Search Results

Search found 14602 results on 585 pages for 'objected oriented design'.

Page 531/585 | < Previous Page | 527 528 529 530 531 532 533 534 535 536 537 538  | Next Page >

• DataSets to POCOs - an inquiry regarding DAL architecture

  - by alexsome

  Hello all, I have to develop a fairly large ASP.NET MVC project very quickly and I would like to get some opinions on my DAL design to make sure nothing will come back to bite me since the BL is likely to get pretty complex. A bit of background: I am working with an Oracle backend so the built-in LINQ to SQL is out; I also need to use production-level libraries so the Oracle EF provider project is out; finally, I am unable to use any GPL or LGPL code (Apache, MS-PL, BSD are okay) so NHibernate/Castle Project are out. I would prefer - if at all possible - to avoid dishing out money but I am more concerned about implementing the right solution. To summarize, there are my requirements: Oracle backend Rapid development (L)GPL-free Free I'm reasonably happy with DataSets but I would benefit from using POCOs as an intermediary between DataSets and views. Who knows, maybe at some point another DAL solution will show up and I will get the time to switch it out (yeah, right). So, while I could use LINQ to convert my DataSets to IQueryable, I would like to have a generic solution so I don't have to write a custom query for each class. I'm tinkering with reflection right now, but in the meantime I have two questions: Are there any problems I overlooked with this solution? Are there any other approaches you would recommend to convert DataSets to POCOs? Thanks in advance.

  Read the article

• Android GPS cloud of confusion!

  - by Anthony Forloney

  I am trying to design my first Android application with the use of GPS. As of right now, I have a drawable button that when clicked, alerts a Toast message of the longitude and latitude. I have tried to use the telnet localhost 5554 and then geo fix #number #number to feed in values but no results display just 0 0. I have also tried DDMS way of sending GPS coordinates and I get the same thing. My question is what exactly is the code equivalent to the geo fix and the DDMS way of sending coordinates. I have used Location, LocationManger and LocationListener but I am not sure which is the right choice. Could anyone explain to me what the code-equivalent just so I can get a better understanding of how to fix my application not working. Code is given, just in case if the error exists with the code @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button button = (Button) findViewById(R.id.track); button.setOnClickListener(this); LocationManager location =(LocationManager)getSystemService(Context.LOCATION_SERVICE); Location loc = location.getLastKnownLocation(location.GPS_PROVIDER); updateWithNewLocation(loc); } private final LocationListener locationListener = new LocationListener() { public void onLocationChanged(Location location) { updateWithNewLocation(location); } private void updateWithNewLocation(Location l) { longitude = l.getLongitude(); latitude = l.getLatitude(); provider = l.getProvider(); } public void onClick(View v) { Toast.makeText(this, "Your location is " + longitude + " and " + latitude + " provided by: " + provider, Toast.LENGTH_SHORT).show(); } }

  Read the article

• window.setInterval from inside an object

  - by Keith Rousseau

  I'm currently having an issue where I have a javascript object that is trying to use setInterval to call a private function inside of itself. However, it can't find the object when I try to call it. I have a feeling that it's because window.setInterval is trying to call into the object from outside but doesn't have a reference to the object. FWIW - I can't get it to work with the function being public either. The basic requirement is that I may need to have multiple instances of this object to track multiple uploads that are occurring at once. If you have a better design than the current one or can get the current one working then I'm all ears. The following code is meant to continuously ping a web service to get the status of my file upload: var FileUploader = function(uploadKey) { var intervalId; var UpdateProgress = function() { $.get('someWebService', {}, function(json) { alert('success'); }); }; return { BeginTrackProgress: function() { intervalId = window.setInterval('UpdateProgress()', 1500); }, EndTrackProgress: function() { clearInterval(intervalId); } }; }; This is how it is being called: var fileUploader = new FileUploader('myFileKey'); fileUploader.BeginTrackProgress();

  Read the article

• G++ Multi-platform memory leak detection tool

  - by indyK1ng

  Does anyone know where I can find a memory memory leak detection tool for C++ which can be either run in a command line or as an Eclipse plug-in in Windows and Linux. I would like it to be easy to use. Preferably one that doesn't overwrite new(), delete(), malloc() or free(). Something like GDB if its gonna be in the command line, but I don't remember that being used for detecting memory leaks. If there is a unit testing framework which does this automatically, that would be great. This question is similar to other questions (such as http://stackoverflow.com/questions/283726/memory-leak-detection-under-windows-for-gnu-c-c ) however I feel it is different because those ask for windows specific solutions or have solutions which I would rather avoid. I feel I am looking for something a bit more specific here. Suggestions don't have to fulfill all requirements, but as many as possible would be nice. Thanks. EDIT: Since this has come up, by "overwrite" I mean anything which requires me to #include a library or which otherwise changes how C++ compiles my code, if it does this at run time so that running the code in a different environment won't affect anything that would be great. Also, unfortunately, I don't have a Mac, so any suggestions for that are unhelpful, but thank you for trying. My desktop runs Windows (I have Linux installed but my dual monitors don't work with it) and I'd rather not run Linux in a VM, although that is certainly an option. My laptop runs Linux, so I can use that tool on there, although I would definitely prefer sticking to my desktop as the screen space is excellent for keeping all of the design documentation and requirements in view without having to move too much around on the desktop. NOTE: While I may try answers, I won't mark one as accepted until I have tried the suggestion and it is satisfactory. EDIT2: I'm not worried about the cross-platform compatibility of my code, it's a command line application using just the C++ libraries.

  Read the article

• Use continue or Checked Exceptions when checking and processing objects

  - by Johan Pelgrim

  I'm processing, let's say a list of "Document" objects. Before I record the processing of the document successful I first want to check a couple of things. Let's say, the file referring to the document should be present and something in the document should be present. Just two simple checks for the example but think about 8 more checks before I have successfully processed my document. What would have your preference? for (Document document : List<Document> documents) { if (!fileIsPresent(document)) { doSomethingWithThisResult("File is not present"); continue; } if (!isSomethingInTheDocumentPresent(document)) { doSomethingWithThisResult("Something is not in the document"); continue; } doSomethingWithTheSucces(); } Or for (Document document : List<Document> documents) { try { fileIsPresent(document); isSomethingInTheDocumentPresent(document); doSomethingWithTheSucces(); } catch (ProcessingException e) { doSomethingWithTheExceptionalCase(e.getMessage()); } } public boolean fileIsPresent(Document document) throws ProcessingException { ... throw new ProcessingException("File is not present"); } public boolean isSomethingInTheDocumentPresent(Document document) throws ProcessingException { ... throw new ProcessingException("Something is not in the document"); } What is more readable. What is best? Is there even a better approach of doing this (maybe using a design pattern of some sort)? As far as readability goes my preference currently is the Exception variant... What is yours?

  Read the article

• Any info about book "Unix Internals: The New Frontiers" by Uresh Vahalia 2nd edition (Jan 2010)

  - by claws

  This summer I'm getting into UNIX (mostly *BSD) development. I've graduate level knowledge about operating systems. I can also understand the code & read from here and there but the thing is I want to make most of my time. Reading books are best for this. From my search I found that these two books The Design and Implementation of the 4.4 BSD Operating System "Unix Internals: The New Frontiers" by Uresh Vahalia are like established books on UNIX OS internals. But the thing is these books are pretty much outdated. yay!! Lucky me. "Unix Internals: The New Frontiers" by Uresh Vahalia 2 edition (Jan 2010) is released. I've been search for information on this book. Sadly, Amazon says "Out of Print--Limited Availability" & I couldn't find any info regarding this book. This is the information I'm looking for: Table of Contents Whats new in this edition? Where the hell can I buy soft-copy of this book? I really cannot afford buying a hardcopy. How can I contact the author? I've lot of hopes & expectations on this book. I've been waiting for its release for a long time. I've sent random mails to & & requesting to have a proper website for this book. I even contacted publisher for any further information but no replies from any one. If you have any other books that you think will help me. I again repeat, I want to get max possible out of these 2.5 months summer.

  Read the article

• Why do bind1st and bind2nd require constant function objects?

  - by rlbond

  So, I was writing a C++ program which would allow me to take control of the entire world. I was all done writing the final translation unit, but I got an error: error C3848: expression having type 'const `anonymous-namespace'::ElementAccumulator<T,BinaryFunction>' would lose some const-volatile qualifiers in order to call 'void `anonymous-namespace'::ElementAccumulator<T,BinaryFunction>::operator ()(const point::Point &,const int &)' with [ T=SideCounter, BinaryFunction=std::plus<int> ] c:\program files (x86)\microsoft visual studio 9.0\vc\include\functional(324) : while compiling class template member function 'void std::binder2nd<_Fn2>::operator ()(point::Point &) const' with [ _Fn2=`anonymous-namespace'::ElementAccumulator<SideCounter,std::plus<int>> ] c:\users\****\documents\visual studio 2008\projects\TAKE_OVER_THE_WORLD\grid_divider.cpp(361) : see reference to class template instantiation 'std::binder2nd<_Fn2>' being compiled with [ _Fn2=`anonymous-namespace'::ElementAccumulator<SideCounter,std::plus<int>> ] I looked in the specifications of binder2nd and there it was: it took a const AdaptibleBinaryFunction. So, not a big deal, I thought. I just used boost::bind instead, right? Wrong! Now my take-over-the-world program takes too long to compile (bind is used inside a template which is instantiated quite a lot)! At this rate, my nemesis is going to take over the world first! I can't let that happen -- he uses Java! So can someone tell me why this design decision was made? It seems like an odd decision. I guess I'll have to make some of the elements of my class mutable for now...

  Read the article

• MySQL Normalization stored procedure performance

  - by srkiNZ84

  Hi, I've written a stored procedure in MySQL to take values currently in a table and to "Normalize" them. This means that for each value passed to the stored procedure, it checks whether the value is already in the table. If it is, then it stores the id of that row in a variable. If the value is not in the table, it stores the newly inserted value's id. The stored procedure then takes the id's and inserts them into a table which is equivalent to the original de-normailized table, but this table is fully normalized and consists of mainly foreign keys. My problem with this design is that the stored procedure takes approximately 10ms or so to return, which is too long when you're trying to work through some 10million records. My suspicion is that the performance is to do with the way in which I'm doing the inserts. i.e. INSERT INTO TableA (first_value) VALUES (argument_from_sp) ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id); SET @TableAId = LAST_INSERT_ID(); The "ON DUPLICATE KEY UPDATE" is a bit of a hack, due to the fact that on a duplicate key I don't want to update anything but rather just return the id value of the row. If you miss this step though, the LAST_INSERT_ID() function returns the wrong value when you're trying to run the "SET ..." statement. Does anyone know of a better way to do this in MySQL? Thank you

  Read the article

• Winsock WSAAsyncSelect sending without an infinite buffer

  - by Xexr

  Hi, This is more of a design question than a specific code question, I'm sure I am missing the obvious, I just need another set of eyes. I am writing a multi-client server based on WSAAsyncSelect, each connection is made into an object of a connection class I have written which contains associated settings and buffers etc. My question concerns FD_WRITE, I understand how it operates: One FD_WRITE is sent immediately after a connection is established. Thereafter, you should send until WSAEWOULDBLOCK is received at which point you store what is left to send in a buffer, and wait to be told that it is ok to send again. This is where I have a problem, how large do I make this holding buffer within each connections object? The amount of time until a new FD_WRITE is received is unknown, I could be attempting to send a lot of stuff during this period, all the time adding to my outgoing buffer. If I make the buffer dynamic, memory usage could spiral out of control if for whatever reason, I am unable to send() and reduce the buffer. So my question is how do you generally handle this situation? Note I am not talking about the network buffer itself which winsock uses, but one of my own creation used to "queue" up sends. Hope I explained that well enough, thanks all!

  Read the article

• Good PHP / MYSQL hashing solution for large number of text values

  - by Dave

  Short descriptio: Need hashing algorithm solution in php for large number of text values. Long description. PRODUCT_OWNER_TABLE serial_number (auto_inc), product_name, owner_id OWNER_TABLE owner_id (auto_inc), owener_name I need to maintain a database of 200000 unique products and their owners (AND all subsequent changes to ownership). Each product has one owner, but an owner may have MANY different products. Owner names are "Adam Smith", "John Reeves", etc, just text values (quite likely to be unicode as well). I want to optimize the database design, so what i was thinking was, every week when i run this script, it fetchs the owner of a proudct, then checks against a table i suppose similar to PRODUCT_OWNER_TABLE, fetching the owner_id. It then looks up owner_id in OWNER_TABLE. If it matches, then its the same, so it moves on. The problem is when its different... To optimize the database, i think i should be checking against the other "owner_name" entries in OWNER_TABLE to see if that value exists there. If it does, then i should use that owner_id. If it doesnt, then i should add another entry. Note that there is nothing special about the "name". as long as i maintain the correct linkagaes AND make the OWNER_TABLE "read-only, append-new" type table - I should be able create a historical archive of ownership. I need to do this check for 200000 entries, with i dont know how many unique owner names (~50000?). I think i need a hashing solution - the OWNER_TABLE wont be sorted, so search algos wont be optimal. programming language is PHP. database is MYSQL.

  Read the article

• When do instance variables get initialized and values assigned?

  - by AKh

  When doees the instance variable get initialized? Is it after the constructor block is done or before it? Consider this example: public abstract class Parent { public Parent(){ System.out.println("Parent Constructor"); init(); } public void init(){ System.out.println("parent Init()"); } } public class Child extends Parent { private Integer attribute1; private Integer attribute2 = null; public Child(){ super(); System.out.println("Child Constructor"); } public void init(){ System.out.println("Child init()"); super.init(); attribute1 = new Integer(100); attribute2 = new Integer(200); } public void print(){ System.out.println("attribute 1 : " +attribute1); System.out.println("attribute 2 : " +attribute2); } } public class Tester { public static void main(String[] args) { Parent c = new Child(); ((Child)c).print(); } } OUTPUT: Parent Constructor Child init() parent Init() Child Constructor attribute 1 : 100 attribute 2 : null When the memory for the atribute 1 & 2 are allocated in the heap ? Curious to know why is attribute 2 is NULL ? Are there any design flaws?

  Read the article

• Overlapping template partial specialization when wanting an "override" case: how to avoid the error?

  - by user173342

  I'm dealing with a pretty simple template struct that has an enum value set by whether its 2 template parameters are the same type or not. template<typename T, typename U> struct is_same { enum { value = 0 }; }; template<typename T> struct is_same<T, T> { enum { value = 1 }; }; This is part of a library (Eigen), so I can't alter this design without breaking it. When value == 0, a static assert aborts compilation. So I have a special numerical templated class SpecialCase that can do ops with different specializations of itself. So I set up an override like this: template<typename T> struct SpecialCase { ... }; template<typename LT, typename RT> struct is_same<SpecialCase<LT>, SpecialCase<RT>> { enum { value = 1 }; }; However, this throws the error: more than one partial specialization matches the template argument list Now, I understand why. It's the case where LT == RT, which steps on the toes of is_same<T, T>. What I don't know is how to keep my SpecialCase override and get rid of the error. Is there a trick to get around this? edit: To clarify, I need all cases where LT != RT to also be considered the same (have value 1). Not just LT == RT.

  Read the article

• MouseMotion Sensor Method Call

  - by user321894

  I have a soon-to-be due assignment due in computer science. I have encountered a problem, for which no matter how long I study the API's of the class and superclasses, I can not figure out. Suppose I wish to design a sort of "Breakout game" where the mouse motion controls the motion of a block that is used to bounce a ball, which then destroys multi colored bricks. How do you specifically make the block "listen" to the mouse? The below code is what I have attempted to achieve the desired results. /** Breakout Program*/ public class Breakout extends GraphicsProgram implements MouseMotionListener { ... /** The Paddle Itself */ private GRect paddle = new GRect(0, HEIGHT-PADDLEBOTTOM_OFFSET, PADDLEWIDTH, PADDLEHEIGHT); ... /** Run the Breakout program. */ public void run() { paddle.setFillColor(Color.BLACK); paddle.setFilled(true); add(paddle); paddle.addMouseListener(this); ... } /** Move the horizontal middle of the paddle to the x-coordinate of the mouse position - * -but keep the paddle completely on the board. */ public void mouseMoved(MouseEvent e) { GPoint p= new GPoint(e.getPoint()); double x = p.getX(); paddle.setLocation(x, HEIGHT-PADDLEBOTTOM_OFFSET); } } Any clarification on why/what I am doing incorrectly would be helpful, thanks.

  Read the article

• Website Live Chat Script - Interface With Windows Live Messenger?

  - by Sootah

  Hello again fellow StackOverflow users! What I am looking for currently is your opinions on the what the best live chat script would be for my website. I'd be using this on both my local computer repair (which I've not really set up yet) company's site, as well as my other technical support site that is geared more towards showing people how to fix whatever problem they have themselves. It'll be a little bit before I launch it on either site, as I need to find a good design for my local computer repair company's site, as well as redesign TweaksForGeeks.com's layout so that it's more magazine like. (If you have any suggestions on good Wordpress templates for these, that'd also be swell. :) ) Features I'd like for the live chat script to have: (if possible) Real-time posting of messages (or as close to real time as possible) Integration into my Windows Live Messenger account - By this I mean it'd be handy if instead of me having to man a separate open browser window and constantly check it for new messages, it'd be much more convenient if it would instead just allow me to receive and respond to messages via my Windows Live account the same way I'd chat with any other person on my contact list. Sound notification of new messages when the chat isn't the focused window - In the event that using Windows Messenger isn't possible then I'd need it to notify me upon receipt of a new message. Recording of chat transcripts - This is a MUST HAVE Easy customization - I'll likely want to modify how it looks and whatnot, in addition to the fact that I'm going to set it up so that the chat transcripts can be posted to my site easily in order to be useful to my other visitors later on. With all that in mind, what is available out there? I've not really researched this at all yet; aside from doing a cursory search just before I decided to ask my StackOverflow brothers. As always, thank you! -Sootah

  Read the article

• Content Management Systems for Adaptive Content [closed]

  - by andrewap

  Content management systems (CMS) allow us to easily maintain blogs, news sites, general websites, and so on. Many of them are designed to manage pages of content, and provide tools to organize and customize how that content is displayed on the web. However, as explained by Mark Boulton in his Adaptive Content Management article, and by Karen McGrane in her talk on Adapting Ourselves to Adaptive Content, we are increasingly delivering content not just to the web, but also to other platforms and channels. We need tools to manage pieces of content with meaningful metadata attached. Create once, publish everywhere. The main idea is to store content cleanly, without intertwining it with presentation markup specific to the web. Because pieces of content is compartmentalized semantically, it can easily adapt to fit in different platforms and channels. Hence, it's called adaptive content. Let's look at a quick example to compare: Say I manage news articles and events. To create a news article, I would tell the CMS the type of content I'm creating, and be asked to fill in a form with individual fields tailored to news articles (e.g. headline, subtitle, full text, short snippet, and images). — i.e. pieces of content With a traditional web publishing tool, I would probably have had to create a new page under News, and then type in and format the news article in a blank WYSIWYG text editor. — i.e. pages of content As you can see, the first design allows me to individually specify content in its smallest semantic unit. When I want to display or consume it, the system can easily provide the pieces I need. So here's my question: Is there a CMS that is designed specifically with adaptive content in mind, and that is decoupled with the presentation layer? Note: This is not a discussion about the best CMS, or which CMS I should use. I am asking whether a very specific type of tool — CMS designed for adaptive content — exists for developers to use.

  Read the article

• templete class c++

  - by inna karpasas

  hi! i try to design a templete for my universty project. i wrote the follwing cod: #ifndef _LinkedList_H_ #define _LinkedList_H_ #include "Link.h" #include <ostream> template <class L>//error one class LinkedList { private: Link<L> *pm_head; Link<L> * pm_tail; int m_numOfElements; Link<L>* FindLink(L * dataToFind); public: LinkedList(); ~LinkedList(); int GetNumOfElements(){return m_numOfElements;} bool Add( L * data); L *FindData(L * data); template <class L> friend ostream & operator<<(ostream& os,const LinkedList<L> listToprint);//error two L* GetDataOnTop(); bool RemoveFromHead(); L* Remove(L * toRemove); this templete uses the link class templete #ifndef _Link_H_ #define _Link_H_ template <class T>//error 3 class Link { private: T* m_data; Link* m_next; Link* m_prev; public: Link(T* data); ~Link(void); bool Link::operator ==(const Link& other)const; /*getters*/ Link* GetNext()const {return m_next;} Link* GetPrev()const {return m_prev;} T* GetData()const {return m_data;} //setters void SetNext(Link* next) {m_next = next;} void SetPrev(Link* prev) {m_prev = prev;} void SetData(T* data) {m_data = data;} }; error one: shadows template parm class L' error two:declaration ofclass L' error three: shadows template parm `class T' i dont understand what is the problem. i can relly usr your help thank you :)

  Read the article

• How should I progressively enhance this content with JavaScript?

  - by Sean Dunwoody

  The background to this problem is that I'm doing a computing project which involves Some drop down boxes for input, and a text input where the user can input a date. I've used YUI to enhance the form, so the calendar input uses the YUI calendar widget and the drop down list is converted into a horizontal list of inputs where the user only has to click once to select any input as opposed to two clicks with the drop down box (hope that makes sense, not sure how to explain it clearly) The problem is, that in the design section of my project I stated that I would follow the progressive enhancement principles. I am struggling however to ensure that users without JavaScript are able to view the drop down box / text input on said page. This is not because I do not necessarily know how, but the two methods I've tried seem unsatisfactory. Method 1 - I tried using YUI to hide the text box and drop down list, this seemed like the ideal solution however there was quite a noticeable lag when loading the page (especially for the first time), the text box and drop down list where visibile for at least a second. I included the script for this just before the end of the body tag, is there any way that I can run it onload with YUI? Would that help? Method 2 - Use the noscript tag . . . however I am loathed to do this as while it would be a simple solution, I have read various bad things about the noscript tag. Is there a way of making mehtod one work? Or is there a better way of doing this that I am yet to encounter?

  Read the article

• using dummy row with NOT NULL to solve DEFAULT NULL

  - by Tony38

  I know having DEFAULT NULLS is not a good practice but I have many optional lookup values which are FK in the system so to solve this issue here is what i am doing: I use NOT NULL for every FK / lookup colunms. I have the first row in every lookup table which is PK id = 1 as a dummy row with just "none" in all the columns. This way I can use NOT NULL in my schema and if needed reference to the none row values PK =1 for FKs which do not have any lookup value. Is this a good design or any other work arounds? EDIT: I have: Neighborhood table Postal table. Every neighborhood has a city, so the FK can be NOT NULL. But not every postal code belongs to a neighborhood. Some do, some don't depending on the country. So if i use NOT NULL for the FK between postal and neighborhood then I will be screwed as there has to be some value entered. So what i am doing in essence is: have a row in every table to be a dummy row just to link the FKs. This way row one in neighborhood table will be: n_id = 1 name =none etc... In postal table I can have: postal_code = 3456A3 FK (city) = Moscow FK (neighborhood_id)=1 as a NOT NULL. If I don't have a dummy row in the neighborhood lookup table then I have to declare FK (neighborhood_id) as a Default null column and store blanks in the table. This is an example but there is a huge number of values which will have blanks then in many tables.

  Read the article

• Use XML Layout to contain a simple drawing

  - by user329999

  I would like to create a simple drawing (lines, circles, squares, etc...) but I'm having difficulty figuring out the best way to do this. The drawing would need to be scaled to fit the display since the size is indirectly specified by the user (like in a CAD application). Also, I don't want to take up the entire display, leaving room for some controls (buttons, etc). I would pass the data to describe the drawing. Here's how I imagine it would work. I create an XML layout that contains something that holds the drawing (ImageView, BitmapDrawable, ShapeDrawable, ...??? not sure exactly what). Then in my Activity I would load the main XML and obtain the resource for the control that holds the drawing. I would then draw to a bitmap. Once the bitmap was completed I would load it into the control that is to hold the drawing. Somewhere along this path it would be scaled to fill the entire area allocated for the drawing in the XML layout. I don't know if my approach is the way to do this or what classes to use. I read the http://developer.android.com/guide/topics/graphics/2d-graphics.html documentation, but it's not helping me with an example. The examples I do find leave me with hints, but nothing concrete enough to do what I want, especially when it comes to scaling, using XML and/or having other controls. Also, there seems to be no good documentation on the design of the 2D drawing system in a more conceptual manner, so it makes what I read difficult to put into any useful context. Any hints on what classes would be useful and/or a good example any other reading materials? Thanks

  Read the article

• Where is the Open Source alternative to WPF?

  - by Evan Plaice

  If we've learned anything from HTML/CSS it's that, declarative languages (like XML) work best to describe User Interfaces because: It's easy to build code preprocessors that can template the code effectively. The code is in a well defined well structured (ideally) format so it's easy to parse. The technology to effectively parse or crawl an XML based source file already exists. The UIs scripted code becomes much simpler and easier to understand. It simple enough that designers are able to design the interface themselves. Programmers suck at creating UIs so it should be made easy enough for designers. I recently took a look at the meat of a WPF application (ie. the XAML) and it looks surprisingly familiar to the declarative language style used in HTML. It's blindingly apparent to me that the current state of desktop UI development is largely fractionalized, otherwise there wouldn't be so much duplicated effort in the domain of user interfaces (IE. GTK, XUL, Qt, Winforms, WPF, etc). There are 45 GUI platforms for Python alone It's painfully obvious to me that there should be a general purpose, open source, standardized, platform independent, markup language for designing desktop GUIs. Much like what the W3C made HTML/CSS into. WPF, or more specifically XAML seems like a pretty likely step in the right direction. Why hasn't anyone in the Open Source community (AFAIK) even scratched the surface of this issue. Now that the 'browser wars' are over should we look forward to a future of 'desktop gui wars?' Note: This topic is relatively subjective in the attempt to be 'future-thinking.' I think that desktop GUI development in its current state sucks ((really)hard) and, even though WPF is still in it's infancy, it presents a likely solution to the problem. Has no one in the OS community looked into developing something similar because they don't see the value, or because it's not worth the effort?

  Read the article

• What constitutes a development environment, and how do you document it?

  - by Joel Coehoorn

  What items go into a software shop's development environment, how do you document it, and what processes do you follow to make changes? I thinking about this from the standpoint where I want to make it easier to bring new hires up to speed quickly by having all this on a checklist we follow when setting them up, and then while I'm at it making it easier for the new hires or existing team members to bring new powerful toolkits and ideas into the environment without disrupting things. I want to keep this platform agnostic, so even though I'm currently at a microsoft shop where Visual Studio would be assumed I'll go ahead and list compiler/IDE as one of the items: Here are some ideas for part 1: [edit]: I'm keeping this updated based on the better suggestions. Source Control access Issue/Bug/Project tracker System Documention, or references to find the system documentation in source control or in a wiki, including: build document/environment covered by this question design documents / technical notes Coding Style guidelines Deploy for review/testing/QA/staging/production procedures Licensing details for your tools and your product Team Calendar, including the project schedule(s), deadlines, vacation time, and support/on-call schedule (if required) compiler/IDE compiler/IDE extensions (things like source control plugins or visual studio add-ins) 3rd party SDKs/toolkits Database connection and tools Testing Frameworks Internal libraries communication tools (chat, wiki, etc) Static analysis tools (FxCop, FlawFinder, etc) Virtual machines (holding dev environment or for testing) Specialized editors (modeling, xml, etc) Other tools What else goes in this list, and how do you document it and vet changes?

  Read the article

• Two questions on ensuring EndInvoke() gets called on a list of IAsyncResult objects

  - by RobV

  So this question is regarding the .Net IAsyncResult design pattern and the necessity of calling EndInvoke as covered in this question Background I have some code where I'm firing off potentially many asynchronous calls to a particular function and then waiting for all these calls to finish before using EndInvoke() to get back all the results. Question 1 I don't know whether any of the calls has encountered an exception until I call EndInvoke() and in the event that an exception occurs in one of the calls the entire method should fail and the exception gets wrapped into an API specific exception and thrown upwards. So my first question is what's the best way then to ensure that the remainder of the async calls get properly terminated? Is a finally block which calls EndInvoke() on the remainder of the unterminated calls (and ignores any further exceptions) the best way to do this? Question 2 Secondly when I first fire off all my asyc calls I then call WaitHandle.WaitAll() on the array of WaitHandle instances that I've got from my IAsyncResult instances. The method which is firing all these async calls has a timeout to adhere to so I provide this to the WaitAll() method. Then I test whether all the calls have completed, if not then the timeout must have been reached so the method should also fail and throw another API specific exception. So my second question is what should I do in this case? I need to call EndInvoke() to terminate all these async calls before I throw the error but at the same time I don't want the code to get stuck since EndInvoke() is blocking. In theory at least if the WaitAll() call times out then all the async calls should themselves have timed out and thrown exceptions (thus completing the call) since they are also governed by a timeout but this timeout is potentially different from the main timeout

  Read the article

• Unity IoC and MVC modelbinding

  - by danielovich

  Is it ok to have a static field in my controller for my modelbinder to call ? Eg. public class AuctionItemsController : Controller { private IRepository<IAuctionItem> GenericAuctionItemRepository; private IAuctionItemRepository AuctionItemRepository; public AuctionItemsController(IRepository<IAuctionItem> genericAuctionItemRepository, IAuctionItemRepository auctionItemRepository) { GenericAuctionItemRepository = genericAuctionItemRepository; AuctionItemRepository = auctionItemRepository; StaticGenericAuctionItemRepository = genericAuctionItemRepository; } internal static IRepository<IAuctionItem> StaticGenericAuctionItemRepository; here is the modelbinder public class AuctionItemModelBinder : DefaultModelBinder { public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) { if (AuctionItemsController.StaticGenericAuctionItemRepository != null) { AuctionLogger.LogException(new Exception("controller is null")); } NameValueCollection form = controllerContext.HttpContext.Request.Form; var item = AuctionItemsController.StaticGenericAuctionItemRepository.GetSingle(Convert.ToInt32(controllerContext.RouteData.Values["id"])); item.Description = form["title"]; item.Price = int.Parse(form["price"]); item.Title = form["title"]; item.CreatedDate = DateTime.Now; item.AuctionId = 1; //TODO: Stop hardcoding this item.UserId = 1; return item; }} i am using Unity as IoC and I find it weird to register my modelbinder in the IoC container. Any other good design considerations I shold do ?

  Read the article

• Does QThread::sleep() require the event loop to be running?

  - by suszterpatt

  I have a simple client-server program written in Qt, where processes communicate using MPI. The basic design I'm trying to implement is the following: The first process (the "server") launches a GUI (derived from QMainWindow), which listens for messages from the clients (using repeat fire QTimers and asynchronous MPI receive calls), updates the GUI depending on what messages it receives, and sends a reply to every message. Every other process (the "clients") runs in an infinite loop, and all they are intended to do is send a message to the server process, receive the reply, go to sleep for a while, then wake up and repeat. Every process instantiates a single object derived from QThread, and calls its start() method. The run() method of these classes all look like this: from foo.cpp: void Foo::run() { while (true) { // Send message to the first process // Wait for a reply // Do uninteresting stuff with the reply sleep(3); // also tried QThread::sleep(3) } } In the client's code, there is no call to exec() anywhere, so no event loop should start. The problem is that the clients never wake up from sleeping (if I surround the sleep() call with two writes to a log file, only the first one is executed, control never reaches the second). Is this because I didn't start the event loop? And if so, what is the simplest way to achieve the desired functionality?

  Read the article

• Setting up relations/mappings for a SQLAlchemy many-to-many database

  - by Brent Ramerth

  I'm new to SQLAlchemy and relational databases, and I'm trying to set up a model for an annotated lexicon. I want to support an arbitrary number of key-value annotations for the words which can be added or removed at runtime. Since there will be a lot of repetition in the names of the keys, I don't want to use this solution directly, although the code is similar. My design has word objects and property objects. The words and properties are stored in separate tables with a property_values table that links the two. Here's the code: from sqlalchemy import Column, Integer, String, Table, create_engine from sqlalchemy import MetaData, ForeignKey from sqlalchemy.orm import relation, mapper, sessionmaker from sqlalchemy.ext.declarative import declarative_base engine = create_engine('sqlite:///test.db', echo=True) meta = MetaData(bind=engine) property_values = Table('property_values', meta, Column('word_id', Integer, ForeignKey('words.id')), Column('property_id', Integer, ForeignKey('properties.id')), Column('value', String(20)) ) words = Table('words', meta, Column('id', Integer, primary_key=True), Column('name', String(20)), Column('freq', Integer) ) properties = Table('properties', meta, Column('id', Integer, primary_key=True), Column('name', String(20), nullable=False, unique=True) ) meta.create_all() class Word(object): def __init__(self, name, freq=1): self.name = name self.freq = freq class Property(object): def __init__(self, name): self.name = name mapper(Property, properties) Now I'd like to be able to do the following: Session = sessionmaker(bind=engine) s = Session() word = Word('foo', 42) word['bar'] = 'yes' # or word.bar = 'yes' ? s.add(word) s.commit() Ideally this should add 1|foo|42 to the words table, add 1|bar to the properties table, and add 1|1|yes to the property_values table. However, I don't have the right mappings and relations in place to make this happen. I get the sense from reading the documentation at http://www.sqlalchemy.org/docs/05/mappers.html#association-pattern that I want to use an association proxy or something of that sort here, but the syntax is unclear to me. I experimented with this: mapper(Word, words, properties={ 'properties': relation(Property, secondary=property_values) }) but this mapper only fills in the foreign key values, and I need to fill in the other value as well. Any assistance would be greatly appreciated.

  Read the article

< Previous Page | 527 528 529 530 531 532 533 534 535 536 537 538  | Next Page >