Search Results

Search found 15630 results on 626 pages for 'variable variables'.

Page 554/626 | < Previous Page | 550 551 552 553 554 555 556 557 558 559 560 561  | Next Page >

  • jQuery: If, Else with buttons error

    - by Wipqozn
    I'm running into an odd error. I'm working in Django 1.2, and have implemented the commenting framework. I'm trying to attach a hide/show button to each comment field, but whenever click on a hide/show button, it behaves as if each hide/show button beneath it on the page was clicked. Here's the jQuery code: <input type="Button" id="hideShow" name="hide/show" value="Hide"></input> <script> $("#hideShow").click(function() { if($(this).val() == "Hide") { $("textarea").hide("fast"); $(this).val("Show"); } else { $("textarea").show("fast"); $(this).val( "Hide"); } }); </script> So, when I click the Hide/show button, it will perform the action for each button beneath the clicked button + once for the button itself. So If I click a button, and there are two buttons beneath it, and value=hide it will first hide the 'textarea', than show the text area, than finally hide it again. I'm new to jQuery (although I do have experience in other languages), and I have an -idea- why it's not working: that whenever an action is performed jQuery jumps to the first one, than continues down the page looking for any other actions performed, and responds to each one. So it comes to my first button, sets it as being clicked, and so when jQuery comes across the other buttons it views them all as being 'clicked' and performs actions accordingly. I've thought of a semi-solution to my problem, putting in a variable which tracks how many times it has gone through, and than acting based on -that- action. But I would rather not do that, since it's not really a solution to the problem at hand but a work around. Any input is appreciated.

    Read the article

  • Beginner PHP: I can't insert data into MYSQL database

    - by Victor
    I'm learning PHP right now and I'm trying to insert data into a MySQL database called "pumpl2" The table is set up like this. create table product ( productid int unsigned not null auto_increment primary key, price int(9) not null, value int(9) not null, description text ); I have a form and want to insert the fields from the form in the database. Here is what the php file looks like. <?php // create short variable names $price = $_POST['price']; $value = $_POST['value']; $description = $_POST['description']; if (!$price || !$value || !$description) { echo "You have not entered all the required details.<br />" ."Please go back and try again."; exit; } @ $db = new mysqli('localhost', 'pumpl', '********', 'pumpl2'); if (mysqli_connect_errno()) { echo "Error: Could not connect to database. Please try again later."; exit; } $query = "insert into pumpl2 values ('".$price."', '".$value."', '".$description."')"; $result = $db->query($query); if ($result) { echo $db->affected_rows." product inserted into database."; } else { echo "An error has occurred. The item was not added."; } $db->close(); ?> When I submit the form, I get an error message "An error has occurred. The item was not added." Does anyone know what the problem is? Thank you!

    Read the article

  • How to understand "if ( obj.length === +obj.length )" Javascript condition statement?

    - by humanityANDpeace
    I have run across a condition statement which I have some difficulties to understand. It looks like (please note the +-sign on the right-hand-side) this: obj.length === +obj.length. Can this condition and its purpose/syntax be explained? Looking at the statement (without knowing it) provokes the impression that it is a dirty hack of some sort, but I am almost certain that underscore.js is rather a well designed library, so there must be a better explanation. Background I found this statement used in some functions of the underscore.js library (underscore.js annotated source). My guesswork is that this condition statement is somehow related to testing for a variable obj to be of Array type? (but I am totally unsure). I have tried to test this using this code. var myArray = [1,2,3]; testResult1 = myArray.length === +myArray.length; console.log( testResult1 ); //prints true var myObject = { foo : "somestring", bar : 123 }; testResult2 = myObject.length === +myObject.length; console.log( testResult2 ); //prints false

    Read the article

  • How can I build a generic dataset-handling Perl library?

    - by Pep.
    Hello, I want to build a generic Perl module for handling and analysing biomedical character separated datasets and which can, most certain, be used on any kind of datasets that contain a mixture of categorical (A,B,C,..) and continuous (1.2,3,881..) and identifier (XXX1,XXX2...). The plan is to have people initialize the module and then use some arguments to point to the data file(s), the place were the analysis reports should be placed and the structure of the data. By structure of data I mean which variable is in which place and its name/type. And this is where I need some enlightenment. I am baffled how to do this in a clean way. Obviously, having people create a simple schema file, be it XML or some other format would be the cleanest but maybe not all people enjoy doing something like this. The solutions I can think of are: Create a configuration file in XML or similar and with a prespecified format. Pass the information during initialization of the module. Use the first row of the data as headers and try to guess types (ouch) Surely there must be a "canonical" way of doing this that is also usable and efficient. Thanks p.

    Read the article

  • php cURL. preg_match , extract text from xhtml

    - by Michael
    I'm trying to extract the price from the bellow html page/link using php cURL and preg_match . Basically I'm expecting for this code to output 4,550 but for some reasons I get Notice: Undefined offset: 1 in C:\wamp\www\test.php on line 22 I think that the pattern is correct because if I put the html itself in a variable and escape the "" it works ! . Also if I output (echo $result;) it displays the html properly grabbed from foxtons website so I just can't figure it out why the whole thing doesn't work . I need to make this work and also I would appreciate if you would tell me why is that notice generated and why my current script doesn't work. $url = "http://www.foxtons.co.uk/search?bedrooms_from=0&property_id=727717"; $ch = curl_init($url); curl_setopt($ch, CURLOPT_HEADER, 0); curl_setopt($ch,CURLOPT_RETURNTRANSFER, 1); $result = curl_exec($ch); curl_exec($ch); curl_close($ch); $result2 = str_replace('"', '\"', $result); $tagname1= ");<\/script "; $tagname2= "<\/noscript per month<\/a"; $pattern = "/$tagname1(.*?)$tagname2/"; preg_match($pattern, $result, $matches); $prices = $matches[1]; print_r($prices); ?

    Read the article

  • controlling css with javascript works with mozilla but not with webkit based browsers

    - by GlassGhost
    Im having problems with applying css text variable in this javascript with webkit based browsers(Chrome & Safari) but it works in firefox 3.6 the function: function addGlobalStyle(sCss) { var head = document.getElementsByTagName('head')[0]; if( !head || head == null ) { return false; } var oStyle = document.createElement('style'); oStyle.type = 'text/css'; oStyle.rel = 'stylesheet'; oStyle.media = 'screen'; if ( is_gecko ) { // firefox WORKING !!! oStyle.href = 'FireFox.css'; oStyle.innerHTML = sCss; head.appendChild(oStyle); return true; } else {//nothing but firefox works oStyle.href = 'FireFox.css'; oStyle.innerHTML = sCss; head.appendChild(oStyle); return true; } } the use of the function: var NewSyleText = //The page styling "h1, h2, h3, h4, h5 {font-family: 'Verdana','Helvetica',sans-serif; font-style: normal; font-weight:normal;}" + "body, b {background: #fbfbfb; font-style: normal; font-family: 'Cochin','GaramondNo8','Garamond','Big Caslon','Georgia','Times',serif;font-size: 11pt;}" + "p { margin: 0pt; text-indent:2.5em; margin-top: 0.3em; }" + "a { text-decoration: none; color: Navy; background: none;}" + "a:visited { color: #500050;}" + "a:active { color: #faa700;}" + "a:hover { text-decoration: underline;}"; addGlobalStyle(NewSyleText);//inserts the page styling

    Read the article

  • Help dealing with data dependency between two registration forms

    - by franko75
    I have a tricky issue here with a registration of both a user and his/her pet. Both the user and the pet are treated as separate entities and both require separate registration forms. However, the user's pet has to be linked to the user via a foreign key in the database. The process is basically that when a new user joins the site, firstly they register their pet, then they register themselves. The reason for this order is to check their pet's eligibility for the site (there are some criteria to be met) first, instead of getting the user to sign up only to then find out their pet is ineligible. It is this ordering of the form submissions which is causing me a bit of a headache, as follows... The site is being developed with an MVC framework, and the User registration process is managed via a method in a User_form controller, while the pet registration process is managed via a method in the Pet_form controller. The pet registration form happens first, and the pet data can be saved without the owner_id at this stage, with the user id possibly being added (e.g by retrieving pet's id from session) following user registration. However, doing it this way could potentially result in redundant data, where pet records would be created in the database, but if the user doesn't actually register themselves too, then the pets will be ownerless records in the DB. Other option is to serialize the new pet's data at the pet registration stage, don't save it to the DB until the user fills out their registration form. Once the user is created, i can pass serialised data AND the owner_id to a method in the Pet Model which can update the DB. However, I also need to set the newly created $pet to $this-pet which I then access for a sequence of other related forms. Should I just set the session variable in the model method? Then in the Pet controller constructor, do a check for pet stored in session, if yes, assign to $this-pet... If this makes any sense to anybody and you have some advice, i'd be grateful to hear it!

    Read the article

  • Modifying bundled properties from visitor

    - by ravenspoint
    How should I modify the bundled properties of a vertex from inside a visitor? I would like to use the simple method of sub-scripting the graph, but the graph parameter passed into the visitor is const, so compiler disallows changes. I can store a reference to the graph in the visitor, but this seems weird. /** A visitor which identifies vertices as leafs or trees */ class bfs_vis_leaf_finder:public default_bfs_visitor { public: /** Constructor @param[in] total reference to int variable to store total number of leaves @param[in] g reference to graph ( used to modify bundled properties ) */ bfs_vis_leaf_finder( int& total, graph_t& g ) : myTotal( total ), myGraph( g ) { myTotal = 0; } /** Called when the search finds a new vertex If the vertex has no children, it is a leaf and the total leaf count is incremented */ template <typename Vertex, typename Graph> void discover_vertex( Vertex u, Graph& g) { if( out_edges( u, g ).first == out_edges( u, g ).second ) { myTotal++; //g[u].myLevel = s3d::cV::leaf; myGraph[u].myLevel = s3d::cV::leaf; } else { //g[u].myLevel = s3d::cV::tree; myGraph[u].myLevel = s3d::cV::tree; } } int& myTotal; graph_t& myGraph; };

    Read the article

  • Can I use drawRect to refresh a UIView subclass?

    - by Timbo
    I've created a subclass of UIView called Status which is designed to display a rectangle of a certain size (within a view) depending on the value of a variable. // Interface #import <Foundation/Foundation.h> #import <QuartzCore/QuartzCore.h> @interface Status: UIView { NSString* name; int someVariable; } @property int someVariable; @property (assign) NSString *name; - (void) createStatus: (NSString*)withName; - (void) drawRect:(CGRect)rect; @end // Implementation #import "Status.h" @implementation Status @synthesize name, someVariable; - (void) createStatus: (NSString*)withName { name = withName; someVariable = 10000; } - (void) drawRect:(CGRect)rect { CGContextRef context = UIGraphicsGetCurrentContext(); //Draw Status CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1); // fill CGContextFillRect(context, CGRectMake(0.0, 0.0, someVariable, 40.0)); } //// myviewcontroller implementation - (void) viewDidAppear:(BOOL)animated { [super viewDidAppear:animated]; myStatus = [[Status alloc] initWithFrame:CGRectMake(8,8,200,56)]; myStatus.backgroundColor = [UIColor grayColor]; [self.view addSubview:myStatus]; } How do I set this up so I can repeatedly call a refresh of the status bar? I'll probably call the refresh 4 times per second using a NSTimer, I'm just not sure what to call or if I should move this rectangle drawing to a separate function or something... Thanks in advance for your help :)

    Read the article

  • C/C++ macro/template blackmagic to generate unique name.

    - by anon
    Macros are fine. Templates are fine. Pretty much whatever it works is fine. The example is OpenGL; but the technique is C++ specific and relies on no knowledge of OpenGL. Precise problem: I want an expression E; where I do not have to specify a unique name; such that a constructor is called where E is defined, and a destructor is called where the block E is in ends. For example, consider: class GlTranslate { GLTranslate(float x, float y, float z); { glPushMatrix(); glTranslatef(x, y, z); } ~GlTranslate() { glPopMatrix(); } }; Manual solution: { GlTranslate foo(1.0, 0.0, 0.0); // I had ti give it a name ..... } // auto popmatrix Now, I have this not only for glTranslate, but lots of other PushAttrib/PopAttrib calls too. I would prefer not to have to come up with a unique name for each var. Is there some trick involving macros templates ... or something else that will automatically create a variable who's constructor is called at point of definition; and destructor called at end of block? Thanks!

    Read the article

  • optimize output value using a class and public member

    - by wiso
    Suppose you have a function, and you call it a lot of times, every time the function return a big object. I've optimized the problem using a functor that return void, and store the returning value in a public member: #include <vector> const int N = 100; std::vector<double> fun(const std::vector<double> & v, const int n) { std::vector<double> output = v; output[n] *= output[n]; return output; } class F { public: F() : output(N) {}; std::vector<double> output; void operator()(const std::vector<double> & v, const int n) { output = v; output[n] *= n; } }; int main() { std::vector<double> start(N,10.); std::vector<double> end(N); double a; // first solution for (unsigned long int i = 0; i != 10000000; ++i) a = fun(start, 2)[3]; // second solution F f; for (unsigned long int i = 0; i != 10000000; ++i) { f(start, 2); a = f.output[3]; } } Yes, I can use inline or optimize in an other way this problem, but here I want to stress on this problem: with the functor I declare and construct the output variable output only one time, using the function I do that every time it is called. The second solution is two time faster than the first with g++ -O1 or g++ -O2. What do you think about it, is it an ugly optimization?

    Read the article

  • Reading from an write-only(OUT) parameter in pl/sql

    - by sqlgrasshopper5
    When I tried writing to an read-only parameter(IN) of a function, Oracle complains with an error. But that is not the case when reading from an write-only(OUT) parameter of a function. Oracle silently allows this without any error. What is the reason for this behaviour?. The following code executes without any assignment happening to "so" variable: create or replace function foo(a OUT number) return number is so number; begin so := a; --no assignment happens here a := 42; dbms_output.put_line('HiYA there'); dbms_output.put_line('VAlue:' || so); return 5; end; / declare somevar number; a number := 6; begin dbms_output.put_line('Before a:'|| a); somevar := foo(a); dbms_output.put_line('After a:' || a); end; / Here's the output I got: Before a:6 HiYA there VAlue: After a:42

    Read the article

  • Java: Tracking a user login session - Session EJBs vs HTTPSession

    - by bguiz
    If I want to keep track of a conversational state with each client using my web application, which is the better alternative - a Session Bean or a HTTP Session - to use? Using HTTP Session: //request is a variable of the class javax.servlet.http.HttpServletRequest //UserState is a POJO HttpSession session = request.getSession(true); UserState state = (UserState)(session.getAttribute("UserState")); if (state == null) { //create default value .. } String uid = state.getUID(); //now do things with the user id Using Session EJB: In the implementation of ServletContextListener registered as a Web Application Listener in WEB-INF/web.xml: //UserState NOT a POJO this this time, it is //the interface of the UserStateBean Stateful Session EJB @EJB private UserState userStateBean; public void contextInitialized(ServletContextEvent sce) { ServletContext servletContext = sce.getServletContext(); servletContext.setAttribute("UserState", userStateBean); ... In a JSP: public void jspInit() { UserState state = (UserState)(getServletContext().getAttribute("UserState")); ... } Elsewhere in the body of the same JSP: String uid = state.getUID(); //now do things with the user id It seems to me that the they are almost the same, with the main difference being that the UserState instance is being transported in the HttpRequest.HttpSession in the former, and in a ServletContext in the case of the latter. Which of the two methods is more robust, and why?

    Read the article

  • In AS3/Flex, how can I get from flat data to hierarchical data?

    - by Dave S
    I have some data that gets pulled out of a database and mapped to an arraycollection. This data has a field called parentid, and I would like to map the data into a new arraycollection with hierarchical information to then feed to an advanced data grid. I think I'm basically trying to take the parent object, add a new property/field/variable of type ArrayCollection called children and then remove the child object from the original list and clone it into the children array? Any help would be greatly appreciated, and I apologize ahead of time for this code: private function PutChildrenWithParents(accountData : ArrayCollection) : ArrayCollection{ var pos_inner:int = 0; var pos_outer:int = 0; while(pos_outer < accountData.length){ if (accountData[pos_outer].ParentId != null){ pos_inner = 0; while(pos_inner < accountData.length){ if (accountData[pos_inner].Id == accountData[pos_outer].ParentId){ accountData.addItemAt( accountData[pos_inner] + {children:new ArrayCollection(accountData[pos_outer])}, pos_inner ); accountData.removeItemAt(pos_outer); accountData.removeItemAt(pos_inner+1); } pos_inner++; } } pos_outer++; } return accountData; }

    Read the article

  • sum of square of each elements in the vector using for_each

    - by pierr
    Hi, As the function accepted by for_each take only one parameter (the element of the vector), I have to define a static int sum = 0 somewhere so that It can be accessed after calling the for_each . I think this is awkward. Any better way to do this (still use for_each) ? #include <algorithm> #include <vector> #include <iostream> using namespace std; static int sum = 0; void add_f(int i ) { sum += i * i; } void test_using_for_each() { int arr[] = {1,2,3,4}; vector<int> a (arr ,arr + sizeof(arr)/sizeof(arr[0])); for_each( a.begin(),a.end(), add_f); cout << "sum of the square of the element is " << sum << endl; } In Ruby, We can do it this way: sum = 0 [1,2,3,4].each { |i| sum += i*i} #local variable can be used in the callback function puts sum #=> 30 Would you please show more examples how for_each is typically used in practical programming (not just print out each element)? Is it possible use for_each simulate 'programming pattern' like map and inject in Ruby (or map /fold in Haskell). #map in ruby >> [1,2,3,4].map {|i| i*i} => [1, 4, 9, 16] #inject in ruby [1, 4, 9, 16].inject(0) {|aac ,i| aac +=i} #=> 30 EDIT: Thank you all. I have learned so much from your replies. We have so many ways to do the same single thing in C++ , which makes it a little bit difficult to learn. But it's interesting :)

    Read the article

  • How to set element value dynamically based on for each loop count

    - by user1515918
    Here is snippet of an xsl file that I am trying to make work. I would like to change value for element request-tot-queries in the header based on loop count in the Body. Your help would be greatly appreciated! <HEADER> <request-tot-queries>$Counter</request-tot-queries> </HEADER> <Body> <xsl:for-each select="//Request/Responses/Pooled/ResidenceHistory/Residencies/Residency"> <count><xsl:variable name="counter" select="position()"/></count> <xsl:if test="DateRange/To/Date[@Type!='Present']"> <subject-query> . . . </subject-query> </xsl:if> </xsl:for-each> </Body>

    Read the article

  • objective-c having issues with an NSDictioary object

    - by Mark
    I have a simple iPhone app that Im learning and I want to have an instance variable called urlLists which is an NSDictionary I have declared it like so: @interface MyViewController : UIViewController <UIPickerViewDataSource, UIPickerViewDelegate>{ IBOutlet UIPickerView *pickerView; NSMutableArray *categories; NSDictionary *urlLists; } @property(retain) NSDictionary *urlLists; @end and in the implementation: @implementation MyViewController @synthesize urlLists; ... - (void)viewDidLoad { [super viewDidLoad]; categories = [[NSMutableArray alloc] init]; [categories addObject:@"Sport"]; [categories addObject:@"Entertainment"]; [categories addObject:@"Technology"]; [categories addObject:@"Political"]; NSArray *objects = [NSArray arrayWithObjects:@"value1", @"value2", @"value3", @"value4", nil]; urlLists = [NSDictionary dictionaryWithObjects:objects forKeys:categories]; for (id key in urlLists) { NSLog(@"key: %@, value: %@", key, [urlLists objectForKey:key]); } } ... @end And, this all works up to here. I have added a UIPicker to my app, and when I select one of the items, I want to Log the one picked and its related entry in my dictionary. -(void) pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger) component { for (id key in self.urlLists) { NSLog(@"key: %@, value: %@", key, [urlLists objectForKey:key]); } } but I get the old EXC_BAD_ACCESS error... I know Im missing something small, but what? Thanks

    Read the article

  • Matlab GUI: How to Save the Results of Functions (states of application)

    - by niko
    Hi, I would like to create an animation which enables the user to go backward and forward through the steps of simulation. An animation has to simulate the iterative process of channel decoding (a receiver receives a block of bits, performs an operation and then checks if the block corresponds to parity rules. If the block doesn't correspond the operation is performed again and the process finally ends when the code corresponds to a given rules). I have written the functions which perform the decoding process and return a m x n x i matrix where m x n is the block of data and i is the iteration index. So if it takes 3 iterations to decode the data the function returns a m x n x 3 matrix with each step is stired. In the GUI (.fig file) I put a "decode" button which runs the method for decoding and there are buttons "back" and "forward" which have to enable the user to switch between the data of recorded steps. I have stored the "decodedData" matrix and currentStep value as a global variable so by clicking "forward" and "next" buttons the indices have to change and point to appropriate step states. When I tried to debug the application the method returned the decoded data but when I tried to click "back" and "next" the decoded data appeared not to be declared. Does anyone know how is it possible to access (or store) the results of the functions in order to enable the described logic which I want to implement in Matlab GUI?

    Read the article

  • EF in a UserControl can't see the app.config?

    - by Sven
    I just created a user control. This control also makes use of my static Entity Framework class to load two comboboxes. All is well and runs without a problem. Design and runtime are working. Then when I stop the application all the forms that contain my UserControl don't work any more in design time. I just see two errors: Error1: The specified named connection is either not found in the configuration, not intended to be used with the EntityClient provider, or not valid. Error 2: The variable ccArtikelVelden is either undeclared or was never assigned. (ccArtikelVelde is my UserControl) Runtime everything is still working My static EF Repositoy class: public class BSManagerData { private static BSManagerEntities _entities; public static BSManagerEntities Entities { get { if (_entities == null) _entities = new BSManagerEntities(); return _entities; } set { _entities = value; } } } Some logic happening in my UserControl to load the data in the comboboxes: private void LaadCbx() { cbxCategorie.DataSource = (from c in BSManagerData.Entities.Categories select c).ToList(); cbxCategorie.DisplayMember = "Naam"; cbxCategorie.ValueMember = "Id"; } private void cbxCategorie_SelectedIndexChanged(object sender, EventArgs e) { cbxFabrikant.DataSource = from f in BSManagerData.Entities.Fabrikants where f.Categorie.Id == ((Categorie)cbxCategorie.SelectedItem).Id select f; cbxFabrikant.DisplayMember = "Naam"; cbxFabrikant.ValueMember = "Id"; } The only way to make my forms work again, design time, is to comment out the EF part in the UserControl (see above) and rebuild. It's very strange, everything is in the same assembly, same namespace (for the sake of simplicity). Anyone an idea?

    Read the article

  • Saving user settings in Metro app using C#

    - by jitendra garg
    I want to write user selected settings in Metro app, in Local Folder. I have done the code as below, but it is not working. The code to save settings: void OnUnloaded(object sender, RoutedEventArgs args) { //code to save app settings. var localSettings = ApplicationData.Current.LocalSettings; localSettings.Values["playerPosition"] = playerPosition; localSettings.Values["aiPosition"] = aiPosition; localSettings.Values["selectedLevel"] = selectedLevel; } The code to read settings: var localSettings = ApplicationData.Current.LocalSettings; if ((localSettings.Values["playerPosition"]) == null) { localSettings.Values["playerPosition"] = 1; localSettings.Values["aiPosition"] = 1; localSettings.Values["selectedLevel"] = "1"; playerPosition = aiPosition = 1; selectedLevel = "1"; } else { playerPosition = (int)localSettings.Values["playerPosition"]; aiPosition = (int)localSettings.Values["aiPosition"]; selectedLevel = (string)localSettings.Values["selectedLevel"]; ---- Clearly I am supposed to save this localSettings variable in a file. But, I am unable to find the code to do that. Also, is Unload event a good place to do it, or should I move it to OnNavigatedFrom event?

    Read the article

  • iPhone inputting NSUserDefaults into a UITextField

    - by Rob
    I am writing a program where I where the first time a user runs it - they will have to fill out about 10 different UITextFields. I am trying to save the fields so that on subsequent runs of the program that whatever they previously put will already be displayed in those UITextFields so the wont have to re-input it in - unless they want to edit something in which case they still have that option. I think that I have figured out a good way to save the strings using NSUserDefaults but now I am trying to figure out how to have those fields populate a UITextField - it doesnt seem as easy as if they were UILabels. This is the route I am attempting: // in the viewDidLoad portion. NSUserDefaults *userData = [NSUserDefaults standardUserDefaults]; //Hooks. NSString *placeHolderName = [userData stringForKey:@"name"]; txtName.text = @"%@", placeHolderName; When I do this, it simply displays the '%@' in the textfields. I want whatever variable being held by placeHolderName to be automatically put into that UITextField. Is this possible?

    Read the article

  • Changing type of object in a conditional

    - by David Doria
    I'm having a bit of trouble with dynamic_casting. I need to determine at runtime the type of an object. Here is a demo: include include class PersonClass { public: std::string Name; virtual void test(){}; //it is annoying that this has to be here... }; class LawyerClass : public PersonClass { public: void GoToCourt(){}; }; class DoctorClass : public PersonClass { public: void GoToSurgery(){}; }; int main(int argc, char *argv[]) { PersonClass* person = new PersonClass; if(true) { person = dynamic_cast(person); } else { person = dynamic_cast(person); } person-GoToCourt(); return 0; } I would like to do the above. The only legal way I found to do it is to define all of the objects before hand: PersonClass* person = new PersonClass; LawyerClass* lawyer; DoctorClass* doctor; if(true) { lawyer = dynamic_cast(person); } else { doctor = dynamic_cast(person); } if(true) { lawyer-GoToCourt(); } The main problem with this (besides having to define a bunch of objects that won't be use) is that I have to change the name of the 'person' variable. Is there a better way? (I am not allowed to change any of the classes (Person, Lawyer, or Doctor) because they are part of a library that people who will use my code have and won't want to change). Thanks, Dave

    Read the article

  • how can i return a string with jQuery from an input and write it to a different html element

    - by user1865231
    I am using this: var title = $('#input').val(); $('#titleset').click(function (){ $('#title').html('<h1>' + title + '</h1>'); alert(title); }); to try to get the value of an input box and then when the user clicks the button #titleset, overwrite the value from the input box to the <h1> element that is already there. i have been able to get the click to overwrite the <h1> element, but there is nothing in the title variable to write into the element. so how could i return a string from the #input id and write it to the #title id which is an <h1> element here is my html <h1 id="title">This Title Changes To What You Want It To Be</h1> <ul class="menu1"> <li>menu one <ul> <li id='inputbox'><input type ="text" id="input"/></li> <li id="titleset1"><input type="button" value="set title" id="titleset"/></li> </ul> </li> </ul>

    Read the article

  • How to call a generic method with an anonymous type involving generics?

    - by Alex Black
    I've got this code that works: def testTypeSpecialization = { class Foo[T] def add[T](obj: Foo[T]): Foo[T] = obj def addInt[X <% Foo[Int]](obj: X): X = { add(obj) obj } val foo = addInt(new Foo[Int] { def someMethod: String = "Hello world" }) assert(true) } But, I'd like to write it like this: def testTypeSpecialization = { class Foo[T] def add[X, T <% Foo[X](obj: T): T = obj val foo = add(new Foo[Int] { def someMethod: String = "Hello world" }) assert(true) } This second one fails to compile: no implicit argument matching parameter type (Foo[Int]{ ... }) = Foo[Nothing] was found. Basically: I'd like to create a new anonymous class/instance on the fly (e.g. new Foo[Int] { ... } ), and pass it into an "add" method which will add it to a list, and then return it The key thing here is that the variable from "val foo = " I'd like its type to be the anonymous class, not Foo[Int], since it adds methods (someMethod in this example) Any ideas? I think the 2nd one fails because the type Int is being erased. I can apparently 'hint' the compiler like this: def testTypeSpecialization = { class Foo[T] def add[X, T <% Foo[X]](dummy: X, obj: T): T = obj val foo = add(2, new Foo[Int] { def someMethod: String = "Hello world" }) assert(true) }

    Read the article

  • Why is it that an int in C++ that isnt initialized (then used) doesn't return an error?

    - by omizzle
    I am new to C++ (just starting). I come from a Java background and I was trying out the following piece of code that would sum the numbers between 1 and 10 (inclusive) and then print out the sum: /* * File: main.cpp * Author: omarestrella * * Created on June 7, 2010, 8:02 PM */ #include <cstdlib> #include <iostream> using namespace std; int main() { int sum; for(int x = 1; x <= 10; x++) { sum += x; } cout << "The sum is: " << sum << endl; return 0; } When I ran it it kept printing 32822 for the sum. I knew the answer was supposed to be 55 and realized that its print the max value for a short (32767) plus 55. Changing int sum; to int sum = 0; would work (as it should, since the variable needs to be initialized!). Why does this behavior happen, though? Why doesnt the compiler warn you about something like this? I know Java screams at you when something isnt initialized. Thank you.

    Read the article

< Previous Page | 550 551 552 553 554 555 556 557 558 559 560 561  | Next Page >