frameworks like JDO and Hibernate, and I wonder if that is really a good idea. I am developing a web service using JDO as the persistence layer, and am considering whether or not to introduce DAOs. I foresee a problem when dealing with a particular class which contains a map of other objects: public class Book { // Book description in various languages, indexed by ISO language codes private Map<String,BookDescription> descriptions; } JDO is clever enough to map this to a foreign key constraint between the "BOOKS" and "BOOKDESCRIPTIONS" tables. It transparently loads the BookDescription objects (using lazy loading, I believe), and persists them when the Book object is persisted. If I was to introduce a "data access layer" and write a class like BookDao, and encapsulate all the JDO code within this, then wouldn't this JDO's transparent loading of the child objects be circumventing the data access layer? For consistency, shouldn't all the BookDescription objects be loaded and persisted via some BookDescriptionDao object (or BookDao.loadDescription method)? Yet refactoring in that way would make manipulating the model needlessly complicated. So my question is, what's wrong with calling JDO (or Hibernate, or whatever ORM you fancy) directly in the business layer? Its syntax is already quite concise, and it is datastore-agnostic. What is the advantage, if any, of encapsulating it in Data Access Objects?

    Read the article

  • DAL Layer : EF 4.0 or Normal Data access layer with Stored Procedure

    - by Harryboy
    Hello Experts, Application : I am working on one mid-large size application which will be used as a product, we need to decide on our DAL layer. Application UI is in Silverlight and DAL layer is going to be behind service layer. We are also moving ahead with domain model, so our DB tables and domain classes are not having same structure. So patterns like Data Mapper and Repository will definitely come into picture. I need to design DAL Layer considering below mentioned factors in priority manner Speed of Development with above average performance Maintenance Future support and stability of the technology Performance Limitation : 1) As we need to strictly go ahead with microsoft, we can not use NHibernate or any other ORM except EF 4.0 2) We can use any code generation tool (Should be Open source or very cheap) but it should only generate code in .Net, so there would not be any licensing issue on per copy basis. Questions I read so many articles about EF 4.0, on outset it looks like that it is still lacking in features from NHibernate but it is considerably better then EF 1.0 So, Do you people feel that we should go ahead with EF 4.0 or we should stick to ADO .Net and use any code geneartion tool like code smith or any other you feel best Also i need to answer questions like what time it will take to port application from EF 4.0 to ADO .Net if in future we stuck up with EF 4.0 for some features or we are having serious performance issue. In reverse case if we go ahead and choose ADO .Net then what time it will take to swith to EF 4.0 Lastly..as i was going through the article i found the code only approach (with POCO classes) seems to be best suited for our requirement as switching is really easy from one technology to other. Please share your thoughts on the same and please guide on the above questions

    Read the article

  • Qt Socket blocking functions required to run in QThread where created. Any way past this?

    - by Alexander Kondratskiy
    The title is very cryptic, so here goes! I am writing a client that behaves in a very synchronous manner. Due to the design of the protocol and the server, everything has to happen sequentially (send request, wait for reply, service reply etc.), so I am using blocking sockets. Here is where Qt comes in. In my application I have a GUI thread, a command processing thread and a scripting engine thread. I create the QTcpSocket in the command processing thread, as part of my Client class. The Client class has various methods that boil down to writing to the socket, reading back a specific number of bytes, and returning a result. The problem comes when I try to directly call Client methods from the scripting engine thread. The Qt sockets randomly time out and when using a debug build of Qt, I get these warnings: QSocketNotifier: socket notifiers cannot be enabled from another thread QSocketNotifier: socket notifiers cannot be disabled from another thread Anytime I call these methods from the command processing thread (where Client was created), I do not get these problems. To simply phrase the situation: Calling blocking functions of QAbstractSocket, like waitForReadyRead(), from a thread other than the one where the socket was created (dynamically allocated), causes random behaviour and debug asserts/warnings. Anyone else experienced this? Ways around it? Thanks in advance.

    Read the article

  • Issue Implementing Colorbox Correctly in IE (all versions)

    - by Andrew
    I've been pulling my hair out (and going way over allotted hours) to try and figure out why Colorbox isn't working properly on the following page: http://www.fiberforge.com I've set up a Colorbox test link on the very bottom right that says "Web Design By All Web Cafe", which should open up a small logo image. In Firefox, Safari, etc the modal behaves as it should, opening center center above all of the existing on-page content. In IE, not only is the modal not centered, but it appears as though it's not obeying absolute positioning and pushing all of the existing on-page content down below. Add to that the fact that it's not opening to the correct size and creating scrollbars next to the modal image, and we have ourselves one ugly modal. The scrollbars I can live with (by just resizing the min-height of the modal), but I can't figure out why it won't center. Let me say that I did not code this site initially and it was completed quite a few years ago, so there are quite probably numerous CSS hacks to get things to display properly, any number of which may be causing this problem. By contrast, Thickbox is also set up on this site (if you click on the "Play Video" callout in the dark blue area) and behaves correctly, though suffers from some weird sizing/padding issues, hence the desire to replace it with something a bit more modern and extensible. I can verify that there is no conflict having both of these modal scripts/CSS files concurrently as the problem still occurs with Colorbox even when Thickbox is removed entirely. Any thoughts or suggestions would be greatly appreciated.

    Read the article

  • passive view and display logic

    - by genesys
    Hi! In MVC and MVP and similar patterns there's often the approach of the "passive view" which is as stupid as possible. This should facilitate unit testing and create a clearer separation of view and model. I know that those patterns come in very different flavours and especially the understanding of MVP seems to differ from article to article. Therefore my question is not "how do i implement this pattern correctly". I want to improve view and model separation and go for better testability of the application. Therefore i'd like to go for a passive view. But my question is, where would you put logic that is clearly only view related? like a textviewer should scroll the text when the scrollbar is moved. would you put the logic for this into the Presenter? Let's say the textviewer has some extended functionality. like setting markings on textpassages. The logic for this makes clearly sense to be put into the Presenter. However, if it is mixed with all the 'direct' logic of the view (like scrolling the text) the Presenter could become very big, which is also not really a nice design. So my question is where to put display related logic of a passive view and what functionallity to mix in the Presenter. Thanks!

    Read the article

  • GUI for generating XML

    - by Kenston
    Hello. Does anybody know of GUIs for generating XMLs? This means the user will not be presented with an IDE with support for XML for him to type XML codes. This would be helpful for non-technical people using the system. I know this sounds easy, given many libraries that can help in generating XMLs. The issue here is that the schema is really that flexible rather than being straightforward like representing books in a library with their properties. Imagine HTML, where we can create font tags inside a body, a table, a div, or nested even within itself. The solution is a WYSIWYG application that allows user to generate html codes (XML). However, that is good for XML applied in webpages since they involve visual aspect and design. My application of XML would focus on representing some conceptual and computational definitions, much like sql-like syntax, but more than that. I'm actually after the approach or previous works done or tried, although having a library/working framework for that would be better. Btw, I'm using Java for this project. Currently, I'm just thinking of presenting element tags where user will be able to drag and drop them and nest them with each other. And perhaps, assist them through a forms in inputing values for XML attributes. I'm still hoping if there are better ideas from the community. Thank you.

    Read the article

  • Force an ASP.NET 3.5 WebSite to use version 1.0.61025.0 of System.Web.Extensions

    - by Greg
    I just upgraded my Web Site project from 2.0 to 3.5 to take advantage of the TimeZoneInfo class. When I did this, I started getting an ambiguous assembly error (*see below). The problem is, I'm not using ScriptManager, an old version of SyncFusion is. I can't upgrade SyncFusion right now, so I need to tell ASP.NET to use version 1.0.61025.0 of the assembly. I ripped out all of the 3.5 script stuff from the web.config and adding bindingRedirects to it, but it didn't work. <runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> <dependentAssembly> <assemblyIdentity name="System.Web.Extensions" publicKeyToken="31bf3856ad364e35" /> <bindingRedirect oldVersion="3.5.0.0" newVersion="1.0.61025.0" /> </dependentAssembly> <dependentAssembly> <assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35" /> <bindingRedirect oldVersion="3.5.0.0" newVersion="1.0.61025.0" /> </dependentAssembly> </assemblyBinding> </runtime> The type 'System.Web.UI.ScriptManager' is ambiguous: it could come from assembly 'C:\inetpub\wwwroot\xxx\bin\System.Web.Extensions.DLL' or from assembly 'C:\WINDOWS\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll'. Please specify the assembly explicitly in the type name.

    Read the article

  • Rhino ServiceBus: Sagas with multiple messages

    - by illdev
    I have a saga that can handle multiple messages like so: public class OrderSaga : ISaga<Order> , InitiatedBy<StartOrderSaga> , Orchestrates<CancelOrder> , Orchestrates<PaymentForOrderReceived> , Orchestrates<CheckOrderWasPaid> , Orchestrates<OrderAbandoned> , Orchestrates<CheckOrderHasBeenShipped> , Orchestrates<OrderShipped> , Orchestrates<CheckOrderHasDelayDuringShipment> , Orchestrates<OrderArrivedAtDestination> , Orchestrates<OrderCompleted> {...} but only Orchestrates<CancelOrder seems to be picked up. So I suppose (I did not find the line, but am under a strong impression this is so), that only the first Orchestrates is registered. Probably this is by design. From what I imagined a saga to be, it seems only logical that it receives many different messages, but I might be wrong. I might be wrong with my whole assumption, too :) How am I supposed to handle this? Are Sagas supposed to only handle one (in my case) a ChangeStateMessage<State or should I wire the other ConsumerOfs/Orchestrates by hand?

    Read the article

  • Why should I use Entity Framework over Linq2SQL ...

    - by Refracted Paladin
    To be clear, I am not asking for a side by side comparision which has already been asked Ad Nauseum here on SO. I am also Not asking if Linq2Sql is dead as I don't care. What I am asking is this.... I am building internal apps only for a non-profit organization. I am the only developer on staff. We ALWAYS use SQL Server as our Database backend. I design and build the Databases as well. I have used L2S successfully a couple of times already. Taking all this into consideration can someone offer me a compelling reason to use EF instead of L2S? I was at Code Camp this weekend and after an hour long demonstration on EF, all of which I could have done in L2S, I asked this same question. The speakers answer was, "L2S is dead..." Very well then! NOT! (see here) I understand EF is what MS WANTS us to use in the future(see here) and that it offers many more customization options. What I can't figure out is if any of that should, or does, matter for me in this environment. One particular issue we have here is that I inherited the Core App which was built on 4 different SQL Data bases. L2S has great difficulty with this but when I asked the aforementioned speaker if EF would help me in this regard he said "No!"

    Read the article

  • Good mobile oriented GWT widget library alternatives

    - by Michael Donohue
    I've been developing a travel planning site - tripgrep.com - which is built on appengine, GWT and smartgwt, among other technologies. It is still early days, and the site is now working well on my development environment, which is either a windows or mac computer. However, I am frequently talking up the website to my friends when we are at a bar or other venue, so I am standing there while they try to access the site via an iPhone, Android or Blackberry - I've witnessed all three. It has been painfully obvious that the browser based frontend takes a long time to download on a mobile device. I am pretty sure this is because of the javascript download for SmartGWT. So, I would like to look at alternatives to SmartGWT. What I like about SmartGWT is that it has a reasonable look and feel out of the box - I don't need to learn any design or css and it has an office application look. This is considerably better than the GWT built-in widgets, which just get a blue border. The better look-and-feel is why I went with SmartGWT early on. However, the slow load times are killing me on these mobile demos. So now I want a fast loading widget alternative that has good look-and-feel out of the box. The features I care about are: tabs, good form layout, Google maps API integration, grid data viewing. If those are all available in a library that loads quickly on a mobile device, then that's the library I want.

    Read the article

  • How to lazy load scripts in YUI that accompany ajax html fragments

    - by Chris Beck
    I have a web app with Tabs for Messages and Contacts (think gmail). Each Tab has a Y.on('click') event listener that retrieves an HTML fragment via Y.io() and renders the fragment via node.setContent(). However, the Contact Tab also requires contact.js to enable an Edit button in the fragment. How do I defer the cost of loading contact.js until the user clicks on the Contacts tab? How should contact.js add it's listener to the Edit button? The Complete function of my Tab's on('click') event could serialize Get.script('contact.js') after Y.io('fragment'). However, for better performance, I would prefer to download the script in parallel to downloading the HTML fragment. In that case, I would need to defer adding an event listener to the Edit button until the Edit button is available. This seems like a common RIA design pattern. What is the best way to implement this with YUI? How should I get the script? How should I defer sections of the script until elements in the fragment are available in the DOM?

    Read the article

  • How to configure database connection securely

    - by chiccodoro
    Similar but not the same: How to securely store database connection details Securely connecting to database within a application Hi all, I have a C# WinForms application connecting to a database server. The database connection string, including a generic user/pass, is placed in a NHibernate configuration file, which lies in the same directory as the exe file. Now I have this issue: The user that runs the application should not get to know the username/password of the general database user because I don't want him to rummage around in the database directly. Alternatively I could hardcode the connection string, which is bad because the administrator must be able to change it if the database is moved or if he wants to switch between dev/test/prod environments. So long I've found three possibilities: The first referenced question was generally answered by making the file only readable for the user that runs the application. But that's not not enough in my case (the user running the application is a person. The database user/pass are general and shouldn't even be accessible by the person.) The first answer additionally proposed to encrypt the connection data before writing it to the file. With this approach, the administrator is not able anymore to configure the connection string because he cannot encrypt it by hand. The second referenced question provides an approach for this very scenario but it seems very complicated. My questions to you: This is a very general issue, so isn't there any general "how-to-do-it" way, somehow a "design pattern"? Is there some support in .NET's config infrastructure? (optional, maybe out of scope) Can I combine that easily with the NHibernate configuration mechanism?

    Read the article

  • I have two choices of Master's classes this fall. Which is the most useful?

    - by ahplummer
    (For background purposes and context): I am a Software Engineer, and manage other Software Engineers currently. I kind of wear two hats right now: one of a programmer, and one as a 'team lead'. In this regard, I've started going back to school to get my Master's degree with an emphasis in Computer Science. I already have a Bachelor's in Computer Science, and have been working in the field for about 13 years. Our primary development environment is a Windows environment, writing in .NET, Delphi, and SQL Server. Choice #1: CST 798 DATA VISUALIZATION Course Description: Basically, this is a course on the "Processing" language: http://processing.org/ Choice #2: CST 711 INFORMATICS Course Description: (From catalog): Informatics is the science of the use and processing of data, information, and knowledge. This course covers a variety of applied issues from information technology, information management at a variety of levels, ranging from simple data entry, to the creation, design and implementation of new information systems, to the development of models. Topics include basic information representation, processing, searching, and organization, evaluation and analysis of information, Internet-based information access tools, ethics and economics of information sharing.

    Read the article

  • Java method keyword "final" and its use

    - by Lukas Eder
    When I create complex type hierarchies (several levels, several types per level), I like to use the final keyword on methods implementing some interface declaration. An example: interface Garble { int zork(); } interface Gnarf extends Garble { /** * This is the same as calling {@link #zblah(0)} */ int zblah(); int zblah(int defaultZblah); } And then abstract class AbstractGarble implements Garble { @Override public final int zork() { ... } } abstract class AbstractGnarf extends AbstractGarble implements Gnarf { // Here I absolutely want to fix the default behaviour of zblah // No Gnarf shouldn't be allowed to set 1 as the default, for instance @Override public final int zblah() { return zblah(0); } // This method is not implemented here, but in a subclass @Override public abstract int zblah(int defaultZblah); } I do this for several reasons: It helps me develop the type hierarchy. When I add a class to the hierarchy, it is very clear, what methods I have to implement, and what methods I may not override (in case I forgot the details about the hierarchy) I think overriding concrete stuff is bad according to design principles and patterns, such as the template method pattern. I don't want other developers or my users do it. So the final keyword works perfectly for me. My question is: Why is it used so rarely in the wild? Can you show me some examples / reasons where final (in a similar case to mine) would be very bad?

    Read the article

  • How do I bind an iTunes style source list to an NSTableView using Core Data?

    - by Austin
    I have an iTunes style interface in my application: Source list (NSOutlineView) on the left that contains different libraries and playlists with an NSTableView on the right side of the interface displaying information for "Presentations". Similar to iTunes, I am showing the same type of information in the table view whether a library or playlist is selected (title, author, date created, etc). I currently have an NSArrayController connected to my NSTableView and was setting the fetch predicate based on what was selected in the source list. This works fine when selecting a library because I can just set the fetch predicate to filter by the "type" field in my Presentation Core Data entity. When I try to adjust the fetch predicate for the playlist however, it doesn't look like there is any way to set the fetch predicate because I've got a table in between Playlists and Presentations to keep up with the order within the Playlist. According to the Apple docs, these type of predicates are not doable with Core Data (it basically doesn't multiple inner joins). Below is the relevant portion of my Data Model. Is my data model setup incorrectly? Should I drop the NSArrayController and handle connecting the NSTableView up by hand? I'm trying to figure out if there is a simple fix, or really a design flaw.

    Read the article

  • Best practices for managing updating a database with a complex set of changes

    - by Sarge
    I am writing an application where I have some publicly available information in a database which I want the users to be able to edit. The information is not textual like a wiki but is similar in concept because the edits bring the public information increasingly closer to the truth. The changes will affect multiple tables and the update needs to be automatically checked before affecting the public tables. I'm working on the design and I'm wondering if there are any best practices that might help with some particular issues. I want to provide undo capability. I want to show the user the combined result of all their changes. When the user says they're done, I need to check the underlying public data to make sure it hasn't been changed by somebody else. My current plan is to have the user work in a set of tables setup to be a private working area. Once they're ready they can kick off a process to check everything and update the public tables. Undo can be recorded using Command pattern saving to a table. Are there any techniques I might have missed or useful papers or patterns? Thanks in advance!

    Read the article

  • Absolutely positioned div on right causing scrollbar when the left doesn't

    - by Michael Snyder
    I'm trying to "flank" a centered div with some design elements that are absolutely positioned outside the main div's width. I'm getting a scroll bar due to the element on the right, but not the element on the left (IE6/7/8, Chrome, Firefox). How can I get rid of that horizontal scrollbar? <html> <head> <style type="text/css"> html, body { height: 100%; width: 100%; margin: 0; } body { text-align: center; } .wrapper { margin: 0 auto; position: relative; width: 960px; z-index: 0; } .main { background: #900; height: 700px; } .right, .left { position: absolute; height: 100px; width: 100px; } .right { background: #090; top: 0px; left: 960px; z-index: 1; } .left { background: #009; top: 0px; left: -100px; z-index: 1; } </style> </head> <body> <div class="wrapper"> <div class="main"></div> <div class="left"></div> <div class="right"></div> </div> </body> </html>

    Read the article

  • 1 oracle schema support large reques per day , is this safe ?

    - by Hlex
    I 'm java system designer. As we have large project to do tightly, Those projects are java api without webpage. I design to create general flow engine to support all project. This idea use 1 oracle schema , having general transaction table . And others control routing table. They all nearly complete. But DBA Team concern that he is suffered to maintain very large request to 1 schema. 1 reason is if there are problem is some table. He must offline tablespace to fix. This is problem because all project will be affected. I try to convince by split data of each table to partition by project_code & "month number to delete" . Eaxmple partition: PROJ1_05 PROJ1_06 PROJ1_07 PROJ2_05 PROJ2_06 PROJ2_07 and all transaction table will store on its partition. So, If there are problem on any part of tablespace then he should offline some partition and another project with use same table should able to service Transaction per day should around 10Meg Record per day. Is this a good idea? If I must use 1 schema, what is strategy to do? Do you have any comment?

    Read the article

  • Link click does nothing after ajax switching?

    - by Neil
    An odd case I'm trying to figure out here. I'm trying to design a mailbox system, and making some of the options ajax-y. Here's the scenario: We have a page with 2 tabs, inbox and compose. Inbox is a essentially a list of links of the form mailbox.php?msg=xxx. Clicking on the inbox or compose tabs does an ajax switch. So, let's say we're on an message page: mailbox.php?msg=123 I click on "compose" - it ajax switches to a compose form. I change my mind, click on "inbox" - it goes back to a list of messages. Note, the url has not changed at this point (all has been done through ajax). I click on the same message as before. It should go back into that message. However, nothing happens! The url it should go to (mailbox.php?msg=123) IS the url showing in the address bar, but, due to the earlier ajax activity, it's showing the inbox. Thoughts on how to resolve this? And, out of curiosity, an explanation? Normally, clicking on a link that takes you to a page you're already on will reload the page. Thanks!

    Read the article

  • Is there a good way to QuickCheck Happstack.State methods?

    - by Paul Kuliniewicz
    I have a set of Happstack.State MACID methods that I want to test using QuickCheck, but I'm having trouble figuring out the most elegant way to accomplish that. The problems I'm running into are: The only way to evaluate an Ev monad computation is in the IO monad via query or update. There's no way to create a purely in-memory MACID store; this is by design. Therefore, running things in the IO monad means there are temporary files to clean up after each test. There's no way to initialize a new MACID store except with the initialValue for the state; it can't be generated via Arbitrary unless I expose an access method that replaces the state wholesale. Working around all of the above means writing methods that only use features of MonadReader or MonadState (and running the test inside Reader or State instead of Ev. This means forgoing the use of getRandom or getEventClockTime and the like inside the method definitions. The only options I can see are: Run the methods in a throw-away on-disk MACID store, cleaning up after each test and settling for starting from initialValue each time. Write the methods to have most of the code run in a MonadReader or MonadState (which is more easily testable), and rely on a small amount of non-QuickCheck-able glue around it that calls getRandom or getEventClockTime as necessary. Is there a better solution that I'm overlooking?

    Read the article

  • How is a relative JMP (x86) implemented in an Assembler?

    - by Pindatjuh
    While building my assembler for the x86 platform I encountered some problems with encoding the JMP instruction: enc inst size in bytes EB cb JMP rel8 2 E9 cw JMP rel16 4 (because of 0x66 16-bit prefix) E9 cd JMP rel32 5 ... (from my favourite x86 instruction website, http://siyobik.info/index.php?module=x86&id=147) All are relative jumps, where the size of each encoding (operation + operand) is in the third column. Now my original (and thus fault because of this) design reserved the maximum (5 bytes) space for each instruction. The operand is not yet known, because it's a jump to a yet unknown location. So I've implemented a "rewrite" mechanism, that rewrites the operands in the correct location in memory, if the location of the jump is known, and fills the rest with NOPs. This is a somewhat serious concern in tight-loops. Now my problem is with the following situation: b: XXX c: JMP a e: XXX ... XXX d: JMP b a: XXX (where XXX is any instruction, depending on the to-be assembled program) The problem is that I want the smallest possible encoding for a JMP instruction (and no NOP filling). I have to know the size of the instruction at c before I can calculate the relative distance between a and b for the operand at d. The same applies for the JMP at c: it needs to know the size of d before it can calculate the relative distance between e and a. How do existing assemblers implement this, or how would you implement this? This is what I am thinking which solves the problem: First encode all the instructions to opcodes between the JMP and it's target, and if this region contains a variable-sized opcode, use the maximum size, i.e. 5 for JMP. Then in some conditions, the JMP is oversized (because it may fit in a smaller encoding): so another pass will search for oversized JMPs, shrink them, and move all instructions ahead), and set absolute branching instructions (i.e. external CALLs) after this pass is completed. I wonder, perhaps this is an over-engineered solution, that's why I ask this question.

    Read the article

  • Designing code for a duo Website + AIR desktop App

    - by faB
    I want to use AIR to create an OFFLINE version of a "webapp" kind of website (lots of ajax, front end code). Haven't been much further than the HelloWorld example, I keep wondering: how do you design your code, to maximize code reuse between the website (say in php or Java or .Net), and the AIR app ? Can you actually re-use 100% of the front end code, provided that it is designed to account for the AIR app ? How would you go about doing that ? For example, the website makes many Ajax calls which have latency, and uses listeners. The AIR app doesn't need listeners it could run database requests synchronously, and it doesn't need to run ajax calls right? Would you write an abstraction layer for that ? So that the same calls on the AIR app will not do a xmlhttp but instead implement the server-side code with AIR; and call the listener ? So you don't have to rewrite the front end code patterns ? Does this make sense ? It's really hard to search on Google. I'm thinking there must be a good article somewhere of somebody who went through and perhaps a framework to do that ?

    Read the article

  • How large a role does subjectiveness play in programming?

    - by Bob
    I often read about the importance of readability and maintainability. Or, I read very strong opinions about which syntax features are bad or good. Or discussions about the values of certain paradigms, like OOP. Aside from that, this same question floats about in my mind whenever I read debates on SO or Meta about subjective questions. Or read questions about best practices and sometimes find myself or others disagreeing. What role does subjectiveness play within the programming realm? Sometimes I think it plays a large role. Software developers are engineers in a way, but also people. A large part of programming is dealing with code that's human readable. This is very different from Math or Physics or other disciplines with very exact and structured rules. Here the exact structure and rules are largely up in the air, changeable on a whim, and hence the amount of languages in existence. And one person may find one language very readable, and another person may find their own language the most comforting. The same with practices. One person may not like certain accepted practices. I myself find splitting classes into different files very unreadable, for instance. But, I can't say rules haven't helped in general. Certain practices have and do make life easier. And new languages have given rise to syntax and structure that make life easier. There's certainly been a progression towards code that is easier to read and maintain even given a largely diverse group of people. So maybe these things aren't as subjective as I thought. It reminds me, in a way, of UI design. Certainly it's subjective, but then there's an entire discipline involved in crafting good UI and it tends to work. Is there something non-subjective about the ideas behind maintainability, readability, and other best practices? Is there something tangible to grasp when one develops a new language or thinks of new practices?

    Read the article

< Previous Page | 656 657 658 659 660 661 662 663 664 665 666 667  | Next Page >