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  • Uniform grid Rows and Columns

    - by Carlo
    I'm trying to make a grid based on a UniformGrid to show the coordinates of each cell, and I want to show the values on the X and Y axes like so: _A_ _B_ _C_ _D_ 1 |___|___|___|___| 2 |___|___|___|___| 3 |___|___|___|___| 4 |___|___|___|___| Anyway, in order to do that I need to know the number of columns and rows in the Uniform grid, and I tried overriding the 3 most basic methods where the arrangement / drawing happens, but the columns and rows in there are 0, even though I have some controls in my grid. What method can I override so my Cartesian grid knows how many columns and rows it has? C#: public class CartesianGrid : UniformGrid { protected override Size MeasureOverride(Size constraint) { Size size = base.MeasureOverride(constraint); int computedColumns = this.Columns; // always 0 int computedRows = this.Rows; // always 0 return size; } protected override Size ArrangeOverride(Size arrangeSize) { Size size = base.ArrangeOverride(arrangeSize); int computedColumns = this.Columns; // always 0 int computedRows = this.Rows; // always 0 return size; } protected override void OnRender(DrawingContext dc) { int computedColumns = this.Columns; // always 0 int computedRows = this.Rows; // always 0 base.OnRender(dc); } } XAML: <local:CartesianGrid> <Label Content="Hello" /> <Label Content="Hello" /> <Label Content="Hello" /> <Label Content="Hello" /> <Label Content="Hello" /> <Label Content="Hello" /> </local:CartesianGrid> Any help is greatly appreciated. Thanks!

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  • c++ templates and inheritance

    - by Armen Ablak
    Hey, I'm experiencing some problems with breaking my code to reusable parts using templates and inheritance. I'd like to achieve that my tree class and avltree class use the same node class and that avltree class inherits some methods from the tree class and adds some specific ones. So I came up with the code below. Compiler throws an error in tree.h as marked below and I don't really know how to overcome this. Any help appreciated! :) node.h: #ifndef NODE_H #define NODE_H #include "tree.h" template <class T> class node { T data; ... node() ... friend class tree<T>; }; #endif tree.h #ifndef DREVO_H #define DREVO_H #include "node.h" template <class T> class tree { public: //signatures tree(); ... void insert(const T&); private: node<T> *root; //missing type specifier - int assumed. Note: C++ does not support default-int }; //implementations #endif avl.h #ifndef AVL_H #define AVL_H #include "tree.h" #include "node.h" template <class T> class avl: public tree<T> { public: //specific int findMin() const; ... protected: void rotateLeft(node<T> *)const; private: node<T> *root; }; #endif avl.cpp (I tried separating headers from implementation, it worked before I started to combine avl code with tree code) #include "drevo" #include "avl.h" #include "vozlisce.h" template class avl<int>; //I know that only avl with int can be used like this, but currently this is doesn't matter :) //implementations ...

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  • Accessing a struct collection property from within another collection

    - by paddyb
    I have a struct that I need to store in a collection. The struct has a property that returns a Dictionary. public struct Item { private IDictionary<string, string> values; public IDictionary<string, string> Values { get { return this.values ?? (this.values = new Dictionary<string, string>()); } } } public class ItemCollection : Collection<Item> {} When testing I've found that if I add the item to the collection and then try to access the dictionary the structs values property is never updated. var collection = new ItemCollection { new Item() }; // pre-loaded with an item collection[0].Values.Add("myKey", "myValue"); Trace.WriteLine(collection[0].Values["myKey"]); // KeyNotFoundException here However if I load up the item first and then add it to a collection the values field is maintained. var collection = new ItemCollection(); var item = new Item(); item.Values.Add("myKey", "myValue"); collection.Add(item); Trace.WriteLine(collection[0].Values["myKey"]); // ok I've already decided that a struct is the wrong option for this type, and when using a class the issue doesn't occur, but I'm curious what's different between the two methods. Can anybody explain what's happening?

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  • How do you pass a generic delegate argument to a method in .NET 2.0

    - by Seth Spearman
    Hello, I have a class with a delegate declaration as follows... Public Class MyClass Public Delegate Function Getter(Of TResult)() As TResult 'the following code works. Public Shared Sub MyMethod(ByVal g As Getter(Of Boolean)) 'do stuff End Sub End Class However, I do not want to explicitly type the Getter delegate in the Method call. Why can I not declare the parameter as follows... ... (ByVal g As Getter(Of TResult)) Is there a way to do it? My end goal was to be able to set a delegate for property setters and getters in the called class. But my reading indicates you can't do that. So I put setter and getter methods in that class and then I want the calling class to set the delegate argument and then invoke. Is there a best practice for doing this. I realize in the above example that I can set set the delegate variable from the calling class...but I am trying to create a singleton with tight encapsulation. For the record, I can't use any of the new delegate types declared in .net35. Answers in C# are welcome. Any thoughts? Seth

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  • JavaScript: List global variables in IE

    - by Quandary
    I'm trying to get the instance name of my class. The way I do this is I loop through all global objects and compare it with the this pointer. It works in Chrome and FF, but in IE, it doesn't. The problem seems to be the global variables don't seem to be in window. How can I loop through the global variables in IE ? PS: I know it only works as long as there is only one instance, and I don't want to pass the instance's name as a parameter. function myClass() { this.myName = function () { // search through the global object for a name that resolves to this object for (var name in this.global) { if (this.global[name] == this) return name } } } function myClass_chrome() { this.myName = function () { // search through the global object for a name that resolves to this object for (var name in window) { if (window[name] == this) return name ; } } ; } // store the global object, which can be referred to as this at the top level, in a // property on our prototype, so we can refer to it in our object's methods myClass.prototype.global = this //myClass_IE.prototype.global = this // create a global variable referring to an object // var myVar = new myClass() var myVar = new myClass_chrome() //var myVar = new myClass_IE() alert(myVar.myName() );// returns "myVar"

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  • Converting string to a simple type

    - by zespri
    .Net framework contains a great class named Convert that allows conversion between simple types, DateTime type and String type. Also the class support conversion of the types implementing IConvertible interface. The class has been implemented in the very first version of .Net framework. There were a few things in the first .Net framework that were not done quite right. For example .Parse methods on simple types would throw an exception if the string couldn't be parsed and there would be no way to check if exception is going to be thrown in advance. A future version of .Net Framework removed this deficiency by introducing the TryParse method that resolved this problem. The Convert class dates back to time of the old Parse method, so the ChangeType method on this class in implemented old style - if conversion can't be performed an exception is thrown. Take a look at the following code: public static T ConvertString<T>(string s, T @default) { try { return (T)Convert.ChangeType(s, typeof(T), CultureInfo.InvariantCulture); } catch (Exception) { return @default; } } This code basically does what I want. However I would pretty much like to avoid the ugly try/catch here. I'm sure, that similar to TryParse, there is a modern method of rewriting this code without the catch-all. Could you suggest one?

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  • C++: Maybe you know this fitfall?

    - by Martijn Courteaux
    Hi, I'm developing a game. I have a header GameSystem (just methods like the game loop, no class) with two variables: int mouseX and int mouseY. These are updated in my game loop. Now I want to access them from Game.cpp file (a class built by a header-file and the source-file). So, I #include "GameSystem.h" in Game.h. After doing this I get a lot of compile errors. When I remove the include he says of course: Game.cpp:33: error: ‘mouseX’ was not declared in this scope Game.cpp:34: error: ‘mouseY’ was not declared in this scope Where I want to access mouseX and mouseY. All my .h files have Header Guards, generated by Eclipse. I'm using SDL and if I remove the lines that wants to access the variables, everything compiles and run perfectly (*). I hope you can help me... This is the error-log when I #include "GameSystem.h" (All the code he is refering to works, like explained by the (*)): In file included from ../trunk/source/domein/Game.h:14, from ../trunk/source/domein/Game.cpp:8: ../trunk/source/domein/GameSystem.h:30: error: expected constructor, destructor, or type conversion before ‘*’ token ../trunk/source/domein/GameSystem.h:46: error: variable or field ‘InitGame’ declared void ../trunk/source/domein/GameSystem.h:46: error: ‘Game’ was not declared in this scope ../trunk/source/domein/GameSystem.h:46: error: ‘g’ was not declared in this scope ../trunk/source/domein/GameSystem.h:46: error: expected primary-expression before ‘char’ ../trunk/source/domein/GameSystem.h:46: error: expected primary-expression before ‘bool’ ../trunk/source/domein/FPS.h:46: warning: ‘void FPS_SleepMilliseconds(int)’ defined but not used This is the code which try to access the two variables: SDL_Rect pointer; pointer.x = mouseX; pointer.y = mouseY; pointer.w = 3; pointer.h = 3; SDL_FillRect(buffer, &pointer, 0xFF0000);

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  • C++, generic programming and virtual functions. How do I get what I want?

    - by carleeto
    This is what I would like to do using templates: struct op1 { virtual void Method1() = 0; } ... struct opN { virtual void MethodN() = 0; } struct test : op1, op2, op3, op4 { virtual void Method1(){/*do work1*/}; virtual void Method2(){/*do work2*/}; virtual void Method3(){/*do work3*/}; virtual void Method4(){/*do work4*/}; } I would like to have a class that simply derives from a template class that provides these method declarations while at the same time making them virtual. This is what I've managed to come up with: #include <iostream> template< size_t N > struct ops : ops< N - 1 > { protected: virtual void DoStuff(){ std::cout<<N<<std::endl; }; public: template< size_t i > void Method() { if( i < N ) ops<i>::DoStuff(); } //leaving out compile time asserts for brevity } struct test : ops<6> { }; int main( int argc, char ** argv ) { test obj; obj.Method<3>(); //prints 3 return 0; } However, as you've probably guessed, I am unable to override any of the 6 methods I have inherited. I'm obviously missing something here. What is my error? No, this isn't homework. This is curiosity.

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  • Playing craps, asking and printing

    - by Angelo Mejia
    How do I ask the amount of games of craps someone wants to play and print the number of wins as a result of n number of games? Also How do I make a table in the main method using the previous methods I have? A table like this but shows the results: Percent Wins Games Experiment Number 1 2 3 4 5 6 7 8 9 10 100 1000 10000 100000 1000000 public class CrapsAnalysis { public static int rollDie( int n) { return (int)(Math.random()*n) + 1 ; } public static int rollDice( ) { int die1 ; int die2 ; die1 = rollDie(6) ; die2 = rollDie(6) ; return die1 + die2 ; } public static boolean playOneGame( ) { int newDice ; //repeated dice rolls int roll ; //first roll of the dice int playerPoint = 0 ; //player point if no win or loss on first roll newDice = rollDice() ; roll = rollDice() ; if (roll == 7 || roll == 11) return true; else if (roll == 2 || roll == 3 || roll == 12) return false; else { playerPoint = roll; newDice = rollDice(); do { newDice = rollDice(); } while (newDice != playerPoint || newDice != 7) ; if (newDice == 7) return false; else return true; } } public static int playGames ( int n ) { int numWon = 0; for (int i = 1; i <= n; i++) if(playOneGame()) numWon++; return numWon; } public static void main(String[] args) { //Don't know how to ask and print out the results of the number of wins depending on the n number of games played } }

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  • GridView ObjectDataSource LINQ Paging and Sorting using multiple table query.

    - by user367426
    I am trying to create a pageing and sorting object data source that before execution returns all results, then sorts on these results before filtering and then using the take and skip methods with the aim of retrieving just a subset of results from the database (saving on database traffic). this is based on the following article: http://www.singingeels.com/Blogs/Nullable/2008/03/26/Dynamic_LINQ_OrderBy_using_String_Names.aspx Now I have managed to get this working even creating lambda expressions to reflect the sort expression returned from the grid even finding out the data type to sort for DateTime and Decimal. public static string GetReturnType<TInput>(string value) { var param = Expression.Parameter(typeof(TInput), "o"); Expression a = Expression.Property(param, "DisplayPriceType"); Expression b = Expression.Property(a, "Name"); Expression converted = Expression.Convert(Expression.Property(param, value), typeof(object)); Expression<Func<TInput, object>> mySortExpression = Expression.Lambda<Func<TInput, object>>(converted, param); UnaryExpression member = (UnaryExpression)mySortExpression.Body; return member.Operand.Type.FullName; } Now the problem I have is that many of the Queries return joined tables and I would like to sort on fields from the other tables. So when executing a query you can create a function that will assign the properties from other tables to properties created in the partial class. public static Account InitAccount(Account account) { account.CurrencyName = account.Currency.Name; account.PriceTypeName = account.DisplayPriceType.Name; return account; } So my question is, is there a way to assign the value from the joined table to the property of the current table partial class? i have tried using. from a in dc.Accounts where a.CompanyID == companyID && a.Archived == null select new { PriceTypeName = a.DisplayPriceType.Name}) but this seems to mess up my SortExpression. Any help on this would be much appreciated, I do understand that this is complex stuff.

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  • iPhone Custom CA certificate for an application which uses NSURLConnection?

    - by jr
    I have an application which is communicating with many different sites and each site has its own SSL certificate signed by our own internal CA. Doing this prevents us the need from purchasing SSL certificates for each site (hundreds or thousands) and is more secure then using a wildcard certificate with a shared key on each of those sites. So, basically using a CA certificate is the only way. Right now, I have a mobileprovision file which will install the CA certificate as a profile on the phone. When our iPhone application launches if it gets an SSL Certificate error it redirects to a this mobile provision file via Safari and the user will be prompted to install the CA. The problem is that I am concerned that the Apple AppStore might deny my app for doing this (Just some feedback from other developers at this point), and I wanted to research other ways to accomplish this. Basically what I need to accomplish is allow an SSL connection which will verify against a custom CA certificate which will be embedded in my application. This will make the CA certificate active for only the calls I make. I am using the standard NSURLConnection methods in order to communicate with the service. Is this possible? Can someone show me how to load the CA (what form PEM?) and add it to the list of trusted CA certificates for my application? If that is not possible what other options do I have? Just trusting all certificates isn't really any option, we want to prevent man in the middle attacks and only trust our CA issued certificates. Thanks!

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  • Creating object/array to method in request based on __gettypes in PHP

    - by LochNess
    I'm having trouble with the array or object that should be passed based on the response from __gettypes. The __gettypes response: [0] => struct CDataWrapper { schema;any; } [1] => struct NewMember { MemberDetail MemberDetails;ArrayOfHobby Hobbies; } [2] => struct MemberDetail { string Name; string Age; string Sex; } [3] => struct ArrayOfHobby { Hobby Hobby; } [4] => struct Hobby { string Name; string HoursUsedOnHobbyWeekly;boolean Favourite; } ... etc. The methods are: [0] => ReceiveMemberResponse ReceiveMember(ReceiveMember $parameters) [1] => ReturnMemberResponse ReturnMember(ReturnMember $parameters) So far I have this PHP: $client = new SoapClient('http://domain.com?wsdl'); class MemberDetail { public $Name = ''; public $Age = ''; public $Sex = ''; } $mc = new MemberDetail(); $mc->Name= 'Bob'; $mc->Age= '14'; $mc->Sex= 'Male'; $myParam = array('ReceiveMember'=>$mc); $wcf = $client->ReceiveMember($myParam); $wcfResult = $wcf->ReturnMember; print_r($wcfResult) when i call the page it returns: Error 324 (net::ERR_EMPTY_RESPONSE): Unknown error. I'm not really sure how to create the array or object to pass on as $myParam since im no expert with PHP either.

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  • Python finding substring between certain characters using regex and replace()

    - by jCuga
    Suppose I have a string with lots of random stuff in it like the following: strJunk ="asdf2adsf29Value=five&lakl23ljk43asdldl" And I'm interested in obtaining the substring sitting between 'Value=' and '&', which in this example would be 'five'. I can use a regex like the following: match = re.search(r'Value=?([^&>]+)', strJunk) >>> print match.group(0) Value=five >>> print match.group(1) five How come match.group(0) is the whole thing 'Value=five' and group(1) is just 'five'? And is there a way for me to just get 'five' as the only result? (This question stems from me only having a tenuous grasp of regex) I am also going to have to make a substitution in this string such such as the following: val1 = match.group(1) strJunk.replace(val1, "six", 1) Which yields: 'asdf2adsf29Value=six&lakl23ljk43asdldl' Considering that I plan on performing the above two tasks (finding the string between 'Value=' and '&', as well as replacing that value) over and over, I was wondering if there are any other more efficient ways of looking for the substring and replacing it in the original string. I'm fine sticking with what I've got but I just want to make sure that I'm not taking up more time than I have to be if better methods are out there.

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  • Can I get a reference to an object created in a jQuery plugin?

    - by gargantaun
    Perhaps my brain is fried, but I'm writing a plugin that created an tweaks an element, but also creates an object that i'd like access to. So the plugin looks like this (function ($) { $.fn.myPlugin = function () { return this.each(function () { // do some stuff to the element... this.objectInstance = new usefulObject(); }); }; })(jQuery); function usefulObject(){ // useful object properties and methods.... this.doSomething = function(){ alert("Don't google Google. You'll break the internet."); } } so when I call the plugin, I also want to be able to get access to that usefulObject that I created. I thought something like this might work.... tweakedElement = $("#someDiv").myPlugin(); tweakedElement.objectInstance.doSomething(); ... but that's not working. How can I achieve this? Can I achieve this? Answers on a postcard, or down below, whichever suits you.

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  • How do I alias the scala setter method 'myvar_$eq(myval)' to something more pleasing when in java?

    - by feydr
    I've been converting some code from java to scala lately trying to teach myself the language. Suppose we have this scala class: class Person() { var name:String = "joebob" } Now I want to access it from java so I can't use dot-notation like I would if I was in scala. So I can get my var's contents by issuing: person = Person.new(); System.out.println(person.name()); and set it via: person = Person.new(); person.name_$eq("sallysue"); System.out.println(person.name()); This holds true cause our Person Class looks like this in javap: Compiled from "Person.scala" public class Person extends java.lang.Object implements scala.ScalaObject{ public Person(); public void name_$eq(java.lang.String); public java.lang.String name(); public int $tag() throws java.rmi.RemoteException; } Yes, I could write my own getters/setters but I hate filling classes up with that and it doesn't make a ton of sense considering I already have them -- I just want to alias the _$eq method better. (This actually gets worse when you are dealing with stuff like antlr because then you have to escape it and it ends up looking like person.name_\$eq("newname"); Note: I'd much rather have to put up with this rather than fill my classes with more setter methods. So what would you do in this situation?

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  • Dimension Reduction in Categorical Data with missing values

    - by user227290
    I have a regression model in which the dependent variable is continuous but ninety percent of the independent variables are categorical(both ordered and unordered) and around thirty percent of the records have missing values(to make matters worse they are missing randomly without any pattern, that is, more that forty five percent of the data hava at least one missing value). There is no a priori theory to choose the specification of the model so one of the key tasks is dimension reduction before running the regression. While I am aware of several methods for dimension reduction for continuous variables I am not aware of a similar statical literature for categorical data (except, perhaps, as a part of correspondence analysis which is basically a variation of principal component analysis on frequency table). Let me also add that the dataset is of moderate size 500000 observations with 200 variables. I have two questions. Is there a good statistical reference out there for dimension reduction for categorical data along with robust imputation (I think the first issue is imputation and then dimension reduction)? This is linked to implementation of above problem. I have used R extensively earlier and tend to use transcan and impute function heavily for continuous variables and use a variation of tree method to impute categorical values. I have a working knowledge of Python so if something is nice out there for this purpose then I will use it. Any implementation pointers in python or R will be of great help. Thank you.

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  • Conversion between different template instantiation of the same template

    - by Naveen
    I am trying to write an operator which converts between the differnt types of the same implementation. This is the sample code: template <class T = int> class A { public: A() : m_a(0){} template <class U> operator A<U>() { A<U> u; u.m_a = m_a; return u; } private: int m_a; }; int main(void) { A<int> a; A<double> b = a; return 0; } However, it gives the following error for line u.m_a = m_a;. Error 2 error C2248: 'A::m_a' : cannot access private member declared in class 'A' d:\VC++\Vs8Console\Vs8Console\Vs8Console.cpp 30 Vs8Console I understand the error is because A<U> is a totally different type from A<T>. Is there any simple way of solving this (may be using a friend?) other than providing setter and getter methods? I am using Visual studio 2008 if it matters.

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  • What's the best way to communicate the purpose of a string parameter in a public API?

    - by Dave
    According to the guidance published in New Recommendations for Using Strings in Microsoft .NET 2.0, the data in a string may exhibit one of the following types of behavior: A non-linguistic identifier, where bytes match exactly. A non-linguistic identifier, where case is irrelevant, especially a piece of data stored in most Microsoft Windows system services. Culturally-agnostic data, which still is linguistically relevant. Data that requires local linguistic customs. Given that, I'd like to know the best way to communicate which behavior is expected of a string parameter in a public API. I wasn't able to find an answer in the Framework Design Guidelines. Consider the following methods: f(string this_is_a_linguistic_string) g(string this_is_a_symbolic_identifier_so_use_ordinal_compares) Is variable naming and XML documentation the best I can do? Could I use attributes in some way to mark the requirements of the string? Now consider the following case: h(Dictionary<string, object> dictionary) Note that the dictionary instance is created by the caller. How do I communicate that the callee expects the IEqualityComparer<string> object held by the dictionary to perform, for example, a case-insensitive ordinal comparison?

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  • Cannot Find Symbol Method?

    - by Aaron
    In my driver program, This line gives me cannot find symbol error and I don't know why, the method is clearly defined in the SavingsAccount class, and I can refer to all other methods in my driver program but just not that one, I tried changing the type to double, and etc but still not working. Refer to ** Account acct2 = new SavingsAccount (name); acct2.calculateBalance(); SavingsAccount Class Inherited from Account Class: public class SavingsAccount extends Account { private final short minBalance = 0; private double overdraftFee; private double yearlyInterestRate = 0.02; private double interestAmount; public SavingsAccount (String name) { super(name); } public double withdraw (double amount) { if (accountBalance - amount >= minBalance) { accountBalance -= amount; System.out.print ("Withdraw Successful"); } else { accountBalance -= amount; overdraftFee = accountBalance * (0.10); accountBalance += overdraftFee; System.out.print ("Withdraw Succesful, however overdraft fee of 10% has been applied to your account"); } return accountBalance; } **public void calculateBalance () { interestAmount = (accountBalance * yearlyInterestRate); accountBalance += interestAmount; }** public String toString() { return super.toString() + " Interest Received: " + interestAmount; } } Account class, if needed import java.util.Random; import java.text.NumberFormat; public abstract class Account { protected double accountBalance; protected long accountNumber; protected String accountHolder; public Account (String name) { accountHolder = name; accountBalance = 0; Random accountNo = new Random(); accountNumber = accountNo.nextInt(100000); } public double deposit (double amount) { accountBalance += amount; return accountBalance; } public String toString() { NumberFormat accountBal = NumberFormat.getCurrencyInstance(); return "Account Balance: " + accountBal.format(accountBalance) + "\nAccount Number: " + accountNumber; } public String getAccountHolder() { return accountHolder; } public double getAccountBalance() { return accountBalance; } public abstract double withdraw (double amount); }

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  • Entity framework with Linq to Entities performance

    - by mare
    If I have a static method like this public static string GetTicClassificationTitle(string classI, string classII, string classIII) { using (TicDatabaseEntities ticdb = new TicDatabaseEntities()) { var result = from classes in ticdb.Classifications where classes.ClassI == classI where classes.ClassII == classII where classes.ClassIII == classIII select classes.Description; return result.FirstOrDefault(); } } and use this method in various places in foreach loops or just plain calling it numerous times, does it create and open new connection every time? If so, how can I tackle this? Should I cache the results somewhere, like in this case, I would cache the entire Classifications table in Memory Cache? And then do queries vs this cached object? Or should I make TicDatabaseEntities variable static and initialize it at class level? Should my class be static if it contains only static methods? Because right now it is not.. Also I've noticed that if I return result.First() instead of FirstOrDefault() and the query does not find a match, it will issue an exception (with FirstOrDefault() there is no exception, it returns null). Thank you for clarification.

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  • How should I handle expected errors? eg. "username already exists"

    - by Pheter
    I am struggling to understand how I should design the error handling parts of my code. I recently asked a similar question about how I should go about returning server error codes to the user, eg. 404 errors. I learnt that I should handle the error from within the current part of the application; seem's simple enough. However, what should I do when I can't handle the error from the current link in the chain? For example, I may have a class that is used to manage authentication. One of it's methods could be createUser($username, $password). Within that function, I need to determine if the username already exists. If this is true, how should I alert the calling code about this? Returning null instead of a user object is one way. But how do I then know what caused the error? How should I handle errors in such a way that calling code can easily find out what caused the error? Is there a design pattern commonly used for this kind of situation?

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  • Self organizing layouts

    - by user613326
    Quite a while ago i was more in websites building then i am now. In my time there where huge debates about what to use; tables or pure CSS alternatives. I went out of the webdesigning, but now an old question re-surfaces. What i would like to create is a web page design that depending on screensize, would self organize the page into columns, so that for example on a PDA it would show 1 column On an old computer monitor, it would show 2 colomns, and on a widescreen laptop it would show 3 columns. I forgot how this was called and how it was done in the past, it had to do with XML and storing data seperate from design (if i remember well), perhaps these days better methods exist to do that, does this, anyone ring this a bell ? Also i note a lot is possible with Jquery and and brouwser depending webkits. But i need to make sure that it would run on all (modern) brouwsers : Iexplorer, Firefox, chrome And Jquery is nice too, but i am kinda woried that some day one of these brouwser vendors decides that jscript like java isnt enabled by default (or is that very unlikely ?)11 Perhaps someone can point me to a method that is the prefered way to do this.

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  • How to insert several thousand columns into sqlite3?

    - by user291071
    Similar to my last question, but I ran into problem lets say I have a simple dictionary like below but its Big, when I try inserting a big dictionary using the methods below I get operational error for the c.execute(schema) for too many columns so what should be my alternate method to populate an sql databases columns? Using the alter table command and add each one individually? import sqlite3 con = sqlite3.connect('simple.db') c = con.cursor() dic = { 'x1':{'y1':1.0,'y2':0.0}, 'x2':{'y1':0.0,'y2':2.0,'joe bla':1.5}, 'x3':{'y2':2.0,'y3 45 etc':1.5} } # 1. Find the unique column names. columns = set() for _, cols in dic.items(): for key, _ in cols.items(): columns.add(key) # 2. Create the schema. col_defs = [ # Start with the column for our key name '"row_name" VARCHAR(2) NOT NULL PRIMARY KEY' ] for column in columns: col_defs.append('"%s" REAL NULL' % column) schema = "CREATE TABLE simple (%s);" % ",".join(col_defs) c.execute(schema) # 3. Loop through each row for row_name, cols in dic.items(): # Compile the data we have for this row. col_names = cols.keys() col_values = [str(val) for val in cols.values()] # Insert it. sql = 'INSERT INTO simple ("row_name", "%s") VALUES ("%s", "%s");' % ( '","'.join(col_names), row_name, '","'.join(col_values) )

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  • Any guidelines for handling the Headset and Bluetooth AVRC transport controls in Android 2.2

    - by StefanK
    I am trying to figure out what is the correct (new) approach for handling the Intent.ACTION_MEDIA_BUTTON in Froyo. In pre 2.2 days we had to register a BroadcastReceiver (either permanently or at run-time) and the Media Button events would arrive, as long as no other application intercepts them and aborts the broadcast. Froyo seems to still somewhat support that model (at least for the wired headset), but it also introduces the registerMediaButtonEventReceiver, and unregisterMediaButtonEventReceiver methods that seem to control the "transport focus" between applications. During my experiments, using registerMediaButtonEventReceiver does cause both the bluetooth and the wired headset button presses to be routed to the application's broadcast receiver (the app gets the "transport focus"), but it looks like any change in the audio routing (for example unplugging the headset) shits the focus back to the default media player. What is the logic behind the implementation in Android 2.2? What is correct way to handle transport controls? Do we have to detect the change in the audio routing and try to re-gain the focus? This is an issue that any 3rd party media player on the Android platform has to deal with, so I hope that somebody (probably a Google Engineer) can provide some guidelines that we can all follow. Having a standard approach may make headset button controls a bit more predictable for the end users. Stefan

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  • JSR-299 (CDI) configuration at runtime

    - by nsn
    I need to configure different @Alternatives, @Decorators and @Injectors for different runtime environments (think testing, staging and production servers). Right now I use maven to create three wars, and the only difference between those wars are in the beans.xml files. Is there a better way to do this? I do have @Alternative @Stereotypes for the different environments, but even then I need to alter beans.xml, and they don't work for @Decorators (or do they?) Is it somehow possible to instruct CDI to ignore the values in beans.xml and use a custom configuration source? Because then I could for example read a system property or other environment variable. The application exclusively runs in containers that use Weld, so a weld-specific solution would be ok. I already tried to google this but can't seem to find good search terms, and I asked the Weld-Users-Forums, but to no avail. Someone over there suggested to write my own custom extension, but I can't find any API to actually change the container configuration at runtime. I think it would be possible to have some sort of @ApplicationScoped configuration bean and inject that into all @Decorators which could then decide themselves whether they should be active or not and then in order to configure @Alternatives write @Produces methods for every interface with multiple implementations and inject the config bean there too. But this seems to me like a lot of unnecessary work to essentially duplicate functionality already present in CDI?

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