Search Results

Search found 4569 results on 183 pages for 'zeta components'.

Page 157/183 | < Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >

  • Scalability 101: How can I design a scalable web application using PHP?

    - by Legend
    I am building a web-application and have a couple of quick questions. From what I learnt, one should not worry about scalability when initially building the app and should only start worrying when the traffic increases. However, this being my first web-application, I am not quite sure if I should take an approach where I design things in an ad-hoc manner and later "fix" them. I have been reading stories about how people start off with an app that gets millions of users in a week or two. Not that I will face the same situation but I can't help but wonder, how do these people do it? Currently, I bought a shared hosting account on Lunarpages and that got me started in building and testing the application. However, I am interested in learning how to build the same application in a scalable-manner using the cloud, for instance, Amazon's EC2. From my understanding, I can see a couple of components: There is a load balancer that first receives requests and then decides where to route each request This request is then handled by a server replica that then processes the request and updates (if required) the database and sends back the response to the client If a similar request comes in, then a caching mechanism like memcached kicks into picture and returns objects from the cache A blackbox that handles database replication Specifically, I am trying to do the following: Setting up a load balancer (my homework revealed that HAProxy is one such load balancer) Setting up replication so that databases can be synchronized Using memcached Configuring Apache to work with multiple web servers Partitioning application to use Amazon EC2 and Amazon S3 (my application is something that will need great deal of storage) Finally, how can I avoid burning myself when using Amazon services? Because this is just a learning phase, I can probably do with 2-3 servers with a simple load balancer and replication but until I want to avoid paying loads of money accidentally. I am able to find resources on individual topics but am unable to find something that starts off from the big picture. Can someone please help me get started?

    Read the article

  • client-side data storage and retrieval with html and javascript

    - by pedalpete
    I'm building what I am hoping to be a fairly simple, quick and dirty demo app. So far, I've managed to build a bunch of components using only html and javascript. I know that eventually I'll hook-up a db, but at this point I'm just trying to show off some functionality. In the page, a user can select a bunch of other users (like friends). Then they go to a separate html page and there is some sorting info based on the selected users. So my first attempt was to put the selected users object into a cookie, and retrieve the cookie on the second page. Unfortunately, if the user changed their selection, the cookie wasn't getting updated, and my searches on StackOverflow seemed to say that deleting and updating cookies is unreliable. I tried function updateCookie(updatedUserList){ jQuery.cookie('userList',null); jQuery.cookie('userList',updatedUserList); } but though it set the cookie to null, it wouldn't update it on the second value. So I decided to put the selected users object into a form. Unfortunately, it looks like I can't retrieve the contents from the form on the client-side, only on the server-side. Is there another way to do this? I've worked in PHP and Rails, but I'm trying to do this quickly and simply before building it out into something larger and am trying to avoid any server-side processing for now, which I have managed to do up to this point.

    Read the article

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

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

    Read the article

  • Enterprise Platform in Python, Design Advice

    - by Jason Miesionczek
    I am starting the design of a somewhat large enterprise platform in Python, and was wondering if you guys can give me some advice as to how to organize the various components and which packages would help achieve the goals of scalability, maintainability, and reliability. The system is basically a service that collects data from various outside sources, with each outside source having its own separate application. These applications would poll a central database and get any requests that have been submitted to perform on the external source. There will be a main website and REST/SOAP API that should also have access to the central data service. My initial thought was to use Django for the web site, web service and data access layer (using its built-in ORM), and then the outside source applications can use the web service(s) to get the information they need to process the request and save the results. Using this method would allow me to have multiple instances of the service applications running on the same or different machines to balance out the load. Are there more elegant means of accomplishing this? i've heard of messaging systems such as MQ, would something like that be beneficial in this scenario? My other thought was to use a completely separate data service not based on Django, and use some kind of remoting or remote objects (in they exist in Python) to interact with the data model. The downside here would be with the website which would become much slower if it had to push all of its data requests through a second layer. I would love to hear what other developers have come up with to achieve these goals in the most flexible way possible.

    Read the article

  • Acessing a wordpress database from an iPhone App.

    - by Code
    Hi guys, I've been asked to create an app that will get data back from a database where the CMS will be Wordpress. I've never used a CMS so I'm trying to get a (overview)picture in my head of how it could all work and what each of the components would be. And what a CMS actually brings to the party. Creating the app itself is pretty clear. I've done a few already. I've made a database before and shouldnt cause a problem. But what is going to be in the middle between the app and the database? Part A: I'm guessing iphone apps typically would call some php file that's hosted on the server? The php then would make a call to the database and return the data somehow, maybe as xml. But this is really basic and wouldnt require a CMS. Just a database and a phpfile, or am I wrong? Part B: If i wanted to run a check on the database every minute to see if any of the data in database was no longer valid and remove it if needed, that would require somekind of program running on the server. So that program would be Wordpress, since it is managing the content, so a content management system is actually needed and is for these kind of taskes. Am i understanding the role of CMS? Many Thanks, -Code

    Read the article

  • smart phone UI limitations

    - by Manny
    I would like to know, what limitations there are for how far one can go in terms of replacing UI components of current touch screen smart phones, in particular iPhone, Blackberry and android based phones. What I would like to do is create a custom UI for dialing out and incoming calls. I have some experience with Blackberry development. The theme builder for it, can be used to customize certain items on the incoming call screen, but it doesn't look like that you can increase the size of answer button. I know Blackberry also gives you access to all the phone APIs, but I'm not sure that you can create your own UI that can gain preference over the Blackberry incoming call screen. And if you try to customize the incoming call screen by adding any buttons to it, they would be rendered as pictures. I could possibly design a complete UI for android, since different manufactures have different UI for android based phones. Can I do what I want to do using iPhone, Blackberry or android? Or any other phone for that matter? I am guessing may be for Nokia phones using Qt, but I prefer the 3 platforms I listed. Thanks for all your help.

    Read the article

  • Best practice- How to team-split a django project while still allowing code reusal

    - by Infinity
    I know this sounds kind of vague, but please let me explain- I'm starting work on a brand new project, it will have two main components: "ACME PRODUCT" (think Gmail, Meebo, etc), and "THE SITE" (help, information, marketing stuff, promotional landing pages, etc lots of marketing-induced cruft). So basically the url /acme/* will load stuff in the uber cool ajaxy application, and every other URI will load stuff in the other site. Problem: "THE SITE" component is out of my hands, and will be handled by a consultants team that will work closely with marketing, And I and my team will work solely on the ACME PRODUCT. Question: How to set up the django project in such a way that we can have: Seperate releases. (They can push new marketing pages and functionality without having to worry about the state of our code. Maybe even separate Subversion "projects") Minimize impact (on our product) of whatever flying-unicorns-hocus-pocus the other team codes into the site. Still allow some code reusal. My main concern is that the ACME product needs to be rock solid, and therefore needs to be somewhat isolated of whatever mistakes/code bloopers the consultants make in their marketing side of the site. How have you handled this? Any ideas? Thanks!

    Read the article

  • Adapting the width of a Flexs 3 DataGridColumn to the content of its ItemRenderer ?

    - by phtrivier
    I have the following scenario : A Flex 3 DataGrid is sitting here At runtime, a column is added to this grid The column has a custom ItemRenderer The ItemRenderer inherits from HBox, and adds a few items to the HBOx dynamically My problem is that the width of the column doesn't change. As a consequence, my column stays small, and an ugly horizontal scrollbar is displayed in the line, instead of my content (which is completely unreadable). I would like the column to adapt its width to the content of the HBox in the ItemRenderer. I tried the following : Setting the 'percentWidth' of the ItemRenderer to '100' Invalidating the properties of the ItemRenderer after adding the items The only thing that has a "visible" effect it to force the width of the DataGridColumn. Obviously this is not acceptable since I'm dynamically adding components to the ItemRenderer, and I don't know how many or how big they are. Besides, when I am in the ItemRenderer, I have no access to the column itself (or do I ?) so I cannot force the size of the column from here. So is there a way around this ? Would AdvancedDataGrid help here (notwhistanding the fact that I cannot really use it for other reasons ...) Thanks PH

    Read the article

  • Calling a WPF Appliaction and modify exposed properties?

    - by Justin
    I have a WPF Keyboard Application, it is developed in such a way that an application could call it and modify its properties to adapt the Keyboard to do what it needs to. Right now I have a file *.Keys.Set which tells the appliaction (on open) to style itself according to that new style. I know this file could be passed as a command line argument into the appliaction. That would not be a problem. My concern is, is thier a way via a managed environment to change the properties of the executable as long as they are exposed properly, an example: 'Creates a new instance of the Keyboard Appliaction Dim e_key as new WpfAppliaction("C:\egt\components\keyboard.exe") 'Sets the style path e_key.SetStylePath("c:\users\joe\apps\me\default.keys.set") e_key.Refresh() 'Applies the style e_key.HideMenu() 'Hides the menu e_key.ShowDeck("PIN") 'Shows the custom "deck" of keyboard keys the developer 'Created in the style appliaction. ''work with events and resposne 'Clear the instance from memory e_key.close e_key.dispose e_key = nothing This would allow my application to become easily accessible to other Touch Screen Application Developers, allowing them to use my key_board and keep the functionality they need. It seems like it might be possible because (name of executable).application shows all the exposed functions, properties, and values. I just have never done this before. Any help would be appreciated, thank you in advance.

    Read the article

  • cakephp isAuthorized() not being called

    - by Jack B Nimble
    I am trying to use the isAuthorized() method to do a check for an admin flag, but the function never seems to be called. Even when I set the function to always return false, it allows any user. It just seems like it isn't being called. Do I need to do something more than setting $this-Auth-authorize = 'controller' ? from /app/app_controller.php class AppController extends Controller { var $components = array('Auth'); function beforeFilter() { $this->Auth->loginAction = array('controller' => 'users', 'action' => 'login'); $this->Auth->loginRedirect = array('controller' => 'pages', 'display' => 'home'); $this->Auth->logoutRedirect = '/'; $this->Auth->authorize = 'controller'; $this->Auth->userScope = array('User.active' => 1); } function isAuthorized() { if (strpos($this->action, "admin_") != false) { if ($this->Auth->user('isAdmin') == '0') { return false; } } return true; } }

    Read the article

  • What do you call a generalized (non-GUI-related) "Model-View-Controller" architecture?

    - by dcuccia
    I am currently refactoring code that coordinates multiple hardware components for data acquisition, and feeling a bit like I'm recreating the wheel. In particular, an MVC-like pattern seems to be emerging. Except, this has nothing to do with a GUI and I'm worried that I'm forcing this particular pattern where another might be more appropriate. Here's my scenario: Individual hardware "component" classes obey interface contracts for each hardware type. Previously, component instances were orchestrated by a single monolithic InstrumentController class, which relied heavily on configuration + branching logic for executing a specific acquisition sequence. After an iteration, I have a separate controller for each component, with these controllers all managed by a small InstrumentControllerBase (or its derivatives). The composite system will receive "input" either programmatically or via inter-hardware component triggering - in either case these interactions are routed to, and handled by, the appropriate controller. So, I have something that feels MVC-esque, but I don't know if that's because I'm forcing the point. With little direct MVC experience in application development, it's hard to know if I'm just trying to make my scenario fit MVC, where another pattern might be a good alternative or complimentary. My problem is, search results and wiki documentation of these family of patterns seems to immediately drop me into GUI-specific discussions. I understand "M means Model data and the V means View" - but do you call the superset pattern? Component-Commander-Controller? Whence can I exhume examples exemplary?

    Read the article

  • Not Understanding Basics Of Dynamic DataBinding (bindPropety) In Flex

    - by Joshua
    I need to dynamically bind properties of components created at runtime. In this particular case please assume I need to use bindProperty. I don't quite understand why the following simplistic test is failing (see code). When I click the button, the label text does not change. I realize that there are simpler ways to go about this particular example using traditional non-dynamic binding, but I need to understand it in terms of using bindProperty. Can someone please help me understand what I'm missing? <?xml version="1.0" encoding="utf-8"?> <mx:WindowedApplication xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" xmlns:ns1="Tools.*" minWidth="684" minHeight="484" xmlns:ns2="*" creationComplete="Init();"> <mx:Script> <![CDATA[ import mx.collections.ArrayCollection; import mx.binding.utils.*; public var Available:ArrayCollection=new ArrayCollection(); public function get Value():String { return (Available.getItemAt(0).toString()); } public function Init():void { Available.addItemAt('Before', 0); BindingUtils.bindProperty(Lab, 'text', this, 'Value'); } public function Test():void { Available.setItemAt('After', 0); } ]]> </mx:Script> <mx:Label x="142" y="51" id="Lab"/> <mx:Button x="142" y="157" label="Button" click="Test();"/> </mx:WindowedApplication> Thanks in advance.

    Read the article

  • PHP OO vs Procedure with AJAX

    - by vener
    I currently have a AJAX heavy(almost everything) intranet webapp for a business. It is highly modularized(components and modules ala Joomla), with plenty of folders and files. ~ 80-100 different viewing pages (each very unique in it's own sense) on last count and will likely to increase in the near future. I based around the design around commands and screens, the client request a command and sends the required data and receives the data that is displayed via javascript on the screen. That said, there are generally two types of files, a display files with html, javascript, and a little php for templating. And also a php backend file with a single switch statement with actions such as, save, update and delete and maybe other function. There is very little code reuse. Recently, I have been adding an server sided undo function that requires me to reuse some code. So, I took the chance to try out OOP but I notice that some functions are so simple, that creating a class, retrieving all the data then update all the related rows on the database seems like overkill for a simple action as speed is quite critical. Also I noticed there is only one class in an entire file. So, what if the entire php is a class. So, between creating a class and methods, and using global variables and functions. Which is faster?

    Read the article

  • Automatically Organize Tags in Tax/Folksonomy

    - by Rob Wilkerson
    I'm working on a process that will perform natural language processing (NLP) on one--and potentially several--of our content rich sites. What I'd like to do once the NLP is complete is to automatically organize the output (generally a set of terms that you might think of as tags given the prevalence of that metaphor) into some kind of standard or generally accepted organizational structure. In a perfect world, I'd really like this to be crowd sourced under the folksonomy concept (as opposed to a taxonomy) since the ultimate goal is to target/appeal to real people rather than "domain experts", but I'm open to ideas and best practices. For the obvious purpose of scalability, I'd like to automate the population of this tax/folksonomy so that "some guy" in the team/organization isn't responsible for looking at a bunch of words (with or without context) and arbitrarily fleshing out the contextual components of the tree. I have a few ideas for doing this that require some research to establish viability, but I have exactly zero practical experience with this sort of thing so the ideas really just boil down to stuff I made up that might perform some role in accomplishing the task. Imagining that others have vastly more experience with this sort of thing, I'm hoping that I can stand on your shoulders. Thanks for your thoughts and insights.

    Read the article

  • How do I correctly reference georss: point in my xsd?

    - by Chris Hinch
    I am putting together an XSD schema to describe an existing GeoRSS feed, but I am stumbling trying to use the external georss.xsd to validate an element of type georss:point. I've reduced the problem to the smallest components thusly: XML: <?xml version="1.0" encoding="utf-8"?> <this> <apoint>45.256 -71.92</apoint> </this> XSD: <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:georss="http://www.georss.org/georss"> <xs:import namespace="http://www.georss.org/georss" schemaLocation="http://georss.org/xml/1.1/georss.xsd"/> <xs:element name="this"> <xs:complexType> <xs:sequence> <xs:element name="apoint" type="georss:point"/> </xs:sequence> </xs:complexType> </xs:element> </xs:schema> If I make apoint type "xs: string" instead of "georss: point", the XML validates happily against the XSD, but as soon as I reference an imported type (georss: point), my XML validator (Notepad++ | XML Tools) "cannot parse the schema". What am I doing wrong?

    Read the article

  • OpenGL Pixel Format Attributes (NSOpenGLPixelFormatAttibutes) explanation?

    - by nacho4d
    Hi, I am not new to OpenGL, but not an expert. Many tutorials teach how to draw, 3D, 2D, projections, orthogonal, etc, but How about setting a the view? (NSOpenGLView in Cocoa, Macs). For example I have this: - (id) initWithFrame: (NSRect) frame { GLuint attribs[] = { //PF: PixelAttibutes NSOpenGLPFANoRecovery, NSOpenGLPFAWindow, NSOpenGLPFAAccelerated, NSOpenGLPFADoubleBuffer, NSOpenGLPFAColorSize, 24, NSOpenGLPFAAlphaSize, 8, NSOpenGLPFADepthSize, 24, NSOpenGLPFAStencilSize, 8, NSOpenGLPFAAccumSize, 0, 0 }; NSOpenGLPixelFormat* fmt = [[NSOpenGLPixelFormat alloc] initWithAttributes: (NSOpenGLPixelFormatAttribute*) attribs]; return self = [super initWithFrame:frame pixelFormat: [fmt autorelease]]; } And I don't understand very well their usage, specially when combining them. For example: If I want my view to be capable of full screen should I write NSOpenGLPFAFullScreen only ? or both? (by capable I mean not always in full screen) Regarding Double Buffer, what is this exactly? (Below: Apple's definition) If present, this attribute indicates that only double-buffered pixel formats are considered. Otherwise, only single-buffered pixel formats are considered Regarding Color: if NSOpenGLPFAColorSize is 24 and NSOpenGLPFAColorSize is 8 then it means that alpha and RGB components are treated differently? what happen if I set the former to 32 and the later to 0? Etc, etc,In general how do I learn to set my view from scratch? Thanks in advance. Ignacio.

    Read the article

  • How do I change the application background color at run-time in a Flex 3.5 application?

    - by Adam Tuttle
    I have a Flex 3.5 application that will serve multiple purposes, and as part of the visual changes that I'd like to make to indicate which mode the application is in, I want to change its background color. Currently, the application tag looks like this: <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:com="ventures.view.component.*" xmlns:views="ventures.view.*" layout="absolute" preinitialize="onPreInitialize()" creationComplete="onCreationComplete()" applicationComplete="onApplicationComplete()" click="onClick(event)" enabled="{(!chainController.generalLocked)}" backgroundGradientColors="[0xFFFFFF, 0xFFFFFF]" > I've tried using a binding, for both the backgroundColor and backgroundGradientColors attributes: <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" ... backgroundColor="{app_background_color}" > —and— <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" ... backgroundGradientColors="{app_background_color}" > but for the former binding is not allowed, and for the latter there is a warning that: Data binding will not be able to detect assignments to "app_background_color". I also ran across this page which seems to indicate that I could do it with the setStyle() method, but the documentation seems to indicate that this method is only available for components, not the main canvas. I suppose I could wrap everything in a <mx:Canvas></mx:Canvas> specificially for this purpose, but that seems wasteful—like Div-itis in HTML or something. What's the best way to change the main application background color at run-time?

    Read the article

  • Can Delphi 5 generate a .PDB file that VS can use?

    - by Vilx-
    We've got this large application written in Delphi 5, and development is ongoing to this day. There is research going on into migrating to newer versions, but so far there is no success, as some 3rd party components have not been updated in ages and do not work on later versions. In the meantime however people need to continue work on it. Now Delphi 5 IDE is no real treat. It's pretty bug-ridden and lacks a lot of features of contemporary IDEs which makes it difficult to use. Especially when it comes to debugging. So I was wondering - would it be possible to use Visual Studio in the process? As far as I know the .PDB file format is pretty old and is well documented. Could it be possible to make the Delphi compiler to somehow generate a .PDB files for it's compiled results? Then the program could be debugged with Visual Studio, possibly to a much greater extent than in the original IDE. Well, the absolute Holy Grail would be to move all development to VS, just keeping the compiler from Delphi, but I imagine that would be pretty impossible.

    Read the article

  • Set JTabbedPane width to constant

    - by msp
    I'm implementing an UI in Java Swing. Therefore I use a JTabbedPane. The tabbedPane has no components at startup. When i add a tab to the tabbedpane, the width of the tabbedpane increases, when i remove the tab, the width resizes to the width at the startup. This should not happen. The tabbedpane is placed on a JPanel which has a gridbag layout. Layout code: Container contentPane = mainFrame.getContentPane(); contentPane.setLayout( new GridBagLayout() ); GridBagConstraints c = new GridBagConstraints(); // add the component tree initComponentTree(); c.gridx = 0; c.gridy = 0; c.gridheight = 1; c.gridwidth = 1; c.fill = GridBagConstraints.BOTH; c.anchor = GridBagConstraints.LINE_START; c.weightx = 1; c.weighty = 1; contentPane.add( componentTree, c ); // add the tabbed pane initTabbedPane(); c.gridx = 1; c.weightx = 10; contentPane.add( tabbedPane, c ); // add the status panel initStatusPanel(); c.gridx = 0; c.gridy = 1; c.gridwidth = 2; c.fill = GridBagConstraints.HORIZONTAL; c.anchor = GridBagConstraints.LINE_START; c.weightx = 0; c.weighty = 0; contentPane.add( statusPanel, c ); Hope someone can help!

    Read the article

  • Spring annotation-based container configuration context:include & exclude filters

    - by lisak
    Hey, first off I point to the similar question. I spent more than an hour to set this up, but PathMatchingResourcePatternResolver still scans everything. I have one common.xml (that is imported from specific.xml) and a specific.xml bean definition file. The context is loaded from specific.xml. In common.xml there is this element: <context:component-scan base-package="cz.instance.transl"> <context:exclude-filter type="aspectj" expression="cz.instance.transl.model..* &amp;&amp; cz.instance.transl.service..* &amp;&amp; cz.instance.transl.hooks..*"/> </context:component-scan> Where classes in packages like cz.instance.transl.service.* should not be subject of scanning, but everything else in here cz.instance.transl.* should be scanned through. But PathMatchingResourcePatternResolver marks everything as matching resources. It is the same with regex. BTW: in xml style configuration, one can have many components that share a common.xml beans via "import resource" when loading context. How this is done when Annotation-based container configuration is used ?

    Read the article

  • FLEX: how to better align my Tile component to the puppet (and how to solve roll over out effects) ?

    - by Patrick
    hi, At the moment my Puppets are larger on the left if I add them the <mx:Tile> component (with tags): http://dl.dropbox.com/u/72686/puppets.png how can I move my Tile component to the right ? In order to align with the left border of my puppets ? <mx:Tile id="tagsPopup" width="200" visible="false" > <mx:LinkButton label="Tag1" /> <mx:LinkButton label="Tag2" /> <mx:LinkButton label="Tag3" /> <mx:LinkButton label="Tag4" /> </mx:Tile> <mx:VBox verticalGap="0"> <mx:Image id="puppet" source="@Embed(source='../icons/userIcon.png')" /> <mx:Label id="username" text="Nickname" visible="false" fontWeight="bold" /> </mx:VBox> 2nd Question: I want to add objects on top of the puppets, some of them are visible only when the mouse is over, and they are overlying the ones are permanently visible. How do you suggest to implement it ? I was thinking to add in MXML all visible elements and then use Actionscript to add the fade in fade out components. However I just realize it is quite tricky, because I want the user select for example tag1, tag2 and tag3, with the mouse. Instead now they disappear when the mouse rolls out from the puppet image. Any guideline ? thanks

    Read the article

  • What is the Rule of Thumb on Exposing Encapsulated Class Methods

    - by javamonkey79
    Consider the following analogy: If we have a class: "Car" we might expect it to have an instance of "Engine" in it. As in: "The car HAS-A engine". Similarly, in the "Engine" class we would expect an instance of "Starting System" or "Cooling System" which each have their appropriate sub-components. By the nature of encapsulation, is it not true that the car "HAS-A" "radiator hose" in it as well as the engine? Therefore, is it appropriate OO to do something like this: public class Car { private Engine _engine; public Engine getEngine() { return _engine; } // is it ok to use 'convenience' methods of inner classes? // are the following 2 methods "wrong" from an OO point of view? public RadiatorHose getRadiatorHose() { return getCoolingSystem().getRadiatorHose(); } public CoolingSystem getCoolingSystem() { return _engine.getCoolingSystem(); } } public class Engine { private CoolingSystem _coolingSystem; public CoolingSystem getCoolingSystem() { return _coolingSystem; } } public class CoolingSystem { private RadiatorHose _radiatorHose; public RadiatorHose getRadiatorHose() { return _radiatorHose; } } public class RadiatorHose {//... }

    Read the article

  • Add Source file link to the default ASP.NET Server Error page?

    - by Max Schilling
    Has anyone ever thought to attempt to modify the default ASP.NET Server error page to provide a link BACK to the error source in Visual Studio? Consider the following standard error page in ASP.NET: Server Error in '/myproject' Application. Invalid object name 'usp_DoSomething'. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Data.SqlClient.SqlException: Invalid object name 'usp_DoSomething'. Source Error: Line 4323: cmd.CommandText = "usp_DoSomething"; Line 4324: Line 4325: using (var dr = cmd.ExecuteReader()) Line 4326: { Line 4327: if (dr != null) Source File: c:\development\myproject\myproject.components\providers\sql\sqldataprovider.cs Line: 4325 When an error like this is generated, the HTML has the source back to the file the error occurs in and the line number. Has anyone ever written or thought of writing some mechanism to turn the text into a link back to the error in Visual Studio? I've never seen anything that does it, but it just seems like it would be a helluva nice feature and I think about it in the back of my mind every time an error occurs when I have to manually go find it in the source. It would just be nice to be able to click a link to take me straight there. Anyone written any, or know of any solutions for this. I use Chrome or Firefox as my browsers of choice, but I'd even consider using IE again if someone found a plugin that did this. Thanks, Max

    Read the article

  • displaying a WPF Window from a System.Configuration.Install.Installer class

    - by cbeuker
    Greetings all, I have a question. I have created a WPF application. So, I naturally created an installer (Visual Studio Install project) for it. In the Commit section of the installer I want to launch a WPF window which is my configuration wizard. So I created a Installer class, overrode the Commit method and put the following in method: Application theApp = new Application; theApp.Run (new MyWPFWizardWindow()); I keep getting the error: The calling thread must be STA, because many UI components require this. No problems, this makes as it is a GUI application. But I can't, for the life of me, get the installer to fire up my window. I have tried putting [STAThread] on the method. I have tried firing up a thread and setting the ApartmentState to STA. I am guessing it's something really simple that I am over looking. Anyone have any thoughts? Thanks in advance.. cmb..

    Read the article

  • boost::asio::io_service throws exception

    - by Ace
    Okay, I seriously cannot figure this out. I have a DLL project in MSVC that is attempting to use Asio (from Boost 1.45.0), but whenever I create my io_service, an exception is thrown. Here is what I am doing for testing purposes: void run() { boost::this_thread::sleep(boost::posix_time::seconds(5)); try { boost::asio::io_service io_service; } catch (std::exception & e) { MessageBox(NULL, e.what(), "Exception", MB_OK); } } BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) { if (fdwReason == DLL_PROCESS_ATTACH) { boost::thread thread(run); } return TRUE; } This is what the message box shows: winsock: WSAStartup cannot function at this time because the underlying system it uses to provide network services is currently unavailable Here is what MSDN says about it (error code 10091, WSASYSNOTREADY): Network subsystem is unavailable. This error is returned by WSAStartup if the Windows Sockets implementation cannot function at because the underlying system it uses to provide network services is currently unavailable. Users should check: That the appropriate Windows Sockets DLL file is in the current path. That they are not trying to use more than one Windows Sockets implementation simultaneously. If there is more than one Winsock DLL on your system, be sure the first one in the path is appropriate for the network subsystem currently loaded. The Windows Sockets implementation documentation to be sure all necessary components are currently installed and configured correctly. Yet none of this seems to apply to me (or so I think). Here is my command line: /O2 /GL /D "_WIN32_WINNT=0x0501" /D "_WINDLL" /FD /EHsc /MD /Gy /Fo"Release\" /Fd"Release\vc90.pdb" /W3 /WX /nologo /c /TP /errorReport:prompt If anyone knows what might be wrong, please help me out! Thanks.

    Read the article

< Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >