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  • Adding an keyUp-event to form objects

    - by reporter
    Hello folks, I've got the issue to add a browser event to some input fields. The challenge I have to face is, that one parameter of my target function is the 'event'-variable and the second one an object. For a better understanding here some codes:The HTML object: <div id="1_dateFieldAdvanced" class="xp set"> <div id="1_dateFieldAdvanced_label" class="label">Birthday</div> <div id="1_dateFieldAdvanced_value" class="value date"> <input class="day" name="dayOfBirth" value="66" maxlength="2" type="text"> <input class="month" name="monthOfBirth" value="67" maxlength="2" type="text"> <input class="year" name="yearOfBirth" value="" maxlength="4" type="text"> </div> </div> The source code of target method is like below: function advancedDateFields(currentFieldAsObject, nextField, currentValueLength, ev){} Unfortunatly the HTML and the Javascript code is generated automatically, so I'm unable to refactore the code. My question is, how can I pass the key word 'event' and the other parameters? My tries did always fail. :-(

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  • What is a good RPC model for building a AJAX web app using PHP & JS?

    - by user366152
    I'm new to writing AJAX applications. I plan on using jQuery on the client side while PHP on the server side. I want to use something like XML-RPC to simplify my effort in calling server-side code. Ideally, I wouldn't care whether the transport layer uses XML or JSON or a format more optimized for the wire. If I was writing a console app I'd use some tool to generate function stubs which I would then implement on the RPC server while the client would natively call into those stubs. This provides a clean separation. Is there something similar available in the AJAX world? While on this topic, how would I proceed with session management? I would want it to be as transparent as possible. For example, if I try to hit an RPC end-point which needs a valid session, it should reject the request if the client doesn't pass a valid session cookie. This would really ease my application development. I'd then have to simply handle the frontend using native JS functions. While on the backend, I can simply implement the RPC functions. BTW I dont wish to use Google Web Toolkit. My app wont be extremely heavy on AJAX.

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  • Get parameter values from method at run time

    - by Landin Martens
    I have the current method example: public void MethodName(string param1,int param2) { object[] obj = new object[] { (object) param1, (object) param2 }; //Code to that uses this array to invoke dynamic methods } Is there a dynamic way (I am guessing using reflection) that will get the current executing method parameter values and place them in a object array? I have read that you can get parameter information using MethodBase and MethodInfo but those only have information about the parameter and not the value it self which is what I need. So for example if I pass "test" and 1 as method parameters without coding for the specific parameters can I get a object array with two indexes { "test", 1 }? I would really like to not have to use a third party API, but if it has source code for that API then I will accept that as an answer as long as its not a huge API and there is no simple way to do it without this API. I am sure there must be a way, maybe using the stack, who knows. You guys are the experts and that is why I come here. Thank you in advance, I can't wait to see how this is done. EDIT It may not be clear so here some extra information. This code example is just that, an example to show what I want. It would be to bloated and big to show the actual code where it is needed but the question is how to get the array without manually creating one. I need to some how get the values and place them in a array without coding the specific parameters.

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  • Call instance method with objc_msgSend

    - by user772349
    I'm trying to use the objc_msgSend method to call some method dynamically. Say I want call some method in Class B from Class A and there are two methods in class B like: - (void) instanceTestWithStr1:(NSString *)str1 str2:(NSString *)str1; + (void) methodTestWithStr1:(NSString *)str1 str2:(NSString *)str1; And I can call the class method like this in Class A successfully: objc_msgSend(objc_getClass("ClassB"), sel_registerName("methodTestWithStr1:str2:"), @"111", @"222"); And I can call the instance method like this in Class A successfully as well: objc_msgSend([[objc_getClass("ClassB") alloc] init], sel_registerName("instanceTestWithStr1:str2:"), @"111", @"222"); But the thing is to get a instance of Class B I have to call "initWithXXXXX:XXXXXX:XXXXXX" instead of "init" so that to pass some necessary parameters to class B to do the init stuff. So I stored a instance of ClassB in class A as variable: self.classBInstance = [[ClassB alloc] initWithXXXXX:XXXXXX:XXXXXX]; And then I call the method like this (successfully): The problem is, I want to call a method by simply applying the classname and the method sel like "ClassName" and "SEL" and then call it dynamically: If it's a class method. then call it like: objc_msgSend(objc_getClass("ClassName"), sel_registerName("SEL")); If it's a instance method, find the existing class instance variable in the calling class then: objc_msgSend([self.classInstance, sel_registerName("SEL")); So I want to know if there is any way to: Check if a class has a given method (I found "responseToSelector" will be the one) Check if a given method in class method or instance method (maybe can use responseToSelector as well) Check if a class has a instance variable of a given class So I can call a instance method like: objc_msgSend(objc_getClassInstance(self, "ClassB"), sel_registerName("SEL"));

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  • sqlobject: No connection has been defined for this thread or process

    - by Claudiu
    I'm using sqlobject in Python. I connect to the database with conn = connectionForURI(connStr) conn.makeConnection() This succeeds, and I can do queries on the connection: g_conn = conn.getConnection() cur = g_conn.cursor() cur.execute(query) res = cur.fetchall() This works as intended. However, I also defined some classes, e.g: class User(SQLObject): class sqlmeta: table = "gui_user" username = StringCol(length=16, alternateID=True) password = StringCol(length=16) balance = FloatCol(default=0) When I try to do a query using the class: User.selectBy(username="foo") I get an exception: ... File "c:\python25\lib\site-packages\SQLObject-0.12.4-py2.5.egg\sqlobject\main.py", line 1371, in selectBy conn = connection or cls._connection File "c:\python25\lib\site-packages\SQLObject-0.12.4-py2.5.egg\sqlobject\dbconnection.py", line 837, in __get__ return self.getConnection() File "c:\python25\lib\site-packages\SQLObject-0.12.4-py2.5.egg\sqlobject\dbconnection.py", line 850, in getConnection "No connection has been defined for this thread " AttributeError: No connection has been defined for this thread or process How do I define a connection for a thread? I just realized I can pass in a connection keyword which I can give conn to to make it work, but how do I get it to work if I weren't to do that?

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  • CakePHP - Paginating an Array

    - by Ashok
    Cake handles pagination of a model with a simple $this-paginate(), but what should I use if I want to paginate a array of values? The Scenario is like this: $this->set('sitepages', $this->paginate()); This code in my index() returns an array like Array ( [0] => Array ( [Sitepage] => Array ( [id] => 13 [name] => Home [urlslug] => home [parent_id] => 1 [page_title] => Welcome to KIAMS, Pune [order] => 1 ) ) [1] => Array ( [Sitepage] => Array ( [id] => 26 [name] => About Us [urlslug] => aboutus [parent_id] => 1 [page_title] => [order] => 2 ) ) [2] => Array ( [Sitepage] => Array ( [id] => 27 [name] => Overview of KIAMS [urlslug] => aboutus/overview [parent_id] => 26 [page_title] => [order] => 2 ) ) I retrieved the same data using $this-Sitepage-find('all') and then performed some manipulations as required and form a array which is very similar to the above one, but the ordering gets changed. I want to paginate this new array and pass it to the view. I tried $this->set('sitepages',$this->paginate($newarray)) But the data is not getting paginated. Can some one please help with paginating the $newarray in CakePHP?

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  • PHP Error Form - Leave Contents of Form on Redirect

    - by user1371500
    I have a simple login form in which if an error occurs such as wrong password, I need it to be able to remember the username which was entered. Would I Go about doing this PHP or Javascript as I am not allowed to use JQuery. My current PHP - (Not Including the HTML Form) <?php //MySQl Connection mysql_connect("localhost", "root", "") or die(mysql_error()); mysql_select_db("clubresults") or die(mysql_error()); //Initiates New Session - Cookie session_start(); // Start a new session // Get the data passed from the form $username = $_POST['username']; $password = md5($_POST['pass']); // Do some basic sanitizing $username = mysql_real_escape_string($username); $password = mysql_real_escape_string($password); //Performs SQL Query to retrieve Login Details from DB $sql = "select * from admin_passwords where username = '$username' and password = '$password'"; $result = mysql_query($sql) or die ( mysql_error() ); //Assigns a Variable Count to 0 $count = 0; //Exectues a loop to increment on Successful Login while ($line = mysql_fetch_assoc($result)) { $count++; } //If count is equal to 1 Redirect user to the Members Page and Set Cookie if ($count == 1) { $_SESSION['loggedIn'] = "true"; header("Location: members.php"); // This is wherever you want to redirect the user to } else { //Else Echo that login was a failure. die('Login Failed. <a href=login.php>Click Here to Try Again</a>'); } ?> Any help would be appreciated. Cheers

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  • Pitfalls of the Architecture - Database based HTTP Request/Response Parsing

    - by Sam
    We have a current eCommerce Site that runs on ASP.NET and we hired a consultant to develop an new site bases on SOA. The new site architecture is as follows Web Application : Single Page Web Application (built on javascript/jquery templates - do not use any MVVM frameworks) that uses some javascript thrown all over the place. Service Layer : Very very light Service Layer that does not do anything other than calling a single stored procedure and pass in the entire http request. Database : The entire site content is in the database. The database does the heavy lifting of parsing the request and based on the HTTP method and some input parameter calls the appropriate Store Procedures or views and renders the result in JSON/XML. We have been told by them that this is built on latest and greatest technologies. I have a lot of concerns and of them given are the few Load on the Database SEO concerns for single page application as this is a public facing website Scalablity? Is this SOA? Cross Browser compatability (Site does not work in < IE9) Realistic implementaion of Single page application I know something is not right but I just need to validate my concerns here. Please help me.

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  • JDBC with JSP fails to insert

    - by StrykeR
    I am having some issues right now with JDBC in JSP. I am trying to insert username/pass ext into my MySQL DB. I am not getting any error or exception, however nothing is being inserted into my DB either. Below is my code, any help would be greatly appreciated. <% String uname=request.getParameter("userName"); String pword=request.getParameter("passWord"); String fname=request.getParameter("firstName"); String lname=request.getParameter("lastName"); String email=request.getParameter("emailAddress"); %> <% try{ String dbURL = "jdbc:mysql:localhost:3306/assi1"; String user = "root"; String pwd = "password"; String driver = "com.mysql.jdbc.Driver"; String query = "USE Users"+"INSERT INTO User (UserName, UserPass, FirstName, LastName, EmailAddress) " + "VALUES ('"+uname+"','"+pword+"','"+fname+"','"+lname+"','"+email+"')"; Class.forName(driver); Connection conn = DriverManager.getConnection(dbURL, user, pwd); Statement statement = conn.createStatement(); statement.executeUpdate(query); out.println("Data is successfully inserted!"); } catch(SQLException e){ for (Throwable t : e) t.printStackTrace(); } %> DB script here: CREATE DATABASE Users; use Users; CREATE TABLE User ( UserID INT NOT NULL AUTO_INCREMENT, UserName VARCHAR(20), UserPass VARCHAR(20), FirstName VARCHAR(30), LastName VARCHAR(35), EmailAddress VARCHAR(50), PRIMARY KEY (UserID) );

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  • C++: Conceptual problem in designing an intepreter

    - by sub
    I'm programming an interpreter for an experimental programming language (educational, fun,...) So far, everything went well (Tokenizer & Parser), but I'm getting a huge problem with some of the data structures in the part that actually runs the tokenized and parsed code. My programming language basically has only two types, int and string, and they are represented as C++ strings (std class) and ints Here is a short version of the data structure that I use to pass values around: enum DataType { Null, Int, String } class Symbol { public: string identifier; DataType type; string stringValue; int intValue; } I can't use union because string doesn't allow me to. This structure above is beginning to give me a headache. I have to scatter code like this everywhere in order to make it work, it is beginning to grow unmaintainable: if( mySymbol.type == Int ) { mySymbol.intValue = 1234; } else { mySymbol.stringValue = "abcde"; } I use the Symbol data structure for variables, return values for functions and general representation of values in the programming language. Is there any better way to solve this? I hope so!

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  • JQuery/AJAX: Loading external DIVs using dynamic content

    - by ticallian
    I need to create a page that will load divs from an external page using Jquery and AJAX. I have come across a few good tutorials, but they are all based on static content, my links and content are generated by PHP. The main tutorial I am basing my code on is from: http://yensdesign.com/2008/12/how-to-load-content-via-ajax-in-jquery/ The exact function i need is as follows: Main page contains a permanent div listing some links containing a parameter. Upon click, link passes parameter to external page. External page filters recordset against parameter and populates div with results. The new div contains a new set of links with new parameters. The external div is loaded underneath the main pages first div. Process can then be repeated creating a chain of divs under each other. The last div in the chain will then direct to a new page collating all the previously used querystrings. I can handle all of the PHP work with populating the divs on the main and external pages. It's the JQuery and AJAX part i'm struggling with. $(document).ready(function(){ var sections = $('a[id^=link_]'); // Link that passes parameter to external page var content = $('div[id^=content_]'); // Where external div is loaded to sections.click(function(){ //load selected section switch(this.id){ case "div01": content.load("external.php?param=1 #section_div01"); break; case "div02": content.load("external.php?param=2 #section_div02"); break; } }); The problem I am having is getting JQuery to pass the dynamically generated parameters to the external page and then retrieve the new div. I can currently only do this with static links (As above).

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  • Passing array of pointers to another class

    - by user310153
    Hi, I am trying to do the following: in main.cpp: // Create an array of pointers to Block objects Block *blk[64]; for (i=0; i<8; i++) { for (j=0; j<8; j++) { int x_low = i*80; int y_low = j*45; blk[j*8+i] = new Block(30, x_low+40.0f, y_low+7.5f, &b); } } And then I am trying to pass it to the graphics object I have created: Graphics g(640, 480, &b, &p, blk[0], number_of_blocks); the graphics constructor looks like: Graphics::Graphics(int width, int height, Ball *b, Paddle *p, Block *blk, int number_of_blocks) { if I look at what is contained in the array from the graphics object, only the first item exists and then all the other items are in hyperspace: for (int i=0; i<64; i++) { printf("for block %d, %f, %f ", i, (_blk+(sizeof(_blk)*i))->_x_low, (_blk+(sizeof(_blk)*i))->_y_low); printf("blah %d\n", (_blk+(sizeof(_blk)*i))); } and if I look at the addresses, they are different (6956552 rather than 2280520 when I examine the addresses in the main class using: printf(" blah %d\n", &blk[j*8*i]); I am sure there must be something subtle I am doing wrong as its like I have copied the first item from the blk array to a new address when passed to the graphics object. Does this make sense? Any ideas? Cheers, Scott

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  • how do I use an enum value on a switch statement in C++

    - by BotBotPgm
    I would like to use an enum value for my switch statment in C++. Is it possible to use the enum values enclosed in the "{}" as choices for the "switch()"? I know that switch() needs an integer value in order to direct the flow of programming to the appropriate case number. If this is the case, do I just make a variable for each constant in the 'enum' statment? I also want the user to be able to pick the choice and pass that choice to the switch() statement. for example: cout<< "1 - Easy"; cout<<"2 - Medium"; cout<< "3 -Hard"; enum myChoice {EASY =1 ,MEDIUM = 2, HARD = 3} cin ???? switch(????) case 1/EASY: (can I just type case EAST?) cout << "You picked easy!"; break; case 2/MEDIUM: cout << "You picked medium!"; case 3..... (same thing as case 2 except on hard.) default: return 0; Thanks

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  • Export to csv, string w/ comma in it, splits it up

    - by Brad
    This code exports data into a csv file, which is opened within Excel. When a string has a comma within it, it messes up the order of the data. I need help modifying my code below to resolve any data that contains a comma within it, to not to create a new column. I am assuming it will pass each string within double quotes, so any comma within those quotes, then it will make an exception. Any help is appreciated. $result = mysql_query("select lname, fname, email, dtelephone, etelephone, contactwhen, comments, thursday, friday, saturday, sunday, monday FROM volunteers_2010"); $csv_output .= "Last Name,First Name,Email,Telephone (Day),Telephone (Evening),Contact When,Comments,Thursday,Friday,Saturday,Sunday,Monday,Comments\n"; $i = 0; if (mysql_num_rows($result) > 0) { while ($row = mysql_fetch_assoc($result)) { $csv_output .= $row['Field'].", "; $i++; } } $csv_output .= "\n"; $values = mysql_query("SELECT lname, fname, email, dtelephone, etelephone, contactwhen, comments, thursday, friday, saturday, sunday, monday FROM volunteers_2010 WHERE venue_id = $venue_id"); while ($rowr = mysql_fetch_row($values)) { for ($j=0;$j<$i;$j++) { $csv_output .= $rowr[$j].", "; } $csv_output .= "\n"; }

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  • Delphi static method of a class returning property value

    - by mitko.berbatov
    I'm making a Delphi VCL application. There is a class TStudent where I have two static functions: one which returns last name from an array of TStudent and another one which returns the first name of the student. Their code is something like: class function TStudent.FirstNameOf(aLastName: string): string; var i : integer; begin for i := 0 to Length(studentsArray) - 1 do begin if studentsArray[i].LastName = aLastName then begin result := studentsArray[i].FirstName; Exit; end; end; result := 'no match was found'; end; class function TStudent.LastNameOf(aFirstName: string): string; var i : integer; begin for i := 0 to Length(studentsArray) - 1 do begin if studentsArray[i].FirstName = aFirstName then begin result := studentsArray[i].LastName; Exit; end; end; result := 'no match was found'; end; My question is how can I avoid writing almost same code twice. Is there any way to pass the property as parameter of the functions.

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  • How costly performance-wise are these actions in iPhone objective-C?

    - by Alex Gosselin
    This is really a few questions in one, I'm wondering what the performance cost is for these things, as I haven't really been following a best practice of any sort for these. The answers may also be useful to other readers, if somebody knows these. (1) If I need the core data managed object context, is it bad to use #import "myAppDelegate.h" //farther down in the code: NSManagedObjectContext *context = [(myAppDelegate.h*)[[UIApplication sharedApplication] delegate] managedObjectContext]; as opposed to leaving the warning you get if you don't cast the delegate? (2) What is the cheapest way to hard-code a string? I have been using return @"myString"; on occasion in some functions where I need to pass it to a variety of places, is it better to do it this way: static NSString *str = @"myString"; return str; (3) How costly is it to subclass an object i wrote vs. making a new one, in general? (4) When I am using core data and navigating through a hierarchy of some sort, is it necessary to turn things back into faults somehow after I read some info from them? or is this done automatically? Thanks for any help.

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  • how to fetch data from Plist in Label

    - by SameSung Vs Iphone
    I have a RegistrationController screen to store email-id ,password,DOB,Height,Weight and logininController screen to match email-id and password to log-in purpose. Now In some third screen I have to fetch only the Height,Weight from the plist of the logged-in user to display it on the label.now if I Store the values of email-id and password in from LoginViewController in string and call it in the new screen to match if matches then gives Height,Weight ..if it corrects then how to fetch Height,Weight from the plist of the same one. how can i fetch from the stored plist in a string... the code which i used to match in LoginController -(NSArray*)readFromPlist { NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [documentPaths objectAtIndex:0]; NSString *documentPlistPath = [documentsDirectory stringByAppendingPathComponent:@"XYZ.plist"]; NSDictionary *dict = [NSDictionary dictionaryWithContentsOfFile:documentPlistPath]; NSArray *valueArray = [dict objectForKey:@"title"]; return valueArray; } - (void)authenticateCredentials { NSMutableArray *plistArray = [NSMutableArray arrayWithArray:[self readFromPlist]]; for (int i = 0; i< [plistArray count]; i++) { id object = [plistArray objectAtIndex:i]; if ([object isKindOfClass:[NSDictionary class]]) { NSDictionary *objDict = (NSDictionary *)object; if ([[objDict objectForKey:@"pass"] isEqualToString:emailTextFeild.text] && [[objDict objectForKey:@"title"] isEqualToString:passwordTextFeild.text]) { NSLog(@"Correct credentials"); return; } NSLog(@"INCorrect credentials"); } else { NSLog(@"Error! Not a dictionary"); } } }

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  • How to implement instance numbering?

    - by Joan Venge
    I don't know if the title is clear but basically I am trying to implement something like this: public class Effect { public int InternalId ... public void ResetName() ... } When ResetName is called, this will reset the name of the object to: "Effect " + someIndex; So if I have 5 instances of Effect, they will be renamed to: "Effect 1" "Effect 2" "Effect 3" ... So I have another method (ResetNames) in another manager/container type that calls ResetName for each instance. And right now I have to pass an integer to ResetName while keeping a counter myself inside ResetNames. But this feels not as clean and this prevents me from calling ResetName myself outside the manager class, which is valid. How to do this better/cleaner? As for the InternalId, it's just some id that stores the creation order for everything. So I can't just rely on these, because the numbers are large, like 32000, etc. EDIT: Container ResetNames code: int count = 1; var effects = this.Effects.OrderBy ( n => n.InternalId ); foreach ( Effect effect in effects ) { effect.ResetName ( count ); ++count; }

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  • Python threading question (Working with a method that blocks forever)

    - by Nix
    I am trying to wrap a thread around some receiving logic in python. Basically we have an app, that will have a thread in the background polling for messages, the problem I ran into is that piece that actually pulls the messages waits forever for a message. Making it impossible to terminate... I ended up wrapping the pull in another thread, but I wanted to make sure there wasn't a better way to do it. Original code: class Manager: def __init__(self): receiver = MessageReceiver() receiver.start() #do other stuff... class MessageReceiver(Thread): receiver = Receiver() def __init__(self): Thread.__init__(self) def run(self): #stop is a flag that i use to stop the thread... while(not stopped ): #can never stop because pull below blocks message = receiver.pull() print "Message" + message What I refectored to: class Manager: def __init__(self): receiver = MessageReceiver() receiver.start() class MessageReceiver(Thread): receiver = Receiver() def __init__(self): Thread.__init__(self) def run(self): pullThread = PullThread(self.receiver) pullThread.start() #stop is a flag that i use to stop the thread... while(not stopped and pullThread.last_message ==None): pass message = pullThread.last_message print "Message" + message class PullThread(Thread): last_message = None def __init__(self, receiver): Thread.__init(self, target=get_message, args=(receiver)) def get_message(self, receiver): self.last_message = None self.last_message = receiver.pull() return self.last_message I know the obvious locking issues exist, but is this the appropriate way to control a receive thread that waits forever for a message? One thing I did notice was this thing eats 100% cpu while waiting for a message... **If you need to see the stopping logic please let me know and I will post.

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  • What does the Asterisk * mean in Objective-C?

    - by Thanks
    Is it true, that the Asterisk always means "Hey, that is a pointer!" And an Pointer always holds an memory adress? (Yes I know for the exception that a * is used for math operation) For Example: NSString* myString; or SomeClass* thatClass; or (*somePointerToAStruct).myStructComponent = 5; I feel that there is more I need to know about the Asterirsk (*) than that I use it when defining an Variable that is a pointer to a class. Because sometimes I already say in the declaration of an parameter that the Parameter variable is a pointer, and still I have to use the Asterisk in front of the Variable in order to access the value. That recently happened after I wanted to pass a pointer of an struct to a method in a way like [myObj myMethod:&myStruct], I could not access a component value from that structure even though my method declaration already said that there is a parameter (DemoStruct*)myVar which indeed should be already known as a pointer to that demostruct, still I had always to say: "Man, compiler. Listen! It IIISSS a pointer:" and write: (*myVar).myStructComponentX = 5; I really really really do not understand why I have to say that twice. And only in this case. When I use the Asterisk in context of an NSString* myString then I can just access myString however I like, without telling the compiler each time that it's a pointer. i.e. like using *myString = @"yep". It just makes no sense to me.

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  • C++ const-reference semantics?

    - by Kristoffer
    Consider the sample application below. It demonstrates what I would call a flawed class design. #include <iostream> using namespace std; struct B { B() : m_value(1) {} long m_value; }; struct A { const B& GetB() const { return m_B; } void Foo(const B &b) { // assert(this != &b); m_B.m_value += b.m_value; m_B.m_value += b.m_value; } protected: B m_B; }; int main(int argc, char* argv[]) { A a; cout << "Original value: " << a.GetB().m_value << endl; cout << "Expected value: 3" << endl; a.Foo(a.GetB()); cout << "Actual value: " << a.GetB().m_value << endl; return 0; } Output: Original value: 1 Expected value: 3 Actual value: 4 Obviously, the programmer is fooled by the constness of b. By mistake b points to this, which yields the undesired behavior. My question: What const-rules should you follow when designing getters/setters? My suggestion: Never return a reference to a member variable if it can be set by reference through a member function. Hence, either return by value or pass parameters by value. (Modern compilers will optimize away the extra copy anyway.)

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  • Sharing class member data between sub components

    - by Tim Gradwell
    I have an aggregate 'main' class which contains some data which I wish to share. The main class also has other class members. I want to share the data with these other class members. What is the correct / neatest way to do this? The specific example I have is as follows. The main class is a .net Form. I have some controls (actually controls within controls) on the main form which need access to the shared data. Main Form - DataX - DataY - Control1 -- Subcontrol1 - Control2 -- SubControl2 SubControls 1 and 2 both wish to access DataX and DataY. The trouble is, I feel like better practice (to reduce coupling), would be that either subcontrols should not know about Main Form, or Main Form should not know about subcontrols - probably the former. For subcontrols not to know about Main Form, would probably mean Main Form passing references to both Controls 1 and 2, which in turn would pass the references on to SubControls 1 and 2. Lots of lines of code which just forward the references. If I later added DataZ and DataW, and Controls 3 and 4 and SubControls 3 and 4, I'd have to add lots more reference forwarding code. It seems simpler to me to give SubControls 1 and 2 member references to Main Form. That way, any sub control could just ask for MainForm.DataX or MainForm.DataY and if I ever added new data, I could just access it directly from the sub controls with no hassle. But it still involves setting the 'MainForm' member references every time I add a new Control or Subcontrol. And it gives me a gut feeling of 'wrong'. As you might be able to tell I'm not happy with either of my solutions. Is there a better way? Thanks

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  • How to use the values from session variables in jsp pages that got saved using @Scope("session") in the mvc controllers

    - by droidsites
    Doing a web site using spring mvc. I added a SignupController to handle all the sign up related requests. Once user signup I am adding that to a session using @Scope("session"). Below is the SignupController code, SignupController.java @Controller @Scope("session") public class SignupController { @Autowired SignupServiceInter signUpService; private static final Logger logger = Logger.getLogger(SignupController.class); private String sessionUser; @RequestMapping("/SignupService") public ModelAndView signUp(@RequestParam("userid") String userId, @RequestParam("password") String password,@RequestParam("mailid") String emailId){ logger.debug(" userId:"+userId+"::Password::"+password+"::"); String signupResult; try { signUpService.registerUser(userId, password,emailId); sessionUser = userId; //adding the sign up user to the session return new ModelAndView("userHomePage","loginResult","Success"); //Navigate to user Home page if everything goes right } catch (UserExistsException e) { signupResult = e.toString(); return new ModelAndView("signUp","loginResult", signupResult); //Navigate to signUp page back if user does not exist } } } I am using "sessionUser" variable to store the signed up User Id. My understanding is that when I use @Scope("session") for the controller all the instance variables will added to HttpSession. So by that understanding I tried to access this "SessionUser" in userHomePage.jsp as, userHomepage.jsp Welcome to <%=session.getAttribute("sessionUser")%> But it throws null. So my question is how to use the values from session variables in jsp pages that got saved using @Scope("session") in the mvc controllers. Note: My work around is that pass that signed User Id to jsp page through ModelAndView, but it seems passing the value like these among the pages takes me back to managing state among pages using QueryStrings days.

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  • Calling a register method from 2 or more controllers best practice

    - by PussInBoots
    I don't want to repeat myself. That is, I don't want the same code in two different controllers. I always start from a default mvc5 web app project. That project has a Register ActionMethod in an AccountController: // // GET: /Account/Register [AllowAnonymous] public ActionResult Register() { return View(); } // // POST: /Account/Register [HttpPost] [AllowAnonymous] [ValidateAntiForgeryToken] public async Task<ActionResult> Register(RegisterViewModel model) { if (ModelState.IsValid) { var user = new ApplicationUser() { UserName = model.UserName }; var result = await UserManager.CreateAsync(user, model.Password); if (result.Succeeded) { await SignInAsync(user, isPersistent: false); return RedirectToAction("Index", "Home"); } else { AddErrors(result); } } // If we got this far, something failed, redisplay form return View(model); } Say I have a CampaignController and I want to register a user when he/she is on that page, fills out his/her username and pass and clicks the send form/submit button. What is the best thing to do in the ActionMethod of that form/controller? Yes, I want to have the registerform in two or more places. What is the best way to accomplish this in mvc 5?

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  • Should I re-use UI elements across view controllers?

    - by Endemic
    In the iPhone app I'm currently working on, I'd like two navigation controllers (I'll call them A and B) to have toolbars that are identical in appearance and function. The toolbar in question will look like this: [(button) (flexible-space) (label)] For posterity's sake, the label is actually a UIBarButtonItem with a custom view. My design requires that A always appear directly before B on the navigation stack, so B will never be loaded without A having been loaded. Given this layout, I started wondering, "Is it worth it to re-use A's toolbar items in B's toolbar?" As I see it, my options are: 1. Don't worry about re-use, create the toolbar items twice 2. Create the toolbar items in A and pass them to B in a custom initializer 3. Use some more obscure method that I haven't thought of to hold the toolbar constant when pushing a view controller As far as I can see, option 1 may violate DRY, but guarantees that there won't be any confusion on the off chance that (for example) the button may be required to perform two different (no matter how similar) functions for either view controller in future versions of the app. Were that to happen, options 2 or 3 would require the target-action of the button to change when B is loaded and unloaded. Even if the button were never required to perform different functions, I'm not sure what its proper target would be under option 2. All in all, it's not a huge problem, even if I have to go with option 1. I'm probably overthinking this anyway, trying to apply the dependency injection pattern where it's not appropriate. I just want to know the best practice should this situation arise in a more extreme form, like if a long chain of view controllers need to use identical (in appearance and function) UI elements.

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