Search Results

Search found 24721 results on 989 pages for 'int tostring'.

Page 374/989 | < Previous Page | 370 371 372 373 374 375 376 377 378 379 380 381  | Next Page >

  • Simple binary File I/O problem with cstdio(c++)

    - by Atilla Filiz
    The c++ program below fails to read the file. I know using cstdio is not good practice but that what I am used to and it should work anyway. $ ls -l l.uyvy -rw-r--r-- 1 atilla atilla 614400 2010-04-24 18:11 l.uyvy $ ./a.out l.uyvy Read 0 bytes out of 614400, possibly wrong file code: #include<cstdio> int main(int argc, char* argv[]) { FILE *fp; if(argc<2) { printf("usage: %s <input>\n",argv[0]); return 1; } fp=fopen(argv[1],"rb"); if(!fp) { printf("erör, cannot open %s for reading\n",argv[1]); return -1; } int bytes_read=fread(imgdata,1,2*IMAGE_SIZE,fp); //2bytes per pixel fclose(fp); if(bytes_read < 2*IMAGE_SIZE) { printf("Read %d bytes out of %d, possibly wrong file\n", bytes_read, 2*IMAGE_SIZE); return -1; } return 0; }

    Read the article

  • problem with kCFSocketReadCallBack

    - by zp26
    Hello. I have a problem with my program. I created a socket with "kCFSocketReadCallBack. My intention was to call the "acceptCallback" only when it receives a string to the socket. Instead my program does not just accept the connection always goes into "startReceive" stop doing so and sometimes crash the program. Can anybody help? Thanks readSocket = CFSocketCreateWithNative( NULL, fd, kCFSocketReadCallBack, AcceptCallback, &context ); static void AcceptCallback(CFSocketRef s, CFSocketCallBackType type, CFDataRef address, const void *data, void *info) // Called by CFSocket when someone connects to our listening socket. // This implementation just bounces the request up to Objective-C. { ServerVistaController * obj; #pragma unused(address) // assert(address == NULL); assert(data != NULL); obj = (ServerVistaController *) info; assert(obj != nil); #pragma unused(s) assert(s == obj->listeningSocket); if (type & kCFSocketAcceptCallBack){ [obj acceptConnection:*(int *)data]; } if (type & kCFSocketAcceptCallBack){ [obj startReceive:*(int *)data]; } } -(void)startReceive:(int)fd { CFReadStreamRef readStream = NULL; CFIndex bytes; UInt8 buffer[MAXLENGTH]; CFStreamCreatePairWithSocket( kCFAllocatorDefault, fd, &readStream, NULL); if(!readStream){ close(fd); [self updateLabel:@"No readStream"]; } CFReadStreamOpen(readStream); [self updateLabel:@"OpenStream"]; bytes = CFReadStreamRead( readStream, buffer, sizeof(buffer)); if (bytes < 0) { [self updateLabel:(NSString*)buffer]; close(fd); } CFReadStreamClose(readStream); }

    Read the article

  • Strict pointer aliasing: is access through a 'volatile' pointer/reference a solution?

    - by doublep
    On the heels of a specific problem, a self-answer and comments to it, I'd like to understand if it is a proper solution, workaround/hack or just plain wrong. Specifically, I rewrote code: T x = ...; if (*reinterpret_cast <int*> (&x) == 0) ... As: T x = ...; if (*reinterpret_cast <volatile int*> (&x) == 0) ... with a volatile qualifier to the pointer. Let's just assume that treating T as int in my situation makes sense. Does this accessing through a volatile reference solve pointer aliasing problem? For a reference, from specification: [ Note: volatile is a hint to the implementation to avoid aggressive optimization involving the object because the value of the object might be changed by means undetectable by an implementation. See 1.9 for detailed semantics. In general, the semantics of volatile are intended to be the same in C++ as they are in C. — end note ] EDIT: The above code did solve my problem at least on GCC 4.5.

    Read the article

  • Load Testing Java Web Application - find TPS / Avg transaction response time

    - by Steve
    I would like to build my own load testing tool in Java with the goal of being able to load test a web application I am building throughout the development cycle. The web application will be receiving server to server HTTP Post requests and I would like to find its starting transaction per second (TPS) capacity along with the avgerage response time. The Post request and response messages will be in XML (I dont' think that's really applicable though :) ). I have written a very simple Java app to send transactions and count how many transactions it was able to send in one second (1000 ms) however I don't think this is the best way to load test. Really what I want is to send any number of transactions at exactly the same time - i.e. 10, 50, 100 etc. Any help would be appreciated! Oh and here is my current test app code: Thread[] t = new Thread[1]; for (int a = 0; a < t.length; a++) { t[a] = new Thread(new MessageLoop()); } startTime = System.currentTimeMillis(); System.out.println(startTime); for (int a = 0; a < t.length; a++) { t[a].start(); } while ((System.currentTimeMillis() - startTime) < 1000 ) { } if ((System.currentTimeMillis() - startTime) > 1000 ) { for (int a = 0; a < t.length; a++) { t[a].interrupt(); } } long endTime = System.currentTimeMillis(); System.out.println(endTime); System.out.println("Total time: " + (endTime - startTime)); System.out.println("Total transactions: " + count); private static class MessageLoop implements Runnable { public void run() { try { //Test Number of transactions while ((System.currentTimeMillis() - startTime) < 1000 ) { // SEND TRANSACTION HERE count++; } } catch (Exception e) { } } }

    Read the article

  • C: incompatible types in assignment

    - by The.Anti.9
    I'm writing a program to check to see if a port is open in C. One line in particular copies one of the arguments to a char array. However, when I try to compile, it says: error: incompatible types in assignment Heres the code. The error is on the assignment of addr #include <sys/socket.h> #include <sys/time.h> #include <sys/types.h> #include <arpa/inet.h> #include <netinet/in.h> #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <netdb.h> #include <stdlib.h> #include <string.h> #include <unistd.h> int main(int argc, char **argv) { u_short port; /* user specified port number */ char addr[1023]; /* will be a copy of the address entered by u */ struct sockaddr_in address; /* the libc network address data structure */ short int sock = -1; /* file descriptor for the network socket */ port = atoi(argv[1]); addr = strncpy(addr, argv[2], 1023); bzero((char *)&address, sizeof(address)); /* init addr struct */ address.sin_addr.s_addr = inet_addr(addr); /* assign the address */ address.sin_port = htons(port); /* translate int2port num */ sock = socket(AF_INET, SOCK_STREAM, 0); if (connect(sock,(struct sockaddr *)&address,sizeof(address)) == 0) { printf("%i is open\n", port); } if (errno == 113) { fprintf(stderr, "Port not open!\n"); } close(sock); return 0; } I'm new to C, so I'm not sure why it would do this.

    Read the article

  • Calling Object Methods in Code

    - by Mister R2
    I'm a bit new to PHP, and I'm more experienced with strongly-typed languages such as JAVA, C# or C++.I'm currently writing a web tool in PHP, and I am having an issue trying to do what I want. The simple idea of what I want to do in code is run through some emails I used PHP-IMAP to get. I then create email objects (a class I defined), and put them in an array. Later on the code, however, I cycle through those emails to display them. However, as you might have guessed I'd have an issue with, I try to use an Email Class object method in that later loop -- and I'm pretty sure PHP doesn't know that the variables in the array happen to be Email Class objects! I wrote a toString method, and I want to call it in the loop. While I don't need to do this for the final version of this tool, I would like to find out what I'm missing. This is the class and the loop where I'm calling the method: include 'imap_email_interface.php'; class ImapEmail implements imap_email_interface { // Email data var $msgno; var $to; var $from; var $subject; var $body; var $attachment; // Email behavior /* PHP 4 ~ legacy constructor */ public function ImapEmail($message_number) { $this->__construct(); $this->msgno = $message_number; } /* PHP 5 Constructor */ public function __construct($message_number) { $this->msgno = $message_number; } public function send($send_to) { // Not Yet Needed! Seriously! } public function setHeaderDirectly($TO, $FROM, $SUBJECT) { $this->to = $TO; $this->from = $FROM; $this->subject = $SUBJECT; } public function setHeaderIndirectly($HEADER) { if (isset($HEADER->to[0]->personal)) $this->to = '"'.$HEADER->to[0]->personal.'", '.$HEADER->to[0]->mailbox.'@'.$HEADER->to[0]->host; else $this->to = $HEADER->to[0]->mailbox.'@'.$HEADER->to[0]->host; $this->from = '"'.$HEADER->from[0]->personal.'", '.$HEADER->from[0]->mailbox.'@'.$HEADER->from[0]->host; $this->subject = $HEADER->subject; } public function setBody($BODY) { $this->body = $BODY; } public function setAttachment($ATTCH) { $this->attachment = $ATTCH; } public function toString() { $str = '[TO]: ' . $this->to . '<br />' . '[FROM]: ' . $this->from . '<br />' . '[SUBJECT]: ' . $this->subject . '<br />'; $str .= '[Attachment]: '.$this->attachment.'<br />'; return $str; } } ?> The Loop: foreach ($orderFileEmails as $x) { $x->toString(); echo '<br /><br />'; } Any ideas?

    Read the article

  • Android Parcelable create array

    - by Ozik Abdullaev
    In background i parse JSON, and then in this background i send Json to parcelable And in Parcelable i writestring with JSONObject.optString how i can write ArrayList? List<Row> result = new ArrayList<Row>(array.length()); for (int i = 0; i < array.length(); i++) { result.add(new Row(array.optJSONObject(i))); } Parcelable.java public Row(JSONObject from) { thumb = from.optString(TAG_THUMBNAILS); bigImage = from.optString(TAG_BIG_IMAGE); author = from.optString(TAG_AUTHOR); description = from.optString(TAG_DESCRIPTION); date = from.optString(TAG_DATE); } public Row(Parcel parcel) { thumb = parcel.readString(); bigImage = parcel.readString(); author = parcel.readString(); description = parcel.readString(); date = parcel.readString(); } @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel parcel, int flags) { parcel.writeString(thumb); parcel.writeString(bigImage); parcel.writeString(author); parcel.writeString(description); parcel.writeString(date); }

    Read the article

  • Input questions mysql php html

    - by Marcelo
    (Q1)Hi I'm using textbox in my project and I can't receive the values that are typed <textarea rows="5" cols="60"> Type your suggestion </textarea> <br> <input type="submit" name="sugestao" value="Submit" /> Sorry I don't know how to 'kill' html code, that's why < is missing. All I'm getting in the column of the database from this text box is "Submit", I'd like to receive whatever is written in the text area. How can I make the value equal whaterever is typed? (Q2) How can I make sure that I'll only store the same type(int,varchar,text) that I setted,declared in the database. For example: age(int), but if someone types "abc" in the input it will be stored in my database as the value 0 . How can I forbid this, and only save the age when it's just int and all the other fields(like name, email) are filled ?. And if is still possible warn the user that he is typing something wrong, don't need to say where. Sorry for any mistake in English and Thanks for the attention.

    Read the article

  • XCode enum woes

    - by Raconteur
    Hi gang, I thought I had this sorted, but I am still missing something. Very simply, I have a Settings class that hold a DAO (sitting on a plist). I want to have a couple of enums for the settings for convenience and readability, such as GamePlayType and DifficultyLevel. Right now I am defining them in the Settings.h file above the @interface line as such: typedef enum { EASY, NORMAL, HARD } DifficultyLevel; and typedef enum { SET_NUMBER_OF_MOVES, TO_COMPLETION } GamePlayType; If I access them from within the Settings class like: - (int)gridSizeForLOD { switch ([self difficultyLevel]) { case EASY: return GRID_SIZE_EASY; case NORMAL: return GRID_SIZE_NORMAL; case HARD: return GRID_SIZE_HARD; default: return GRID_SIZE_NORMAL; } } everything is fine. But, if I try to access them outside of the Settings class, let's say in my main view controller class, like this: if (([settings gameType] == SET_NUMBER_OF_MOVES) && (numMoves == [settings numMovesForLOD])) { [self showLoseScreen]; } I get errors (like EXC_BAD_ACCESS) or the condition always fails. Am I doing something incorrectly? Also, I should point out that I have this code for the call to gameType (which lives in the Settings class): - (GamePlayType)gameType { return [dao gameType]; } and the DAO implements gameType like this: - (int)gameType { return (settingsContent != nil) ? [[settingsContent objectForKey:@"Game Type"] intValue] : 0; } I know I have the DAO returning an int instead of a GamePlayType, but A) the problem I am describing arose there when I tried to use the "proper" data type, and B) I did not think it would matter since the enum is just a bunch of named ints, right? Any help, greatly appreciated. I really want to understand this thoroughly, and something is eluding me... Cheers, Chris

    Read the article

  • identifier ... is undefined when trying to run pure C code in Cuda using nvcc

    - by Lostsoul
    I'm new and learning Cuda. A approach that I'm trying to use to learn is to write code in C and once I know its working start converting it to Cuda since I read that nvcc compiles Cuda code but complies everything else using plain old c. My code works in c(using gcc) but when I try to compile it using nvcc(after changing the file name from main.c to main.cu) I get main.cu(155): error: identifier "num_of_rows" is undefined main.cu(155): error: identifier "num_items_in_row" is undefined 2 errors detected in the compilation of "/tmp/tmpxft_00002898_00000000-4_main.cpp1.ii". Basically in my main method I send data to a function like this: process_list(count, countListItem, list); the first two items are ints and the last item(list) is a matrix. Then I create my function like this: void process_list(int num_of_rows, int num_items_in_row, int current_list[num_of_rows][num_items_in_row]) { This line is where I get my errors when using nvcc(line 155). I need to convert this code to cuda anyway so no need to troubleshoot this specific issue(plus code is quite large) but I'm wondering if I'm wrong about nvcc treating the C part of your code like plain C. In the book cuda by example I just used nvcc to compile but do I need any extra flags when just using pure c?

    Read the article

  • Suggestions for a django db structure

    - by rh0dium
    Hi Say I have the unknown number of questions. For example: Is the sky blue [y/n] What date were your born on [date] What is pi [3.14] What is a large integ [100] Now each of these questions poses a different but very type specific answer (boolean, date, float, int). Natively django can happily deal with these in a model. class SkyModel(models.Model): question = models.CharField("Is the sky blue") answer = models.BooleanField(default=False) class BirthModel(models.Model): question = models.CharField("What date were your born on") answer = models.DateTimeField(default=today) class PiModel(models.Model) question = models.CharField("What is pi") answer = models.FloatField() But this has the obvious problem in that each question has a specific model - so if we need to add a question later I have to change the database. Yuck. So now I want to get fancy - How do a set up a model where by the answer type conversion happens automagically? ANSWER_TYPES = ( ('boolean', 'boolean'), ('date', 'date'), ('float', 'float'), ('int', 'int'), ('char', 'char'), ) class Questions(models.model): question = models.CharField(() answer = models.CharField() answer_type = models.CharField(choices = ANSWER_TYPES) default = models.CharField() So in theory this would do the following: When I build up my views I look at the type of answer and ensure that I only put in that value. But when I want to pull that answer back out it will return the data in the format specified by the answer_type. Example 3.14 comes back out as a float not as a str. How can I perform this sort of automagic transformation? Or can someone suggest a better way to do this? Thanks much!!

    Read the article

  • Understanding C++ pointers (when they point to a pointer)

    - by Stephano
    I think I understand references and pointers pretty well. Here is what I (think I) know: int i = 5; //i is a primitive type, the value is 5, i do not know the address. int *ptr; //a pointer to an int. i have no way if knowing the value yet. ptr = &i; //now i have an address for the value of i (called ptr) *ptr = 10; //go get the value stored at ptr and change it to 10 Please feel free to comment or correct these statements. Now I'm trying to make the jump to arrays of pointers. Here is what I do not know: char **char_ptrs = new char *[50]; Node **node_ptrs = new Node *[50]; My understanding is that I have 2 arrays of pointers, one set of pointers to chars and one to nodes. So if I wanted to set the values, I would do something like this: char_ptrs[0] = new char[20]; node_ptrs[0] = new Node; Now I have a pointer, in the 0 position of my array, in each respective array. Again, feel free to comment here if I'm confused. So, what does the ** operator do? Likewise, what is putting a single * next to the instantiation doing (*[50])? (what is that called exactly, instantiation?)

    Read the article

  • Classes and Objects in C++

    - by anurag18294
    class anurag { private: int rollno; char name[50]; int marks; float percen; void percentage(int num) { percen=(num/500)*100; } public: void getdata(void) { cout<<"\n\nEnter the name of the student:"; gets(name); cout<<"\n\nEnter the roll no: and the marks:"; cin>>rollno>>marks; percentage(marks); } void display(void) { cout<<"\n\nThe name of the student is:"; cout.write(name,50); cout<<"\n\nThe roll no: of the student is:"; cout<<rollno; cout<<"\n\n The marks obtained is:"<<marks; cout<<"\n\nThe percentage is:"<<percen; }}; void main() { clrscr(); anurag F; F.getdata(); F.display(); getch(); } why the following code is not giving the desired output?

    Read the article

  • Retruning reference to object not changing the address in c++

    - by ashish-sangwan
    I am trying to understand function returning reference. For that i have written a simple program :- include using namespace std; class test { int i; friend test& func(); public: test(int j){i=j;} void show(){cout< }; test& func() { test temp(10); return temp; //// Address of temp=0xbfcb2874 } int main() { test obj1(50); // Address of obj1=0xbfcb28a0 func()=obj1; <= Problem:The address of obj1 is not changing obj1.show(); // // Address of obj1=0xbfcb28a0 return 0; } I run the program using gdb and observed that the address of obj1 still remains same but i expect it to get changed to 0xbfcb2874. I am not clear with the concept. Please help. Thanks in advance

    Read the article

  • Returning reference to object is not changing the address in c++

    - by ashish-sangwan
    I am trying to understand functions returning a reference. For that I have written a simple program: #include<iostream> using namespace std; class test { int i; friend test& func(); public: test(int j){i=j;} void show(){cout<<i<<endl;} }; test& func() { test temp(10); return temp; //// Address of temp=0xbfcb2874 } int main() { test obj1(50); // Address of obj1=0xbfcb28a0 func()=obj1; <= Problem:The address of obj1 is not changing obj1.show(); // // Address of obj1=0xbfcb28a0 return 0; } I ran the program using gdb and observed that the address of obj1 still remains same, but I expect it to get changed to 0xbfcb2874. I am not clear with the concept. Please help.

    Read the article

  • this is my first time asking here, I wanted to create a linked list while sorting it thanks

    - by user2738718
    package practise; public class Node { // node contains data and next public int data; public Node next; //constructor public Node (int data, Node next){ this.data = data; this.next = next; } //list insert method public void insert(Node list, int s){ //case 1 if only one element in the list if(list.next == null && list.data > s) { Node T = new Node(s,list); } else if(list.next == null && list.data < s) { Node T = new Node(s,null); list.next = T; } //case 2 if more than 1 element in the list // 3 elements present I set prev to null and curr to list then performed while loop if(list.next.next != null) { Node curr = list; Node prev = null; while(curr != null) { prev = curr; curr = curr.next; if(curr.data > s && prev.data < s){ Node T = new Node(s,curr); prev.next = T; } } // case 3 at the end checks for the data if(prev.data < s){ Node T = new Node(s,null); prev.next = T; } } } } // this is a hw problem, i created the insert method so i can check and place it in the correct order so my list is sorted This is how far I got, please correct me if I am wrong, I keep inserting node in the main method, Node root = new Node(); and root.insert() to add.

    Read the article

  • Is there any point in using a volatile long?

    - by Adamski
    I occasionally use a volatile instance variable in cases where I have two threads reading from / writing to it and don't want the overhead (or potential deadlock risk) of taking out a lock; for example a timer thread periodically updating an int ID that is exposed as a getter on some class: public class MyClass { private volatile int id; public MyClass() { ScheduledExecutorService execService = Executors.newScheduledThreadPool(1); execService.scheduleAtFixedRate(new Runnable() { public void run() { ++id; } }, 0L, 30L, TimeUnit.SECONDS); } public int getId() { return id; } } My question: Given that the JLS only guarantees that 32-bit reads will be atomic is there any point in ever using a volatile long? (i.e. 64-bit). Caveat: Please do not reply saying that using volatile over synchronized is a case of pre-optimisation; I am well aware of how / when to use synchronized but there are cases where volatile is preferable. For example, when defining a Spring bean for use in a single-threaded application I tend to favour volatile instance variables, as there is no guarantee that the Spring context will initialise each bean's properties in the main thread.

    Read the article

  • Does Interlocked guarantee visibility to other threads in C# or do I still have to use volatile?

    - by Lirik
    I've been reading the answer to a similar question, but I'm still a little confused... Abel had a great answer, but this is the part that I'm unsure about: ...declaring a variable volatile makes it volatile for every single access. It is impossible to force this behavior any other way, hence volatile cannot be replaced with Interlocked. This is needed in scenarios where other libraries, interfaces or hardware can access your variable and update it anytime, or need the most recent version. Does Interlocked guarantee visibility of the atomic operation to all threads, or do I still have to use the volatile keyword on the value in order to guarantee visibility of the change? Here is my example: public class CountDownLatch { private volatile int m_remain; // <--- do I need the volatile keyword there since I'm using Interlocked? private EventWaitHandle m_event; public CountDownLatch (int count) { Reset(count); } public void Reset(int count) { if (count < 0) throw new ArgumentOutOfRangeException(); m_remain = count; m_event = new ManualResetEvent(false); if (m_remain == 0) { m_event.Set(); } } public void Signal() { // The last thread to signal also sets the event. if (Interlocked.Decrement(ref m_remain) == 0) m_event.Set(); } public void Wait() { m_event.WaitOne(); } }

    Read the article

  • How can i get a file from remote machine?

    - by programmerist
    How can i get a file from remote computer? i know remote computer ip and 51124 port is open. i need this algorith: 1) Connect 192.xxx.x.xxx ip via 51124 port 2) filename:123456 (i want to search it on remote machine) 3) Get File 4) Save C:\ 51124 port is open. can i access and can i search any file according to filename? My code is below: IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, 51124); Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP); sock.Bind(ipEnd); sock.Listen(maxConnections); Socket serverSocket = sock.Accept(); byte[] data = new byte[bufferSize]; int received = serverSocket.Receive(data); int filenameLength = BitConverter.ToInt32(data, 0); string filename = Encoding.ASCII.GetString(data, 4, filenameLength); BinaryWriter bWrite = new BinaryWriter(File.Open(outPath + filename, FileMode.Create)); bWrite.Write(data, filenameLength + 4, received - filenameLength - 4); int received2 = serverSocket.Receive(data); while (received2 0) { bWrite.Write(data, 0, received2); received2 = serverSocket.Receive(data); } bWrite.Close(); serverSocket.Close(); sock.Close();

    Read the article

  • Table index design

    - by Swoosh
    I would like to add index(s) to my table. I am looking for general ideas how to add more indexes to a table. Other than the PK clustered. I would like to know what to look for when I am doing this. So, my example: This table (let's call it TASK table) is going to be the biggest table of the whole application. Expecting millions records. IMPORTANT: massive bulk-insert is adding data in this table table has 27 columns: (so far, and counting :D ) int x 9 columns = id-s varchar x 10 columns bit x 2 columns datetime x 5 columns INT COLUMNS all of these are INT ID-s but from tables that are usually smaller than Task table (10-50 records max), example: Status table (with values like "open", "closed") or Priority table (with values like "important", "not so important", "normal") there is also a column like "parent-ID" (self - ID) join: all the "small" tables have PK, the usual way ... clustered STRING COLUMNS there is a (Company) column (string!) that is something like "5 characters long all the time" and every user will be restricted using this one. If in Task there are 15 different "Companies" the logged in user would only see one. So there's always a filter on this one. Might be a good idea to add an index to this column? DATE COLUMNS I think they don't index these ... right? Or can / should be?

    Read the article

  • Pointing to array element

    - by regular
    What I'm trying to achieve is say i have an array, i want to be able to modify a specific array element throughout my code, by pointing at it. for example in C++ i can do this int main(){ int arr [5]= {1,2,3,4,5}; int *c = &arr[3]; cout << arr[3] <<endl; *c = 0; cout << arr[3]<<endl; } I did some googling and there seems to be a way to do it through 'unsafe', but i don't really want to go that route. I guess i could create a variable to store the indexes, but I'm actually dealing with slightly more complexity (a list within a list. so having two index variables seems to add complexity to the code.) C# has a databinding class, so what I'm currently doing is binding the array element to a textbox (that i have hidden) and modifying that textbox whenever i want to modify the specific array element, but that's also not a good solution (since i have a textbox that's not being used for its intended purpose - a bit misleading).

    Read the article

  • Have something loaded only when JList item is visibile

    - by elvencode
    Hello, i'm implementing a Jlist populated with a lot of elements. Each element corresponds to a image so i'd like to show a resized preview of them inside each row of the list. I've implemented a custom ImageCellRenderer extending the Jlabel and on getListCellRendererComponent i create the thumbnail if there'snt any for that element. Each row corresponds to a Page class where i store the path of the image and the icon applied to the JLabel. Each Page object is put inside a DefaultListModel to populate the JList. The render code is something like this: public Component getListCellRendererComponent( JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) { Page page = (Page) value; if (page.getImgIcon() == null) { System.out.println(String.format("Creating thumbnail of %s", page.getImgFilename())); ImageIcon icon = new ImageIcon(page.getImgFilename()); int thumb_width = icon.getIconWidth() > icon.getIconHeight() ? 128 : ((icon.getIconWidth() * 128) / icon.getIconHeight()); int thumb_height = icon.getIconHeight() > icon.getIconWidth() ? 128 : ((icon.getIconHeight() * 128) / icon.getIconWidth()); icon.setImage(getScaledImage(icon.getImage(), thumb_width, thumb_height)); page.setImgIcon(icon); } setIcon(page.getImgIcon()); } I was thinking that only a certain item is visibile in the List the cell renderer is called but i'm seeing that all the thumnails are created when i add the Page object to the list model. I've tried to load the items and after set the model in the JList or set the model first and after starting appending the items but the results are the same. Is there any way to load the data only when necessary or do i need to create a custom control like a JScrollPanel with stacked items inside where i check myself the visibility of each elements? Thanks

    Read the article

  • C++ arrays as parameters, subscript vs. pointer

    - by awshepard
    Alright, I'm guessing this is an easy question, so I'll take the knocks, but I'm not finding what I need on google or SO. I'd like to create an array in one place, and populate it inside a different function. I define a function: void someFunction(double results[]) { for (int i = 0; i<100; ++i) { for (int n = 0; n<16; ++n) //note this iteration limit { results[n] += i * n; } } } That's an approximation to what my code is doing, but regardless, shouldn't be running into any overflow or out of bounds issues or anything. I generate an array: double result[16]; for(int i = 0; i<16; i++) { result[i] = -1; } then I want to pass it to someFunction someFunction(result); When I set breakpoints and step through the code, upon entering someFunction, results is set to the same address as result, and the value there is -1.000000 as expected. However, when I start iterating through the loop, results[n] doesn't seem to resolve to *(results+n) or *(results+n*sizeof(double)), it just seems to resolve to *(results). What I end up with is that instead of populating my result array, I just get one value. What am I doing wrong?

    Read the article

  • 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'?

    Read the article

  • Help ! How do I get the total number rows from my mssql paging procedure ?

    - by The_AlienCoder
    Ok I have a table in my MSSQL database that stores comments. My desire is to be able to page though the records using [Back],[Next], page numbers & [Last] buttons in my datalist. I figured the most efficient way was to use a stored procedure that only returns a certain number of rows within a partcular range. Here is what I came up with @PageIndex INT, @PageSize INT, @postid int AS SET NOCOUNT ON begin WITH tmp AS ( SELECT comments.*, ROW_NUMBER() OVER (ORDER BY dateposted ASC) AS Row FROM comments WHERE (comments.postid = @postid)) SELECT tmp.* FROM tmp WHERE Row between (@PageIndex - 1) * @PageSize + 1 and @PageIndex*@PageSize end RETURN Now everything works fine and I have been able implement [Next] and [Back] buttons in my datalist pager.Now I need the total number of all comments(not in the cuurent page) so that I can implement my page numbers and the[Last] button on my pager. In other words I want to return the total number of rows in my first select statement i.e WITH tmp AS ( SELECT comments.*, ROW_NUMBER() OVER (ORDER BY dateposted ASC) AS Row FROM comments WHERE (comments.postid = @postid)) set @TotalRows = @@rowcount @@rowcount doesnt work and raises an error.I also cant get count.* to work either. Is there another way to get the total amount of rows or is my approach doomed.

    Read the article

< Previous Page | 370 371 372 373 374 375 376 377 378 379 380 381  | Next Page >