Search Results

Search found 3592 results on 144 pages for 'this pointer'.

Page 96/144 | < Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >

• Android internet connectivity check problem

  - by Chaoz

  Hello, I'm new to Android development and working on an Android application that requires the phone to be connected to the internet, through either Wifi, EDGE or 3G. This is the code that I'm using: public static boolean isConnected() { ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); return cm.getActiveNetworkInfo().isConnectedOrConnecting(); } I've also set these permissions in the manifest file: <uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> This works fine in the emulator running version 1.5 of Android when 3G is enabled, but it crashes when I disable the 3G connection. My application throws a null pointer exception when I call isConnectedOrConnecting(). Hope that anyone knows the solution to this. Thanks in advance!

  Read the article

• Real thing about "->" and "."

  - by fsdfa

  I always wanted to know what is the real thing difference of how the compiler see a pointer to a struct (in C suppose) and a struct itself. struct person p; struct person *pp; pp->age, I always imagine that the compiler does: "value of pp + offset of atribute "age" in the struct". But what it does with person.p? It would be almost the same. For me "the programmer", p is not a memory address, its like "the structure itself", but of course this is not how the compiler deal with it. My guess is it's more of a syntactic thing, and the compiler always does (&p)->age. I'm correct?

  Read the article

• Why does accessing a member of a malloced array of structs seg fault?

  - by WSkinner

  I am working through Learn C The Hard Way and am stumped on something. I've written a simplified version of the problem I am running into to make it easier to get down to it. Here is the code: #include <stdlib.h> #define GROUP_SIZE 10 #define DATA_SIZE 64 struct Dummy { char *name; }; struct Group { struct Dummy **dummies; }; int main() { struct Group *group1 = malloc(sizeof(struct Group)); group1->dummies = malloc(sizeof(struct Dummy) * GROUP_SIZE); struct Dummy *dummy1 = group1->dummies[3]; // Why does this seg fault? dummy1->name = (char *) malloc(DATA_SIZE); return 0; } when I try to set the name pointer on one of my dummies I get a seg fault. Using valgrind it tells me this is uninitialized space. Why is this?

  Read the article

• Is there a leak in this copy code?

  - by Don Wilson

  Is there a leak in this code? // Move the group Group *movedGroup = [[Group alloc] init]; movedGroup = [[[[GroupList sharedGroupList] groups] objectAtIndex:fromIndex] copy]; [[GroupList sharedGroupList] deleteGroup:fromIndex]; [[GroupList sharedGroupList] insertGroup:movedGroup atIndex:toIndex]; // Update the loadedGroupIndex pointer if (loadedGroupIndex < fromIndex & loadedGroupIndex >= toIndex) { loadedGroupIndex = loadedGroupIndex + 1; } else if (loadedGroupIndex > fromIndex & loadedGroupIndex < toIndex) { loadedGroupIndex = loadedGroupIndex - 1; } else if (loadedGroupIndex == fromIndex) { loadedGroupIndex = toIndex; } [movedGroup release]

  Read the article

• Maven Quick-start Guide

  - by Dave

  I'm tasked with getting a development environment set up for a new program at work. The lead has chosen Eclipse as the IDE for its OSGi support and Maven as the build utility. I've struggled through getting Maven integrated with Eclipse and I'm grudgingly declaring success and moving forward. My question: is there any sort of guide to getting started with Maven? I've found boatloads of documentation, most all of it very, very detailed and simultaneously unhelpful. I downloaded a 300+ page book that goes into excruciating detail about POMs, but doesn't tell you how to initialize a project from existing source. Hopefully, this question will result in a pointer to something I missed or a collection of links for those who follow me.

  Read the article

• Best way to insert items from a Derived class's constructor into a Base class's private std::vector?

  - by Will

  I have these classes: class Base { ... private: std::vector<X> v; }; class Derived { Derived(X*, int n); } where the constructor of Derived is passed an array of item Xs, which I need to insert into my vector v in the Base class. (X is a smart pointer) Currently I see two ways to do this: 1) Create a function in Base: InsertItem(X*) that will insert an item into the vector. 2) Create a vector in Derived that contains the full list, then get it into Base by moving the entire vector. I dont see any advantages to #2, but was wondering if #1 was a good solution, or if there are better ways to do this. Thanks!

  Read the article

• Array of char *

  - by user353060

  Hello, I am having problems with array pointers. I've looked through Google and my attempts are futile so far. What I would like to do is, I have a char name[256]. I will be 10 of those. Hence, I would need to keep track of each of them by pointers. Trying to create a pointer to them. int main() { char superman[256] = "superman"; char batman[256] = "batman"; char catman[256] = "catman"; char *names[10]; names[0] = superman; names[1] = batman; system("pause"); return 0; } How do I actually traverse an array of pointers?

  Read the article

• Handle/Grip bar convention

  - by tomdemuyt

  Greetings, Because textarea elements do not resize with jquery.touch ( http://plugins.jquery.com/project/touch ), I've put an textarea in a table where the first row allows the user to drag the table around and resize it with the textarea growing/shrinking/moving along. It works well, except that users dont seem to 'get' that they can use the bar to resize/move. I was trying to find some 'grip bar' graphics but google isnt helping me. What is the best way to show users that an element can be moved/resized ? Pointer to graphics ( generators ) would be great. Or, does any one know how to make textarea's movable/resizable ? T.

  Read the article

• How to append text to a text file in WinAPI?

  - by Bruce

  Hi guys, Ive got an annoying problem, I cant append any text to the text file. Every time I open it for writing, I overwrite the data. I tried to move the file pointer to the end of the file, but no result (no writing to the file at all). Here is the code: INVOKE CreateFile, offset filePath, GENERIC_WRITE, FILE_SHARE_WRITE, 0, OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,0 mov hFile, eax mov edx, 10 INVOKE SetFilePointer, hFile, 0, 0, FILE_END INVOKE WriteFile, hFile, offset buffer, edx, ADDR SizeReadWrite, NULL INVOKE CloseHandle, hFile Any ideas? Thank you in advance!

  Read the article

• Double indirection and structures passed into a function

  - by ZPS

  I am curious why this code works: typedef struct test_struct { int id; } test_struct; void test_func(test_struct ** my_struct) { test_struct my_test_struct; my_test_struct.id=267; *my_struct = &my_test_struct; } int main () { test_struct * main_struct; test_func(&main_struct); printf("%d\n",main_struct->id); } This works, but pointing to the memory address of a functions local variable is a big no-no, right? But if i used a structure pointer and malloc, that would be the correct way, right? void test_func(test_struct ** my_struct) { test_struct *my_test_struct; my_test_struct = malloc(sizeof(test_struct)); my_test_struct->id=267; *my_struct = my_test_struct; } int main () { test_struct * main_struct; test_func(&main_struct); printf("%d\n",main_struct->id); }

  Read the article

• status failed for LdrLoadDll

  - by kiddo

  hello all,I'am trying to work-out the LdrLoadDll function and am having no luck with that..i also googled for some examples there is no much documentation or correct example about this.I know what it exactly does..Please check the code below. //declaration function pointer for LdrLoadDll typedef NTSTATUS (_stdcall*fp_LdrLoadDll)( IN PWCHAR PathToFile OPTIONAL, IN ULONG Flags OPTIONAL, IN PUNICODE_STRING ModuleFileName, OUT PHANDLE ModuleHandle ); //calling LdrLoadDll using getprocaddress HANDLE handle; HMODULE module = LoadLibrary(L"ntdll.dll"); fp_LdrLoadDll loadDll; loadDll = (fp_LdrLoadDll)GetProcAddress(module,"LdrLoadDll"); if(loadDll == NULL) { MessageBox(0,L"Not able to load the function",L"LdrLoadDll",&handle); } UNICODE_STRING input; input.Buffer = L"C:\\Desktop\\myDll.dll"; input.Length = wcslen(input.Buffer)*2; input.MaximumLength = wcslen(input.Buffer) +2; NTSTATUS status = loadDll(NULL,LOAD_WITH_ALTERED_SEARCH_PATH,&input,0); When i execute the above am not getting the handle niether valid status.Please help me with this.

  Read the article

• If free() knows the length of my array, why can't I ask for it in my own code?

  - by Chris Cooper

  I know that it's a common convention to pass the length of dynamically allocated arrays to functions that manipulate them: void initializeAndFree(int* anArray, int length); int main(){ int arrayLength = 0; scanf("%d", &arrayLength); int* myArray = (int*)malloc(sizeof(int)*arrayLength); initializeAndFree(myArray, arrayLength); } void initializeAndFree(int* anArray, int length){ int i = 0; for (i = 0; i < length; i++) { anArray[i] = 0; } free(anArray); } but if there's no way for me to get the length of the allocated memory from a pointer, how does free() "automagically" know what to deallocate? Why can't I get in on the magic, as a C programmer? Where does free() get its free (har-har) knowledge from?

  Read the article

• Drupal: Programmatically saving imagefield images

  - by Ace

  Hey there! I'm trying to write a sync function that saves some data to nodes, which works fine, until I try to save the thumbnail image associated with the node. I've managed to download the file and put it in my sites/default/files folder, but what's the best way to tell Drupal, "put this file in that CCK imagefield"? EDIT To clarify a bit.. I sync the thumbnails separately (since one image can be used by several nodes)... I would like the initial thumbnail sync to save the files in the correct folder (not a temp one) and just point the imagefield to this file... That's what annoys me with field_file_save_file(), it saves a new file instead of just making a pointer.. Any advice?

  Read the article

• What's void *userData exactly?

  - by mystify

  In a C function declaration, I have seen this parameter definition: void *userData so, what exactly is that? My guess: the void says it can be anything arbitrary, or even nothing. Almost similar to id of objective-c. It just allows to pass in whatever data structure you like. The star in front of userData says, that the argument must be passed in by reference. So when using this stuff in the function body, typically it must be casted and dereferenced. So if I pass in an pointer to SomeClass instance, I would get that like this: SomeClass *myObj = (SomeClass*)userData; In the case I had nothing special to pass along, I would provide NULL as argument. Are my assumptions correct? Or did I get something wrong?

  Read the article

• Objective-C: Initializing char with char at index of string.

  - by Mr. McPepperNuts

  unichar myChar = [myString characterAtIndex:0]; [myNSMutableArray addObject:myChar]; I am trying to insert the first char of a string into an array, to create an array of chars. the first line does not give me an error. The second line however, provides the following error: warning: passing argument 1 of 'addObject:' makes pointer from integer without a cast This also crashes the application with a "bad address" error. I thought this error was due to a problem with memory allocation. Can someone shed some light on this.

  Read the article

• Compatible types and structures in C

  - by Oli Charlesworth

  I have the following code: int main(void) { struct { int x; } a, b; struct { int x; } c; struct { int x; } *p; b = a; /* OK */ c = a; /* Doesn't work */ p = &a; /* Doesn't work */ return 0; } which fails to compile under GCC (3.4.6), with the following error: test.c:8: error: incompatible types in assignment test.c:9: warning: assignment from incompatible pointer type Now, from what I understand (admittedly from the C99 standard), is that a and c should be compatible types, as they fulfill all the criteria in section 6.2.7, paragraph 1. I've tried compiling with std=c99, to no avail. Presumably my interpretation of the standard is wrong?

  Read the article

• C optimization breaks algorithm

  - by Halpo

  I am programming an algorithm that contains 4 nested for loops. The problem is at at each level a pointer is updated. The innermost loop only uses 1 of the pointers. The algorithm does a complicated count. When I include a debugging statement that logs the combination of the indexes and the results of the count I get the correct answer. When the debugging statement is omitted, the count is incorrect. The program is compiled with the -O3 option on gcc. Why would this happen?

  Read the article

• Objective C LValue required as unary '&' operand

  - by Bob

  Hello! In my code, I get this error when I try to get a pointer to my class property. (I wrote a small *.OBJ file translator in Python, discarding the normals) CODE: //line: line of text const char *str = [line UTF8String]; Point3D *p1, *p2, *p3; p1 = [Point3D makeX:0 Y:0 Z:0]; p2 = [Point3D makeX:0 Y:0 Z:0]; p3 = [Point3D makeX:0 Y:0 Z:0]; sscanf(str, "t %f,%f,%f %f,%f,%f %f,%f,%f",(&[p1 x]),&([p1 y]),&([p1 z]),&([p2 x]),&([p2 y]),&([p2 z]),&([p3 x]),&([p3 y]),&([p3 z])); Triangle3D *tri = [Triangle3D make:p1 p2:p2 p3:p3];

  Read the article

• Writing a PHP web crawler using cron

  - by Horse

  Hi all I have written myself a web crawler using simplehtmldom, and have got the crawl process working quite nicely. It crawls the start page, adds all links into a database table, sets a session pointer, and meta refreshes the page to carry onto the next page. That keeps going until it runs out of links That works fine however obviously the crawl time for larger websites is pretty tedious. I wanted to be able to speed things up a bit though, and possibly make it a cron job. Any ideas on making it as quick and efficient as possible other than setting the memory limit / execution time higher?

  Read the article

• QList as a function parameter - Linking Error - LNK2019

  - by user2445136

  I have an issue with QList as a function parameter and I'll be glad if you can assist me. I have this code for example: void SpinBoxList_Enable(QList spinBoxList) { foreach(QWidget mWidget,*spinBoxList) mWidget-setEnabled(false); } and in the implemantation file I use the QList variable as a pointer: SpinBoxList_Enable(&controlBoardSpinBoxList); ( controlBoardSpinBoxList is a variable of QList ). The Function ToggleBoards_Slot(bool) is a slot that uses When I compile, I get this error message: 1cmosaixserialnumber.obj : error LNK2019: unresolved external symbol "private: void __cdecl CMosaixSerialNumber::SpinBoxList_Disable(class QList *)" (?SpinBoxList_Disable@CMosaixSerialNumber@@AEAAXPEAV?$QList@PEAVQWidget@@@@@Z) referenced in function "public: void __cdecl CMosaixSerialNumber::ToggleBoards_Slot(bool)" (?ToggleBoards_Slot@CMosaixSerialNumber@@QEAAX_N@Z) 1cmosaixserialnumber.obj : error LNK2019: unresolved external symbol "private: void __cdecl CMosaixSerialNumber::SpinBoxList_Enable(class QList *)" (?SpinBoxList_Enable@CMosaixSerialNumber@@AEAAXPEAV?$QList@PEAVQWidget@@@@@Z) referenced in function "private: void __cdecl CMosaixSerialNumber::on_ControlBoardCheckBox_StateChanged(int)" (?on_ControlBoardCheckBox_StateChanged@CMosaixSerialNumber@@AEAAXH@Z) How can I fix this ? Thanks, EVH671

  Read the article

• What is XcvPort (used in OpenPrinter function)

  - by RiskX

  I'm usin the OpenPrinter function and the first parameter the function gets called "pPrinterName" and that's it's MSDN description: [in] Pointer to a null-terminated string that specifies the name of the printer or print server, the printer object, the XcvMonitor, or the XcvPort. For a printer object use: PrinterName,Job xxxx. For an XcvMonitor, use: ServerName,XcvMonitor MonitorName. For an XcvPort, use: ServerName,XcvPort PortName. Obviously I'm interested in the bold part. What exactly is XcvPort? I know it seems like a question of lazy person but I really couldn't find info abou this concept. If I would like to open a printer on port ABC I should write: "\\MySrever,XcvPort ABC"? Thank you for your answers!

  Read the article

• Why does a delegate with no parameters compile?

  - by Ryan

  I'm confused why this compiles: private delegate int MyDelegate(int p1, int p2); private void testDelegate() { MyDelegate imp = delegate { return 1; }; } MyDelegate should be a pointer to a method that takes two int parameters and returns another int, right? Why am I allowed to assign a method that takes no parameters? Interestingly, these doesn't compile (it complains about the signature mismatches, as I'd expect) private void testDelegate() { // Missing param MyDelegate imp = delegate(int p1) { return 1; }; // Wrong return type MyDelegate imp2 = delegate(int p1, int p2) { return "String"; }; } Thanks for any help! Ryan

  Read the article

• c++/cli pass (managed) delegate to unmanaged code

  - by Ron Klein

  How do I pass a function pointer from managed C++ (C++/CLI) to an unmanaged method? I read a few articles, like this one from MSDN, but it describes two different assemblies, while I want only one. Here is my code: 1) Header (MyInterop.ManagedCppLib.h): #pragma once using namespace System; namespace MyInterop { namespace ManagedCppLib { public ref class MyManagedClass { public: void DoSomething(); }; }} 2) CPP Code (MyInterop.ManagedCppLib.cpp) #include "stdafx.h" #include "MyInterop.ManagedCppLib.h" #pragma unmanaged void UnmanagedMethod(int a, int b, void (*sum)(const int)) { int result = a + b; sum(result); } #pragma managed void MyInterop::ManagedCppLib::MyManagedClass::DoSomething() { System::Console::WriteLine("hello from managed C++"); UnmanagedMethod(3, 7, /* ANY IDEA??? */); } I tried creating my managed delegate and then I tried to use Marshal::GetFunctionPointerForDelegate method, but I couldn't compile.

  Read the article

• jQuery click event not working when mouse moves from one div to another with button held down

  - by Acorn

  I've made a page that uses jQuery to allow you to place <div>s on the page based on your mouse coordinates when you click. The page And here's the javascript: $('document').ready(function() { $("#canvas").click(function(e){ var x = e.pageX - this.offsetLeft; var y = e.pageY - this.offsetTop; $(document.createElement('div')).css({'left':x + 'px', 'top':y + 'px'}).addClass('tile').appendTo('#canvas'); }); }); I've found that if you mousedown in the div#canvas and mouseup with your pointer over a placed <div> (or vice versa) then a new <div> doesn't get placed. Why is this?

  Read the article

• OpenGL texture not showing up on some computers, problem with auxDIBImageLoad?

  - by CptanPanic

  I have a simple openGL GUI that has uses a bmp as a texture. The problem is on some computers the texture doesn't show up. But on ones with newer OpenGL drivers it works. How can I make it more compatible. I think the problem may be with auxDIBImageLoad. When I inspect the result, I see the x,y correct, but the data pointer points to memory bank with all zeros. What could be wrong?

  Read the article

< Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >