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  • How to pass a class method as an argument for another function in C++ and openGL?

    - by tsubasa
    I know this thing works: void myDisplay() { ... } int main() { ... glutDisplayFunc(myDisplay) ... } so I tried to include myDisplay() function to a class that I made. Because I want to overload it in the future with a different class. However, the compiler complains that argument of type 'void (ClassBlah::)()' does not match 'void(*)()' . Here is the what I try to make: class ClassBlah { .... void myDisplay() .... } ...... int main() { ... ClassBlah blah glutDisplayFunc(blah.myDisplay) ... } Does anybody knows how to fix this problem? Many thanks.

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  • Javascript private member on prototype...

    - by Wilq32
    Well I tried to figure out is this possible in any way. Here is code: a=function(text) { var b=text; if (!arguments.callee.prototype.get) arguments.callee.prototype.get=function() { return b; } else alert('already created!'); } var c=new a("test"); // creates prototype instance of getter var d=new a("ojoj"); // alerts already created alert(c.get()) // alerts test alert(d.get()) // alerts test from context of creating prototype function :( As you see I tried to create prototype getter. For what? Well if you write something like this: a=function(text) { var b=text; this.getText=function(){ return b} } ... everything should be fine.. but in fact every time I create object - i create getText function that uses memory. I would like to have one prototypical function lying in memory that would do the same... Any ideas? EDIT: I tried solution given by Christoph, and it seems that its only known solution for now. It need to remember id information to retrieve value from context, but whole idea is nice for me :) Id is only one thing to remember, everything else can be stored once in memory. In fact you could store a lot of private members this way, and use anytime only one id. Actually this is satisfying me :) (unless someone got better idea). someFunc = function() { var store = new Array(); var guid=0; var someFunc = function(text) { this.__guid=guid; store[guid++]=text; } someFunc.prototype.getValue=function() { return store[this.__guid]; } return someFunc; }() a=new someFunc("test"); b=new someFunc("test2"); alert(a.getValue()); alert(b.getValue());

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  • Loading the preview function of AUCTeX 11.86 on macports Emacs-app 23.2.1 port.

    - by Sarah
    I've installed Emacs-app 23.2.1 via MacPorts and I'm trying to install AUCTeX 11.86 so that it will work on this installation. I've run the following configure line for AUCTeX and that seems to work. ./configure --with-emacs=/Applications/MacPorts/Emacs.app/Contents/MacOS/Emacs --with-lispdir=/Applications/MacPorts/Emacs.app/Contents/Resources/site-lisp/ --with-texmf-dir=/usr/local/texlive/2010basic/texmf-local/ make and make install seem to work, and I've added the following line to my init.el (require 'tex-site) as per the installation instructions. However, when I open a TeX file, the Preview menu does not show up (although the LaTeX menu does.) The following are some of my tests: M-x load-library RET preview-latex RET doesn't seem to do anything. M-x load-library RET preview RET brings up the Preview menu. Is it safe to somehow add the load-library preview to my init.el? Or do I risk mucking up something? I'm new to Emacs and primarily trying to learn it because of the AUCTeX preview features, but I don't feel very safe in this environment yet.

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  • What must I learn to parse dynamic HTML sites with PHP?

    - by butteff
    What I must to learn to write php web-site grabber (parser)? It must collect information from other websites, such as as weather forecast, wiki "on this day", some news and other useful and interesting "every day" information! what i must to read for writing m3u player on php? sorry for my bad english

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  • Is it possible to come over the time out issue for a function call in C#?

    - by infant programmer
    In my program I call a method xslTransform.Load(strXmlQueryTransformPath, xslSettings, new XmlUrlResolver()); The problem I am facing is: sometimes this function doesn't execute well within the time. Sometimes compiler raises the time out issue after a long time of trial.. which inturn causes this part of application to shut. That is what I want to avoid. So if it exceeds certain time say 10 seconds I need to recall the method. Is it possible to add some code lines adjacent to this, which can meet the requirement?

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  • What does this PHP (function/construct?) do, and where can I find more documentation on it?

    - by Rob
    Simple question. Here is this code. $r = rand(0,1); $c = ($r==0)? rand(65,90) : rand(97,122); $inputpass .= chr($c); I understand what it does in the end result, but I'd like a better explanation on how it works, so I can use it myself. Sorry if this is a bad question. If you're unsure of what I'm asking about, its the (function?) used here: $c = ($r==0)? rand(65,90) : rand(97,122);

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  • Strange behavior with ajax call complete in JavaScript modules

    - by user2598794
    I have 3 simple modules with JavaScript code and JQuery ajax call. First module lots.js: var Lots = (function ($) { var self = this; var processIsRunning; return { getLots: function (lotsUrl) { var items = []; self.processIsRunning = true; var request = $.ajax({ url: lotsUrl, type: 'POST', success: function (data) { //some code } }); $.when(request).done(function() { //some code self.processIsRunning = false; }); }, isComplete: function () { return !self.processIsRunning; } }; }(jQuery)); Module bids.js: var Bids = (function ($) { return { makeBids: function (bidUrl) { //some code } }; }(jQuery)); Module app.js which bundles all together: var App = (function () { var lots_url = null; var bid_url = null; var self = this; return { if (!self.lots_url) { self.lots_url = lotsUrl; } GetLots: function (lotsUrl) { Lots.getLots(self.lots_url); }, MakeBids: function makeBid(bidUrl) { //some code var isComp = Lots.isComplete(); while (!isComp) { isComp = Lots.isComplete(); } Bids.makeBids(self.bid_url); } }; }()); But in the 'while' loop I always get 'isComplete=false'. In debug I see that 'processIsRunning' in Lots module is always true. What's the problem?

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  • execute javascript function in a another iframe when parent is from different domain.

    - by Frushko
    The page A.com has 2 iframes B.com/page1 and B.com/page2. This is the code of A.com: <html><body> <iframe src="b.com/page1" name="iframe1" id="iframe1"> <iframe src="b.com/page2"> </body></html> I want to execute js function on B.com/page1 from B.com/page2. Both examples below works well when the parent is from the same domain but not in cross domain scenario: parent.window.frames['iframe1'].SomeFunction(args); or parent.document.getElementById('iframe1').contentWindow.SomeFunction(args); Is there any way to do it?

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  • VB.Net Linq Datatable Exists

    - by LarsH
    I would like to use Linq instead of below function : Friend Function IsCollectionInTable2(ByVal apps As DataTable, ByVal collectionId As String) As Boolean For Each row As DataRow In apps.Rows If row("CollectionId").ToString = collectionId Then Return True Next Return False End Function The best I can do is below: Friend Function IsCollectionInTable(ByVal apps As DataTable, ByVal collectionId As String) As Boolean Return (From row In apps.AsEnumerable() Where (row.Field(Of String)("CollectionId") = collectionId) Select row.Field(Of String)("CollectionId")).Count > 0 End Function I would like to use Exists or Any in above function. Performance could be an issue,

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  • Mediawiki authenication replacement showing "Login Required" instead of signing user into wiki

    - by arcdegree
    I'm fairly to MediaWiki and needed a way to automatically log users in after they authenticated to a central server (which creates a session and cookie for applications to use). I wrote a custom authentication extension based off of the LDAP Authentication extension and a few others. The extension simply needs to read some session data to create or update a user and then log them in automatically. All the authentication is handled externally. A user would not be able to even access the wiki website without logging in externally. This extension was placed into production which replaced the old standard MediaWiki authentication system. I also merged user accounts to prepare for the change. By default, a user must be logged in to view, edit, or otherwise do anything in the wiki. My problem is that I found if a user had previously used the built-in MediaWiki authentication system and returned to the wiki, my extension would attempt to auto-login the user, however, they would see a "Login Required" page instead of the page they requested like they were an anonymous user. If the user then refreshed the page, they would be able to navigate, edit, etc. From what I can tell, this issue resolves itself after the UserID cookie is reset or created fresh (but has been known to strangely come up sometimes). To replicate, if there is an older User ID in the "USERID" cookie, the user is shown the "Login Required" page which is a poor user experience. Another way of showing this page is by removing the user account from the database and refreshing the wiki page. As a result, the user will again see the "Login Required" page. Does anyone know how I can use debugging to find out why MediaWiki thinks the user is not signed in when the cookies are set properly and all it takes is a page refresh? Here is my extension (simplified a little for this post): <?php $wgExtensionCredits['parserhook'][] = array ( 'name' => 'MyExtension', 'author' => '', ); if (!class_exists('AuthPlugin')) { require_once ( 'AuthPlugin.php' ); } class MyExtensionPlugin extends AuthPlugin { function userExists($username) { return true; } function authenticate($username, $password) { $id = $_SESSION['id']; if($username = $id) { return true; } else { return false; } } function updateUser(& $user) { $name = $user->getName(); $user->load(); $user->mPassword = ''; $user->mNewpassword = ''; $user->mNewpassTime = null; $user->setRealName($_SESSION['name']); $user->setEmail($_SESSION['email']); $user->mEmailAuthenticated = wfTimestampNow(); $user->saveSettings(); return true; } function modifyUITemplate(& $template) { $template->set('useemail', false); $template->set('remember', false); $template->set('create', false); $template->set('domain', false); $template->set('usedomain', false); } function autoCreate() { return true; } function disallowPrefsEditByUser() { return array ( 'wpRealName' => true, 'wpUserEmail' => true, 'wpNick' => true ); } function allowPasswordChange() { return false; } function setPassword( $user, $password ) { return false; } function strict() { return true; } function initUser( & $user ) { } function updateExternalDB( $user ) { return false; } function canCreateAccounts() { return false; } function addUser( $user, $password ) { return false; } function getCanonicalName( $username ) { return $username; } } function SetupAuthMyExtension() { global $wgHooks; global $wgAuth; $wgHooks['UserLoadFromSession'][] = 'Auth_MyExtension_autologin_hook'; $wgHooks['UserLogoutComplete'][] = 'Auth_MyExtension_UserLogoutComplete'; $wgHooks['PersonalUrls'][] = 'Auth_MyExtension_personalURL_hook'; $wgAuth = new MyExtensionPlugin(); } function Auth_MyExtension_autologin_hook($user, &$return_user ) { global $wgUser; global $wgAuth; global $wgContLang; wfSetupSession(); // Give us a user, see if we're around $tmpuser = new User() ; $rc = $tmpuser->newFromSession(); $rc = $tmpuser->load(); if( $rc && $rc->isLoggedIn() ) { if ( $rc->authenticate($rc->getName(), '') ) { return true; } else { $rc->logout(); } } $id = trim($_SESSION['id']); $name = ucfirst(trim($_SESSION['name'])); if (empty($dsid)) { $result = false; // Deny access return true; } $user = User::newFromName($dsid); if (0 == $user->getID() ) { // we have a new user to add... $user->setName( $id); $user->addToDatabase(); $user->setToken(); $user->saveSettings(); $ssUpdate = new SiteStatsUpdate( 0, 0, 0, 0, 1 ); $ssUpdate->doUpdate(); } else { $user->saveToCache(); } // update email, real name, etc. $wgAuth->updateUser( $user ); $result = true; // Go ahead and log 'em in $user->setToken(); $user->saveSettings(); $user->setupSession(); $user->setCookies(); return true; } function Auth_MyExtension_personalURL_hook(& $personal_urls, & $title) { global $wgUser; unset( $personal_urls['mytalk'] ); unset($personal_urls['Userlogin']); $personal_urls['userpage']['text'] = $wgUser->getRealName(); foreach (array('login', 'anonlogin') as $k) { if (array_key_exists($k, $personal_urls)) { unset($personal_urls[$k]); } } return true; } function Auth_MyExtension_UserLogoutComplete(&$user, &$inject_html, $old_name) { setcookie( $GLOBALS['wgCookiePrefix'] . '_session', '', time() - 3600, $GLOBALS['wgCookiePath']); setcookie( $GLOBALS['wgCookiePrefix'] . 'UserName', '', time() - 3600, $GLOBALS['wgCookiePath']); setcookie( $GLOBALS['wgCookiePrefix'] . 'UserID', '', time() - 3600, $GLOBALS['wgCookiePath']); setcookie( $GLOBALS['wgCookiePrefix'] . 'Token', '', time() - 3600, $GLOBALS['wgCookiePath']); return true; } ?> Here is part of my LocalSettings.php file: ############################# # Disallow Anonymous Access ############################# $wgGroupPermissions['*']['read'] = false; $wgGroupPermissions['*']['edit'] = false; $wgGroupPermissions['*']['createpage'] = false; $wgGroupPermissions['*']['createtalk'] = false; $wgGroupPermissions['*']['createaccount'] = false; $wgShowIPinHeader = false; # For non-logged in users ############################# # Extension: MyExtension ############################# require_once("$IP/extensions/MyExtension.php"); $wgAutoLogin = true; SetupAuthMyExtension(); $wgDisableCookieCheck = true;

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  • Does iPhone SDK Objective C support functions inside of functions?

    - by Moshe
    I know that javascript, for example supports functions inside of functions, like so: function doSomething(){ function doAnothingThing(){ //this function is redefined every time doSomething() is called and only exists inside doSomething() } //you can also stick it inside of conditions if(yes){ function doSomethingElse(){ //this function only exists if yes is true } } } Does objective-c support this? Theoretical example: -(void) doSomething:(id) sender{ -(void) respondToEvent: (id) sender{ //theoretically? ... please? } } BONUS: What is the proper term for a "local" function?

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  • How to return dynamic CSS with ASP.NET MVC?

    - by Morten Mertner
    I need a solution that lets me accomplish the following: Returning CSS that is dynamically generated by an action method Choosing CSS file depending on request parameter or cookie Using a tool to combine and compress (minify) CSS I am currently considering why there is no CssResult in ASP.NET MVC, and whether there might be a reason for its absence. Would creating a custom ActionResult not be the best way to go about this? Is there some other way that I've overlooked to do what I need? Any other suggestions or hints that might be relevant before I embark on this task will also be appreciated :)

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  • Should I be using Expression Blend to design really dynamic UIs?

    - by Robert Rossney
    My company's product is, at its core, a framework for developing metadata-driven UIs. I don't know how to characterize it less succinctly than that, and hope I won't need to for purposes of this question, but we'll see. I've been trying to come up to speed on WPF, and have been building UI prototypes here and there, and recently I decided to see if I could use Expression Blend to help with the design of these UIs. And I'm pretty mystified at this point. It appears to me as though Expresssion Blend is designed with the expectation that you already know all of the objects that are going to be present in the UI at design time. But our program generates these object dynamically at runtime. For instance, a data row might be presented in a horizontal StackPanel containing alternating TextBlocks (for captions) and TextBoxes (for data fields). The number of these objects depends on metadata about the number of columns in the data row. I can, pretty readily, write code that runs through a metadata record and populates a StackPanel dynamically, setting up the binding of all of the controls to properties in either the data or metadata. (A TextBox's Width might be bound to metadata, while its Text is bound to data.) But I can't even begin to figure out how to do something like this in Expression Blend. I can manually create all these controls, so that I have a set of controls that I can apply styles to and work out the visual design of the app, but it's really a pain to do this. I can write code that goes through my data model and emits XAML for all these controls, I suppose, and then copy and paste it. But I'm going to feel really stupid if it turns out there a way to do this sort of thing in Expression Blend and I've dropped back and punted because I'm too dim to figure out the right way to think of it. Is this enough information for someone to try formulating an answer?

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  • is_admin? function in rails? - undefined method Error

    - by Newbie
    Hello! At the moment, I am creating some kind of admin panel/backend for my site. I want to do the following: Only admins (a user has a user_role(integer) -- 1 = admin, 2 = moderator, 3 = user) can see and access a link for the admin panel. So I created an admin_controller. In my admin controller I created a new function called is_admin?: class AdminController < ApplicationController def admin_panel end def is_admin? current_user.user_role == 1 end end my route looks like. map.admin_panel '/admin-panel', :controller => 'admin', :action => 'admin_panel' and in my _sidebar.html.erb (partial in applicaton.html.erb) I created the link: <%= link_to "Admin Panel", :admin_panel unless is_admin? %> Now I get an error called: undefined method `is_admin?' Where is the problem? Please help me solving this problem!

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  • Can the lock function be used to implement thread-safe enumeration?

    - by Daniel
    I'm working on a thread-safe collection that uses Dictionary as a backing store. In C# you can do the following: private IEnumerable<KeyValuePair<K, V>> Enumerate() { if (_synchronize) { lock (_locker) { foreach (var entry in _dict) yield return entry; } } else { foreach (var entry in _dict) yield return entry; } } The only way I've found to do this in F# is using Monitor, e.g.: let enumerate() = if synchronize then seq { System.Threading.Monitor.Enter(locker) try for entry in dict -> entry finally System.Threading.Monitor.Exit(locker) } else seq { for entry in dict -> entry } Can this be done using the lock function? Or, is there a better way to do this in general? I don't think returning a copy of the collection for iteration will work because I need absolute synchronization.

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  • Intercepting mouse events using a global hook. Stop an action from happening.

    - by fMinkel
    I'm attempting to intercept and interrupt mouse events. Lets say I wanted to disable the right mouse button down event, or even the mouse move event. I haven't been able to figure out the interrupting part. I am using the (I assume pretty widely used) following code for Global Hooking of the mouse. Private Structure MSLLHOOKSTRUCT Public pt As Point Public mouseData As Int32 Public flags As Int32 Public time As Int32 Public extra As IntPtr End Structure Private _mouseHook As IntPtr Private Const WH_MOUSE_LL As Int32 = 14 Private Delegate Function MouseHookDelegate(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32 <MarshalAs(UnmanagedType.FunctionPtr)> Private _mouseProc As MouseHookDelegate Private Declare Function SetWindowsHookExW Lib "user32.dll" (ByVal idHook As Int32, ByVal HookProc As MouseHookDelegate, ByVal hInstance As IntPtr, ByVal wParam As Int32) As IntPtr Private Declare Function UnhookWindowsHookEx Lib "user32.dll" (ByVal hook As IntPtr) As Boolean Private Declare Function CallNextHookEx Lib "user32.dll" (ByVal idHook As Int32, ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32 Private Declare Function GetCurrentThreadId Lib "kernel32.dll" () As Integer Private Declare Function GetModuleHandleW Lib "kernel32.dll" (ByVal fakezero As IntPtr) As IntPtr Public Function HookMouse() As Boolean Debug.Print("Mouse Hooked") If _mouseHook = IntPtr.Zero Then _mouseProc = New MouseHookDelegate(AddressOf MouseHookProc) _mouseHook = SetWindowsHookExW(WH_MOUSE_LL, _mouseProc, GetModuleHandleW(IntPtr.Zero), 0) End If Return _mouseHook <> IntPtr.Zero End Function Public Sub UnHookMouse() Debug.Print("Mouse UnHooked") If _mouseHook = IntPtr.Zero Then Return UnhookWindowsHookEx(_mouseHook) _mouseHook = IntPtr.Zero End Sub Private Function MouseHookProc(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32 'Debug.Print("Message = {0}, x={1}, y={2}", wParam.ToInt32, lParam.pt.X, lParam.pt.Y) If wParam.ToInt32 = 513 Then '''interrupt the left mouse button event here, but don't know what to return to do so. End If Return CallNextHookEx(WH_MOUSE_LL, nCode, wParam, lParam) End Function

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  • WHY JSLint complains: "someFunction() was used before it was defined"?

    - by 7hi4g0
    Searching for the JSLint error "was used before it was defined" i've found these: JSLint: Using a function before it's defined error Function was used before it was defined - JSLint JSLint: was used before it was defined jsLint error: “somefunction() was used before it was defined” jslint - Should we tolerate misordered definitions? Problem None of those answers WHY the error is shown. Elaboration According to the ECMA-262 Specification functions are evaluated before execution starts, hence all functions declared using the function keyword are available to all the code idenpendent of the place they were declared (assuming they are acessible on that scope). This is otherwise known as hoisting. Douglas Crockford seems to think it is better to declare every function before the code that uses it regardless of the hoisting effect. According to StackOverflowNewbie in his question, this raises some code organization problems. Not to mention some people, like me, prefer to declare their functions underneath the main/init code. On those questions there are some ways to avoid or fix the error, such as using function expressions vs function declarations. But none of them showed me the reason of the error. Not even Crockford's site. Question(s) Why is it an error to call a function before the declaration, even if it was declared using the function keyword? Is it better to use function expressions instead of function declaration in the JSLint context? If one is preferred, why? Note Not looking for answers like: Crockford is a tyrant Is just Crockford's opinion Thank you :*

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  • What is the function of those film covers on electronic equipment such as mobile screens but also peripheral plastics on a laptop?

    - by leladax
    I understand it may "protect" an area but I don't get why the customer gets it and then takes it off after it was being protected in a full box anyway. Also, should those film covers that surround the plastics around a laptop screen (and not the screen itself) and maybe also on the keyboard be kept on as much as possible? I noticed if one tries to keep them on as much as possible they tend to go off by themselves anyway, but anyway, what's the status quo about it?

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  • How do I dynamically update an instance array to hold a list of dynamic methods on instantiation?

    - by Will
    I am trying to dynamically define methods based on xml mappings. This works really well. However I want to create an instance variable that is a array of the dynamically defined methods. My code looks something like this def xml_attr_reader(*args) xml_list = "" args.each do |arg| string_val = "def #{arg}; " + " xml_mapping.#{arg}; " + "end; " self.class_eval string_val xml_hash = xml_list + "'#{arg}'," end self.class_eval "@xml_attributes = [] if @xml_attributes.nil?;" + "@xml_attributes = @xml_attributes + [#{xml_list}];" + "puts 'xml_attrs = ' + @xml_attributes.to_s;" + "def xml_attributes;" + " puts 'xml_attrs = ' + @xml_attributes.to_s;" + " @xml_attributes;" + "end" end So everything works except when I call xml_attributes on an instance it return null (and prints out 'xml_attrs = '). While the puts before the definition actually prints out the correct array. (when I instantiate the instance)

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  • how to get data from another file?

    - by Ronnie Chester Lynwood
    hey guys i got this jquery codes: jQuery(function ($) { var OSX = { container: null, init: function () { $("input.osx, a.osx").click(function (e) { e.preventDefault(); $("#osx-modal-content").modal({ overlayId: 'osx-overlay', containerId: 'osx-container', closeHTML: null, minHeight: 80, opacity: 65, position: ['0',], overlayClose: true, onOpen: OSX.open, onClose: OSX.close }); }); }, open: function (d) { var self = this; self.container = d.container[0]; d.overlay.fadeIn('slow', function () { $("#osx-modal-content", self.container).show(); var title = $("#osx-modal-title", self.container); title.show(); d.container.slideDown('slow', function () { setTimeout(function () { var h = $("#osx-modal-data", self.container).height() + title.height() + 20; // padding d.container.animate( {height: h}, 200, function () { $("div.close", self.container).show(); $("#osx-modal-data", self.container).show(); } ); }, 300); }); }) }, close: function (d) { var self = this; // this = SimpleModal object d.container.animate( {top:"-" + (d.container.height() + 20)}, 500, function () { self.close(); // or $.modal.close(); } ); } }; OSX.init(); }); this js is gets #osx-modal-content,#osx-modal-title,#osx-modal-data from index.php. how can i get divs from another page? thanks

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  • Is the following combination of components valid to function as a desktop computer? [closed]

    - by Gideon Potgieter
    Could someone with more PC building experience than me tell me whether these PC components can cooperate fully as a self-made PC? Processor: Intel Core i5-3570K Video card: Asus Radeon HD 7870 Motherboard: Gigabyte GA-Z77-D3H RAM: Corsair CMZ16GX3M2A1600C10 Vengeance 16GB 1600MHz CL10 DDR3 (x2) Storage: Western Digital WD1002FAEX (x2) Display: Samsung S24B300HL Sound: Logitech X140 Chassis: Thermaltake V4 Black Edition VM30001W2Z Power supply: Seagate OEM 500W Builder PSU Optical drive: Asus DRW-24B1ST Thanks in advance! (btw, I know 32 GB RAM is unnecessary, but I want to buy it to use as a reserve)

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  • Possible for C++ template to check for a function's existence?

    - by andy
    Is it possible to write a C++ template that changes behavior depending on if a certain member function is defined on a class? Here's a simple example of what I would want to write: template<class T> std::string optionalToString(T* obj) { if (FUNCTION_EXISTS(T->toString)) return obj->toString(); else return "toString not defined"; } So if class T has "toString" defined then it uses it, otherwise it doesn't. The magical part that I don't know how to do is the "FUNCTION_EXISTS" part.

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  • How can I specify a dynamic height for an ImageView?

    - by kefs
    I have an ImageView at the top of my display that looks like the following: +----------------------------------------------+ ¦ ImageView +--------------+ ¦ ¦ ¦ ¦ ¦ ¦ ¦ Actual image ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ ¦ +--------------+ ¦ +----------------------------------------------+ Below this, I have a series of Buttons and TextViews.. I would like the ImageView's height to dynamically increase depending on the max height of the screen. I'm aligning the layout containing the buttons along the bottom of edge of the screen, and I would like the rest of the screen taken up by the above ImageView. Also, since the ImageView contains a centered image, I would also like to set min height, and a scrollbar if the screen is too small to display the imageview and the buttons below. Thanks! Is this possible?

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  • C++ is there a difference between assignment inside a pass by value and pass by reference function?

    - by Rémy DAVID
    Is there a difference between foo and bar: class A { Object __o; void foo(Object& o) { __o = o; } void bar(Object o) { __o = o; } } As I understand it, foo performs no copy operation on object o when it is called, and one copy operation for assignment. Bar performs one copy operation on object o when it is called and another one for assignment. So I can more or less say that foo uses 2 times less memory than bar (if o is big enough). Is that correct ? Is it possible that the compiler optimises the bar function to perform only one copy operation on o ? i.e. makes __o pointing on the local copy of argument o instead of creating a new copy?

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