Search Results

Search found 9254 results on 371 pages for 'approach'.

Page 241/371 | < Previous Page | 237 238 239 240 241 242 243 244 245 246 247 248  | Next Page >

  • Rails - inheritance hierarchy of classes where a subtype can play two roles

    - by Miquel
    I need to model Owners and Rentees in an application, so you have stuff that is always owned by someone and can be rented for someone else. I first approached this problem with Single Table Inheritance because both types of person will share all attributes, so you would have a model called Person associated to a table people with Owner and Rentee inheriting from Person. The problem is that Single type inheritance discerns subtypes using a field type and therefore a record in the table can represent either an Owner or a Rentee but not both at the same time, while in the real context you can have an Owner which is renting something from another Owner and therefore that person is at the same time an Owner and a Rentee. How would you approach this problem? Would you use separated tables for owners and rentees? Is there any other type of table inheritance in Rails?

    Read the article

  • CoreData Model Objects for API

    - by theiOSguy
    I am using CoreData in my application. I want to abstract out all the CoreData related stuff as an API so that the consume can use the API instead of directly using CoreData and its generated model objects. CoreData generates the managed objects model as following @interface Person : NSManagedObject @end I want to define my API for example MyAPI and it has a function called as createPerson:(Person*)p; So the consumer of this createPerson API needs to create a Person data object (like POJO in java world) and invoke this API. But I cannot create Person object using Person *p = [Person alloc] init] because the designated initializer for this Person model created by CoreData does not allow this type of creation. So should I define corresponding user facing data object may be PersonDO and this API should take that instead to carry the data into the API implementation? Is my approach right? Any expert advise if design the API this way is a good design pattern?

    Read the article

  • Sed-replacing a pattern

    - by grails_enthu
    I have below code: <td nowrap="nowrap" width="74"> <p align="center">server1</p> </td> <td nowrap="nowrap" width="74"> <p align="center">server2</p> </td> and so on.I want to get output as: <td nowrap="nowrap" width="74">server1</td> <td nowrap="nowrap" width="74">server2</td> What should be my approach?Say for example the file is server.html I have done something like this: sed "s/<p align="center">*</p>/*/" -i server.html But its not working.

    Read the article

  • C++ DWORD* to BYTE*

    - by NomeSkavinski
    My issue, i am trying to convert and array of dynamic memory of type DWORD to a BYTE. Fair enough i can for loop through this and convert the DWORD into a BYTE per entry. But is their a faster way to do this? to take a pointer to DWORD data and convert the whole piece of data into a pointer to BYTE data? such as using a memcpy operation? I feel this is not possible, im not requesting an answer just an experienced opinion on my approach, as i have tried testing both approaches but seem to fail getting to a solution on my second solution. Thanks for any input, again no answers just a point in the right direction. Nor is this a homework question, i felt that had to be mentioned.

    Read the article

  • Trigger Backgroundworker Completed event.

    - by fireBand
    Hello, I am trying to display the progress bar(marque) in a separate form (progressForm) while i do some calculation in background. I know the typical way of doing it is to include the calculation in background worker and show progressForm in main thread. This approach how ever will lead to lot of synch issues in my application hence I am showing the progressForm using progressForm.ShowDialog() inside the background worker process. But I need to trigger the Completed event with in the application to close the form. Is this possible? Thanks in advance.

    Read the article

  • Breaking up large DataGridView for printing

    - by Hal
    Hey, I've got a single-row, 40 column-long DataGridView that i need to print. Since i can neither print it directly (because A4 sheets won't cut it ;)) nor adjust its width to the width of the page itself (because the headers look terrible), i wanted to break the DataGridView to 4 separate pieces and display 10 columns per row (imagine: column 1 to 10 in the first line, column 11 to 21 four or five lines below, etc...). Is there an easy way to do this? I was leaning towards a more manual approach (using fors), but i'd love to know if there's a more elegant way. Cheers

    Read the article

  • .Net using Chr() to parse text

    - by Marcx
    I'm building a simple client-server chat system. The clients send data to the server and the server resends the data to all the other clients. I'm using the TcpListener and Network stream classes to send the data between the client and the server. The fields I need to send are, for example: name, text, timestamp, etc. I separate them using the ASCII character 29. I'm also using ASCII character 30 to mark the end of the streamed data. The data is encoded with UTF8.. Is this a good approach? Will I run into problems? Are there better methods? UPDATE: Probably my question was misunderstood, so I explain it better.. Suppose to have a list of data to send from client to server, and suppose to send all the data in only one stream, how do you send these data? Using a markup Using a character as a delimiter Using a fixed length for every fields

    Read the article

  • How to model a relationship that NHibernate (or Hibernate) doesn’t easily support

    - by MylesRip
    I have a situation in which the ideal relationship, I believe, would involve Value Object Inheritance. This is unfortunately not supported in NHibernate so any solution I come up with will be less than perfect. Let’s say that: “Item” entities have a “Location” that can be in one of multiple different formats. These formats are completely different with no overlapping fields. We will deal with each Location in the format that is provided in the data with no attempt to convert from one format to another. Each Item has exactly one Location. “SpecialItem” is a subtype of Item, however, that is unique in that it has exactly two Locations. “Group” entities aggregate Items. “LocationGroup” is as subtype of Group. LocationGroup also has a single Location that can be in any of the formats as described above. Although I’m interested in Items by Group, I’m also interested in being able to find all items with the same Location, regardless of which group they are in. I apologize for the number of stipulations listed above, but I’m afraid that simplifying it any further wouldn’t really reflect the difficulties of the situation. Here is how the above could be diagrammed: Mapping Dilemma Diagram: (http://www.freeimagehosting.net/uploads/592ad48b1a.jpg) (I tried placing the diagram inline, but Stack Overflow won't allow that until I have accumulated more points. I understand the reasoning behind it, but it is a bit inconvenient for now.) Hmmm... Apparently I can't have multiple links either. :-( Analyzing the above, I make the following observations: I treat Locations polymorphically, referring to the supertype rather than the subtype. Logically, Locations should be “Value Objects” rather than entities since it is meaningless to differentiate between two Location objects that have all the same values. Thus equality between Locations should be based on field comparisons, not identifiers. Also, value objects should be immutable and shared references should not be allowed. Using NHibernate (or Hibernate) one would typically map value objects using the “component” keyword which would cause the fields of the class to be mapped directly into the database table that represents the containing class. Put another way, there would not be a separate “Locations” table in the database (and Locations would therefore have no identifiers). NHibernate (or Hibernate) do not currently support inheritance for value objects. My choices as I see them are: Ignore the fact that Locations should be value objects and map them as entities. This would take care of the inheritance mapping issues since NHibernate supports entity inheritance. The downside is that I then have to deal with aliasing issues. (Meaning that if multiple objects share a reference to the same Location, then changing values for one object’s Location would cause the location to change for other objects that share the reference the same Location record.) I want to avoid this if possible. Another downside is that entities are typically compared by their IDs. This would mean that two Location objects would be considered not equal even if the values of all their fields are the same. This would be invalid and unacceptable from the business perspective. Flatten Locations into a single class so that there are no longer inheritance relationships for Locations. This would allow Locations to be treated as value objects which could easily be handled by using “component” mapping in NHibernate. The downside in this case would be that the domain model becomes weaker, more fragile and less maintainable. Do some “creative” mapping in the hbm files in order to force Location fields to be mapped into the containing entities’ tables without using the “component” keyword. This approach is described by Colin Jack here. My situation is more complicated than the one he describes due to the fact that SpecialItem has a second Location and the fact that a different entity, LocatedGroup, also has Locations. I could probably get it to work, but the mappings would be non-intuitive and therefore hard to understand and maintain by other developers in the future. Also, I suspect that these tricky mappings would likely not be possible using Fluent NHibernate so I would use the advantages of using that tool, at least in that situation. Surely others out there have run into similar situations. I’m hoping someone who has “been there, done that” can share some wisdom. :-) So here’s the question… Which approach should be preferred in this situation? Why?

    Read the article

  • What is the correct way to customize Icon and Text position of items in a QListView?

    - by petermcg
    I'm using C++ and Qt's (4.6) model/view framework and wondering what is the correct way to change the display of items in a QListView or a class derived from QListView from: to: I'm not concerned about the sort order or Flow, I'm interested in the best way to correctly position the text to the right of the icon. If this can only be done by writing a custom QStyledItemDelegate that's totally fine, I want to rule out whether this is the correct approach or whether it's best to look at setLayout or similar, example code would help. The example application I'm looking at is the 'interview' example from qtdemo which amongst other things displays icons and text in a QListView.

    Read the article

  • How to insert an item into a key/value pair object?

    - by Clay
    Ok...here's a softball question... I just need to be able to insert a key/value pair into an object at a specific position. I'm currently working with a Hashtable which, of course, doesn't allow for this functionality. What would be the best approach? UPDATE: Also, I do need the ability to lookup by the key. For example...oversimplified and pseudocoded but should convey the point // existing Hashtable myHashtable.Add("somekey1", "somevalue1"); myHashtable.Add("somekey2", "somevalue2"); myHashtable.Add("somekey3", "somevalue3"); // Some other object that will allow me to insert a new key/value pair. // Assume that this object has been populated with the above key/value pairs. oSomeObject.Insert("newfirstkey","newfirstvalue"); Thanks in advance.

    Read the article

  • Arrange 0's & 1's in a array

    - by Ganesh M
    This is one of an interview question which I had recently. I would like to know others perception of approach for this problem. Question: You are given a structure which holds an employee details with two elements as int Deptartment and string Name. struct Employee { string Name; int Dept; } You are given details of N Employees among which there are N/2 employees Dept are 0's and N/2 employees dept are 1's arranged in some random order. You need to sort the employee details based on their Dept value and it should be stable i.e., the order of 1s and 0s in the original record should be maintained. For example, given the following sample data: Name Dept X1 0 X2 1 X3 0 X4 1 X5 0 after sorting the result should be: Name Dept X2 1 X4 1 X1 0 X3 0 X5 0 The algorithm should be stable and the complexity should be o(N), with constant space for additional variables (which means sorting should be done in-place).

    Read the article

  • Joining two select queries and ordering results

    - by user1
    Basically I'm just unsure as to why this query is failing to execute: (SELECT replies.reply_post, replies.reply_content, replies.reply_date AS d, members.username FROM (replies) AS a INNER JOIN members ON replies.reply_by = members.id) UNION (SELECT posts.post_id, posts.post_title, posts.post_date AS d, members.username FROM (posts) as b WHERE posts.post_set = 0 INNER JOIN members ON posts.post_by = members.id) ORDER BY d DESC LIMIT 5 I'm getting this error: #1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a INNER JOIN members ON replies.re' at line 2 All I'm trying to do is select the 5 most recent rows (dates) from these two tables. I've tried Join, union etc and I've seen numerous queries where people have put another query after the FROM statement and that just makes no logical sense to me as to how that works? Am I safe to say that you can join the same table from two different but joined queries? Or am I taking completely the wrong approach, because frankly I can't seem see how this query is failing despite reading the error message. (The two queries on there own work fine)

    Read the article

  • StringListProperty limited to 500 char strings (Google App Engine / Python)

    - by MarcoB
    It seems that StringListProperty can only contain strings up to 500 chars each, just like StringProperty... Is there a way to store longer strings than that? I don't need them to be indexed or anything. What I would need would be something like a "TextListProperty", where each string in the list can be any length and not limited to 500 chars. Can I create a property like that? Or can you experts suggest a different approach? Perhaps I should use a plain list and pickle/unpickle it in a Blob field, or something like that? I'm a bit new to Python and GAE and I would greatly appreciate some pointers instead of spending days on trial and error...thanks!

    Read the article

  • How can I return to a string address and then assign it to a new string?

    - by Y_Y
    I have 1 function that I want to return the address of an assigned string to the main function and assign an new string pointer with the same address so that the new string will have the contents of the old string. For example: unknown_datatype function() { char *old = "THE STRING"; return old; } int main() { char *snew = ""; snew = function(); return 0; } *unknown_datatype means I don't know that to put there... *How can I approach this without changing anything in the main() method

    Read the article

  • Cross vertion line matching.

    - by BCS
    I'm considering how to do automatic bug tracking and as part of that I'm wondering what is available to match source code line numbers (or more accurate numbers mapped from instruction pointers via something like addr2line) in one version of a program to the same line in another. (Assume everything is in some kind of source control and is available to my code) The simplest approach would be to use a diff tool/lib on the files and do some math on the line number spans, however this has some limitations: It doesn't handle cross file motion. It might not play well with lines that get changed It doesn't look at the information available in the intermediate versions. It provides no way to manually patch up lines when the diff tool gets things wrong. It's kinda clunky Before I start diving into developing something better: What already exists to do this? What features do similar system have that I've not thought of?

    Read the article

  • [GWT] StackLayoutPanel and MVP

    - by Stine
    Hello! Think there might be something about this MVP approach I have completely misunderstood. Currently I am struggling to apply the MVP pattern to the part of my application consisting of a StackLayoutPanel (accordion). To me it seems natural to have a presenter and a view per stack... but how do I allow the different presenters to react when the user switch the state of the stack panel? If someone could sketch an application of the MVP pattern in the case of an accordion application I would be really, really grateful! This is really getting on my nerves! ;D Thanks a lot from Stine :)

    Read the article

  • Best practices to test protected methods with PHPUnit

    - by GrGr
    Hello, I found the discussion on Do you test private method informative. I have decided, that in some classes, I want to have protected methods, but test them. Some of these methods are static and short. Because most of the public methods make use of them, I will probably be able to safely remove the tests later. But for starting with a TDD approach and avoid debugging, I really want to test them. I thought of the following: Method Object as adviced in an answer seems to be overkill for this. Start with public methods and when code coverage is given by higher level tests, turn them protected and remove the tests. Inherit a class with a testable interface making protected methods public Which is best practice? Is there anything else? It seems, that JUnit automatically changes protected methods to be public, but I did not have a deeper look at it. PHP does not allow this via reflection.

    Read the article

  • Creating Pages with unique PageMaps

    - by Michael Krauklis
    I have a wicket Application that has long lived Pages. I would like each instance of this Page to be created with a unique PageMap for reasons I won't get into here, but when I try to specify a PageMap on the constructor of my Page I end up getting OOM and StackOverflow errors. Here is the code: public <CTOR>() { super(Session.get().newPageMap("" + System.currentTimeMillis())); ... I'm using a custom BookmarkablePageLink (custom in that it does not pass on the current PageMap name to the new Page) to effectively abandon the old Page/PageMap and create a new one with a new PageMap. The errors seem to be coming from page serialization after only two or three pages have been created. Can anyone find issue with this approach?

    Read the article

  • Perl Email package

    - by aidan
    I'm looking for a simple (OO?) approach to email creation and sending. Something like $e = Email->new(to => "test <[email protected]>", from => "from <[email protected]>"); $e->plain_text($plain_version); $e->html($html_version); $e->attach_file($some_file_object); I've found Email::MIME::CreateHTML, which looks great in almost every way, except that it does not seem to support file attachments. Also, I'm considering writing these emails to a database and having a cronjob send them at a later date. This means that I would need a $e->as_text() sub to return the entire email, including attachments, as raw text which I could stuff into the db. And so I would then need a way of sending the raw emails - what would be a good way of achieving this? Many thanks

    Read the article

  • partially connected application using asp.net 3.5 (not mobile apps)

    - by Hari
    We had a requirement to build a ASP.NET 3.5 web application using web forms, WCF, ADO.NET and SQL Server. The users would connect via Internet. Recently we understood that it is possible that users would often remain disconnected and would have Internet access intermittently. I need to understand if we can create occasionally connected web application using asp.net 3.5 - what all technologies/features we need to use? Is MS Sync Framework the answer to the problem - is it a viable option to use with web application? Is windows application the right approach instead of web applications - where the business logic would be run at the client itself, using local SQL Express editions with data then been synced up with Enterprise SQL server at server end when connection is established using replication and/or MS Sync framework. In that case is there a need to use WCF? Does Silverlight applications help in this context -building paritally connected web apps? Really appreciate if you can give pointers to how to go about this task of creating .net partially connected apps (not mobile apps)?

    Read the article

  • Disabling identity (auto-incrementing) on integer primary key using code first

    - by gw0
    I am using code first approach in a ASP.NET MVC 3 application and all integer primary keys in models (public int Id { get; set; }) are by default configured as an identity with auto-incrementing. How to disable this and enable a way to manually enter the integer for the primary key? The actual situation is that the Id integers have a special meaning and I would therefore like to have them choosable at creation and later editable. It would be ideal if in case the integer is not given at creation time it is auto-incremented, else the specified value is used. But editable primary fields is my primary need. Is there any way to do this elegantly in ASP.NET MVC 3?

    Read the article

  • IIS serving corrupted MSI

    - by CF_Maintainer
    Hello, I am trying to put an .msi for download in a virtual directory setup with IIS. The download works fine but when I try and install the .msi, it says it is missing a _cabinet file. Me and a coworker had this issue will the installer downloaded fine & ran correctly on another coworker's machine. Am I missing anything? Is it a better approach to send the .msi as a byte[] via a webservice and assemble it on the client side?

    Read the article

  • Storing database records into array

    - by zerey
    I would want to create an array that will hold records retrieved from a database using a query of SELECT statement. The records to be retrieved have multiple fields such as lastname, firstname, mi and 20 more fields. What would be the best approach on coding this function? alright i have followed what prisoner have given below.. the next question is how do i search through this kind of array using queries? for example i want to search for a username..

    Read the article

  • replace asp.net Response.Output with my own content

    - by WebDude
    I am trying to intercept a asp.net web request and based on a lookup replace the page thats going to be rendered to the client. example: is a request for "/about-us" comes to my web server, i will first see if i have a version of this in the database, otherwise i will revert to flat files. The version i will retrieve from the database will be a .aspx page that has to be rendered and containt web controls and inline serverside script. What is the best way to go about this? I have tried overriding the CreateHtmlTextWriter method but this seems too late in the process as the TextWriter passed to this method is already instantiated. I have also tried to Implement my own PageHandlerFactory but this seems to create an instance of Page of which i cannot seem to override its internal setting of the Response.Output stream. Amd i barking up the wrong tree here? what is the best approach to take here?

    Read the article

  • Beginning Programmer Interested in Android - Should I Start with Java?

    - by Hudey
    I'm a beginner in programming. My experience so far is only in Actionscript 2 and 3. So I have a basic understanding of declaring variables, loops, arrays, if/then, do/while... I'm wanting to move to developing for Android phones so I'm wondering what suggestions people have for where to go next. Should I jump right to Android? Start with a 'beginning Java' approach? Or should I go some other route to beef up my knowledge of OOP concepts before launching into Android? I have my Dev environment set up and completed the Hello Android tutorial and I'm just wondering if I am going to be in over my head quickly?

    Read the article

< Previous Page | 237 238 239 240 241 242 243 244 245 246 247 248  | Next Page >