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  • Does everything after my try statement have to be encompassed in that try statement to access variab

    - by Mithrax
    I'm learning java and one thing I've found that I don't like, is generally when I have code like this: import java.util.*; import java.io.*; public class GraphProblem { public static void main(String[] args) { if (args.length < 2) { System.out.println("Error: Please specify a graph file!"); return; } FileReader in = new FileReader(args[1]); Scanner input = new Scanner(in); int size = input.nextInt(); WeightedGraph graph = new WeightedGraph(size); for(int i = 0; i < size; i++) { graph.setLabel(i,Character.toString((char)('A' + i))); } for(int i = 0; i < size; i++) { for(int j = 0; j < size; j++) { graph.addEdge(i, j, input.nextInt()); } } // .. lots more code } } I have an uncaught exception around my FileReader. So, I have to wrap it in a try-catch to catch that specific exception. My question is does that try { } have to encompass everything after that in my method that wants to use either my FileReader (in) or my Scanner (input)? If I don't wrap the whole remainder of the program in that try statement, then anything outside of it can't access the in/input because it may of not been initialized or has been initialized outside of its scope. So I can't isolate the try-catch to just say the portion that intializes the FileReader and close the try statement immediately after that. So, is it the "best practice" to have the try statement wrapping all portions of the code that are going to access variables initialized in it? Thanks!

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  • Extremely CPU Intensive Alarm Clock

    - by SoulBeaver
    For some reason my program, a console alarm clock I made for laughs and practice, is extremely CPU intensive. It consumes about 2mB RAM, which is already quite a bit for such a small program, but it devastates my CPU with over 50% resources at times. Most of the time my program is doing nothing except counting down the seconds, so I guess this part of my program is the one that's causing so much strain on my CPU, though I don't know why. If it is so, could you please recommend a way of making it less, or perhaps a library to use instead if the problem can't be easily solved? /* The wait function waits exactly one second before returning to the * * called function. */ void wait( const int &seconds ) { clock_t endwait; // Type needed to compare with clock() endwait = clock() + ( seconds * CLOCKS_PER_SEC ); while( clock() < endwait ) {} // Nothing need be done here. } In case anybody browses CPlusPlus.com, this is a genuine copy/paste of the clock() function they have written as an example for clock(). Much why the comment //Nothing need be done here is so lackluster. I'm not entirely sure what exactly clock() does yet. The rest of the program calls two other functions that only activate every sixty seconds, otherwise returning to the caller and counting down another second, so I don't think that's too CPU intensive- though I wouldn't know, this is my first attempt at optimizing code. The first function is a console clear using system("cls") which, I know, is really, really slow and not a good idea. I will be changing that post-haste, but, since it only activates every 60 seconds and there is a noticeable lag-spike, I know this isn't the problem most of the time. The second function re-writes the content of the screen with the updated remaining time also only every sixty seconds. I will edit in the function that calls wait, clearScreen and display if it's clear that this function is not the problem. I already tried to reference most variables so they are not copied, as well as avoid endl as I heard that it's a little slow compared to \n.

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  • Can we have a component-scoped bean in a JSF2 composite component?

    - by Pradyumna
    Hi, I was wondering how I could create "component-scoped" beans, or so-to-say, "local variables inside a composite component" that are private to the instance of the composite component, and live as long as that instance lives. Below are more details, explained with an example: Suppose there is a "calculator" component - something that allows users to type in a mathematical expression, and evaluates its value. Optionally, it also plots the associated function. I can make a composite component that has: a text box for accepting the math expression two buttons called "Evaluate", and "Plot" another nested component that plots the function It is evidently a self-contained piece of function; so that somebody who wants to use it may just say <math:expressionEvaluator /> But obviously, the implementation would need a java object - something that evaluates the expression, something that computes the plot points, etc. - and I imagine it can be a bean - scoped just for this instance of this component, not a view-scoped or request-scoped bean that is shared across all instances of the component. How do I create such a bean? Is that even possible with composite components?

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  • C++: Reference and Pointer question (example regarding OpenGL)

    - by Jay
    I would like to load textures, and then have them be used by multiple objects. Would this work? class Sprite { GLuint* mTextures; // do I need this to also be a reference? Sprite( GLuint* textures ) // do I need this to also be a reference? { mTextures = textures; } void Draw( textureNumber ) { glBindTexture( GL_TEXTURE_2D, mTextures[ textureNumber ] ); // drawing code } }; // normally these variables would be inputed, but I did this for simplicity. const int NUMBER_OF_TEXTURES = 40; const int WHICH_TEXTURE = 10; void main() { std::vector<GLuint> the_textures; the_textures.resize( NUMBER_OF_TEXTURES ); glGenTextures( NUMBER_OF_TEXTURES, &the_textures[0] ); // texture loading code Sprite the_sprite( &the_textures[0] ); the_sprite.Draw( WHICH_TEXTURE ); } And is there a different way I should do this, even if it would work? Thanks.

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  • Run arbitrary subprocesses on Windows and still terminate cleanly?

    - by Weeble
    I have an application A that I would like to be able to invoke arbitrary other processes as specified by a user in a configuration file. Batch script B is one such process a user would like to be invoked by A. B sets up some environment variables, shows some messages and invokes a compiler C to do some work. Does Windows provide a standard way for arbitrary processes to be terminated cleanly? Suppose A is run in a console and receives a CTRL+C. Can it pass this on to B and C? Suppose A runs in a window and the user tries to close the window, can it cancel B and C? TerminateProcess is an option, but not a very good one. If A uses TerminateProcess on B, C keeps running. This could cause nasty problems if C is long-running, since we might start another instance of C to operate on the same files while the first instance of C is still secretly at work. In addition, TerminateProcess doesn't result in a clean exit. GenerateConsoleCtrlEvent sounds nice, and might work when everything's running in a console, but the documentation says that you can only send CTRL+C to your own console, and so wouldn't help if A were running in a window. Is there any equivalent to SIGINT on Windows? I would love to find an article like this one: http://www.cons.org/cracauer/sigint.html for Windows.

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  • Self referencing userdata and garbage collection

    - by drtwox
    Because my userdata objects reference themselves, I need to delete and nil a variable for the garbage collector to work. Lua code: obj = object:new() -- -- Some time later obj:delete() -- Removes the self reference obj = nil -- Ready for collection C Code: typedef struct { int self; // Reference to the object // Other members and function references removed } Object; // Called from Lua to create a new object static int object_new( lua_State *L ) { Object *obj = lua_newuserdata( L, sizeof( Object ) ); // Create the 'self' reference, userdata is on the stack top obj->self = luaL_ref( L, LUA_REGISTRYINDEX ); // Put the userdata back on the stack before returning lua_rawgeti( L, LUA_REGISTRYINDEX, obj->self ); // The object pointer is also stored outside of Lua for processing in C return 1; } // Called by Lua to delete an object static int object_delete( lua_State *L ) { Object *obj = lua_touserdata( L, 1 ); // Remove the objects self reference luaL_unref( L, LUA_REGISTRYINDEX, obj->self ); return 0; } Is there some way I can set the object to nil in Lua, and have the delete() method called automatically? Alternatively, can the delete method nil all variables that reference the object? Can the self reference be made 'weak'?

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  • Extracting exported functions out of a shared lib (ubuntu)

    - by Pingu
    the title already describes my problem. I found this post, but it didn't completely answers my question. With the help of it i got this output from nm... $nm -C -g -D ./libLoggingHandler.so 000000cc A _DYNAMIC ... 000042e0 T write_str(char*, char const*, int*) 00005a78 T RingBuffer::WriteUnlock() ... 00005918 T TraceLines::GetItemSize() ... U SharedMemory::attach(int, void const*, int) ... 00003810 T TraceProfile::FindLineNr(int, int) ... 00002d40 T LoggingHandler::getLogLevel() ... U SharedResource::getSharedResourceKey(char const*, int) ... which are the exported functions? I already found a hint in this post, that the "T" indicates that its getting exported. But if i check the nm manual here, it just says T - The symbol is in the text (code) section. My questions is: Does this output give me the information which functions are exported functions (or variables)? If not, how do i get it? Greetings, Pingu

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  • How to encapsulate a WinAPI application into a C++ class

    - by Semen Semenych
    There is a simple WinAPI application. All it does currently is this: register a window class register a tray icon with a menu create a value in the registry in order to autostart and finally, it checks if it's unique using a mutex As I'm used to writing code mainly in C++, and no MFC is allowed, I'm forced to encapsulate this into C++ classes somehow. So far I've come up with such a design: there is a class that represents the application it keeps all the wndclass, hinstance, etc variables, where the hinstance is passed as a constructor parameter as well as the icmdshow and others (see WinMain prototype) it has functions for registering the window class, tray icon, reigstry information it encapsulates the message loop in a function In WinMain, the following is done: Application app(hInstance, szCmdLIne, iCmdShow); return app.exec(); and the constructor does the following: registerClass(); registerTray(); registerAutostart(); So far so good. Now the question is : how do I create the window procedure (must be static, as it's a c-style pointer to a function) AND keep track of what the application object is, that is, keep a pointer to an Application around. The main question is : is this how it's usually done? Am I complicating things too much? Is it fine to pass hInstance as a parameter to the Application constructor? And where's the WndProc? Maybe WndProc should be outside of class and the Application pointer be global? Then WndProc invokes Application methods in response to various events.

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  • Form validation

    - by kielie
    Hi guys, I need to create a form that has many of the same fields, that have to be inserted into a database, but the problem I have is that if a user only fills in one or two of the rows, the form will still submit the blank data of the empty fields along with the one or two fields the user has filled in. How can I check for the rows that have not been filled in and leave them out of the query? or check for those that have been filled in and add them to the query. . . The thank_you.php file will capture the $_POST variables and add them to the database. <form method="post" action="thank_you.php"> Name: <input type="text" size="28" name="name1" /> E-mail: <input type="text" size="28" name="email1" /> <br /> Name: <input type="text" size="28" name="name2" /> E-mail: <input type="text" size="28" name="email2" /> <br /> Name: <input type="text" size="28" name="name3" /> E-mail: <input type="text" size="28" name="email3" /> <br /> Name: <input type="text" size="28" name="name4" /> E-mail: <input type="text" size="28" name="email4" /> <input type="image" src="images/btn_s.jpg" /> </form> I am assuming that I could use javascript or jQuery to accomplish this, how would I go about doing this? Thanx in advance for the help.

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  • Why does this Haskell code produce the "infinite type" error?

    - by Charlie Flowers
    I am new to Haskell and facing a "cannot construct infinite type" error that I cannot make sense of. In fact, beyond that, I have not been able to find a good explanation of what this error even means, so if you could go beyond my basic question and explain the "infinite type" error, I'd really appreciate it. Here's the code: intersperse :: a -> [[a]] -> [a] -- intersperse '*' ["foo","bar","baz","quux"] -- should produce the following: -- "foo*bar*baz*quux" -- intersperse -99 [ [1,2,3],[4,5,6],[7,8,9]] -- should produce the following: -- [1,2,3,-99,4,5,6,-99,7,8,9] intersperse _ [] = [] intersperse _ [x] = x intersperse s (x:y:xs) = x:s:y:intersperse s xs And here's the error trying to load it into the interpreter: Prelude :load ./chapter.3.ending.real.world.haskell.exercises.hs [1 of 1] Compiling Main ( chapter.3.ending.real.world.haskell.exercises.hs, interpreted ) chapter.3.ending.real.world.haskell.exercises.hs:147:0: Occurs check: cannot construct the infinite type: a = [a] When generalising the type(s) for `intersperse' Failed, modules loaded: none. Thanks. EDIT: Thanks to the responses, I have corrected the code and I also have a general guideline for dealing with the "infinite type" error in Haskell: Corrected code intersperse _ [] = [] intersperse _ [x] = x intersperse s (x:xs) = x ++ s:intersperse s xs What the problem was: My type signature states that the second parameter to intersperse is a list of lists. Therefore, when I pattern matched against "s (x:y:xs)", x and y became lists. And yet I was treating x and y as elements, not lists. Guideline for dealing with the "infinite type" error: Most of the time, when you get this error, you have forgotten the types of the various variables you're dealing with, and you have attempted to use a variable as if it were some other type than what it is. Look carefully at what type everything is versus how you're using it, and this will usually uncover the problem.

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  • What is the right path for PHP includes on a Mac?

    - by skorned
    Running Mac OS X 10.5.8, with PHP 5.2.11 Pre-installed. Using Coda 1.6.10. I'm writing PHP files, and then preview them running from file, not server. This was working fine till I tried PHP includes. These don't work as a relative path, only as an absolute from the root of the drive. Is there any way I can use statements like include_once "common/header.php"; without specifying my entire file path like so : include_once "/Volumes/Macintosh HD/Users/neil/Desktop/Website/ColoredLists_v1.0/common/base.php"; ,where ColoredLists_v1.0 is the directory with all the website files in it. I tried solutions like prepending _SERVER[DOCUMENT_ROOT] or dirname(File) to the file paths, but that didn't work as the variables were not set. Is there any easy way to do this, or a configuration I can change so that it looks in a specific directory by default instead of looking at the drive root? Currently, echo_include_path shows .: When I include this line at the start of the script, it works: set_include_path('/Volumes/Macintosh HD/Users/neil/Desktop/Website/ColoredLists_v1.0'); However, if I want to do this for all my scripts, I can't seem to make the change permanent. Even after I edited the Unix include_path in my php.ini, it doesn't seem to work.

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  • authorise user from mysql database

    - by Jacksta
    I suck at php, and cant find the error here. The script gets 2 variables "username" and "password" from a html from then check them against a MySQL databse. When I run this I get the follow error "Query was empty" <? if ((!$_POST[username]) || (!$_POST[password])) { header("Location: show_login.html"); exit; } $db_name = "testDB"; $table_name = "auth_users"; $connection = @mysql_connect("localhost", "admin", "pass") or die(mysql_error()); $db = @mysql_select_db($db_name, $connection) or die(mysql_error()); $slq = "SELECT * FROM $table_name WHERE username ='$_POST[username]' AND password = password('$_POST[password]')"; $result = @mysql_query($sql, $connection) or die(mysql_error()); $num = mysql_num_rows($result); if ($num != 0) { $msg = "<p>Congratulations, you're authorised!</p>"; } else { header("Location: show_login.html"); exit; } ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Secret Area</title> </head> <body> <? echo "$msg"; ?> </body> </html>

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  • Recursive powerof-function, see if you can solve it

    - by Jonas B
    First of all, this is not schoolwork - just my curiousity as I for some reason can't get my head around it and solve it. I come up with these stupid things all the time and it annoys the hell out of me when I cant solve them. Code example is in C# but solution doesn't have to be in any particular programming-language. long powerofnum(short num, long powerof) { return powerofnum2(num, powerof, powerof); } long powerofnum2(short num, long powerof, long holder) { if (num == 1) return powerof; else { return powerof = powerofnum2(num - 1, holder * powerof, holder); } } As you can see I have two methods. I call for powerofnum(value, powerofvalue) which then calls the next method with the powerofvalue also in a third parameter as a placeholder so it remembers the original powerof value through the recursion. What I want to accomplish is to do this with only one method. I know I could just declare a variable in the first method with the powerof value to remember it and then iterate from 0 to value of num. But as this is a theoretical question I want it done recursively. I could also in the first method just take a third parameter called whatever to store the value just like I do in the second method that is called by the first, but that looks really stupid. Why should you have to write what seems like the same parameter twice? Rules explained in short: no iteration scope-specific variables only only one method Anyhow, I'd appreciate a clean solution. Good luck :)

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  • Identical files from different servers. Why might IE 8 display them differently?

    - by jasongetsdown
    I'm working on a site that will go on my company's intranet. I developed it locally on my computer, checking it in different browsers and on colleague's computers, and when it was done I handed it off to IT. They put identical copies on a staging server, and on the production server. This is a site built only with html, javascript, and css. No server side scripting. It also uses a DWF viewer plugin from Autodesk. It is a single standalone page (not part of a CMS) that allows users to load drawings into the viewer and then click to see info from a database of space info saved in a series of js arrays (the space DB software spits out a js file with all the info listed in array literals, creating a crap ton of global variables - ugh, but I digress). When I followed their links (using IE 8) the version on the staging server looked as expected, but the layout is hosed on the version from the production server. Specifically, it seems like a div that is supposed to flow to the right of a div that is float: left is displaying below the floated div at full width, as though it was clear: left (which it is not). It also has the wrong height. I downloaded the files from each and they are identical to my local version. Frustrated, I cleared my browser's cache, restarted my computer, checked it on a colleague's computer who also has IE 8. All the same issue. Staging server good. Production server bad. Finally I uninstalled IE 8 and looked at it in IE 6. Both versions looked fine. So, to recap. Two different servers. No server side scripting. Identical files. One browser agrees they are identical, the other does not. What could cause this?

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  • Wrapper class that creates objects at runtime and stores data in an array.

    - by scriptingalias
    I tried making a wrapper class that encapsulates an object, a string (for naming and differentiating the object instance), and an array to store data. The problem I'm having now is accessing this class using methods that determine the "name" of the object and also reading the array containing some random variables. import java.util.Arrays; import java.util.Random; public class WrapperClass { String varName; Object varData; int[] array = new int[10]; public WrapperClass(String name, Object data, int[] ARRAY) { varName = name; varData = data; array = ARRAY; } public static void getvalues() { } public static void main(String[] args) { int[] array = new int[10]; Random random = new Random(3134234); for(int i = 0; i < 10; i++) { for (int c = 0; c < 10; c++) { array[c] = random.nextInt();//randomly creates data } WrapperClass w = new WrapperClass("c" + i, new Object(),array); } } }

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  • `this` in global scope in ECMAScript 6

    - by Nathan Wall
    I've tried looking in the ES6 draft myself, but I'm not sure where to look: Can someone tell me if this in ES6 necessarily refers to the global object? Will this object have same members as the global scope? If you could answer for ES5 that would be helpful as well. I know this in global scope refers to the global object in the browser and in most other ES environments, like Node. I just want to know if that's the defined behavior by the spec or if that's extended behavior that implementers have added (and if this behavior will continue in ES6 implementations). In addition, is the global object always the same thing as the global scope? Or are there distinctions? Update - Why I want to know: I am basically trying to figure out how to get the global object reliably in ES5 & 6. I can't rely on window because that's specific to the browser, nor can I rely on global because that's specific to environments like Node. I know this in Node can refer to module in module scope, but I think it still refers to global in global scope. I want a cross-environment ES5 & 6 compliant way to get the global object (if possible). It seems like in all the environments I know of this in global scope does that, but I want to know if it's part of the actual spec (and so reliable across any environment that I may not be familiar with). I also need to know if the global scope and the global object are the same thing by the spec. In other words will all variables in global scope be the same as globalobject.variable_name?

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  • How to read the birthday_date from the Facebook API

    - by Steve
    I have been chasing my tail on this! And it should be so simple!! I have an app in FaceBook that is working fine. However, I need to get the user's birth date. I have successfully got the request for extended permissions, but cannot get the birthday_date out and into a variable/store in database. <?php require_once('facebook.php'); $facebook = new Facebook(array( 'appId' => 'xxxxx', 'secret' => 'yyyyyyy', 'cookie' => true )); if ($facebook->getSession()) { $uid = $facebook->getUser(); $fbme = $facebook->api('/me'); } else { $params = array( 'fbconnect'=>0, 'canvas'=>1, 'req_perms'=>'publish_stream','email','user_location','user_birthday' ); $loginUrl = $facebook->getLoginUrl($params); print "<script type='text/javascript'>top.location.href = '$loginUrl';</script>"; } $session = $facebook->getSession(); $token = $session['access_token']; I would be very grateful if someone could show me the PHP code that reads the extended permissions and places the results into variables. Thanks Steve

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  • NullPointerException on Activity Testing Tutorial

    - by Bendik
    Hello, I am currently trying the activity testing tutorial (Found here), and have a problem. It seems that whenever I try to call something inside the UIThread, I get a java.lang.NullPointerException. public void testSpinnerUI() { mActivity.runOnUiThread( new Runnable() { public void run() { mSpinner.requestFocus(); } }); } This gives me: Incomplete: java.lang.NullPointerException and nothing else. I have tried this on two different samples now, with the same result. I tried with a try/catch clause around the mSpinner.requestFocus() call, and it seems that mSpinner is null inside the thread. I have set it properly up with the setUp() function found in the same sample, and a quick assertNotNull( mSpinner ) shows me that mSpinner is in fact not null after the setUp() function. What can be the cause of this? EDIT; ok, some more testing has been done. It seems that the application that is being tested resets between each test. This essentially makes me have to reinstantiate all variables between each test. Is this normal?

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  • Creating an object in the loop

    - by Jacob
    std::vector<double> C(4); for(int i = 0; i < 1000;++i) for(int j = 0; j < 2000; ++j) { C[0] = 1.0; C[1] = 1.0; C[2] = 1.0; C[3] = 1.0; } is much faster than for(int i = 0; i < 1000;++i) for(int j = 0; j < 2000; ++j) { std::vector<double> C(4); C[0] = 1.0; C[1] = 1.0; C[2] = 1.0; C[3] = 1.0; } I realize this happens because std::vector is repeatedly being created and instantiated in the loop, but I was under the impression this would be optimized away. Is it completely wrong to keep variables local in a loop whenever possible? I was under the (perhaps false) impression that this would provide optimization opportunities for the compiler. EDIT: I use VC++2005 (release mode) with full optimization (/Ox)

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  • $_SESSION v. $_COOKIE

    - by taeja87
    I learned about $_SESSION about several weeks ago when creating a login page. I can successfully login and use it with variables. Currently I am trying to understand $_SESSION and $_COOKIE. Please correct me if I am wrong, I can use $_SESSION when logging in and moving around pages. With $_COOKIE, it is used to remember when I last visit and preferences. Another thing involving cookies is that when websites use advertisements (for example: Google AdSense), they use the cookies to track when visitor click on a advertisement, right? I can use both ($_SESSION & $_COOKIE)? I read somewhere that you can store the session_id as value for the cookie. Also, I read about security which let to me finding this: What do I need to store in the php session when user logged in?. Is using session_regenerate_id good for when a user comes back to the site? And this: How to store a cookie with php involving uniqid. For those wanting to know about the login, I use email and password. That way the user can be able to change their username. I look forward to learning more about these two from anybody who would like to share their knowledge about it. If I asked too many question, you can just answer the one that you have more experience with. If you need more information, just ask since I might have forgotten to include something. Thank You. Found this: What risks should I be aware of before allowing advertisements being placed on my website?

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  • How to achieve interaction between GUI class with logic class

    - by volting
    Im new to GUI programming, and haven't done much OOP. Im working on a basic calculator app to help me learn GUI design and to brush up on OOP. I understand that anything GUI related should be kept seperate from the logic, but Im unsure how to implement interaction between logic an GUI classes when needed i.e. basically passing variables back and forth... Im using TKinter and when I pass a tkinter variable to my logic it only seems to hold the string PY_VAR0. def on_equal_btn_click(self): self.entryVariable.set(self.entryVariable.get() + "=") calculator = Calc(self.entryVariable) self.entryVariable.set(calculator.calculate()) Im sure that im probably doing something fundamentally wrong and probabaly really stupid, I spent a considerable amount of time experimenting (and searching for answers online) but Im getting no where. Any help would be appreciated. Thanks, V The Full Program (well just enough to show the structure..) import Tkinter class Gui(Tkinter.Tk): def __init__(self,parent): Tkinter.Tk.__init__(self,parent) self.parent = parent self.initialize() def initialize(self): self.grid() self.create_widgets() """ grid config """ #self.grid_columnconfigure(0,weight=1,pad=0) self.resizable(False, False) def create_widgets(self): """row 0 of grid""" """Create Text Entry Box""" self.entryVariable = Tkinter.StringVar() self.entry = Tkinter.Entry(self,width=30,textvariable=self.entryVariable) self.entry.grid(column=0,row=0, columnspan = 3 ) self.entry.bind("<Return>", self.on_press_enter) """create equal button""" equal_btn = Tkinter.Button(self,text="=",width=4,command=self.on_equal_btn_click) equal_btn.grid(column=3, row=0) """row 1 of grid""" """create number 1 button""" number1_btn = Tkinter.Button(self,text="1",width=8,command=self.on_number1_btn_click) number1_btn.grid(column=0, row=1) . . . def on_equal_btn_click(self): self.entryVariable.set(self.entryVariable.get() + "=") calculator = Calc(self.entryVariable) self.entryVariable.set(calculator.calculate()) class Calc(): def __init__(self, equation): self.equation = equation def calculate(self): #TODO: parse string and calculate... return self.equation if __name__ == "__main__": app = Gui(None) app.title('Calculator') app.mainloop()

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  • KO3: How to deal with stylesheets and scriptfiles

    - by Svish
    I'm using Kohana 3 and it's template controller. My main site template controller currently looks something like this: <?php defined('SYSPATH') or die('No direct script access.'); abstract class Controller_SiteTemplate extends Controller_Template { public function before() { parent::before(); // Initialize default template variables $this->template->styles = Kohana::config('site.styles'); $this->template->scripts = Kohana::config('site.scripts'); $this->template->title = ''; $this->template->content = ''; } } And then in my template view I do: <?php # Styles foreach($styles as $file => $media) echo HTML::style($file, array('media' => $media)).PHP_EOL ?> <?php # Scripts foreach($scripts as $file) echo HTML::script($file).PHP_EOL ?> This works alright. The problem is that it requires the style- and script files to be added in the controller, which shouldn't really have to care about those. It also makes it a hassle if the views are done by someone else than me since they would have to fool around with the controller just to add a new stylesheet or a new script file. How can this be done in a better way? Just to clearify, what I am wondering is how to deal with page specific stylesheets and scripts. The default and site-wide ones I have no problem with fetching from a config file or just put directly in the template view. My issue is how to add custom ones for specific pages in a good way.

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  • Haskell Cons Operator (:)

    - by Carson Myers
    I am really new to Haskell (Actually I saw "Real World Haskell" from O'Reilly and thought "hmm, I think I'll learn functional programming" yesterday) and I am wondering: I can use the construct operator to add an item to the beginning of a list: 1 : [2,3] [1,2,3] I tried making an example data type I found in the book and then playing with it: --in a file data BillingInfo = CreditCard Int String String | CashOnDelivery | Invoice Int deriving (Show) --in ghci $ let order_list = [Invoice 2345] $ order_list [Invoice 2345] $ let order_list = CashOnDelivery : order_list $ order_list [CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, ...- etc... it just repeats forever, is this because it uses lazy evaluation? -- EDIT -- okay, so it is being pounded into my head that let order_list = CashOnDelivery:order_list doesn't add CashOnDelivery to the original order_list and then set the result to order_list, but instead is recursive and creates an infinite list, forever adding CashOnDelivery to the beginning of itself. Of course now I remember that Haskell is a functional language and I can't change the value of the original order_list, so what should I do for a simple "tack this on to the end (or beginning, whatever) of this list?" Make a function which takes a list and BillingInfo as arguments, and then return a list? -- EDIT 2 -- well, based on all the answers I'm getting and the lack of being able to pass an object by reference and mutate variables (such as I'm used to)... I think that I have just asked this question prematurely and that I really need to delve further into the functional paradigm before I can expect to really understand the answers to my questions... I guess what i was looking for was how to write a function or something, taking a list and an item, and returning a list under the same name so the function could be called more than once, without changing the name every time (as if it was actually a program which would add actual orders to an order list, and the user wouldn't have to think of a new name for the list each time, but rather append an item to the same list).

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  • Java: Comparing a class with another within that class using a my own .equals

    - by user1670252
    I am making a method .equals replacing the equals method used. It accepts a object. I want it to check if that object equals the class that runs the .equals class. I know I want to compare all the private methods I have to that object. Is there a way to do this without making another private class to get the private variables from the object? How do I do this to compare equality not identity? I am stuck on this. Do i have to use == to compare? Also looking online i see others use recursion. If this is the way i have to do it can you show and explain it to me? so an example i have public boolean equals(Object o) { this is in a class we will call bobtheBuilder (first thing to pop in my head) I want to check if the object o is equal to the class he has private object array and a private int. I assume I want to check if the array and int of this class equal the array and int of the object.

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  • How to make command-line options mandatory with GLib?

    - by ahe
    I use GLib to parse some command-line options. The problem is that I want to make two of those options mandatory so that the program terminates with the help screen if the user omits them. My code looks like this: static gint line = -1; static gint column = -1; static GOptionEntry options[] = { {"line", 'l', 0, G_OPTION_ARG_INT, &line, "The line", "L"}, {"column", 'c', 0, G_OPTION_ARG_INT, &column, "The column", "C"}, {NULL} }; ... int main(int argc, char** argv) { GError *error = NULL; GOptionContext *context; context = g_option_context_new ("- test"); g_option_context_add_main_entries (context, options, NULL); if (!g_option_context_parse(context, &argc, &argv, &error)) { usage(error->message, context); } ... return 0; } If I omit one of those parameters or both on the command-line g_option_context_parse() still succeeds and the values in question (line and or column) are still -1. How can I tell GLib to fail parsing if the user doesn't pass both options on the command-line? Maybe I'm just blind but I couldn't find a flag I can put into my GOptionEntry data structure to tell it to make those fields mandatory. Of course I could check if one of those variables is still -1 but then the user could just have passed this value on the command-line and I want to print a separate error message if the values are out of range.

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