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  • Android: Unable to access a local website over HTTPS

    - by user1253789
    I am trying to access a locally hosted website and get its HTML source to parse. I have few questions: 1) Can I use "https://An IP ADDRESS HERE" as a valid URL to try and access. I do not want to make changes in the /etc/hosts file so I want to do it this way. 2) I cannot get the html, since it is giving me Handshake exceptions and Certificate issues. I have tried a lot of help available over the web , but am not successful. Here is the code I am using: public class MainActivity extends Activity { private TextView textView; String response = ""; String finalresponse=""; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView = (TextView) findViewById(R.id.TextView01); System.setProperty("javax.net.ssl.trustStore","C:\\User\\*" ); System.setProperty("javax.net.ssl.trustStorePassword", "" ); } private class DownloadWebPageTask extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... urls) { TrustManager[] trustAllCerts = new TrustManager[] { new X509TrustManager() { public java.security.cert.X509Certificate[] getAcceptedIssuers() { return null; } public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType) { } public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType) { } } }; try { SSLContext sc = SSLContext.getInstance("SSL"); sc.init(null, trustAllCerts, new java.security.SecureRandom()); HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory()); } catch (Exception e) { } try { URL url = new URL("https://172.27.224.133"); HttpsURLConnection con =(HttpsURLConnection)url.openConnection(); con.setHostnameVerifier(new AllowAllHostnameVerifier()); finalresponse=readStream(con.getInputStream()); } catch (Exception e) { e.printStackTrace(); } return finalresponse; } private String readStream(InputStream in) { BufferedReader reader = null; try { reader = new BufferedReader(new InputStreamReader(in)); String line = ""; while ((line = reader.readLine()) != null) { response+=line; } } catch (IOException e) { e.printStackTrace(); } finally { if (reader != null) { try { reader.close(); } catch (IOException e) { e.printStackTrace(); } } } return response; } @Override protected void onPostExecute(String result) { textView.setText(finalresponse); } } public void readWebpage(View view) { DownloadWebPageTask task = new DownloadWebPageTask(); task.execute(new String[] { "https://172.27.224.133" }); } }

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  • Please Describe Your Struggles with Minimizing Use of Global Variables

    - by MetaHyperBolic
    Most of the programs I write are relatively flowchartable processes, with a defined start and hoped-for end. The problems themselves can be complex but do not readily lean towards central use of objects and event-driven programming. Often, I am simply churning through great varied batches of text data to produce different text data. Only occasionally do I need to create a class: As an example, to track warnings, errors, and debugging message, I created a class (Problems) with one instantiation (myErr), which I believe to be an example of the Singleton design pattern. As a further factor, my colleagues are more old school (procedural) than I and are unacquainted with object-oriented programming, so I am loath to create things they could not puzzle through. And yet I hear, again and again, how even the Singleton design pattern is really an anti-pattern and ought to be avoided because Global Variables Are Bad. Minor functions need few arguments passed to them and have no need to know of configuration (unchanging) or program state (changing) -- I agree. However, the functions in the middle of the chain, which primarily control program flow, have a need for a large number of configuration variables and some program state variables. I believe passing a dozen or more arguments along to a function is a "solution," but hardly an attractive one. I could, of course, cram variables into a single hash/dict/associative array, but that seems like cheating. For instance, connecting to the Active Directory to make a new account, I need such configuration variables as an administrative username, password, a target OU, some default groups, a domain, etc. I would have to pass those arguments down through a variety of functions which would not even use them, merely shuffle them off down through a chain which would eventually lead to the function that actually needs them. I would at least declare the configuration variables to be constant, to protect them, but my language of choice these days (Python) provides no simple manner to do this, though recipes do exist as workarounds. Numerous Stack Overflow questions have hit on the why? of the badness and the requisite shunning, but do not often mention tips on living with this quasi-religious restriction. How have you resolved, or at least made peace with, the issue of global variables and program state? Where have you made compromises? What have your tricks been, aside from shoving around flocks of arguments to functions?

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  • iOS dynamic object creation

    - by Abdul Ahmad
    I've worked with Xcode and iOS on a few personal projects and have always used non-object-oriented designs for everything... just because I've been doing mostly learning/experimenting with things. Now I've been trying to implement some object oriented design into one game I've made previously. The idea is, I have a space ship that can shoot bullets. In the past I basically added the UIImageView to the storyboard and then connected it to the .h file and from there did things on it like move it around or whatever (using CGPointMake). The idea now is to make a method (and a whole other class soon) that will create a UIImageView programmatically, allocate it, add it to the superview etc... I've got this working so far, easy stuff, but the next part is a bit harder. Where do I store this local variable "bullet"? I've been saving it to an NSMutableArray and doing the following: (actually here are the methods that I have) -(void)movement { for (int i = 0; i < [array1 count]; i ++) { UIImageView *a = [array1 objectAtIndex:i]; a.center = CGPointMake(a.center.x + 2, a.center.y); if (a.center.x > 500) { [array1 removeObjectAtIndex:i]; [a removeFromSuperview]; } } } -(void)getBullet { UIImageView *bullet = [[UIImageView alloc] initWithFrame:CGRectMake(ship.center.x + 20, ship.center.y - 2, 15, 3)]; bullet.image = [UIImage imageNamed:@"bullet2.png"]; bullet.hidden = NO; [self.view addSubview:bullet]; [array1 addObject:bullet]; } (by the way, array1 is declared in the .h file) and theres a timer that controls the movement method timer = [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(movement) userInfo:nil repeats:YES]; first question is: what is the correct way of doing this? Storing a bullet for example until it is removed from the superview, should I store it another way? and another question is, when I remove a UIImageView from the superview, does that remove it from memory so its not using up system resources? Thank you for the help! (will update if I Think of other questions

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  • Bulk update & occasional insert (coredata) - Too slow

    - by Andrew
    Update: Currently looking into NSSET's minusSet links: http://stackoverflow.com/questions/1475636/comparing-two-arrays Hi guys, Could benefit from your wisdom here.. I'm using Coredata in my app, on first launch I download a data file and insert over 500 objects (each with 60 attributes) - fast, no problem. Each subsequent launch I download an updated version of the file, from which I need to update all existing objects' attributes (except maybe 5 attributes) and create new ones for items which have been added to the downloaded file. So, first launch I get 500 objects.. say a week later my file now contains 507 items.. I create two arrays, one for existing and one for downloaded. NSArray *peopleArrayDownloaded = [CoreDataHelper getObjectsFromContext:@"person" :@"person_id" :YES :managedObjectContextPeopleTemp]; NSArray *peopleArrayExisting = [CoreDataHelper getObjectsFromContext:@"person" :@"person_id" :YES :managedObjectContextPeople]; If the count of each array is equal then I just do this: NSUInteger index = 0; if ([peopleArrayExisting count] == [peopleArrayDownloaded count]) { NSLog(@"Number of people downloaded is same as the number of people existing"); for (person *existingPerson in peopleArrayExisting) { person *tempPerson = [peopleArrayDownloaded objectAtIndex:index]; // NSLog(@"Updating id: %@ with id: %@",existingPerson.person_id,tempPerson.person_id); // I have 60 attributes which I to update on each object, is there a quicker way other than overwriting existing? index++; } } else { NSLog(@"Number of people downloaded is different to number of players existing"); So now comes the slow part. I end up using this (which is tooooo slow): NSLog(@"Need people added to the league"); for (person *tempPerson in peopeArrayDownloaded) { NSPredicate *predicate = [NSPredicate predicateWithFormat:@"person_id = %@",tempPerson.person_id]; // NSLog(@"Searching for existing person, person_id: %@",existingPerson.person_id); NSArray *filteredArray = [peopleArrayExisting filteredArrayUsingPredicate:predicate]; if ([filteredArray count] == 0) { NSLog(@"Couldn't find an existing person in the downloaded file. Adding.."); person *newPerson = [NSEntityDescription insertNewObjectForEntityForName:@"person" inManagedObjectContext:managedObjectContextPeople]; Is there a way to generate a new array of index items referring to the additional items in my downloaded file? Incidentally, on my tableViews I'm using NSFetchedResultsController so updating attributes will call [cell setNeedsDisplay]; .. about 60 times per cell, not a good thing and it can crash the app. Thanks for reading :)

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  • No warning from gcc when function definition in linked source different from function prototype in h

    - by c_c
    Hi, I had a problem with a part of my code, which after some iterations seemed to read NaN as value of a int of a struct. I think I found the error, but am still wondering why gcc (version 3.2.3 on a embedded Linux with busybox) did not warn me. Here are the important parts of the code: A c file and its header for functions to acquire data over USB: // usb_control.h typedef struct{ double mean; short *values; } DATA_POINTS; typedef struct{ int size; DATA_POINTS *channel1; //....7 more channels } DATA_STRUCT; DATA_STRUCT *create_data_struct(int N); // N values per channel int free_data_struct(DATA_STRUCT *data); int aqcu_data(DATA_STRUCT *data, int N); A c and header file with helper function (math, bitshift,etc...): // helper.h int mean(DATA_STRUCT *data); // helper.c (this is where the error is obviously) double mean(DATA_STRUCT *data) { // sum in for loop data->channel1->mean = sum/data->N; // ...7 more channels // a printf here displayed the mean values corretly } The main file // main.c #include "helper.h" #include "usb_control.h" // Allocate space for data struct DATA_STRUCT *data = create_data_struct(N); // get data for different delays for (delay = 0; delay < 500; delay += pw){ acqu_data(data, N); mean(data); // printf of the mean values first is correct. Than after 5 iterations // it is always NaN for channel1. The other channels are displayed correctly; } There were no segfaults nor any other missbehavior, just the NaN for channel1 in the main file. After finding the error, which was not easy, it was of course east to fix. The return type of mean(){} was wrong in the definition. Instead of double mean() it has to be int mean() as the prototype defines. When all the functions are put into one file, gcc warns me that there is a redefinition of the function mean(). But as I compile each c file seperately and link them afterwards gcc seems to miss that. So my questions would be. Why didn't I get any warnings, even non with gcc -Wall? Or is there still another error hidden which is just not causing problems now? Regards, christian

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  • How to ensure structures are completly initialized (by name) in GCC?

    - by Steven Spark
    How do I ensure each and every field of my structures are initialized in GCC when using designated initializers? (I'm especially interested in function pointers.) (I'm using C not C++.) Here is an example: typedef struct { int a; int b; } foo_t; typedef struct { void (*Start)(void); void (*Stop)(void); } bar_t; foo_t fooo = { 5 }; foo_t food = { .b=4 }; bar_t baro = { NULL }; bar_t bard = { .Start = NULL }; -Wmissing-field-initializers does not help at all. It works for fooo only in GCC (mingw 4.7.3, 4.8.1), and clang does only marginally better (no warnings for food and bard). I'm sure there is a reason for not producing warnings for designated initializer (even when I explicitly ask for them) but I want/need them. I do not want to initialize structures based on order/position because that is more error prone (for example swapping Start and Stop won't even give any warning). And neither gcc nor clang will give any warning that I failed to explicitly initialize a field (when initializing by name). I also don't want to litter my code with if(x.y==NULL) lines for multiple reasons, one of which is I want compile time warnings and not runtime errors. At least splint will give me warnings on all 4 cases, but unfortunately I cannot use splint all the time (it chokes on some of the code (fails to parse some C99, GCC extensions)). Note: If I'm using a real function instead of NULL GCC will also show a warning for baro (but not bard). I searched google and stack overflow but only found related questions and have not found answer for this specific problem. The best match I have found is 'Ensure that all elements in a structure are initialized' Ensure that all elements in a structure are initialized Which asks pretty much the same question, but has no satisfying answer. Is there a better way dealing with this that I have not mentioned? (Maybe other code analysis tool? Preferably something (free) that can be integrated into Eclipse or Visual Studio...)

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  • Is it OK to put a standard, pure C header #include directive inside a namespace?

    - by mic_e
    I've got a project with a class log in the global namespace (::log). So, naturally, after #include <cmath>, the compiler gives an error message each time I try to instantiate an object of my log class, because <cmath> pollutes the global namespace with lots of three-letter methods, one of them being the logarithm function log(). So there are three possible solutions, each having their unique ugly side-effects. Move the log class to it's own namespace and always access it with it's fully qualified name. I really want to avoid this because the logger should be as convenient as possible to use. Write a mathwrapper.cpp file which is the only file in the project that includes <cmath>, and makes all the required <cmath> functions available through wrappers in a namespace math. I don't want to use this approach because I have to write a wrapper for every single required math function, and it would add additional call penalty (cancelled out partially by the -flto compiler flag) The solution I'm currently considering: Replace #include <cmath> by namespace math { #include "math.h" } and then calculating the logarithm function via math::log(). I have tried it out and it does, indeed, compile, link and run as expected. It does, however, have multiple downsides: It's (obviously) impossible to use <cmath>, because the <cmath> code accesses the functions by their fully qualified names, and it's deprecated to use in C++. I've got a really, really bad feeling about it, like I'm gonna get attacked and eaten alive by raptors. So my question is: Is there any recommendation/convention/etc that forbid putting include directives in namespaces? Could anything go wrong with diferent C standard library implementations (I use glibc), different compilers (I use g++ 4.7, -std=c++11), linking? Have you ever tried doing this? Are there any alternate ways to banish the math functions from the global namespace? I've found several similar questions on stackoverflow, but most were about including other C++ headers, which obviously is a bad idea, and those that weren't made contradictory statements about linking behaviour for C libraries. Also, would it be beneficial to additionally put the #include <math.h> inside extern "C" {}?

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  • template; operator (int)

    - by Oops
    Hi, regarding my Point struct already mentioned here: http://stackoverflow.com/questions/2794369/template-class-ctor-against-function-new-c-standard is there a chance to replace the function toint() with a cast-operator (int)? namespace point { template < unsigned int dims, typename T > struct Point { T X[ dims ]; //umm??? template < typename U > Point< dims, U > operator U() const { Point< dims, U > ret; std::copy( X, X + dims, ret.X ); return ret; } //umm??? Point< dims, int > operator int() const { Point<dims, int> ret; std::copy( X, X + dims, ret.X ); return ret; } //OK Point<dims, int> toint() { Point<dims, int> ret; std::copy( X, X + dims, ret.X ); return ret; } }; //struct Point template < typename T > Point< 2, T > Create( T X0, T X1 ) { Point< 2, T > ret; ret.X[ 0 ] = X0; ret.X[ 1 ] = X1; return ret; } }; //namespace point int main(void) { using namespace point; Point< 2, double > p2d = point::Create( 12.3, 34.5 ); Point< 2, int > p2i = (int)p2d; //äähhm??? std::cout << p2d.str() << std::endl; char c; std::cin >> c; return 0; } I think the problem is here that C++ cannot distinguish between different return types? many thanks in advance. regards Oops

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  • rake db:create not working for legacy rails app (2.3.5) using MySQL (5.5.28)

    - by ridicter
    I'm a new Rails Developer, and I'm working on a legacy Rails app. Whenever I run the rake db:create command, I get an error that the database couldn't be created. I have found many StackOverflow questions related to this, but in troubleshooting nearly all permutations of solutions, I couldn't resolve the issue. I created the three Dbs (dev, prod, test), created the user with all access privileges to these dbs, and ran rake db:create. I'm running Mac OS X Lion, MySQL 5.5.28, Rails 2.3.5, Ruby 1.8.7. Here are my settings development: adapter: mysql encoding: utf8 database: adva_development username: adva password: **** host: localhost socket: /tmp/mysql.sock Here's the error: Couldn't create database for {"adapter"=>"mysql", "username"=>"adva", "host"=>"localhost", "encoding"=>"utf8", "database"=>"adva_development", "socket"=>"/tmp/mysql.sock", "password"=>"****"}, charset: utf8, collation: utf8_unicode_ci (if you set the charset manually, make sure you have a matching collation) I have done the following troubleshooting: Verified user and password are correct, and the user has access to the DB. (Double checked user access with SELECT * FROM mysql.db WHERE Db = 'adva_development' \G; User has all privileges.) Verify the socket is correct. I don't really understand sockets, but I can plainly see it at /tmp/mysql.sock. Checked collation and character set. I found out I had created the DB in latin charset and collation, so I recreated them. I ran show variables like "collation_database"; and show variables like "character_set_database"; and came back with utf8 and utf8_unicode_ci respectively. I followed the instructions in this question. After uninstalling mysql gem, I ran the following but came up with the same error: gem install --no-rdoc --no-ri mysql -- --with-mysql-dir=/usr/local/mysql-5.5.28-osx10.6-x86_64/bin --with-mysql-config=/usr/local/mysql-5.5.28-osx10.6-x86_64/bin/mysql_config Following Matt's suggestion, here's what a rake --trace db:create reveals: ** Invoke db:create (first_time) ** Invoke db:load_config (first_time) ** Invoke rails_env (first_time) ** Execute rails_env ** Execute db:load_config ** Execute db:create Couldn't create database for {"database"=>"adva_development", "adapter"=>"mysql", "host"=>"127.0.0.1", "password"=>"woof2adva", "username"=>"adva", "encoding"=>"utf8"}, charset: utf8, collation: utf8_unicode_ci (if you set the charset manually, make sure you have a matching collation) After 3 days and six or seven hours, I have pretty much run out of options. I tried various random things, like replacing localhost with 127.0.0.1 to no avail. Could there be something wrong related to my specific environment? Mac OS X Lion + MySQL 5.5.28? I plan on trying on setting up everything in a Linux environment. Thanks!

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  • Can I avoid a threaded UDP socket in Pyton dropping data?

    - by 666craig
    First off, I'm new to Python and learning on the job, so be gentle! I'm trying to write a threaded Python app for Windows that reads data from a UDP socket (thread-1), writes it to file (thread-2), and displays the live data (thread-3) to a widget (gtk.Image using a gtk.gdk.pixbuf). I'm using queues for communicating data between threads. My problem is that if I start only threads 1 and 3 (so skip the file writing for now), it seems that I lose some data after the first few samples. After this drop it looks fine. Even by letting thread 1 complete before running thread 3, this apparent drop is still there. Apologies for the length of code snippet (I've removed the thread that writes to file), but I felt removing code would just prompt questions. Hope someone can shed some light :-) import socket import threading import Queue import numpy import gtk gtk.gdk.threads_init() import gtk.glade import pygtk class readFromUDPSocket(threading.Thread): def __init__(self, socketUDP, readDataQueue, packetSize, numScans): threading.Thread.__init__(self) self.socketUDP = socketUDP self.readDataQueue = readDataQueue self.packetSize = packetSize self.numScans = numScans def run(self): for scan in range(1, self.numScans + 1): buffer = self.socketUDP.recv(self.packetSize) self.readDataQueue.put(buffer) self.socketUDP.close() print 'myServer finished!' class displayWithGTK(threading.Thread): def __init__(self, displayDataQueue, image, viewArea): threading.Thread.__init__(self) self.displayDataQueue = displayDataQueue self.image = image self.viewWidth = viewArea[0] self.viewHeight = viewArea[1] self.displayData = numpy.zeros((self.viewHeight, self.viewWidth, 3), dtype=numpy.uint16) def run(self): scan = 0 try: while True: if not scan % self.viewWidth: scan = 0 buffer = self.displayDataQueue.get(timeout=0.1) self.displayData[:, scan, 0] = numpy.fromstring(buffer, dtype=numpy.uint16) self.displayData[:, scan, 1] = numpy.fromstring(buffer, dtype=numpy.uint16) self.displayData[:, scan, 2] = numpy.fromstring(buffer, dtype=numpy.uint16) gtk.gdk.threads_enter() self.myPixbuf = gtk.gdk.pixbuf_new_from_data(self.displayData.tostring(), gtk.gdk.COLORSPACE_RGB, False, 8, self.viewWidth, self.viewHeight, self.viewWidth * 3) self.image.set_from_pixbuf(self.myPixbuf) self.image.show() gtk.gdk.threads_leave() scan += 1 except Queue.Empty: print 'myDisplay finished!' pass def quitGUI(obj): print 'Currently active threads: %s' % threading.enumerate() gtk.main_quit() if __name__ == '__main__': # Create socket (IPv4 protocol, datagram (UDP)) and bind to address socketUDP = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) host = '192.168.1.5' port = 1024 socketUDP.bind((host, port)) # Data parameters samplesPerScan = 256 packetsPerSecond = 1200 packetSize = 512 duration = 1 # For now, set a fixed duration to log data numScans = int(packetsPerSecond * duration) # Create array to store data data = numpy.zeros((samplesPerScan, numScans), dtype=numpy.uint16) # Create queue for displaying from readDataQueue = Queue.Queue(numScans) # Build GUI from Glade XML file builder = gtk.Builder() builder.add_from_file('GroundVue.glade') window = builder.get_object('mainwindow') window.connect('destroy', quitGUI) view = builder.get_object('viewport') image = gtk.Image() view.add(image) viewArea = (1200, samplesPerScan) # Instantiate & start threads myServer = readFromUDPSocket(socketUDP, readDataQueue, packetSize, numScans) myDisplay = displayWithGTK(readDataQueue, image, viewArea) myServer.start() myDisplay.start() gtk.gdk.threads_enter() gtk.main() gtk.gdk.threads_leave() print 'gtk.main finished!'

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  • is this aes encryption wrapper safe ? - yet another take...

    - by user393087
    After taking into accound answers for my questions here and here I created (well may-be) improved version of my wrapper. The key issue was what if an attacker is knowing what is encoded - he might then find the key and encode another messages. So I added XOR before encryption. I also in this version prepend IV to the data as was suggested. sha256 on key is only for making sure the key is as long as needed for the aes alg, but I know that key should not be plain text but calculated with many iterations to prevent dictionary attack function aes192ctr_en($data,$key) { $iv = mcrypt_create_iv(24,MCRYPT_DEV_URANDOM); $xor = mcrypt_create_iv(24,MCRYPT_DEV_URANDOM); $key = hash_hmac('sha256',$key,$iv,true); $data = $xor.((string)$data ^ (string)str_repeat($xor,(strlen($data)/24)+1)); $data = hash('md5',$data,true).$data; return $iv.mcrypt_encrypt('rijndael-192',$key,$data,'ctr',$iv); } function aes192ctr_de($data,$key) { $iv = substr($data,0,24); $data = substr($data,24); $key = hash_hmac('sha256',$key,$iv,true); $data = mcrypt_decrypt('rijndael-192',$key,$data,'ctr',$iv); $md5 = substr($data,0,16); $data = substr($data,16); if (hash('md5',$data,true)!==$md5) return false; $xor = substr($data,0,24); $data = substr($data,24); $data = ((string)$data ^ (string)str_repeat($xor,(strlen($data)/24)+1)); return $data; } $encrypted = aes192ctr_en('secret text','password'); echo $encrypted; echo aes192ctr_de($encrypted,'password'); another question is if ctr mode is ok in this context, would it be better if I use cbc mode ? Again, by safe I mean if an attacter could guess password if he knows exact text that was encrypted and knows above method. I assume random and long password here. Maybe instead of XOR will be safer to random initial data with another run of aes or other simpler alg like TEA or trivium ?

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  • Portrait video to landscape

    - by dappa
    I am aware questions like this one may already be out there but for the sake of others like me I will go ahead and ask I have a app that is set to only allow portrait orientation but this setting affects my videos as I would like only the videos to be able to play in landscape also. Is there a method I can add unto my .m file to make this work? Here is my code; #import "BIDVideosViewController.h" @interface BIDVideosViewController () @end @implementation BIDVideosViewController @synthesize moviePlayer ; @synthesize tableList; - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { // Custom initialization } return self; } - (void)viewDidLoad { [super viewDidLoad]; UITableView *table = [[UITableView alloc]initWithFrame:self.view.bounds]; [table setDelegate:self]; [table setDataSource:self]; [self.view addSubview:table]; tableList = [[NSMutableArray alloc] initWithObjects:@"Gangan",@"SwimGood",@"German Ice", nil]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } -(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [tableList count]; } -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *DisclosureButtonIdentifier = @"DisclosurebutotonIdentifier"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:DisclosureButtonIdentifier]; if (cell == nil) { cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:DisclosureButtonIdentifier]; } NSInteger row = [indexPath row]; NSString *rowString = [tableList objectAtIndex:row]; cell.textLabel.text = rowString; return cell; } -(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { { NSBundle *str = [tableList objectAtIndex:indexPath.row]; if ([str isEqual:@"Gangan"]) { NSBundle *bundle = [NSBundle mainBundle]; NSString *thePath = [bundle pathForResource:@"Gangan" ofType:@"mp4"]; NSURL *theurl = [NSURL fileURLWithPath:thePath]; moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:theurl]; [moviePlayer setMovieSourceType:MPMovieSourceTypeFile]; [self.view addSubview:moviePlayer.view]; [moviePlayer setFullscreen:YES]; [moviePlayer play]; } else if ([str isEqual:@"SwimGood"]) { NSBundle *bundle = [NSBundle mainBundle]; NSString *thePath = [bundle pathForResource:@"SwimGood" ofType:@"mp4"]; NSURL *theurl = [NSURL fileURLWithPath:thePath]; moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:theurl]; [moviePlayer setMovieSourceType:MPMovieSourceTypeFile]; [self.view addSubview:moviePlayer.view]; [moviePlayer setFullscreen:YES]; [moviePlayer play]; } else if ([str isEqual:@"German Ice"]) { NSBundle *bundle = [NSBundle mainBundle]; NSString *thePath = [bundle pathForResource:@"German Ice" ofType:@"mp4"]; NSURL *theurl = [NSURL fileURLWithPath:thePath]; moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:theurl]; [moviePlayer setMovieSourceType:MPMovieSourceTypeFile]; [self.view addSubview:moviePlayer.view]; [moviePlayer setFullscreen:YES]; [moviePlayer play]; } } } @end

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  • Ruby on Rails: create records for multiple models with one form and one submit

    - by notblakeshelton
    I have a 3 models: quote, customer, and item. Each quote has one customer and one item. I would like to create a new quote, a new customer, and a new item in their respective tables when I press the submit button. I have looked at other questions and railscasts and either they don't work for my situation or I don't know how to implement them. I also want my index page to be the page where I can create everything. quote.rb class Quote < ActiveRecord::Base attr_accessible :quote_number has_one :customer has_one :item end customer.rb class Customer < ActiveRecord::Base #unsure of what to put here #a customer can have multiple quotes, so would i use: has_many :quotes #<----? end item.rb class Item < ActiveRecord::Base #also unsure about this #each item can also be in multiple quotes quotes_controller.rb class QuotesController < ApplicationController def index @quote = Quote.new @customer = Customer.new @item = item.new end def create @quote = Quote.new(params[:quote]) @quote.save @customer = Customer.new(params[:customer]) @customer.save @item = Item.new(params[:item]) @item.save end end items_controller.rb class ItemsController < ApplicationController def index end def new @item = Item.new end def create @item = Item.new(params[:item]) @item.save end end customers_controller.rb class CustomersController < ApplicationController def index end def new @customer = Customer.new end def create @customer = Customer.new(params[:customer]) @customer.save end end quotes/index.html.erb <%= form_for @quote do |f| %> <%= f.fields_for @customer do |builder| %> <%= label_tag :firstname %> <%= builder.text_field :firstname %> <%= label_tag :lastname %> <%= builder.text_field :lastname %> <% end %> <%= f.fields_for @item do |builder| %> <%= label_tag :name %> <%= builder.text_field :name %> <%= label_tag :description %> <%= builder.text_field :description %> <% end %> <%= label_tag :quote_number %> <%= f.text_field :quote_number %> <%= f.submit %> <% end %> When I try submitting that I get an error: Can't mass-assign protected attributes: item, customer So to try and fix it I updated the attr_accessible in quote.rb to include :item, :customer but then I get this error: Item(#) expected, got ActiveSupport::HashWithIndifferentAccess(#) Any help would be greatly appreciated.

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  • sqlite 3 opening issue

    - by anonymous
    I'm getting my data ,with several similar methods, from sqlite3 file like in following code: -(NSMutableArray *) getCountersByID:(NSString *) championID{ NSMutableArray *arrayOfCounters; arrayOfCounters = [[NSMutableArray alloc] init]; @try { NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *databasePath = [[[NSBundle mainBundle] resourcePath ]stringByAppendingPathComponent:@"DatabaseCounters.sqlite"]; BOOL success = [fileManager fileExistsAtPath:databasePath]; if (!success) { NSLog(@"cannot connect to Database! at filepath %@",databasePath); } else{ NSLog (@"SUCCESS getCountersByID!!"); } if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK){ NSString *tempString = [NSString stringWithFormat:@"SELECT COUNTER_ID FROM COUNTERS WHERE CHAMPION_ID = %@",championID]; const char *sql = [tempString cStringUsingEncoding:NSASCIIStringEncoding]; sqlite3_stmt *sqlStatement; int ret = sqlite3_prepare(database, sql, -1, &sqlStatement, NULL); if (ret != SQLITE_OK) { NSLog(@"Error calling sqlite3_prepare: %d", ret); } if(sqlite3_prepare_v2(database, sql, -1, &sqlStatement, NULL) == SQLITE_OK){ while (sqlite3_step(sqlStatement)==SQLITE_ROW) { counterList *CounterList = [[counterList alloc]init]; CounterList.counterID = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement,0)]; [arrayOfCounters addObject:CounterList]; } } else{ NSLog(@"problem with database prepare"); } sqlite3_finalize(sqlStatement); } else{ NSLog(@"problem with database openning %s",sqlite3_errmsg(database)); } } @catch (NSException *exception){ NSLog(@"An exception occured: %@", [exception reason]); } @finally{ sqlite3_close(database); return arrayOfCounters; } //end } then i'm getting access to data with this and other similar lines of code: myCounterList *MyCounterList = [[myCounterList alloc] init]; countersTempArray = [MyCounterList getCountersByID:"2"]; [countersArray addObject:[NSString stringWithFormat:@"%@",(((counterList *) [countersTempArray objectAtIndex:i]).counterID)]]; I'm getting a lot of data like image name and showing combination of them that depends on users input with such code: UIImage *tempImage = [UIImage imageNamed:[NSString stringWithFormat:@"%@_0.jpg",[countersArray objectAtIndex:0]]]; [championSelection setBackgroundImage:tempImage forState:UIControlStateNormal]; My problem: When i'm run my app for some time and get a lot of data it throws error: " problem with database openning unable to open database file - error = 24 (Too many open files)" My guess is that i'm opening my database every time when getCountersByID is called but not closing it. My question: Am i using right approach to open and close database that i use? Similar questions that have not helped me to solve this problem: unable to open database Sqlite Opening Error : Unable to open database UPDATE: I made assumption that error is showing up because i use this lines of code too much: NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *databasePath = [[[NSBundle mainBundle] resourcePath ]stringByAppendingPathComponent:@"DatabaseCounters.sqlite"]; BOOL success = [fileManager fileExistsAtPath:databasePath]; and ending up with error 24. So i made them global but sqlite3_errmsg shows same err 24, but app runs much faster now I'll try to debug my app, see what happens

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  • SQL version control methodology

    - by Tom H.
    There are several questions on SO about version control for SQL and lots of resources on the web, but I can't find something that quite covers what I'm trying to do. First off, I'm talking about a methodology here. I'm familiar with the various source control applications out there and I'm familiar with tools like Red Gate's SQL Compare, etc. and I know how to write an application to check things in and out of my source control system automatically. If there is a tool which would be particularly helpful in providing a whole new methodology or which have a useful and uncommon functionality then great, but for the tasks mentioned above I'm already set. The requirements that I'm trying to meet are: The database schema and look-up table data are versioned DML scripts for data fixes to larger tables are versioned A server can be promoted from version N to version N + X where X may not always be 1 Code isn't duplicated within the version control system - for example, if I add a column to a table I don't want to have to make sure that the change is in both a create script and an alter script The system needs to support multiple clients who are at various versions for the application (trying to get them all up to within 1 or 2 releases, but not there yet) Some organizations keep incremental change scripts in their version control and to get from version N to N + 3 you would have to run scripts for N-N+1 then N+1-N+2 then N+2-N+3. Some of these scripts can be repetitive (for example, a column is added but then later it is altered to change the data type). We're trying to avoid that repetitiveness since some of the client DBs can be very large, so these changes might take longer than necessary. Some organizations will simply keep a full database build script at each version level then use a tool like SQL Compare to bring a database up to one of those versions. The problem here is that intermixing DML scripts can be a problem. Imagine a scenario where I add a column, use a DML script to fill said column, then in a later version that column name is changed. Perhaps there is some hybrid solution? Maybe I'm just asking for too much? Any ideas or suggestions would be greatly appreciated though. If the moderators think that this would be more appropriate as a community wiki, please let me know. Thanks!

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  • jQuery reference to (this) does not work?

    - by FFish
    I have this href link with text either "attivo" or "non attivo" User can set the item to 'active' or 'closed' in the database with an ajax request $.post() I have 2 questions for these: I can't get the reference to $(this) to work.. I tried it with a normal link and it works, but not wrapped in if/else?? How can I prevent the user from clicking more than one time on the link and submitting several request? Is this a valid concern? Do I need some sort of a small timer or something? First I was thinking about a javascript confirm message, but that's pretty annoying for this function.. HTML: <dl id='album-list'> <dt id="dt-2">some title</dt> <dd id="dd-2"> some description<br /> <div class='links-right'>status: <a class='toggle-active' href='#'>non attivo</a></div> </dd> </dl> <a class="test" href="#">test</a> JS: $('dd a.toggle-active').click(function() { var a_ref = $(this); var id = a_ref.parent().parent().attr('id').substring(3); if (a_ref.text() == "non attivo") { var new_active = "active"; // for db in english $.post("ajax-aa.php", {album_id:id, album_active:new_active}, function(data) { // alert("success"); a_ref.text("non attivo"); // change href text }); } else { var new_active = "closed"; // for db in english $.post("ajax-aa.php", {album_id:id, album_active:new_active}, function(data) { // alert("success"); a_ref.text("attivo"); // change href text }); } return false; }); $('a.test').click(function() { var a_ref = $(this); $.post("ajax-aa.php", {album_id:2, album_active:"active"}, function(data) { a_ref.text("changed"); }); return false; })

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  • Sliding through divs at interval - jQuery

    - by phil
    Hey, I have a list of around 30 divs (see below.) and would like to hear any suggestions on the best way to rotate through them by sliding in one at the top and removing one from the bottom at a set time. Something like every 5-10 seconds. Also even though there are 30 on the page I would only like to show a list of 10 and have the rest show as mentioned. A great example would be www.foursquare.com and their recent activity section. I would like to do the same except with a predetermined amount of divs instead of real-time using ajax. Any suggestions or a bit of help pointing me in the right direction would be greatly appreciated. <div class="recent-questions"> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> <div class="recent-question"></div> </div> Thanks in advance for any help or thoughts!

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  • Weird seg fault problem

    - by bluedaemon
    Greetings, I'm having a weird seg fault problem. My application dumps a core file at runtime. After digging into it I found it died in this block: #include <lib1/c.h> ... x::c obj; obj.func1(); I defined class c in a library lib1: namespace x { struct c { c(); ~c(); void fun1(); vector<char *> _data; }; } x::c::c() { } x::c::~c() { for ( int i = 0; i < _data.size(); ++i ) delete _data[i]; } I could not figure it out for some time till I ran nm on the lib1.so file: there are more function definitions than I defined: x::c::c() x::c::c() x::c::~c() x::c::~c() x::c::func1() x::c::func2() After searching in code base I found someone else defined a class with same name in same namespace, but in another library lib2 as follows: namespace x { struct c { c(); ~c(); void func2(); vector<string> strs_; }; } x::c::c() { } x::c::~c() { } My application links to lib2, which has dependency on lib1. This interesting behavior brings several questions: Why would it even work? I would expect a "multiple definitions" error while linking against lib2 (which depends upon lib1) but never had such. The application seems to be doing what's defined in func1 except it dumps a core at runtime. After attaching debugger, I found my application calls the ctor of class c in lib2, then calls func1 (defined in lib1). When going out of scope it calls dtor of class c in lib2, where the seg fault occurs. Can anybody teach me how this could even occur? How can I prevent such problems from happening again? Is there any C++ syntax I can use? Forgot to mention I'm using g++ 4.1 on RHEL4, thank you very much!

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  • Why does obj.getBounds().height give a larger height than obj.height?

    - by TC
    I'm new to Flash and ActionScript, but managing quite nicely. One thing that is continuously getting in my way are the width and height properties of DisplayObject(Container)s. I'm finally starting to get my head around them and learned that the width and height of a Sprite are determined solely by their contents for example. I do not understand the following though: I've got a Sprite that I add a bunch of Buttons to. The buttons all have a height of 30 and an y of 0. As such, I'd expect the height of the containing Sprite to be 30. Surprisingly, the height is 100. The Adobe documentation of the height property of a DisplayObject states: Indicates the height of the display object, in pixels. The height is calculated based on the bounds of the content of the display object. Apparently, the 'bounds' of the object are important. So I went ahead and wrote this little test in the Sprite that contains the Buttons: for (var i:int = 0; i < numChildren; ++i) { trace("Y: " + getChildAt(i).y + " H: " + getChildAt(i).height); trace("BOUNDS H: " + getChildAt(i).getBounds(this).height); } trace("SCALEY: " + scaleY + " TOTAL HEIGHT: " + height); This code iterates through all the objects that are added to its display list and shows their y, height and getBounds().height values. Surprisingly, the output is: Y: 0 H: 30 BOUNDS H: 100 ... (5x) SCALEY: 1 TOTAL HEIGHT: 100 This shows that the bounds of the buttons are actually larger than their height (and the height that they appear to be, visually). I have no clue why this is the case however. So my questions are: Why are the bounds of my buttons larger than their height? How can I set the bounds of my buttons so that my Sprite isn't larger than I'd expect it to be based on the position and size of the objects it contains? By the way, the buttons are created as follows: var control:Button = new Button(); control.setSize(90, 30); addChild(control);

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  • Different data for different dates

    - by nsw1475
    I am making a web page which will allow users to input and view data for different dates, and to change the date, there are two buttons, one of which will display the previous day, and one which will show the next day. I know that I can do this by submitting forms and reloading the page every time they press one of these buttons, but I would rather use javascript and not have to submit a form, but I am having troubles getting it to work. Currently, I have the two buttons, and the date stored in a PHP variable, as shown in my code below: <script> function init() { <? $nutrDate = $this->parseDate(date('m/d/Y')); ?> } function nutrPrevDay() { <? $nutrDate = mktime(0, 0, 0, date('m',$nutrDate), date('d',$nutrDate)-1, date('Y',$nutrDate)); ?> alert("<? echo(date("m/d/y", $nutrDate)) ?>"); } function nutrNextDay() { <? $nutrDate = mktime(0, 0, 0, date('m',$nutrDate), date('d',$nutrDate)+1, date('Y',$nutrDate)); ?> } window.onload = init; </script> <p style="text-align:center; font-size:14px; color:#03F"> <button onclick="nutrPrevDay()" style="width:200px" >< Show Previous Day</button> <? echo(date('m/d/Y', $nutrDate)) ?> <button onclick="nutrNextDay()" style="width:200px">Show Next Day ></button> </p> I have the alert in the nutrPrevDay() only as debugging. What happens is when I click on the button, the alert shows that the day is correctly decreased (for example from May 17 to May 16), but only decreases one day, and not one day for every click. Also, I do not know how to make the text on the page (created by the line ) change to display the new date after a button is clicked. So here are my questions: 1) Is it possible to dynamically change data (such as text, and in the future, SQL queries) on a page using javascript without having to reload a page when clicking on a button? 2) If possible, how can I make those changes? 3) How can I fix this so that it will increment and decrement through dates every time a button is clicked?

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  • PHP - trying to automate/loop a save function

    - by Homer_J
    EDIT: the difference between the pages are the simply $q1, $q2, $q3 becomes, for example, $q13, $q14, $q15 - they are questions in the form. Hi all, I have the following code: $rguid = $_POST["r"]; $ip=substr($_SERVER['REMOTE_ADDR'], 0, 50); $browser=substr($_SERVER['HTTP_USER_AGENT'], 0, 255); $q1 = $_POST["q1"]; $q2 = $_POST["q2"]; $q3 = $_POST["q3"]; $q4 = $_POST["q4"]; $q5 = $_POST["q5"]; $q6 = $_POST["q6"]; $q7 = $_POST["q7"]; $q8 = $_POST["q8"]; $respondent_id = decode_respondent_guid($rguid); $rcount=respondent_status($respondent_id); if ($rcount==0) { $proc = mysqli_prepare($link, "INSERT INTO tresults (respondent_id, ip, browser, q1, q2, q3, q4, q5, q6, q7, q8) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);"); mysqli_stmt_bind_param($proc, "issiiiiiiii", $respondent_id, $ip, $browser, $q1, $q2, $q3, $q4, $q5, $q6, $q7, $q8); mysqli_stmt_execute($proc); $mysql_error = mysqli_error($link); if ($mysql_error!="") { printf("Unexpected database error: %s\n", $mysql_error); mysqli_stmt_close($proc); mysqli_clean_connection($link); exit(); } else { mysqli_stmt_close($proc); mysqli_clean_connection($link); update_completion_status($respondent_id, 'Started'); header("Location: page2.php?r=".$rguid); } } This code works a treat - no problem. At the moment, that code appears on a 'save' page that relates to a 'form' page (i.e. if I have 5 .php pages with a form on each, I need 5 save.php pages to save each pages data to the database) to save data to my SQL database. What I would like is to have a single save.php page that will work with as many 'form' pages as I have. So instead of manually having to setup and change each save page, it automates it. I've no idea of the coding to do this, though I suspect something like a foreacg or loop etc. Any suggestions? Thanks, Homer.

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  • The big last_insert_id() problem, again.

    - by wretrOvian
    Note - this follows my question here: http://stackoverflow.com/questions/2983685/jdbc-does-the-connection-break-if-i-lose-reference-to-the-connection-object Now i have a created a class so i can deal with JDBC easily for the rest of my code - public class Functions { private String DB_SERVER = ""; private String DB_NAME = "test"; private String DB_USERNAME = "root"; private String DB_PASSWORD = "password"; public Connection con; public PreparedStatement ps; public ResultSet rs; public ResultSetMetaData rsmd; public void connect() throws java.io.FileNotFoundException, java.io.IOException, SQLException, Exception { String[] dbParms = Parameters.load(); DB_SERVER = dbParms[0]; DB_NAME = dbParms[1]; DB_USERNAME = dbParms[2]; DB_PASSWORD = dbParms[3]; // Connect. Class.forName("com.mysql.jdbc.Driver").newInstance(); con = DriverManager.getConnection("jdbc:mysql://" + DB_SERVER + "/" + DB_NAME, DB_USERNAME, DB_PASSWORD); } public void disconnect() throws SQLException { // Close. con.close(); } } As seen Parameters.load() refreshes the connection parameters from a file every-time, so that any changes to the same may be applied on the next immediate connection. An example of this class in action - public static void add(String NAME) throws java.io.FileNotFoundException, java.io.IOException, SQLException, Exception { Functions dbf = new Functions(); dbf.connect(); String query = "INSERT INTO " + TABLE_NAME + "(" + "NAME" + ") VALUES(?)"; PreparedStatement ps = dbf.con.prepareStatement(query); ps.setString(1, NAME); ps.executeUpdate(); dbf.disconnect(); } Now here is the problem - for adding a record to the table above, the add() method will open a connection, add the record - and then call disconnect() . What if i want to get the ID of the inserted record after i call add() -like this : Department.add("new dept"); int ID = getlastID(); Isn't it possible that another add() was called between those two statements?

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  • Users and roles in context

    - by Eric W.
    I'm trying to get a sense of how to implement the user/role relationships for an application I'm writing. The persistence layer is Google App Engine's datastore, which places some interesting (but generally beneficial) constraints on what can be done. Any thoughts are appreciated. It might be helpful to keep things very concrete. I would like there to be organizations, users, test content and test administrations (records of tests that have been taken). A user can have the role of participant (test-taker), contributor of test material or both. A user can also be a member of zero or more organizations. In the role of participant, the user can see the previous administrations of tests he or she has taken. The user can also see a test administration of another participant if that participant has given the user authorization. The user can see test material that has been made public, and he or she can see restricted content as a participant during a specific administration of a test for which that user has been authorized by an organization. As a member of an organization, the user can see restricted content in the role of contributor, and he or she might or might not also be able to edit the content. Each organization should have one or more administrators that can determine whether a member can see and edit content and determine who has admin privileges. There should also be one or more application-wide superusers that can troubleshoot and solve problems. Members of organizations can see the administrations of tests that the participants concerned have authorized them to see, and they can see anonymous data if no authorization has been given. A user cannot see the test results of another user in any other circumstances. Since there are no joins in the App Engine datastore, it might be necessary to have things less normalized than usual for the typical SQL database in order to ensure that queries that check permissions are fast (e.g., ones that determine whether a link is to be displayed). My questions are: How do I move forward on this? Should I spend a lot of time up front in order to get the model right, or can I iterate several times and gradually roll in additional complexity? Does anyone have some general ideas about how to break things up in this instance? Are there any GAE libraries that handle roles in a way that is compatible with this arrangement?

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  • Large Data Table with first column fixed

    - by bhavya_w
    I have structure as shown in the fiddle http://jsfiddle.net/5LN7U/. <section class="container"> <section class="field"> <ul> <li> Question 1 </li> <li> question 2 </li> <li> question 3 </li> <li> question 4 </li> <li> question 5 </li> <li> question 6 </li> <li> question 7 </li> </ul> </section> <section class="datawrap"> <section class="datawrapinner"> <ul> <li><b>Answer 1 :</b></li> <li><b>Answer 2 :</b></li> <li><b>Answer 3 :</b></li> <li><b>Answer 4 :</b></li> <li><b>Answer 5 :</b></li> <li><b>Answer 6 :</b></li> <li><b>Answer 7 :</b></li> </ul> </section> </section> </section> Basically its a table structure made using divs. The first column contains a long list of questions and the second column contains answers/multiple answers which can be quite big ( there has to be horizontal scrolling in the second column.) The problem i am facing is when i scroll downwards the second column which has the horizontal scroll bar is also scrolling downward. I want horizontal scrollbar to be fixed there. as in it should be always fixed there no matter how much i scroll vertically. Much Like Google Spreadsheets: where the first column stays fixed and there's horizontal scrolling on rest of the columns with over vertical scrolling for whole of the data. I cannot used position fixed in the second column. P.S : please no lectures on using div's for making a table structure. I have my own reasons. and its kinda urgent. Thanks in advance.

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  • Boost MultiIndex - objects or pointers (and how to use them?)?

    - by Sarah
    I'm programming an agent-based simulation and have decided that Boost's MultiIndex is probably the most efficient container for my agents. I'm not a professional programmer, and my background is very spotty. I've two questions: Is it better to have the container contain the agents (of class Host) themselves, or is it more efficient for the container to hold Host *? Hosts will sometimes be deleted from memory (that's my plan, anyway... need to read up on new and delete). Hosts' private variables will get updated occasionally, which I hope to do through the modify function in MultiIndex. There will be no other copies of Hosts in the simulation, i.e., they will not be used in any other containers. If I use pointers to Hosts, how do I set up the key extraction properly? My code below doesn't compile. // main.cpp - ATTEMPTED POINTER VERSION ... #include <boost/multi_index_container.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/mem_fun.hpp> #include <boost/tokenizer.hpp> typedef multi_index_container< Host *, indexed_by< // hash by Host::id hashed_unique< BOOST_MULTI_INDEX_MEM_FUN(Host,int,Host::getID) > // arg errors here > // end indexed_by > HostContainer; ... int main() { ... HostContainer testHosts; Host * newHostPtr; newHostPtr = new Host( t, DOB, idCtr, 0, currentEvents ); testHosts.insert( newHostPtr ); ... } I can't find a precisely analogous example in the Boost documentation, and my knowledge of C++ syntax is still very weak. The code does appear to work when I replace all the pointer references with the class objects themselves. As best I can read it, the Boost documentation (see summary table at bottom) implies I should be able to use member functions with pointer elements.

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