Search Results

Search found 7666 results on 307 pages for 'pointer to member'.

Page 31/307 | < Previous Page | 27 28 29 30 31 32 33 34 35 36 37 38  | Next Page >

  • Google et Blink tournent le dos au W3C et à Pointer Events de Microsoft, au profit de Touch Events d'Apple ?

    Google et Blink tournent le dos au W3C et à Pointer Events de Microsoft au profit de Touch Events d'Apple ? Google et son moteur de rendu Web Blink ont finalement tranché en défaveur du standard du W3C, en effet à travers un bref communiqué sur la plateforme de développement de Blink, Google vient d'annoncer l'abandon de l'API Pointer Events, jusqu'ici présentée comme le futur standard du W3C en remplacement de Touch Events.Pour rappel Blink est le fork du célèbre moteur de rendu web Webkit actuellement...

    Read the article

  • how to cout a vector of structs (that's a class member, using extraction operator)

    - by Julz
    hi, i'm trying to simply cout the elements of a vector using an overloaded extraction operator. the vector contians Point, which is just a struct containing two doubles. the vector is a private member of a class called Polygon, so heres my Point.h #ifndef POINT_H #define POINT_H #include <iostream> #include <string> #include <sstream> struct Point { double x; double y; //constructor Point() { x = 0.0; y = 0.0; } friend std::istream& operator >>(std::istream& stream, Point &p) { stream >> std::ws; stream >> p.x; stream >> p.y; return stream; } friend std::ostream& operator << (std::ostream& stream, Point &p) { stream << p.x << p.y; return stream; } }; #endif my Polygon.h #ifndef POLYGON_H #define POLYGON_H #include "Segment.h" #include <vector> class Polygon { //insertion operator needs work friend std::istream & operator >> (std::istream &inStream, Polygon &vertStr); // extraction operator friend std::ostream & operator << (std::ostream &outStream, const Polygon &vertStr); public: //Constructor Polygon(const std::vector<Point> &theVerts); //Default Constructor Polygon(); //Copy Constructor Polygon(const Polygon &polyCopy); //Accessor/Modifier methods inline std::vector<Point> getVector() const {return vertices;} //Return number of Vector elements inline int sizeOfVect() const {return vertices.size();} //add Point elements to vector inline void setVertices(const Point &theVerts){vertices.push_back (theVerts);} private: std::vector<Point> vertices; }; and Polygon.cc using namespace std; #include "Polygon.h" // Constructor Polygon::Polygon(const vector<Point> &theVerts) { vertices = theVerts; } //Default Constructor Polygon::Polygon(){} istream & operator >> (istream &inStream, Polygon::Polygon &vertStr) { inStream >> ws; inStream >> vertStr; return inStream; } // extraction operator ostream & operator << (ostream &outStream, const Polygon::Polygon &vertStr) { outStream << vertStr.vertices << endl; return outStream; } i figure my Point insertion/extraction is right, i can insert and cout using it and i figure i should be able to just...... cout << myPoly[i] << endl; in my driver? (in a loop) or even... cout << myPoly[0] << endl; without a loop? i've tried all sorts of myPoly.at[i]; myPoly.vertices[i]; etc etc also tried all veriations in my extraction function outStream << vertStr.vertices[i] << endl; within loops, etc etc. when i just create a... vector<Point> myVect; in my driver i can just... cout << myVect.at(i) << endl; no problems. tried to find an answer for days, really lost and not through lack of trying!!! thanks in advance for any help. please excuse my lack of comments and formatting also there's bits and pieces missing but i really just need an answer to this problem thanks again

    Read the article

  • Reason for Null pointer Exception

    - by Rahul Varma
    Hi, I cant figure out why my program is showing null pointer exception. Plz help me...Here's the program... public class MusicListActivity extends Activity { List<HashMap<String, String>> songNodeDet = new ArrayList<HashMap<String,String>>(); HashMap<?,?>[] songNodeWeb; XMLRPCClient client; String logInSess; ArrayList<String> paths=new ArrayList<String>(); public ListAdapter adapter ; Object[] websongListObject; List<SongsList> SngList=new ArrayList<SongsList>(); Runnable r; ProgressDialog p; ListView lv; String s; @Override public void onCreate(Bundle si){ super.onCreate(si); setContentView(R.layout.openadiuofile); lv=(ListView)findViewById(R.id.list1); r=new Runnable(){ public void run(){ try{ getSongs(); } catch (MalformedURLException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (XMLRPCException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }; Thread t=new Thread(r,"background"); t.start(); Log.e("***","process over"); } @Override protected void onResume() { // TODO Auto-generated method stub super.onResume(); } private Runnable returnRes = new Runnable() { @Override public void run() { Log.d("handler","handler"); removeDialog(0); p.dismiss(); list(); } }; public void list() { Log.d("#####","#####"); LayoutInflater inflater=getLayoutInflater(); String[] from={}; int[] n={}; adapter=new SongsAdapter(getApplicationContext(),songNodeDet,R.layout.row,from,n,inflater); lv.setAdapter(adapter);} private Handler handler = new Handler() { public void handleMessage(Message msg){ Log.d("*****","handler"); removeDialog(0); p.dismiss(); } }; public void webObjectList(Object[] imgListObj,String logInSess) throws XMLRPCException{ songNodeWeb = new HashMap<?,?>[imgListObj.length]; if(imgListObj!=null){ Log.e("completed","completed"); for(int i=0;i<imgListObj.length;i++){ //imgListObj.length songNodeWeb[i]=(HashMap<?,?>)imgListObj[i]; String nodeid=(String) songNodeWeb[i].get("nid"); break; Log.e("img",i+"completed"); HashMap<String,String> nData=new HashMap<String,String>(); nData.put("nid",nodeid); Object nodeget=client.call("node.get",logInSess,nodeid); HashMap<?,?> imgNode=(HashMap<?,?>)nodeget; String titleName=(String) imgNode.get("titles"); String movieName=(String) imgNode.get("album"); String singerName=(String) imgNode.get("artist"); nData.put("titles", titleName); nData.put("album", movieName); nData.put("artist", singerName); Object[] imgObject=(Object[])imgNode.get("field_image"); HashMap<?,?>[] imgDetails=new HashMap<?,?>[imgObject.length]; imgDetails[0]=(HashMap<?, ?>)imgObject[0]; String path=(String) imgDetails[0].get("filepath"); if(path.contains(" ")){ path=path.replace(" ", "%20"); } String imgPath="http://www.gorinka.com/"+path; paths.add(imgPath); nData.put("path", imgPath); Log.e("my path",path); String mime=(String)imgDetails[0].get("filemime"); nData.put("mime", mime); SongsList songs=new SongsList(titleName,movieName,singerName,imgPath,imgPath); SngList.add(i,songs); songNodeDet.add(i,nData); } Log.e("paths values",paths.toString()); // return imgNodeDet; handler.sendEmptyMessage(0); } } public void getSongs() throws MalformedURLException, XMLRPCException { String ur="http://www.gorinka.com/?q=services/xmlrpc"; URL u=new URL(ur); client = new XMLRPCClient(u); //Connecting to the website HashMap<?, ?> siteConn =(HashMap<?, ?>) client.call("system.connect"); // Getting initial sessio id String initSess=(String)siteConn.get("sessid"); //Login to the site using session id HashMap<?, ?> logInConn =(HashMap<?, ?>) client.call("user.login",initSess,"prakash","stellentsoft2009"); //Getting Login sessid logInSess=(String)logInConn.get("sessid"); websongListObject =(Object[]) client.call("nodetype.get",logInSess,""); webObjectList(websongListObject,logInSess); Log.d("webObjectList","webObjectList"); runOnUiThread(returnRes); } } Here's the Adapter associated... public class SongsAdapter extends SimpleAdapter{ static List<HashMap<String,String>> songsList; Context context; LayoutInflater inflater; public SongsAdapter(Context context,List<HashMap<String,String>> imgListWeb,int layout,String[] from,int[] to,LayoutInflater inflater) { super(context,songsList,layout,from,to); this.songsList=songsList; this.context=context; this.inflater=inflater; // TODO Auto-generated constructor stub } @Override public View getView(int postition,View convertView,ViewGroup parent)throws java.lang.OutOfMemoryError{ try { View v = ((LayoutInflater) inflater).inflate(R.layout.row,null); ImageView images=(ImageView)v.findViewById(R.id.image); TextView tvTitle=(TextView)v.findViewById(R.id.text1); TextView tvAlbum=(TextView)v.findViewById(R.id.text2); TextView tvArtist=(TextView)v.findViewById(R.id.text3); HashMap<String,String> songsHash=songsList.get(postition); String path=songsHash.get("path"); String title=songsHash.get("title"); String album=songsHash.get("album"); String artist=songsHash.get("artist"); String imgPath=path; final ImageView imageView = (ImageView) v.findViewById(R.id.image); AsyncImageLoaderv asyncImageLoader=new AsyncImageLoaderv(); Bitmap cachedImage = asyncImageLoader.loadDrawable(imgPath, new AsyncImageLoaderv.ImageCallback() { public void imageLoaded(Bitmap imageDrawable, String imageUrl) { imageView.setImageBitmap(imageDrawable); } }); imageView.setImageBitmap(cachedImage); tvTitle.setText(title); tvAlbum.setText(album); tvArtist.setText(artist); return v; } catch(Exception e){ Log.e("error",e.toString()); } return null; } public static Bitmap loadImageFromUrl(String url) { InputStream inputStream;Bitmap b; try { inputStream = (InputStream) new URL(url).getContent(); BitmapFactory.Options bpo= new BitmapFactory.Options(); bpo.inSampleSize=2; b=BitmapFactory.decodeStream(inputStream, null,bpo ); return b; } catch (IOException e) { throw new RuntimeException(e); } } } Here is what logcat is showing... 04-23 16:02:02.211: ERROR/completed(1450): completed 04-23 16:02:02.211: ERROR/paths values(1450): [] 04-23 16:02:02.211: DEBUG/*****(1450): handler 04-23 16:02:02.211: DEBUG/AndroidRuntime(1450): Shutting down VM 04-23 16:02:02.211: WARN/dalvikvm(1450): threadid=3: thread exiting with uncaught exception (group=0x4001aa28) 04-23 16:02:02.222: ERROR/AndroidRuntime(1450): Uncaught handler: thread main exiting due to uncaught exception 04-23 16:02:02.241: DEBUG/webObjectList(1450): webObjectList 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): java.lang.NullPointerException 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at com.stellent.gorinka.MusicListActivity$2.handleMessage(MusicListActivity.java:81) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at android.os.Handler.dispatchMessage(Handler.java:99) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at android.os.Looper.loop(Looper.java:123) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at android.app.ActivityThread.main(ActivityThread.java:4203) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at java.lang.reflect.Method.invokeNative(Native Method) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at java.lang.reflect.Method.invoke(Method.java:521) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) 04-23 16:02:02.252: ERROR/AndroidRuntime(1450): at dalvik.system.NativeStart.main(Native Method) I have declared the getter and setter methods in a seperate claa named SongsList. Plz help me determine the problem...

    Read the article

  • Convert Decimal to ASCII

    - by Dan Snyder
    I'm having difficulty using reinterpret_cast. Before I show you my code I'll let you know what I'm trying to do. I'm trying to get a filename from a vector full of data being used by a MIPS I processor I designed. Basically what I do is compile a binary from a test program for my processor, dump all the hex's from the binary into a vector in my c++ program, convert all of those hex's to decimal integers and store them in a DataMemory vector which is the data memory unit for my processor. I also have instruction memory. So When my processor runs a SYSCALL instruction such as "Open File" my C++ operating system emulator receives a pointer to the beginning of the filename in my data memory. So keep in mind that data memory is full of ints, strings, globals, locals, all sorts of stuff. When I'm told where the filename starts I do the following: Convert the whole decimal integer element that is being pointed to to its ASCII character representation, and then search from left to right to see if the string terminates, if not then just load each character consecutively into a "filename" string. Do this until termination of the string in memory and then store filename in a table. My difficulty is generating filename from my memory. Here is an example of what I'm trying to do: C++ Syntax (Toggle Plain Text) 1.Index Vector NewVector ASCII filename 2.0 240faef0 128123792 'abc7' 'a' 3.0 240faef0 128123792 'abc7' 'ab' 4.0 240faef0 128123792 'abc7' 'abc' 5.0 240faef0 128123792 'abc7' 'abc7' 6.1 1234567a 243225 'k2s0' 'abc7k' 7.1 1234567a 243225 'k2s0' 'abc7k2' 8.1 1234567a 243225 'k2s0' 'abc7k2s' 9. //EXIT LOOP// 10.1 1234567a 243225 'k2s0' 'abc7k2s' Index Vector NewVector ASCII filename 0 240faef0 128123792 'abc7' 'a' 0 240faef0 128123792 'abc7' 'ab' 0 240faef0 128123792 'abc7' 'abc' 0 240faef0 128123792 'abc7' 'abc7' 1 1234567a 243225 'k2s0' 'abc7k' 1 1234567a 243225 'k2s0' 'abc7k2' 1 1234567a 243225 'k2s0' 'abc7k2s' //EXIT LOOP// 1 1234567a 243225 'k2s0' 'abc7k2s' Here is the code that I've written so far to get filename (I'm just applying this to element 1000 of my DataMemory vector to test functionality. 1000 is arbitrary.): C++ Syntax (Toggle Plain Text) 1.int i = 0; 2.int step = 1000;//top->a0; 3.string filename; 4.char *temp = reinterpret_cast<char*>( DataMemory[1000] );//convert to char 5.cout << "a0:" << top->a0 << endl;//pointer supplied 6.cout << "Data:" << DataMemory[top->a0] << endl;//my vector at pointed to location 7.cout << "Data(1000):" << DataMemory[1000] << endl;//the element I'm testing 8.cout << "Characters:" << &temp << endl;//my temporary char array 9. 10.while(&temp[i]!=0) 11.{ 12. filename+=temp[i];//add most recent non-terminated character to string 13. i++; 14. if(i==4)//when 4 chatacters have been added.. 15. { 16. i=0; 17. step+=1;//restart loop at the next element in DataMemory 18. temp = reinterpret_cast<char*>( DataMemory[step] ); 19. } 20. } 21. cout << "Filename:" << filename << endl; int i = 0; int step = 1000;//top-a0; string filename; char *temp = reinterpret_cast( DataMemory[1000] );//convert to char cout << "a0:" << top-a0 << endl;//pointer supplied cout << "Data:" << DataMemory[top-a0] << endl;//my vector at pointed to location cout << "Data(1000):" << DataMemory[1000] << endl;//the element I'm testing cout << "Characters:" << &temp << endl;//my temporary char array while(&temp[i]!=0) { filename+=temp[i];//add most recent non-terminated character to string i++; if(i==3)//when 4 chatacters have been added.. { i=0; step+=1;//restart loop at the next element in DataMemory temp = reinterpret_cast( DataMemory[step] ); } } cout << "Filename:" << filename << endl; So the issue is that when I do the conversion of my decimal element to a char array I assume that 8 hex #'s will give me 4 characters. Why isn't this this case? Here is my output: C++ Syntax (Toggle Plain Text) 1.a0:0 2.Data:0 3.Data(1000):4428576 4.Characters:0x7fff5fbff128 5.Segmentation fault

    Read the article

  • Hide cursor in Chrome (and IE)

    - by Chris
    I have the following CSS that hides the mouse cursor for anything on the web page. It works perfectly in FireFox but in IE and and Chrome it doesn't work. html { cursor: none; } In Chrome I always see the mouse pointer. In IE however I see whatever cursor was last 'active' when it entered the screen. Presumably it's keeping the last selection instead of removing it.

    Read the article

  • Seg Fault with malloc'd pointers

    - by anon
    I'm making a thread class to use as a wrapper for pthreads. I have a Queue class to use as a queue, but I'm having trouble with it. It seems to allocate and fill the queue struct fine, but when I try to get the data from it, it Seg. faults. http://pastebin.com/Bquqzxt0 (the printf's are for debugging, both throw seg faults) edit: the queue is stored in a dynamically allocated "struct queueset" array as a pointer to the data and an index for the data

    Read the article

  • Facing Null Pointer Exception while using BIRT

    - by srikanth
    Hi, I am using BIRT APIs in a java program.My code is : package com.tecnotree.mdx.product.utils; import java.util.HashMap; import java.util.logging.Level; import org.eclipse.birt.core.exception.BirtException; import org.eclipse.birt.core.framework.Platform; import org.eclipse.birt.report.engine.api.EngineConfig; import org.eclipse.birt.report.engine.api.EngineConstants; import org.eclipse.birt.report.engine.api.HTMLRenderOption; import org.eclipse.birt.report.engine.api.IReportEngine; import org.eclipse.birt.report.engine.api.IReportEngineFactory; import org.eclipse.birt.report.engine.api.IReportRunnable; import org.eclipse.birt.report.engine.api.IRunAndRenderTask; import org.eclipse.birt.report.engine.api.ReportEngine; public class ExampleReport { public static void main(String[] args) { // Variables used to control BIRT Engine instance ReportEngine eng = null; IReportRunnable design = null; IRunAndRenderTask task = null; HTMLRenderOption renderContext = null; HashMap contextMap = null; HTMLRenderOption options = null; final EngineConfig conf = new EngineConfig(); conf .setEngineHome("C:\\birt-runtime-2_5_2\\birt-runtime-2_5_2\\ReportEngine"); System.out.println("conf " + conf.getBIRTHome()); conf.setLogConfig(null, Level.FINE); try { Platform.startup(conf); } catch (BirtException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } IReportEngineFactory factory = (IReportEngineFactory) Platform .createFactoryObject(IReportEngineFactory.EXTENSION_REPORT_ENGINE_FACTORY); System.out.println("Factory : " + factory.toString()); System.out.println(conf.toString()); IReportEngine engine = factory.createReportEngine(conf); System.out.println("Engine : " + engine); try { design = eng .openReportDesign("C:\\birt-runtime-2_5_2\\birt-runtime-2_5_2\\ReportEngine\\samples\\hello_world.rptdesign"); } catch (Exception e) { System.err .println("An error occured during the opening of the report file!"); e.printStackTrace(); System.exit(-1); } task = eng.createRunAndRenderTask(design); renderContext = new HTMLRenderOption(); renderContext.setImageDirectory("image"); contextMap = new HashMap(); contextMap.put(EngineConstants.APPCONTEXT_HTML_RENDER_CONTEXT, renderContext); task.setAppContext(contextMap); options = new HTMLRenderOption(); options.setOutputFileName("c:/temp/output.html"); options.setOutputFormat("html"); task.setRenderOption(options); try { task.run(); } catch (Exception e) { System.err.println("An error occured while running the report!"); e.printStackTrace(); System.exit(-1); } System.out.println("All went well. Closing program!"); eng.destroy(); } } But i am facing NullPointerException while creating the report. STACKTRACE : Exception in thread "main" java.lang.NullPointerException at org.eclipse.birt.report.engine.api.impl.ReportEngine$EngineExtensionManager.<init>(ReportEngine.java:784) at org.eclipse.birt.report.engine.api.impl.ReportEngine.<init>(ReportEngine.java:109) at org.eclipse.birt.report.engine.api.impl.ReportEngineFactory$1.run(ReportEngineFactory.java:18) at org.eclipse.birt.report.engine.api.impl.ReportEngineFactory$1.run(ReportEngineFactory.java:1) at java.security.AccessController.doPrivileged(Native Method) at org.eclipse.birt.report.engine.api.impl.ReportEngineFactory.createReportEngine(ReportEngineFactory.java:14) at com.tecnotree.mdx.product.utils.ExampleReport.main(ExampleReport.java:47) Please help me regarding this... my project deadline has been reached... Appreciate your Reply Thanks in Advance

    Read the article

  • Exposing a pointer in Boost.Python

    - by Goose Bumper
    I have this very simple C++ class: class Tree { public: Node *head; }; BOOST_PYTHON_MODULE(myModule) { class_<Tree>("Tree") .def_readwrite("head",&Tree::head) ; } I want to access the head variable from Python, but the message I see is: No to_python (by-value) converter found for C++ type: Node* From what I understand, this happens because Python is freaking out because it has no concept of pointers. How can I access the head variable from Python? I understand I should use encapsulation, but I'm currently stuck with needing a non-encapsulation solution.

    Read the article

  • struct to bidimensional struct pointer assigment in C

    - by argos.void
    i want to get work this code and i googled and asked in efnet and freenode but i didnt find the answer. what i want i to assign a struct woot to an another bidimensional struct woot *, and i need malloc to do that. then, how can i use malloc there and how to assign the struct? thanks. #include <stdio.h> struct omg { int foo; }; struct woot { struct omg *localfoo; int foo; }; int a = sizeof(struct woot); int main(void){ struct woot *what[10][10] = (struct woot *) malloc(100*a); struct omg hahaha[100]; hahaha[1].foo = 15; what[1][6].localfoo = &hahaha[1]; }

    Read the article

  • Create a Generic IEnumerable<T> given a IEnumerable and the member datatypes

    - by ilias
    Hi, I get an IEnumerable which I know is a object array. I also know the datatype of the elements. Now I need to cast this to an IEnumerable<T, where T is a supplied type. For instance IEnumerable results = GetUsers(); IEnumerable<T> users = ConvertToTypedIEnumerable(results, typeof(User)); I now want to cast/ convert this to IEnumerable<User. Also, I want to be able to do this for any type. I cannot use IEnumerable.Cast<, because for that I have to know the type to cast it to at compile time, which I don't have. I get the type and the IEnumerable at runtime. - Thanks

    Read the article

  • JDBC Null pointer Exception thrown

    - by harigm
    Hi I'm getting nullpointerexception at rs.next() or rs.getString(1) it is really weird that sometimes rs.next() works fine and it throws nullpointerexception at rs.getString("PRODUCTCODE"),sometimes it throws npe at rs.getString("PRODDATE") i dont understand why rs.getString() thows npe while rs.next() works fine Here is my code { ResultSet rs = null; String query = ""; BarcodeBean bi = null; try { query = "SELECT * FROM TABLE(GET_BARCODEINFO('"barcode.trim()"'))"; statement = connection.createStatement(); Logger.getInstance().getLogger().logInfo(query); rs = statement.executeQuery(query); bi = new BarcodeBean(); if (rs == null){ if(rs.next()){ bi.setUrunKodu(rs.getString("PRODUCTCODE")); bi.setImalatMakineKodu(rs.getString("PRODMACHINECODE")); bi.setOperatorSicilNo(rs.getString("OPERATORID")); bi.setImalatTarihi(rs.getString("PRODDATE")); bi.setImalatVardiyasi(rs.getString("PRODSHIFT")); bi.setSeriNumarasi(rs.getString("SERIALNUMBER")); bi.setSirtTarihi(rs.getString("SIRTTARIHI")); } } } catch (SQLException e) { e.printStackTrace(); throw e; } catch (Exception e) { e.printStackTrace(); } finally { DatabaseUtility.close(rs); DatabaseUtility.close(statement); } }

    Read the article

  • (C#) iterate over read-only private collection member

    - by DGH
    I have a class which has two HashSet collections as private members. Other classes in my code would like to be able to iterate over those HashSets and read their contents. I don't want to write a standard getter because another class could still do something like myClass.getHashSet().Clear(); Is there any other way to expose the elements of my HashSets to iteration without exposing the reference to the HashSet itself? I'd love to be able to do this in a way that is compatible with for-each loops.

    Read the article

  • Non-member functions in Objective-C

    - by Jellyfingers McSlimedessert
    I want to write a standalone function in Objective-C; so essentially a C-style function, with Objective-C calls in it. For example: NSString* someFunc() { NSString* str = [[NSString alloc] init]; return str; } I declare the function in a header file, and define in it a .m file. However, the function doesn't appear to be compiled in, as the linker complains about the missing symbol. I thought that maybe I should put it in a C file, but then of course it spat at me for writing Objective-C Nonsense in BASI... C. What do?

    Read the article

  • ReadOnlyCollection or IEnumerable for exposing member collections?

    - by Erik Öjebo
    Is there any reason to expose an internal collection as a ReadOnlyCollection rather than an IEnumerable if the calling code only iterates over the collection? class Bar { private ICollection<Foo> foos; // Which one is to be preferred? public IEnumerable<Foo> Foos { ... } public ReadOnlyCollection<Foo> Foos { ... } } // Calling code: foreach (var f in bar.Foos) DoSomething(f); As I see it IEnumerable is a subset of the interface of ReadOnlyCollection and it does not allow the user to modify the collection. So if the IEnumberable interface is enough then that is the one to use. Is that a proper way of reasoning about it or am I missing something? Thanks /Erik

    Read the article

  • Help with malloc and free: Glibc detected: free(): invalid pointer

    - by nunos
    I need help with debugging this piece of code. I know the problem is in malloc and free but can't find exactly where, why and how to fix it. Please don't answer: "Use gdb" and that's it. I would use gdb to debug it, but I still don't know much about it and am still learning it, and would like to have, in the meanwhile, another solution. Thanks. #include <stdio.h> #include <stdlib.h> #include <ctype.h> #include <unistd.h> #include <string.h> #include <sys/wait.h> #include <sys/types.h> #define MAX_COMMAND_LENGTH 256 #define MAX_ARGS_NUMBER 128 #define MAX_HISTORY_NUMBER 100 #define PROMPT ">>> " int num_elems; typedef enum {false, true} bool; typedef struct { char **arg; char *infile; char *outfile; int background; } Command_Info; int parse_cmd(char *cmd_line, Command_Info *cmd_info) { char *arg; char *args[MAX_ARGS_NUMBER]; int i = 0; arg = strtok(cmd_line, " "); while (arg != NULL) { args[i] = arg; arg = strtok(NULL, " "); i++; } num_elems = i;precisa em free_mem if (num_elems == 0) return 0; cmd_info->arg = (char **) ( malloc(num_elems * sizeof(char *)) ); cmd_info->infile = NULL; cmd_info->outfile = NULL; cmd_info->background = 0; bool b_infile = false; bool b_outfile = false; int iarg = 0; for (i = 0; i < num_elems; i++) { if ( !strcmp(args[i], "<") ) { if ( b_infile || i == num_elems-1 || !strcmp(args[i+1], "<") || !strcmp(args[i+1], ">") || !strcmp(args[i+1], "&") ) return -1; i++; cmd_info->infile = malloc(strlen(args[i]) * sizeof(char)); strcpy(cmd_info->infile, args[i]); b_infile = true; } else if (!strcmp(args[i], ">")) { if ( b_outfile || i == num_elems-1 || !strcmp(args[i+1], ">") || !strcmp(args[i+1], "<") || !strcmp(args[i+1], "&") ) return -1; i++; cmd_info->outfile = malloc(strlen(args[i]) * sizeof(char)); strcpy(cmd_info->outfile, args[i]); b_outfile = true; } else if (!strcmp(args[i], "&")) { if ( i == 0 || i != num_elems-1 || cmd_info->background ) return -1; cmd_info->background = true; } else { cmd_info->arg[iarg] = malloc(strlen(args[i]) * sizeof(char)); strcpy(cmd_info->arg[iarg], args[i]); iarg++; } } cmd_info->arg[iarg] = NULL; return 0; } void print_cmd(Command_Info *cmd_info) { int i; for (i = 0; cmd_info->arg[i] != NULL; i++) printf("arg[%d]=\"%s\"\n", i, cmd_info->arg[i]); printf("arg[%d]=\"%s\"\n", i, cmd_info->arg[i]); printf("infile=\"%s\"\n", cmd_info->infile); printf("outfile=\"%s\"\n", cmd_info->outfile); printf("background=\"%d\"\n", cmd_info->background); } void get_cmd(char* str) { fgets(str, MAX_COMMAND_LENGTH, stdin); str[strlen(str)-1] = '\0'; } pid_t exec_simple(Command_Info *cmd_info) { pid_t pid = fork(); if (pid < 0) { perror("Fork Error"); return -1; } if (pid == 0) { if ( (execvp(cmd_info->arg[0], cmd_info->arg)) == -1) { perror(cmd_info->arg[0]); exit(1); } } return pid; } void type_prompt(void) { printf("%s", PROMPT); } void syntax_error(void) { printf("msh syntax error\n"); } void free_mem(Command_Info *cmd_info) { int i; for (i = 0; cmd_info->arg[i] != NULL; i++) free(cmd_info->arg[i]); free(cmd_info->arg); free(cmd_info->infile); free(cmd_info->outfile); } int main(int argc, char* argv[]) { char cmd_line[MAX_COMMAND_LENGTH]; Command_Info cmd_info; //char* history[MAX_HISTORY_NUMBER]; while (true) { type_prompt(); get_cmd(cmd_line); if ( parse_cmd(cmd_line, &cmd_info) == -1) { syntax_error(); continue; } if (!strcmp(cmd_line, "")) continue; if (!strcmp(cmd_info.arg[0], "exit")) exit(0); pid_t pid = exec_simple(&cmd_info); waitpid(pid, NULL, 0); free_mem(&cmd_info); } return 0; }

    Read the article

  • Return pointer to nested inner class from generic outer class

    - by helixed
    I'm new to C++, so bear with me. I have a generic class called A. A has a nested class called B. A contains a method called getB(), which is supposed to return a new instance of B. However, I can't get my code to compile. Here's what it looks like:#include A.h template <class E> class A { public: class B { public: int data; }; B * getB(); }; A.cpp #include "A.h" template <class E> A<E>::B * A::getB() { return new B(); } When I try to compile this, I get the following error: error: expected constructor, destructor, or type conversion before '*' token Does anybody know what I'm doing wrong? Thanks, helixed

    Read the article

  • Facebook events api: Event member (FQL)

    - by sunil-khedar
    I am fetching the event members for facebook events. Till yesterday I was getting the proper counts of members of an event. But suddenly the counts have following issues: For lot of plans on every consecutive request, I am getting random number of members. Strange issue. Seems facebook servers are not synced properly or something similar. Earlier for the same query string (mentioned below), I was getting the correct counts. But now the count is much less. It seems that at least for a few events now they are sending only the members who are connected with our application (we are using facebook connect). Example: for the following query currently I am getting "31" members. But on event page members count is much more. FQL: FB.Facebook.apiClient.fql_query('SELECT uid, eid, rsvp_status FROM event_member WHERE eid=336671213618', function(result, error){alert(result.length);}); Event page: http://www.facebook.com/event.php?eid=109411842404023 Is there any recent change in facebook API or policies? Thanks in advance.

    Read the article

  • Binding a member signal to a function

    - by the_drow
    This line of code compiles correctly without a problem: boost::bind(boost::ref(connected_), boost::dynamic_pointer_cast<session<version> >(shared_from_this()), boost::asio::placeholders::error); However when assigning it to a boost::function or as a callback like this: socket_->async_connect(connection_->remote_endpoint(), boost::bind(boost::ref(connected_), boost::dynamic_pointer_cast<session<version> >(shared_from_this()), boost::asio::placeholders::error)); I'm getting a whole bunch of incomprehensible errors (linked since it's too long to fit here). On the other hand I have succeeded binding a free signal to a boost::function like this: void print(const boost::system::error_code& error) { cout << "session connected"; } int main() { boost::signal<void(const boost::system::error_code &)> connected_; connected_.connect(boost::bind(&print, boost::asio::placeholders::error)); client<>::connection_t::socket_ptr socket_(new client<>::connection_t::socket_t(conn->service())); // shared_ptr of a tcp socket socket_->async_connect(conn->remote_endpoint(), boost::bind(boost::ref(connected_), boost::asio::placeholders::error)); conn->service().run(); // io_service.run() return 0; } This works and prints session connected correctly. What am I doing wrong here?

    Read the article

  • Objective-C Pointer to class that implements a protocol

    - by Winder
    I have three classes which implement the same protocol, and have the same parent class which doesn't implement the protocol. Normally I would have the protocol as pure virtual functions in the parent class but I couldn't find an Objective-C way to do that. How can I utilize polymorphism on these subclasses and call the functions implemented in the protocol without warnings? Some pseudocode if that didn't make sense: @interface superclass: NSObject {} @interface child1: superclass<MyProtocol> {} @interface child2: superclass<MyProtocol> {} The consumer of these classes: @class child1 @class child2 @class superclass @interface SomeViewController: UIViewController { child1 *oneView; child2 *otherView; superclass *currentView; } -(void) someMethod { [currentView protocolFunction]; } The only nice way I've found to do pure virtual functions in Objective-C is a hack by putting [self doesNotRecognizeSelector:_cmd]; in the parent class, but it isn't ideal.

    Read the article

  • Installing ImageMagick on Mac OSX 10.6

    - by Russell C.
    I just got a new Mac and am trying to setup a local Perl development environment. I'm using MAMP but also need the ImageMagick perl module installed in order to do some of the photo processing our scripts require. I tried installing ImageMagick manually but ran into some issues and after reading online a lot of people reported having issues going this route. The general consensus was to install it using MacPorts instead so I went ahead and installed MacPorts. Unfortunately, MacPorts can't seem to install it successfully either. Here is the command I'm using to try to install ImageMagick: sudo port install p5-perlmagick And here are all the errors reported during install: ---> Computing dependencies for p5-perlmagick ---> Building p5-perlmagick Error: Target org.macports.build returned: shell command " cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_perl_p5-perlmagick/work/PerlMagick-6.32" && /usr/bin/make -j2 all " returned error 2 Command output: Magick.xs:10918: error: 'struct Methods' has no member named 'exception' Magick.xs:10918: error: request for member 'severity' in something not a structure or union Magick.xs:10918: error: 'ErrorException' undeclared (first use in this function) Magick.xs:10919: error: 'struct Methods' has no member named 'exception' Magick.xs:10920: warning: implicit declaration of function 'GetImageException' Magick.xs:10922: error: 'struct PackageInfo' has no member named 'image_info' Magick.xs:10922: error: 'struct Methods' has no member named 'adjoin' Magick.xs:10929: error: request for member 'severity' in something not a structure or union Magick.xs:10929: error: 'UndefinedException' undeclared (first use in this function) Magick.xs:10929: error: request for member 'severity' in something not a structure or union Magick.xs:10929: error: request for member 'reason' in something not a structure or union Magick.xs:10929: error: request for member 'severity' in something not a structure or union Magick.xs:10929: error: request for member 'reason' in something not a structure or union Magick.xs:10929: warning: pointer/integer type mismatch in conditional expression Magick.xs:10929: error: request for member 'description' in something not a structure or union Magick.xs:10929: error: request for member 'description' in something not a structure or union Magick.xs:10929: error: request for member 'severity' in something not a structure or union Magick.xs:10929: error: request for member 'description' in something not a structure or union Magick.xs:10929: warning: pointer/integer type mismatch in conditional expression Magick.xs:10929: error: request for member 'description' in something not a structure or union Magick.xs:10929: warning: passing argument 2 of 'Perl_sv_catpv' from incompatible pointer type Magick.xs:10929: warning: unused variable 'message' Magick.xs:10856: warning: unused variable 'filename' Magick.c:10784: warning: unused variable 'ref' Magick.c:10777: warning: unused variable 'ix' Magick.xs: In function 'boot_Image__Magick': Magick.xs:2122: warning: implicit declaration of function 'InitializeMagick' Magick.xs:2123: warning: implicit declaration of function 'SetWarningHandler' Magick.xs:2124: warning: implicit declaration of function 'SetErrorHandler' make: *** [Magick.o] Error 1 Error: Status 1 encountered during processing. Before reporting a bug, first run the command again with the -d flag to get complete output. I have no idea what the problem might be or how to go about successfully installing ImageMagick. I'd appreciate any help & advice that someone out there that has done this successfully might be able to provide. Thanks in advance!

    Read the article

< Previous Page | 27 28 29 30 31 32 33 34 35 36 37 38  | Next Page >