objective c for c programmers

... acct[nacct].weightbal += acct[nacct].currbal * (daysinmo - acct[nacct].prevday); printf("Account %d: Opening %d, closing %d, avg %d\n", acct[acctx].ano, acct[acctx].openbal, acct[acctx].currbal, ... balance // Go through the accounts Close the month by adding // closing-balance values applicable to the final balance; // produce output record for(acctx = 0;acctx < nacct;++acctx) { acct[nacct].weightbal ... daysinmo, char * acctfn, char *jourfn) { FILE fid; int nacct, acctx; float acctno, openbal, xactnday, xactnamt struct { float ano; // account number float openbal; // opening balance float

Ngày tải lên: 18/03/2014, 00:20

... this code is not just a C program, but also a C++ program, since C++ derivedfrom C Because C++ has a high degree of source code compatibility with C, you can mix many C constructs with C++ constructs, ... aspects of your code The Visual C++ compiler can act as a normal C++ compiler or as a C++/CLI compiler By default, it remains a native compiler To use it as a C++/CLI com-piler, you use the compiler ... between C++ compilation and C++/CLI compilation—the result of native C++ compilation is native code, whereas the result of C++/CLI compilation is managed code If you try to compile the code on the command

Ngày tải lên: 12/08/2014, 16:21

... project reference automatically implies a project dependency The referencing project implicitly depends on the referenced project Therefore, the referenced project is built before the referencing ... its own string object containing the modified state On the other hand, creating new objects for each modification has its price Using String::Concatdirectly or indirectly to concatenate many strings ... functions, templates, variables, and so on C++ has introduced the concept of namespaces to avoid naming conflicts The CTS supports namespaces for the same reason C++/CLI allows you to manage CTS

Ngày tải lên: 12/08/2014, 16:21

... metadata table has a column structure specific for the abstraction The structures for all tables start with a 32-bit column called a metadata token Such a metadata token can be compared to a primary ... similar members exist Such runtime-bound dynamic access to type members is obviously much slower than a direct method call or direct field access (For static and non-static methods without ments ... typeobject for the serialized data can be requested Once the type object is available, a newinstance is created via Activator::CreateInstance To initialize each field, FieldInfo::SetValueis called for

Ngày tải lên: 12/08/2014, 16:21

... = t; // instance created via copy constructor This code implies that a default constructor and a copy constructor for T exist Withoutthese constructors, compiler errors would occur The last line ... type T are created, one with thedefault constructor and two with the copy constructor: T t; // instance created via default constructor T t1(t); // instance created via copy constructor T t2 ... discussion to Chapter 11 The CTS does not have a concept for destructors, but you can implement a special NETinterface to support a destructor-like deterministic resource cleanup This interface is calledSystem::IDisposable

Ngày tải lên: 12/08/2014, 16:21

... source files #pragma managed(push, off) Trang 11The first catch block in this code catches C++ exceptions of type int, and the second onecatches any CTS-compliant managed exceptions When a C++ ... used A performance object called NET CLR Memory provides various performance counters that are useful for this case Figure 7-4 shows how you can inspect statistics about NET garbage collection in ... the following code uses SEH exceptions, it can be compiled with /clr: // ExceptionHandling1.cpp // compile with "cl /clr ExceptionHandling1.cpp" #include <excpt.h> #include <windows.h>

Ngày tải lên: 12/08/2014, 16:21

... library can be a C or a C++ library This chapter gives you practical advice, general recommendations for all scenarios mentioned, and guidance for a couple of concrete problems Up-Front Considerations ... performance critical, you probably pre-fer convenience over performance C++/CLI interoperability already provides a lot of convenience—you only need normal function declarations to call a managed function ... with /clr, the output will be as follows: Direct call caused error code 0x57 Indirect call caused error code 0x0 If you face this problem in your code, you must move the indirect function call

Ngày tải lên: 12/08/2014, 16:21

... • Acquiring a CLR-specific object-based thread lock via Monitor.Enter or msclr::lock.Entering such a lock can result in a new lock structure being allocated • CAS checks • Calling NET objects ... feature that tries to forecast the lack of stack space so that a StackOverflowExceptionis thrown before you actually start executing critical code To achieve this, the code can be modified like ... exceptions can cause resource leaks The constructor of the wrapper class XYZConnection can cause a resource leak due to an asynchronous exception: XYZConnection() { xyzHandle.Handle = ::XYZConnect();

Ngày tải lên: 12/08/2014, 16:21

... or @public sections simil ar to C++. Objective-C doesn’t support multiple inheritance InstatwitViewController.h Trang 19you are here 4 95objective-c for the iPhone @property (nonatomic, retain) ... up, right? Objective-C can automatically release references, too. In addition to retain and release, Objective-C has the concept of an autorelease pool This is basically an array of objects that ... now! Back into Interface Builder to make the connection from the UIPickerView to the IBOutlet in our view controller Right-click on the UIPickerView, grab the circle next to the “New Referencing

Ngày tải lên: 14/08/2014, 20:21

... visible.Datasource Firecracker Lemon Drop Absolut Mixer Bee Stinger Cupid’s Mojito Miami Vice Captain e r c e C p a n The tablevi ew takes the new cell and scrolls it in As the user scrolls, some cells ... the scr een, it asks the datasource for a cell f or that row. The datasource check s the cell bucket to see if ther e are any cells available to reuse If so, i t just replaces the row’s contents ... your device What are Trang 11Table Cell Code Up Close// Customize the appearance of table view cells - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath cell = [[[UITableViewCell

Ngày tải lên: 14/08/2014, 20:21

... key value coding, which is a specific pattern typically used in Cocoa Binding The subtle catch is that NSDictionary usually just turns a call to valueForKey: into a call to objectForKey, and ... disclosure indicators: “The disclosure indicator element is necessary if you’re using the table to present hierarchical information.” DrinkMixer uses really basic cells, but you can easily customize ... information TableViewCells have a lot of built-in functionality—we’re just scratching the surface Adding a disclosure indicator is simply a matter of telling the cell what type of accessory icon it should

Ngày tải lên: 14/08/2014, 20:21

... NSNotification object Each notification comes with a notification object. Notification userInfo objects are dictionaries with notification-specific information in them. The notification object contains ... specific needs for your own, you can just use the default system-level one You can get a reference to the default one by calling: [[NSNotificationCenter defaultCenter]; With the notification center, ... UIScrollView can figure out everything else from there Content view Scroll View Elements (buttons, etc.) Remember, in CocoaTouch, components are subclasses of UIView All a scroll view needs to care

Ngày tải lên: 14/08/2014, 20:21

... are UITableViewController subclasses, and that the “With XIB for user interface” box is NOT checked. Create your two new classes for the Fugitive and Captured view controllers in Xcode, and then ... the Captured List FugitiveListViewController.h and m and CapturedListViewController.h and m both need to be subclasses of UITableViewController, so select “UIViewController subclass” and check ... The tab bar controller is another common iPhone interface Unlike the navigation controller, there isn’t really a stack All of the views are created up front and easily accessed by clicking the

Ngày tải lên: 14/08/2014, 20:21

... (iBountyHunterAppDelegate*)[[UIApplication sharedApplication] delegate]; NSManagedObjectContext *managedObjectContext = appDelegate. managedObjectContext; NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription ... Responsible for keeping track of managed objects active in the application All your fetch and save requests go through this Describes entities in your application including type information, data constraints, ... directories are by using the NSSearchPathForDirectoriesInDomains, just like the template does in the App Delegate: Library Preferences Caches tmp Trang 13Copy the database to the correct placeWhen

Ngày tải lên: 14/08/2014, 20:21

... ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) This code from iBountyHunterAppDelegate.m is checking for changes as you exit the app. The Managed Object Context ... This is the sort clause for a SQL command. Entity Info Sort Descriptor An NSFetchRequest describes the search we want Core Data to execute for us. Entity Information tells Core Data the type ... we’re searching for (and want back) For us, this is a Fugitive class. Here’s the piece we haven’t used before The predicate captures conditions the data must match If it doesn’t match, it doesn’t

Ngày tải lên: 14/08/2014, 20:21

... separate class conforming to the protocol that has a reference to its Fugitive (composition) rather than adding code to the Fugitive class directly. (CLLocationCoordinate2D) coordinate { CLLocationCoordinate2D ... intentionally or by accident) self.locationManager = [[CLLocationManager alloc] init]; self.locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters; self.locationManager.delegate = self; ... beats nothing Core Location actually decides which method to use based on what’s available to the device and what kind of accuracy you’re after That means none of that checking for source stuff;

Ngày tải lên: 14/08/2014, 20:21

... 2002 29 Using gcc  Two-stage compilation  pre-process & compile: gcc –c hello.c  link: gcc –o hello hello.o  Linking several modules: gcc –c a.c  a.o gcc –c b.c  b.o gcc –o hello a.o ... Using math library  gcc –o calc calc.c -lm Trang 30Oct 23, 2014 Advanced ProgrammingSpring 2002 30 Error reporting in gcc  Multiple sources  preprocessor: missing include files  parser: syntax ... referencing errors No output written to file. Trang 33Oct 23, 2014 Advanced ProgrammingSpring 2002 33 C preprocessor  The C preprocessor (cpp) is a processor which macro- manages a collection

Ngày tải lên: 23/10/2014, 13:56

... Using Public Access 102 Using Private Access 103 Using Protected Access 105 Using Class Variables 107 Accessing the Current Object 109 Creating a Variable for Multiple Object Types ... Functions 77 Chapter 5: Classes and Objects 79 Creating Objective-C Classes and Objects 82 Using Class Methods 84 Creating an Object 86 Creating Object Methods 87 Storing Data in Objects 88 ... shown here so Objective-C knows about the When the program ends, Objective-C will expect some indication of whether the func-tion succeeded We’ll return a value of 0 to Objective-C, which means there

Ngày tải lên: 29/03/2014, 06:20

... object-oriented capabilities to C language Runtime system (C library) Dynamic typing Dynamic binding GNU C compiler compiles C and Objective-C Apple donated Objective-C to GNU project (open source) ... Cocoa (Mac OS) and Cocoa touch (iPhone OS) Trang 21Core Services20 Core Foundation C Library Strings, dates, collections, threads, etc Address Book Framework Managing contact info CFNetwork C ... Objects, Inc All rights reserved worldwide.Layered Architecture C libraries and system calls Core Services (C libraries and Objective-C frameworks) Media Layer (C libraries and Objective-C frameworks)

Ngày tải lên: 21/07/2014, 23:36

... a new Objective- C source file is the ment block that Xcode generates for you: For inexplicable reasons, Xcode 3.1 does not include any user interface for changing the MyCompanyName placeholder ... So why, exactly, can’t we just use @class here? Because the compiler needs to know all about a superclass before it can successfully compile the @interface for its subclass The compiler needs ... the interface components: the @interface directive for the class, any public struct definitions, enumconstants, #defines, extern global variables, and so on Because of Objective- C’s C heri-tage,

Ngày tải lên: 12/08/2014, 20:22