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  • How to retrieve the Description property from SettingsProperty?

    - by BadNinja
    For each item in my application's settings, I've added text to its Description Property which I want to retrieve at runtime. I'm sure I'm missing some basic logical nuance here, but everything I've tried has failed. Clearly, my understanding of what value needs to be passed to the Attributes property of the SettingsProperty class is wrong. I'm further confused by the fact that when I iterate through all they keys returned by SettingsProperty.Attributes.Keys, I can see "System.Configuration.SettingsDescriptionAttribute", but when I pass that string in as the key to the Attributes property, null is returned. Any insight into how to properly retrieve the value Description Property would be very much appreciated. Thanks. :) public void MyMethod() { SettingsPropertyCollection MyAppProperties = Properties.Settings.Default.Properties; IEnumerator enumerator = MyAppProperties.GetEnumerator(); // Iterate through all the keys to see what we have.... while (enumerator.MoveNext()) { SettingsProperty property = (SettingsProperty)enumerator.Current; ICollection myKeys = property.Attributes.Keys; foreach (object theKey in myKeys) System.Diagnostics.Debug.Print(theKey.ToString()); // One of the keys returned is: System.Configuration.SettingsDescriptionAttribute } enumerator.Reset(); while (enumerator.MoveNext()) { SettingsProperty property = (SettingsProperty)enumerator.Current; string propertyValue = property.DefaultValue.ToString(); // This fails: Null Reference string propertyDescription = property.Attributes["System.Configuration.SettingsDescriptionAttribute"].ToString(); // Do stuff with strings... } }

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  • @PrePersist with entity inheritance

    - by gerry
    I'm having some problems with inheritance and the @PrePersist annotation. My source code looks like the following: _the 'base' class with the annotated updateDates() method: @javax.persistence.Entity @Inheritance(strategy = InheritanceType.TABLE_PER_CLASS) public class Base implements Serializable{ ... @Id @GeneratedValue protected Long id; ... @Column(nullable=false) @Temporal(TemporalType.TIMESTAMP) private Date creationDate; @Column(nullable=false) @Temporal(TemporalType.TIMESTAMP) private Date lastModificationDate; ... public Date getCreationDate() { return creationDate; } public void setCreationDate(Date creationDate) { this.creationDate = creationDate; } public Date getLastModificationDate() { return lastModificationDate; } public void setLastModificationDate(Date lastModificationDate) { this.lastModificationDate = lastModificationDate; } ... @PrePersist protected void updateDates() { if (creationDate == null) { creationDate = new Date(); } lastModificationDate = new Date(); } } _ now the 'Child' class that should inherit all methods "and annotations" from the base class: @javax.persistence.Entity @NamedQueries({ @NamedQuery(name=Sensor.QUERY_FIND_ALL, query="SELECT s FROM Sensor s") }) public class Sensor extends Entity { ... // additional attributes @Column(nullable=false) protected String value; ... // additional getters, setters ... } If I store/persist instances of the Base class to the database, everything works fine. The dates are getting updated. But now, if I want to persist a child instance, the database throws the following exception: MySQLIntegrityConstraintViolationException: Column 'CREATIONDATE' cannot be null So, in my opinion, this is caused because in Child the method "@PrePersist protected void updateDates()" is not called/invoked before persisting the instances to the database. What is wrong with my code?

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  • ArrayList<String> NullPointerException

    - by Carlucho
    Am trying to solve a labyrinth by DFS, using adj List to represent the vertices and edges of the graph. In total there are 12 nodes (3 rows[A,B,C] * 4 cols[0,..,3]). My program starts by saving all the vertex labels (A0,..C3), so far so good, then checks the adjacent nodes, also no problems, if movement is possible, it proceeds to create the edge, here its where al goes wrong. adjList[i].add(vList[j].label); I used the debugger and found that vList[j].label is not null it contains a correct string (ie. "B1"). The only variables which show null are in adjList[i], which leads me to believe i have implemented it wrongly. this is how i did it. public class GraphList { private ArrayList<String>[] adjList; ... public GraphList(int vertexcount) { adjList = (ArrayList<String>[]) new ArrayList[vertexCount]; ... } ... public void addEdge(int i, int j) { adjList[i].add(vList[j].label); //NULLPOINTEREXCEPTION HERE } ... } I will really appreaciate if anyone can point me on the right track regrading to what its going wrong... Thanks!

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  • diffuculty in appending images dynamically in an Custom List View

    - by ganesh
    Hi I have written an custom List view which binds images according to the result from a feed @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder; if (convertView == null) { convertView = mInflater.inflate(R.layout.row_for_stopnames, null); holder = new ViewHolder(); holder.name = (TextView)convertView.findViewById(R.id.stop_name); holder.dis = (TextView)convertView.findViewById(R.id.distance); holder.route_one=(ImageView)convertView.findViewById(R.id.one); holder.route_two=(ImageView)convertView.findViewById(R.id.two); holder.route_three=(ImageView)convertView.findViewById(R.id.three); convertView.setTag(holder); } else { holder = (ViewHolder) convertView.getTag(); } holder.name.setText(elements.get(position).get("stop_name")); holder.dis.setText(elements.get(position).get("distance")); String[] route_txt=elements.get(position).get("route_name").split(","); for(int i=0;i<route_txt.length;i++) { if(i==0) { holder.route_one.setBackgroundResource(Utils.getRouteImage().get(stop_txt[0])); } else if(i==1) { holder.route_two.setBackgroundResource(Utils.getRouteImage().get(stop_txt[1])); } else if(i==2) { holder.route_three.setBackgroundResource(Utils.getRouteImage().get(stop_txt[2])); } } convertView.setOnClickListener(new OnItemClickListener(position,elements)); return convertView; } class ViewHolder { TextView name; TextView dis; ImageView route_one; ImageView route_two; ImageView route_three; } for every stop name there may be route_names, maximum of three routes.I have to bind images according to the number of route names.This is what I tried to do by the above code .This works fine until I start scrolling up and down .When I do so the route images gets displayed where it does not want to be,this behaviour is unpredictable.I will be glad if someone explain me why this happens,and the best way to do this.The getRouteImage method of Utils class returns HashMap with key String and value a drawable

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  • WPF - data binding trigger before content changed

    - by 0xDEAD BEEF
    How do i create trigger, which fires BEFORE binding changes value? How to do this for datatemplate? <ContentControl Content="{Binding Path=ActiveView}" Margin="0,95,0,0"> <ContentControl.Triggers> <--some triger to fire, when ActiveView is changing or has changed ?!?!? --> </ContentControl.Triggers> public Object ActiveView { get { return m_ActiveView; } set { if (PropertyChanging != null) PropertyChanging(this, new PropertyChangingEventArgs("ActiveView")); m_ActiveView = value; if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("ActiveView")); } } How to do this for DataTemplate? <DataTemplate DataType="{x:Type us:LOLClass1}"> <ContentControl> <ContentControl.RenderTransform> <ScaleTransform x:Name="shrinker" CenterX="0.0" CenterY="0.0" ScaleX="1.0" ScaleY="1.0"/> </ContentControl.RenderTransform> <us:UserControl1/> </ContentControl> <DataTemplate.Triggers> <-- SOME TRIGER BEFORE CONTENT CHANGES--> <BeginStoryboard> <Storyboard> <DoubleAnimation Storyboard.TargetName="shrinker" Storyboard.TargetProperty="ScaleX" From="1.0" To="0.8" Duration="0:0:0.3"/> <DoubleAnimation Storyboard.TargetName="shrinker" Storyboard.TargetProperty="ScaleY" From="1.0" To="0.8" Duration="0:0:0.3"/> </Storyboard> </BeginStoryboard> </-- SOME TRIGER BEFORE CONTENT CHANGES--> </DataTemplate.Triggers> </DataTemplate> How to get notification BEFORE binding is changed? (i want to capture changing Visual component to bitmap and create sliding view animation)

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  • Fiscal year, quarters, student table, and faculty table... How do I relate these?!

    - by yuudachi
    I have a student and faculty table. The primary key for student is studendID (SID) and faculty's primary key is facultyID, naturally. Student has an advisor column and a requested advisor column, which are foreign key to faculty. That's simple enough, right? However, now I have to throw in dates. I want to be able to view who their advisor was for a certain quarter (such as 2009 Winter) and who they had requested. The result will be a table like this: Year | Term | SID | Current | Requested ------------------------------------------------ 2009 | Winter | 860123456 | 1 | NULL 2009 | Winter | 860445566 | 3 | NULL 2009 | Winter | 860369147 | 5 | 1 And then if I feel like it, I could also go ahead and view a different year and a different term. I am not sure how these new table(s) will look like. Will there be a year table with three columns that are Fall, Spring and Winter? And what will the Fall, Spring, Winter table have? I am new to the art of tables, so this is baffling me... Also, I feel I should clarify how the site works so far now. Admin can approve student requests, and what happens is that the student's current advisor gets overwritten with their request. However, I think I should not do that anymore, right?

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  • Should java try blocks be scoped as tightly as possible?

    - by isme
    I've been told that there is some overhead in using the Java try-catch mechanism. So, while it is necessary to put methods that throw checked exception within a try block to handle the possible exception, it is good practice performance-wise to limit the size of the try block to contain only those operations that could throw exceptions. I'm not so sure that this is a sensible conclusion. Consider the two implementations below of a function that processes a specified text file. Even if it is true that the first one incurs some unnecessary overhead, I find it much easier to follow. It is less clear where exactly the exceptions come from just from looking at statements, but the comments clearly show which statements are responsible. The second one is much longer and complicated than the first. In particular, the nice line-reading idiom of the first has to be mangled to fit the readLine call into a try block. What is the best practice for handling exceptions in a funcion where multiple exceptions could be thrown in its definition? This one contains all the processing code within the try block: void processFile(File f) { try { // construction of FileReader can throw FileNotFoundException BufferedReader in = new BufferedReader(new FileReader(f)); // call of readLine can throw IOException String line; while ((line = in.readLine()) != null) { process(line); } } catch (FileNotFoundException ex) { handle(ex); } catch (IOException ex) { handle(ex); } } This one contains only the methods that throw exceptions within try blocks: void processFile(File f) { FileReader reader; try { reader = new FileReader(f); } catch (FileNotFoundException ex) { handle(ex); return; } BufferedReader in = new BufferedReader(reader); String line; while (true) { try { line = in.readLine(); } catch (IOException ex) { handle(ex); break; } if (line == null) { break; } process(line); } }

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  • x509 certificate verification in C

    - by sid
    Hi All, I do have certificates in DER and PEM format, My goal is to retrieve the fields of Issuer and Subject And verify the Certificate with the CA public key and simultaneously verify CA certificate with the Root public key. I am able to retrieve all the details of issuer and subject But unable to verify the certificate. Please help. The API's used, x509 = d2i_X509_fp (fp, &x509); //READING DER Format x509 = PEM_read_X509 (fp, &x509, NULL, NULL); //READING PEM Format X509_NAME_oneline(X509_get_subject_name(x509), subject, sizeof (subject)); //to retrive the Subject X509_NAME_oneline(X509_get_issuer_name(x509), issuer, sizeof (issuer)); //to retrive the Issuer // to store the CA public key (in unsigned char *key)that will be used to verify the certificate (My case Always sha1WithRSAEncryption) RSA *x = X509_get_pubkey(x509)->pkey.rsa; bn = x->n; //extracts the bytes from public key & convert into unsigned char buffer buf_len = (size_t) BN_num_bytes (bn); stored_CA_pubKey = (unsigned char *)malloc (buf_len); i_n = BN_bn2bin (bn, (unsigned char *)stored_CA_pubKey); if (i_n != buf_len) LOG(ERROR," : key error\n"); if (key[0] & 0x80) LOG(DEBUG, "00\n"); stored_CA_pubKeyLen = EVP_PKEY_size(X509_get_pubkey(x509)); For Verification I went through different approaches but unable to verify a) i_x509_verify = X509_verify(cert_x509, ca_pubkey); b) /* verify the signature */ int iRet1, iRet2, iReason; iRet1 = EVP_VerifyInit(&md_ctx, EVP_sha1()); iRet2 = EVP_VerifyUpdate(&md_ctx, cert_code, cert_code_len); rv = EVP_VerifyFinal(&md_ctx, (const unsigned char *)stored_CA_pubKey, stored_CA_pubKeyLen, cert_pubkey); NOTE : cert_code & stored_CA_pubKey is unsigned char buffer. Thanks in Advance

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  • SQL: Order randomly when inserting objects to a table

    - by Ekaterina
    I have an UDF that selects top 6 objects from a table (with a union - code below) and inserts it into another table. (btw SQL 2005) So I paste the UDF below and what the code does is: selects objects for a specific city and add a level to those (from table Europe) union that selection with a selection from the same table for objects that are from the same country and add a level to those From the union, selection is made to get top 6 objects, order by level, so the objects from the same city will be first, and if there aren't any available, then objects from the same country will be returned from the selection. And my problem is, that I want to make a random selection to get random objects from table Europe, but because I insert the result of my selection into a table, I can't use order by newid() or rand() function because they are time-dependent, so I get the following errors: Invalid use of side-effecting or time-dependent operator in 'newid' within a function. Invalid use of side-effecting or time-dependent operator in 'rand' within a function. UDF: ALTER FUNCTION [dbo].[Objects] (@id uniqueidentifier) RETURNS @objects TABLE ( ObjectId uniqueidentifier NOT NULL, InternalId uniqueidentifier NOT NULL ) AS BEGIN declare @city varchar(50) declare @country int select @city = city, @country = country from Europe where internalId = @id insert @objects select @id, internalId from ( select distinct top 6 [level], internalId from ( select top 6 1 as [level], internalId from Europe N4 where N4.city = @city and N4.internalId != @id union select top 6 2 as [level], internalId from Europe N5 where N5.countryId = @country and N5.internalId != @id ) as selection_1 order by [level] ) as selection_2 return END If you have fresh ideas, please share them with me. (Just please, don't suggest to order by newid() or to add a column rand() with seed DateTime (by ms or sthg), because that won't work.)

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  • Linked list example using threads

    - by Carl_1789
    I have read the following code of using CRITICAL_SECTION when working with multiple threads to grow a linked list. what would be the main() part which uses two threads to add to linked list? #include <windows.h> typedef struct _Node { struct _Node *next; int data; } Node; typedef struct _List { Node *head; CRITICAL_SECTION critical_sec; } List; List *CreateList() { List *pList = (List*)malloc(sizeof(pList)); pList->head = NULL; InitializeCriticalSection(&pList->critical_sec); return pList; } void AddHead(List *pList, Node *node) { EnterCriticalSection(&pList->critical_sec); node->next = pList->head; pList->head = node; LeaveCriticalSection(&pList->critical_sec); } void Insert(List *pList, Node *afterNode, Node *newNode) { EnterCriticalSection(&pList->critical_sec); if (afterNode == NULL) { AddHead(pList, newNode); } else { newNode->next = afterNode->next; afterNode->next = newNode; } LeaveCriticalSection(&pList->critical_sec); } Node *Next(List *pList, Node *node) { Node* next; EnterCriticalSection(&pList->critical_sec); next = node->next; LeaveCriticalSection(&pList->critical_sec); return next; }

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  • What's the best way to resolve this scope problem?

    - by Peter Stewart
    I'm writing a program in python that uses genetic techniques to optimize expressions. Constructing and evaluating the expression tree is the time consumer as it can happen billions of times per run. So I thought I'd learn enough c++ to write it and then incorporate it in python using cython or ctypes. I've done some searching on stackoverflow and learned a lot. This code compiles, but leaves the pointers dangling. I tried 'this_node = new Node(...' . It didn't seem to work. And I'm not at all sure how I'd delete all the references as there would be hundreds. I'd like to use variables that stay in scope, but maybe that's not the c++ way. What is the c++ way? class Node { public: char *cargo; int depth; Node *left; Node *right; } Node make_tree(int depth) { depth--; if(depth <= 0) { Node tthis_node("value",depth,NULL,NULL); return tthis_node; } else { Node this_node("operator" depth, &make_tree(depth), &make_tree(depth)); return this_node; } };

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  • The uncatchable exception, pt 2

    - by chaiguy
    Ok I've done some testing and I've reduced the problem to something very simple: i. Create a method in a new class that throws an exception: public class Class1 { public void CallMe() { string blah = null; blah.ToLower(); } } ii. Create a MethodInfo that points to this method somewhere else: Type class1 = typeof( Class1 ); Class1 obj = new Class1(); MethodInfo method = class1.GetMethod( "CallMe" ); iii. Wrap a call to Invoke() in a try/catch block: try { method.Invoke( obj, null ); // exception is not being caught! } catch { } iv. Run the program without the debugger (works fine). v. Now run the program with the debugger. The debugger will halt the program when the exception occurs, even though it's wrapped in a catch handler that tries to ignore it. (Even if you put a breakpoint in the catch block it will halt before it reaches it!) In fact, the exception is happening when you run it without the debugger too. In a simple test project it's getting ignored at some other level, but if your app has any kind of global exception handling, it will get triggered there as well. This is causing me a real headache because it keeps triggering my app's crash-handler, not to mention the pain it is to attempt to debug.

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  • Ajax Auto Complete in ASP.Net MVC project - How to display a an object's name but actually save it's

    - by Ben
    I have implemented the Ajax Autocomplete feature in my application using a web service file that querys my database and it works great. One problem I am having is allowing the user to see the item's name, as that's what they are typing in the textbox, but when they select it, it saves the item's ID number instead of the actual name. I want it to behave much like a dropdown list, where I can specify what is seen and entered vs. what is actually saved in the database (in this case, the product ID instead of it's name.) I have this text box in my view, along with the script: <script type="text/javascript"> Sys.Application.add_init(function() { $create( AjaxControlToolkit.AutoCompleteBehavior, { serviceMethod: 'ProductSearch', servicePath: '/ProductService.asmx', minimumPrefixLength: 1, completionSetCount: 10 }, null, null, $get('ProductID')) }); </script> <p> <label for="ProductID">Product:</label> <%= Html.TextBox("ProductID", Model.Products)%> <%= Html.ValidationMessage("ProductID", "*")%> </p> Here's what is in my asmx file: public class ProductService : System.Web.Services.WebService { [WebMethod] public string[] ProductSearch(string prefixText, int count) { MyDataContext db = new MyDataContext(); string[] products = (from product in db.Products where product.ProductName.StartsWith(prefixText) select product.ProductName).Take(count).ToArray(); return products; } } Can anyone help me figure this out? I'm using this so they can just start typing instead of having a dropdown list that's a mile long...

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  • Deeply nested subqueries for traversing trees in MySQL

    - by nickf
    I have a table in my database where I store a tree structure using the hybrid Nested Set (MPTT) model (the one which has lft and rght values) and the Adjacency List model (storing parent_id on each node). my_table (id, parent_id, lft, rght, alias) This question doesn't relate to any of the MPTT aspects of the tree but I thought I'd leave it in in case anyone had a good idea about how to leverage that. I want to convert a path of aliases to a specific node. For example: "users.admins.nickf" would find the node with alias "nickf" which is a child of one with alias "admins" which is a child of "users" which is at the root. There is a unique index on (parent_id, alias). I started out by writing the function so it would split the path to its parts, then query the database one by one: SELECT `id` FROM `my_table` WHERE `parent_id` IS NULL AND `alias` = 'users';-- 1 SELECT `id` FROM `my_table` WHERE `parent_id` = 1 AND `alias` = 'admins'; -- 8 SELECT `id` FROM `my_table` WHERE `parent_id` = 8 AND `alias` = 'nickf'; -- 37 But then I realised I could do it with a single query, using a variable amount of nesting: SELECT `id` FROM `my_table` WHERE `parent_id` = ( SELECT `id` FROM `my_table` WHERE `parent_id` = ( SELECT `id` FROM `my_table` WHERE `parent_id` IS NULL AND `alias` = 'users' ) AND `alias` = 'admins' ) AND `alias` = 'nickf'; Since the number of sub-queries is dependent on the number of steps in the path, am I going to run into issues with having too many subqueries? (If there even is such a thing) Are there any better/smarter ways to perform this query?

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  • fastest way to crawl recursive ntfs directories in C++

    - by Peter Parker
    I have written a small crawler to scan and resort directory structures. It based on dirent(which is a small wrapper around FindNextFileA) In my first benchmarks it is surprisingy slow: around 123473ms for 4500 files(thinkpad t60p local samsung 320 GB 2.5" HD). 121481 files found in 123473 milliseconds Is this speed normal? This is my code: int testPrintDir(std::string strDir, std::string strPattern="*", bool recurse=true){ struct dirent *ent; DIR *dir; dir = opendir (strDir.c_str()); int retVal = 0; if (dir != NULL) { while ((ent = readdir (dir)) != NULL) { if (strcmp(ent->d_name, ".") !=0 && strcmp(ent->d_name, "..") !=0){ std::string strFullName = strDir +"\\"+std::string(ent->d_name); std::string strType = "N/A"; bool isDir = (ent->data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) !=0; strType = (isDir)?"DIR":"FILE"; if ((!isDir)){ //printf ("%s <%s>\n", strFullName.c_str(),strType.c_str());//ent->d_name); retVal++; } if (isDir && recurse){ retVal += testPrintDir(strFullName, strPattern, recurse); } } } closedir (dir); return retVal; } else { /* could not open directory */ perror ("DIR NOT FOUND!"); return -1; } }

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  • fgets in c don't return a portion of an string

    - by Marc
    Hi! I'm totally new in C, and I'm trying to do a little application that searches a string into a file, my problem is that I need to open a big file (more than 1GB) with just one line inside and fgets return me the entire file (I'm doing test with a 10KB file). actually this is my code: #include <stdio.h> #include <string.h> int main(int argc, char *argv[]) { char *search = argv[argc-1]; int retro = strlen(search); int pun = 0; int sortida; int limit = 10; char ara[20]; FILE *fp; if ((fp = fopen ("SEARCHFILE", "r")) == NULL){ sortida = -1; exit (1); } while(!feof(fp)){ if (fgets(ara, 20, fp) == NULL){ break; } //this must be a 20 bytes line, but it gets the entyre 10Kb file printf("%s",ara); } sortida = 1; if(fclose(fp) != 0){ sortida = -2; exit (1); } return 0; } What can I do to find an string into a file? I'v tried with GREP but it don't helps, because it returns the position:ENTIRE_STRING. I'm open to ideas. Thanks in advance!

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  • How to add objects to NSArray from a different class with ARC

    - by Space Dust
    I needed to convert my code to ARC. I have an NSArray that I use to draw a path. I fill the objects of NSArray values from a different class. Problem is after converting to ARC, NSArray returns always null I can not see what I am doing wrong. bug.h @interface Ladybug : CCSprite <CCTargetedTouchDelegate>{ CCArray *linePathPosition; } @property (nonatomic, strong) CCArray *linePathPosition; @end bug.m @synthesize linePathPosition; -(id) init { if( (self=[super init] )) { self.linePathPosition = [[CCArray alloc] init]; } return self; } -(void) updatePosition:(CGPoint) position { [self.linePathPosition addObject:[NSValue valueWithCGPoint:position]]; NSLog(@"line path %@",linePathPosition); } -(void) breakMoveLadyBug { [self.linePathPosition removeAllObjects]; } In main .m - (void)ccTouchMoved:(UITouch *)touch withEvent:(UIEvent *)event { Ladybug *ladybug1 = (Ladybug *)[self getChildByTag:99]; CCMotionStreak* streak = (CCMotionStreak *)[self getChildByTag:999]; CGPoint touchLocation = [touch locationInView: [touch view]]; CGPoint curPosition = [[CCDirector sharedDirector] convertToGL:touchLocation]; if (ladybug1.isSelected) { streak.position = curPosition; [ladybug1 updatePosition:curPosition]; NSLog(@"Cur position %@",NSStringFromCGPoint(curPosition)); if (!ladybug1.isMoving) { [ladybug1 startMoveLadyBug]; } } } Log: Cur position {331, 110} line path (null) What am I doing wrong? What is the proper way to define and init NSArray with ARC?

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  • help with mysql triggers (checking values before insert)

    - by user332817
    hi I'm quite new to mysql and I'm trying to figure out how to use triggers. what I'm trying to do: I have 2 tables, max and sub_max, when I insert a new row to sub_max I want to check if the SUM of the values with the same foreign_key as the new row are less than the value in the max table. I think this sounds confusing so here are my tables: CREATE TABLE max( number INT , MaxAmount integer NOT NULL) CREATE TABLE sub_max( sub_number INT , sub_MaxAmount integer NOT NULL, number INT, FOREIGN KEY ( number ) REFERENCES max( number )) and here is my code for the trigger, I know the syntax is off but this is the best I could do from looking up tutorials. CREATE TRIGGER maxallowed after insert on submax FOR EACH ROW BEGIN DECLARE submax integer; DECLARE maxmax integer; submax = select sum(sub_MaxAmount) from sub_max where sub_number = new.sub_number; submax = submax + new. sub_MaxAmount; maxmax = select MaxAmount from max where number = new.number ; if max>maxmax rollback? END I wanted to know if I'm doing this remotely correctly. Thanks in advance.

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  • Question about compilers and how they work

    - by Marin Doric
    This is the C code that frees memory of a singly linked list. It is compiled with Visual C++ 2008 and code works as it should be. /* Program done, so free allocated memory */ current = head; struct film * temp; temp = current; while (current != NULL) { temp = current->next; free(current); current = temp; } But I also encountered ( even in a books ) same code written like this: /* Program done, so free allocated memory */ current = head; while (current != NULL) { free(current); current = current->next; } If I compile that code with my VC++ 2008, program crashes because I am first freeing current and then assigning current-next to current. But obviously if I compile this code with some other complier ( for example, compiler that book author used ) program will work. So question is, why does this code compiled with specific compiler work? Is it because that compiler put instructions in binary file that remember address of current-next although I freed current and my VC++ doesn't. I just want to understand how compilers work.

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  • deactivate ' pin to start ' on Application List page when pinning an app via code using C#?

    - by Ahmed Ali
    i'm creating a windows phone app ,where i've put a button to pin the app to start screen , but when press and hold the app icon on application list screen i find that the pin to start option can be used ShellTile TileToFind = ShellTile.ActiveTiles.FirstOrDefault(x => x.NavigationUri.ToString().Contains("MainPage.xaml")); // Create the Tile if we didn't find that it already exists. if (TileToFind == null) { // Create the Tile object and set some initial properties for the Tile. // The Count value of 12 shows the number 12 on the front of the Tile. Valid values are 1-99. // A Count value of 0 indicates that the Count should not be displayed. StandardTileData NewTileData = new StandardTileData { BackgroundImage = new Uri("300.png", UriKind.Relative), Title = "apptitle", BackTitle = "title", BackContent = "testing ", BackBackgroundImage = null }; // Create the Tile and pin it to Start. This will cause a navigation to Start and a deactivation of our app. ShellTile.Create(new Uri("/MainPage.xaml", UriKind.Relative), NewTileData); } else { MessageBox.Show("Already Pinned"); } how can i disable the user from pinning the application again from application list screen

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  • How to avoid shell execution of a Process?

    - by adeel amin
    When I start a process like process = Runtime.getRuntime().exec("gnome-terminal");, it starts shell execution. I want to stop shell execution and want to redirect I/O from process, can anybody tell how I can do this? My code is: public void start_process() { try { process= Runtime.getRuntime().exec("gnome-terminal"); pw= new PrintWriter(process.getOutputStream(),true); br=new BufferedReader(new InputStreamReader(process.getInputStream())); err=new BufferedReader(new InputStreamReader(process.getErrorStream())); } catch (Exception ioe) { System.out.println("IO Exception-> " + ioe); } } public void execution_command() { if(check==2) { try { boolean flag=thread.isAlive(); if(flag==true) thread.stop(); Thread.sleep(30); thread = new MyReader(br,tbOutput,err,check); thread.start(); }catch(Exception ex){ JOptionPane.showMessageDialog(null, ex.getMessage()+"1"); } } else { try { Thread.sleep(30); thread = new MyReader(br,tbOutput,err,check); thread.start(); check=2; }catch(Exception ex){ JOptionPane.showMessageDialog(null, ex.getMessage()+"1"); } } } private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: command=tfCmd.getText().toString().trim(); pw.println(command); execution_command(); } When I enter some command in textfield and press execute button, nothing is displayed on my output textarea, how I can stop shell execution and redirect input and output?

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  • Remove duplicate records/objects uniquely identified by multiple attributes

    - by keruilin
    I have a model called HeroStatus with the following attributes: id user_id recordable_type hero_type (can be NULL!) recordable_id created_at There are over 100 hero_statuses, and a user can have many hero_statuses, but can't have the same hero_status more than once. A user's hero_status is uniquely identified by the combination of recordable_type + hero_type + recordable_id. What I'm trying to say essentially is that there can't be a duplicate hero_status for a specific user. Unfortunately, I didn't have a validation in place to assure this, so I got some duplicate hero_statuses for users after I made some code changes. For example: user_id = 18 recordable_type = 'Evil' hero_type = 'Halitosis' recordable_id = 1 created_at = '2010-05-03 18:30:30' user_id = 18 recordable_type = 'Evil' hero_type = 'Halitosis' recordable_id = 1 created_at = '2009-03-03 15:30:00' user_id = 18 recordable_type = 'Good' hero_type = 'Hugs' recordable_id = 1 created_at = '2009-02-03 12:30:00' user_id = 18 recordable_type = 'Good' hero_type = NULL recordable_id = 2 created_at = '2009-012-03 08:30:00' (Last two are not a dups obviously. First two are.) So what I want to do is get rid of the duplicate hero_status. Which one? The one with the most-recent date. I have three questions: How do I remove the duplicates using a SQL-only approach? How do I remove the duplicates using a pure Ruby solution? Something similar to this: http://stackoverflow.com/questions/2790004/removing-duplicate-objects. How do I put a validation in place to prevent duplicate entries in the future?

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  • codegen:nullValue vs msprop:nullValue

    - by Ken
    Ok, I have datasets that I created way back in 1.1 framework to which we used codegen:nullValue within the XSD to handle null values. However if I open one of these datasets with vs 2005 (i.e. 2.0 framework) and add a column, it removes the codegen setting from the entire xsd but adds in msprop:nullValue However, unlike previous years, I noticed this time the proper property code was NOT over riden from returning the null value specified in codegen as it was doing in the past. Meaning the msprop appears to be creating the proper code behind the scenes (See example). Anyone know of any other differnces? Should I be concerned with deploying a new xsd, WITHOUT the codegen code but instead with the msprop xml? Example: Original creates _ Public Property ParentID() As Integer Get If Me.IsParentIDNull Then Return -1 Else Return CType(Me(Me.tableCompany.ParentIDColumn),Integer) End If End Get Set Me(Me.tableCompany.ParentIDColumn) = value End Set End Property New creates _ Public Property ParentID() As Integer Get If Me.IsParentIDNull Then Return -1 Else Return CType(Me(Me.tableCompany.ParentIDColumn),Integer) End If End Get Set Me(Me.tableCompany.ParentIDColumn) = value End Set End Property BUT is there anything else that might be occuring that I am NOT seeing thus MAKING me re-enter all the codegen settings? THANKS!

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  • Validating Age field javascript beginner

    - by Marcelo
    Hi people, I'm trying to validate an age field in a form but I'm having some problem. First I tried to make sure that the field will not be send empty. I don't know javascript so I searched some scripts and adapted them to this: function isInteger (s) { var i; if (isEmpty(s)) if (isInteger.arguments.length == 1) return 0; else return (isInteger.arguments[1] == true); for (i = 0; i < s.length; i++) { var c = s.charAt(i); if (!isDigit(c)) return false; } return true; } function isEmpty(s) { return ((s == null) || (s.length == 0)) } function validate_required(field,alerttxt) { with (field) { if (value==null||value=="") { alert(alerttxt);return false; } else { return true; } } } function validate_form(thisform) { with (thisform) { if ((validate_required(age,"Age must be filled out!")==false) || isInteger(age,"Age must be and int number")==false)) {email.focus();return false;} } } //html part <form action="doador.php" onsubmit="return validate_form(this)" method="post"> It's working fine for empty fields, but if I type any letters or characters in age field, it'll be sent and saved a 0 in my database. Can any one help me ? Sorry for any mistake in English, and thanks in andvance for your help.

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  • ObjectDisposedException when .Show()'ing a form that shouldn't be disposed.

    - by user320781
    ive checked out some of the other questions and obviously the best solution is to prevent the behavior that causes this issue in the first place, but the problem is very intermittent, and very un-reproduceable. I basically have a main form, with sub forms. The sub forms are shown from menus and/or buttons from the main form like so: private void myToolStripMenuItem_Click(object sender, EventArgs e) { try { xDataForm.Show(); xDataForm.Activate(); } catch (ObjectDisposedException) { MessageBox.Show("ERROR 10103"); ErrorLogging newLogger = new ErrorLogging("10103"); Thread errorThread = new Thread(ErrorLogging.writeErrorToLog); errorThread.Start(); } } and the sub forms are actually in the main form(for better or worse. i would actually like to change this but would be a considerable amount of time to do so): public partial class FormMainScreen : Form { Form xDataForm = new xData(); ...(lots more here) public FormMainScreen(int pCount, string pName) { InitializeComponent(); ... } ... } The Dispose function for the sub form is modified so that, the 'close' and 'X' buttons actually hide the form so we dont have to re-create it every time. When the main screen closes, it sets a "flag" to 2, so the other forms know that it is actually ok to close; protected override void Dispose(bool disposing) { if (FormMainScreen.isExiting == 2) { if (disposing && (components != null)) { components.Dispose(); } base.Dispose(disposing); } else { if (xData.ActiveForm != null) { xData.ActiveForm.Hide(); } } } So, the question is, why would this work over and over and over again flawlessly, but, literally, about every 1/1000 of the time, cause an exception, or rather, why is my form being disposed? I had a suspicion that the garbage collector was getting confused, because it occurs slightly more frequently after it has been running for many hours.

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