CodeProject Latest postings for Objective-C and Swift

Looking for suggestions, and clarify a few things for a beginning Apple programmer

jkirkerx — Thu, 04 Jan 2024 22:51:00 GMT

I recently bought a Mac Mini, loaded up XCode and created my first app, the demo iPhone app and ran it on my Virtual iPhone on the Mac, so that part works now.

I have a couple of questions about Xcode and this project I created, that wasn't too clear to me on some YouTube videos. I sort of get what Objective C is, but not to clear on it. And I sort of get what Swift is, but not clear on it.

Is Objective C the base language? I was looking at the sample code generated and it looks like some sort of controller view system, sort of like Microsoft MVC. Or are libraries already created in Objective C and I use Swift to write simple code to execute logic and generate it to the a assigned view or screen, where the underlying Objective C code executes it.

I was just book shopping on Amazon and the web, and so many books are published on the subject, some promoting Objective C and others promoting Swift, so I'm not sure what book to buy.

My goal is to write a robust iPhone app that collects data and stores it in the cloud or on the device like where, when and notes, and then a larger app like on a iPad or Mac can analyze the data and help find fixes for the user. It's a sports app to help players be better.

I need to move fast on this and would appreciate your experience and thoughts. Or any books that I can read to catch up on this technology. I was going to React Native, but was told to just build the app with native tools by Apple.

If it ain't broke don't fix it
Discover my world at jkirkerx.com

How can I decipher, or understand what I reading in an M4A file?

SergioQ — Tue, 25 Jan 2022 02:52:00 GMT

I have my Swift app that records audio in chunks of multiple files, each M4A file is approx 1 minute long. I would like to go through those files and detect silence, or the lowest level
.
While I am able to read the file into a buffer, my problem is deciphering it. Even with Google, all it comes up with is "audio players" instead of sites that describe the header and the data.

Where can I find what to look for? Or even if I should be reading it into a WAV file? But even then I cannot seem to find a tool, or a site, that tells me how to decipher what I am reading.

Obviously it exists, since Siri knows when you've stopped speaking. Just trying to find the key.

How can I take data from PDF form to Excel on specified cells

Member 14643603 — Mon, 04 Nov 2019 09:18:00 GMT

Hi,

Is it possible to create code that works on MAC and Windows too (My concern is about MAC but if both platforms that would be great) to get data from predefined PDF form fields into predefined excel template?

If yes can you please provide simple exams of code to test?

How to get Idle time of mac?

UJ7 — Sat, 28 Jul 2018 09:57:00 GMT

I need to code in swift that can calculate the idle time of system.

How to design game

HerryF — Sat, 19 May 2018 11:22:00 GMT

i don't know to create video in Game screen

Recently i decided to learn swift again[Help]

HerryF — Tue, 09 Oct 2018 06:15:00 GMT

Frist of all i need more example / case study during learing swift.

NSPrintOperation graphic context affect my custom print view?

Le@rner — Mon, 05 Feb 2018 05:04:00 GMT

hi all,

i m using NSPrintOperation using view.

NSPrintOperation graphic context affect my print view design.

when i print in landscape page my design also rotate.

please help me how can i handle this.

thanks in advance.

NSPrintOperation not print properly Landscape print

Le@rner — Wed, 31 Jan 2018 07:13:00 GMT

HI all

i am using NSPrintOperation with NSView for printing.

portrait pages are print well,

but Landscape printing not done properly please help me for this.

NSPrintOperation* printOperation = [NSPrintOperation printOperationWithView:my_print_view printInfo:printInfo];
        
        [[printOperation printInfo] setPaperSize:printInfo.paperSize];
        
        [[printOperation printInfo] setOrientation:NSPaperOrientationLandscape];
        
        
        [printOperation setCanSpawnSeparateThread:YES];
        [printOperation setShowsPrintPanel:NO];
               
        [printOperation runOperationModalForWindow:window delegate:window didRunSelector:nil contextInfo:nil]

thanks in advance.

my application crashed with this message NSInternalInconsistencyException', reason: 'Printing failed because PMSessionEndDocumentNoDialog() returned -30871.'

Le@rner — Wed, 17 Jan 2018 11:50:00 GMT

hi all

on printing action application get crashed with NSInternalInconsistencyException', reason: 'Printing failed because PMSessionEndDocumentNoDialog() returned -30871.' message.

please help me for this.

crash log is

Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Crashed Thread:  4

Application Specific Information:
abort() called
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Printing failed because PMSessionEndDocumentNoDialog() returned -30871.'
*** Call stack at first throw:
(
	0   CoreFoundation                      0x00007fff83ab3784 __exceptionPreprocess + 180
	1   libobjc.A.dylib                     0x00007fff89814f03 objc_exception_throw + 45
	2   CoreFoundation                      0x00007fff83ab35a7 +[NSException raise:format:arguments:] + 103
	3   CoreFoundation                      0x00007fff83ab3534 +[NSException raise:format:] + 148
	4   AppKit                              0x00007fff879c386e -[NSPrintSpoolingGraphicsContext dealloc] + 37
	5   CoreFoundation                      0x00007fff83a2ff93 __CFArrayReleaseValues + 435
	6   CoreFoundation                      0x00007fff83a0da73 _CFRelease + 179
	7   AppKit                              0x00007fff8746e53d __NSAppKitFinalizeThreadData + 260
	8   libSystem.B.dylib                   0x00007fff8098f751 _pthread_tsd_cleanup + 187
	9   libSystem.B.dylib                   0x00007fff8098f39c _pthread_exit + 147
	10  Foundation                          0x00007fff84f9718f __NSFinalizeThreadData + 0
	11  Foundation                          0x00007fff84f97127 __NSThread__main__ + 1448
	12  libSystem.B.dylib                   0x00007fff8098efd6 _pthread_start + 331
	13  libSystem.B.dylib                   0x00007fff8098ee89 thread_start + 13
)

Thread 4 Crashed:
0   libSystem.B.dylib             	0x00007fff809c89ce __semwait_signal_nocancel + 10
1   libSystem.B.dylib             	0x00007fff809c88d0 nanosleep$NOCANCEL + 129
2   libSystem.B.dylib             	0x00007fff80a253ce usleep$NOCANCEL + 57
3   libSystem.B.dylib             	0x00007fff80a44a00 abort + 93
4   libstdc++.6.dylib             	0x00007fff8a10e5d2 __tcf_0 + 0
5   libobjc.A.dylib               	0x00007fff89818b39 _objc_terminate + 100
6   libstdc++.6.dylib             	0x00007fff8a10cae1 __cxxabiv1::__terminate(void (*)()) + 11
7   libstdc++.6.dylib             	0x00007fff8a10cb16 __cxxabiv1::__unexpected(void (*)()) + 0
8   libstdc++.6.dylib             	0x00007fff8a10cbfc __gxx_exception_cleanup(_Unwind_Reason_Code, _Unwind_Exception*) + 0
9   libobjc.A.dylib               	0x00007fff89814fa2 object_getIvar + 0
10  com.apple.CoreFoundation      	0x00007fff83ab35a7 +[NSException raise:format:arguments:] + 103
11  com.apple.CoreFoundation      	0x00007fff83ab3534 +[NSException raise:format:] + 148
12  com.apple.AppKit              	0x00007fff879c386e -[NSPrintSpoolingGraphicsContext dealloc] + 37
13  com.apple.CoreFoundation      	0x00007fff83a2ff93 __CFArrayReleaseValues + 435
14  com.apple.CoreFoundation      	0x00007fff83a0da73 _CFRelease + 179
15  com.apple.AppKit              	0x00007fff8746e53d __NSAppKitFinalizeThreadData + 260
16  libSystem.B.dylib             	0x00007fff8098f751 _pthread_tsd_cleanup + 187
17  libSystem.B.dylib             	0x00007fff8098f39c _pthread_exit + 147
18  com.apple.Foundation          	0x00007fff84f9718f __NSFinalizeThreadData + 0
19  com.apple.Foundation          	0x00007fff84f97127 __NSThread__main__ + 1448
20  libSystem.B.dylib             	0x00007fff8098efd6 _pthread_start + 331
21  libSystem.B.dylib             	0x00007fff8098ee89 thread_start + 13

NSImage become blurry after transfromation

Le@rner — Sat, 08 Jul 2017 06:27:00 GMT

i rotate an image using this

- (NSImage*)imageRotatedByDegrees_Angle:(CGFloat)degrees
{
    [[NSGraphicsContext
      currentContext] setImageInterpolation: NSImageInterpolationNone];
    
    // Calculate the bounds for the rotated image
    // We do this by affine-transforming the bounds rectangle
    NSRect imageBounds = {NSZeroPoint, [self size]};
    NSBezierPath* boundsPath = [NSBezierPath bezierPathWithRect:imageBounds];
    NSAffineTransform* transform = [NSAffineTransform transform];
    [transform rotateByDegrees:-1.0 * degrees];// we want clockwise angles
    [boundsPath transformUsingAffineTransform:transform];
    NSRect rotatedBounds = {NSZeroPoint, [boundsPath bounds].size};
    
    // Center the image within the rotated bounds
    imageBounds.origin.x = NSMidX(rotatedBounds) - (NSWidth(imageBounds) / 2);
    imageBounds.origin.y = NSMidY(rotatedBounds) - (NSHeight(imageBounds) / 2);
    
    NSImage* rotatedImage = [[NSImage alloc] initWithSize:rotatedBounds.size];
    //NSSize new_size=[self size];
    

            NSAffineTransform* transform1 = [NSAffineTransform transform];
       
            [transform1 translateXBy:+(NSWidth(rotatedBounds) / 2)
                                yBy:+(NSHeight(rotatedBounds) / 2)];
            // Do the rotation
            [transform1 rotateByDegrees:-1.0 * degrees];
            

            [transform1 translateXBy:-(NSWidth(rotatedBounds) / 2)
                                yBy:-(NSHeight(rotatedBounds) / 2)];
        
        

         [NSGraphicsContext saveGraphicsState];
     
        
        [[NSGraphicsContext currentContext]
         setImageInterpolation:NSImageInterpolationHigh];
        
        
        [rotatedImage lockFocus];
        
        
            [transform1 concat];
        
            [self drawInRect: imageBounds fromRect:NSZeroRect operation:NSCompositeCopy fraction:1.0];
        
        
         [rotatedImage unlockFocus];
        
        [NSGraphicsContext restoreGraphicsState];
        
            
    return rotatedImage;
    
}

image is rotated but the rotated image is so blurry.

Does anyone know how to solve it?

please help me for this.

NSMutableArray copy problem

Le@rner — Tue, 27 Jun 2017 07:19:00 GMT

Hi all,

i have two different NSMutableArray one is source array and other is backup array,

on some action copy the source array value to backup array.

than continue the changes in source array objects.

but here the backup array objects value automatically changed as i changed in source array.

please help me i don't want to change backup array object even i change in source array object.

thanks in advance.

How to access webcam and capture image?

Le@rner — Wed, 07 Jun 2017 09:36:00 GMT

hi all,

please guide me to how to access connected webcam in my machine and capture the image from camera.

thanks in advance.

how add control manually in NSBox?

Le@rner — Tue, 16 May 2017 06:36:00 GMT

Hi all,

i want to add textfield and checkbox in a box.

i use size to fit option for fox after adding control, its resize the box but change the location of box upward .

i don't want to change the location of box,

i want when i add control box increase height at downward.

please help me for this.

Can i use scanline Flood Fill algorithm to apply gradient in UIImage?How to use?

Member 13195612 — Fri, 12 May 2017 07:09:00 GMT

Need help

Crashing in printing

Le@rner — Wed, 05 Apr 2017 11:22:00 GMT

hi all,

when i trying to print or preview multiple pages from my application

i got this

exception

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Printing failed because PMSessionEndDocumentNoDialog() returned -30871.'

i really don't understand

what can i do here.

in printing i pass an image creating from rendering of my customise view.

please help me for this.

if there is a one page its working fine

but when i create different image at time of printing its crash

crash log:

Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Crashed Thread:  7

Application Specific Information:
abort() called
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Printing failed because PMSessionEndDocumentNoDialog() returned -30871.'

Thread 7 Crashed:
0   libSystem.B.dylib             	0x00007fff837d59ce __semwait_signal_nocancel + 10
1   libSystem.B.dylib             	0x00007fff837d58d0 nanosleep$NOCANCEL + 129
2   libSystem.B.dylib             	0x00007fff838323ce usleep$NOCANCEL + 57
3   libSystem.B.dylib             	0x00007fff83851a00 abort + 93
4   libstdc++.6.dylib             	0x00007fff8791f5d2 __tcf_0 + 0
5   libobjc.A.dylib               	0x00007fff8116cb39 _objc_terminate + 100
6   libstdc++.6.dylib             	0x00007fff8791dae1 __cxxabiv1::__terminate(void (*)()) + 11
7   libstdc++.6.dylib             	0x00007fff8791db16 __cxxabiv1::__unexpected(void (*)()) + 0
8   libstdc++.6.dylib             	0x00007fff8791dbfc __gxx_exception_cleanup(_Unwind_Reason_Code, _Unwind_Exception*) + 0
9   libobjc.A.dylib               	0x00007fff81168fa2 object_getIvar + 0
10  com.apple.CoreFoundation      	0x00007fff800b45d7 +[NSException raise:format:arguments:] + 103
11  com.apple.CoreFoundation      	0x00007fff800b4564 +[NSException raise:format:] + 148
12  com.apple.AppKit              	0x00007fff8556086e -[NSPrintSpoolingGraphicsContext dealloc] + 37
13  com.apple.CoreFoundation      	0x00007fff80030fc3 __CFArrayReleaseValues + 435
14  com.apple.CoreFoundation      	0x00007fff8000eaa3 _CFRelease + 179
15  com.apple.AppKit              	0x00007fff8500b53d __NSAppKitFinalizeThreadData + 260
16  libSystem.B.dylib             	0x00007fff8379c751 _pthread_tsd_cleanup + 187
17  libSystem.B.dylib             	0x00007fff8379c39c _pthread_exit + 147
18  com.apple.Foundation          	0x00007fff83bd227f __NSFinalizeThreadData + 0
19  com.apple.Foundation          	0x00007fff83bd2217 __NSThread__main__ + 1448
20  libSystem.B.dylib             	0x00007fff8379bfd6 _pthread_start + 331
21  libSystem.B.dylib             	0x00007fff8379be89 thread_start + 13

..

please help

How to get the sensor data

Member 13027430 — Tue, 28 Feb 2017 01:56:00 GMT

I want to get the magnetic induction intensity, light intensity, the object distance phone

image from custom NSView , image quality is very bad.

Le@rner — Tue, 17 Jan 2017 05:50:00 GMT

hi all,

i have an image with god quality even when i view it in preview and zoom its gud and not pixelate.

i have create an custom view class derived from NSView, to draw text above and below the image. and resize the image

inside the custom view class in -drawRect method, i draw the text and image.

with help of NSMutableAttributedString drawinRect and NSImage drawInRect methods.

than get final image like this.

<pre lang="objc">
OffscreenView 	*view = [[OffscreenView alloc] initWithImage:myimage];
    
    
    NSRect			rect = [view bounds];
    NSData 			*data = [view dataWithPDFInsideRect:rect];
NSImage			*image_bar = [[NSImage alloc] initWithData:data];

buts this image quality is very badges compare to original image i pass to view.

please help me to get god quality image here.

Simultaneous Microphone Access on iPhone

Member 12377338 — Tue, 08 Mar 2016 11:35:00 GMT

Dear Members,

Is it possible for two apps to simultaneously access microphone under iPhone. We want to develop a Skype recorder for iPhone but need to determine the possibility.

In Android we were getting problem in shared access of microphone but on Windows 7 desktop shared mode for microphone worked.

Thanks,

Objective C first program from the book, warning messages

Alla__ — Tue, 10 Nov 2015 12:44:00 GMT

Hello!

I am new to this forum, and new to programming, although I have already reached chapter 18
of Programming in C textbook.

Please, take a look at the program I typed in from the book, and warning messages I receive.
I would be grateful for explanation on what I am doing wrong. I work on Mac OS 10.7.5, Xcode 4.6.3,
Terminal 2.2.3.
1) I created a file with the command:
touch prog18-2.m// Program ot work with fractions - Objective-C version

2) Program
#import <stdio.h>
#import <objc object.h="">

//------ @interface section ---------

@interface Fraction: Object
{
int numerator;
int denominator;
}
-(void) set_numerator: (int) n;
-(void) set_denominator: (int) d;
-(void) print;

@end

// ----- @implementation section -------

@implementation Fraction;

// getters
-(int) numerator
{
return numerator;
}

-(int) denominator
{
return denominator;
}

//setters
-(void) set_numerator: (int) num
{
numerator = num;
}

-(void) set_denominator: (int) denom
{
denominator = denom;
}

//other
-(void) print
{
printf("The value of the fraction is %i/%i\n", numerator, denominator);
}

@end

//-------- program section -----------

int main(void)
{
Fraction* my_fract;
my_fract = [Fraction new];

[my_fract set_numerator: 1];
[my_fract set_denominator: 3];

printf("The numerator is %i, and teh denominator is %i\n", [my_fract numerator], [my_fract denominator]);
[my_fract print];

[my_fract free]; //frees the memory that was used by Fraction object

return 0;
}

3) I compiled it with:
gcc -framework Foundation prog18-2.m -o prog18-2

4) Terminal generated the following:
prog18-2.m: In function ‘main’:
prog18-2.m:58: warning: ‘Fraction’ may not respond to ‘+new’
prog18-2.m:58: warning: (Messages without a matching method signature
prog18-2.m:58: warning: will be assumed to return ‘id’ and accept
prog18-2.m:58: warning: ‘...’ as arguments.)
prog18-2.m:71: warning: ‘Fraction’ may not respond to ‘-free’

Thank you!

Linker command failed with exit code 1 (use -v to see invocation) in xcode 5.1.1

Member 11983763 — Mon, 14 Sep 2015 20:17:00 GMT

Hi

I am getting the below error, when i try to compile xcode project.

duplicate symbol _squareOfDistanceBetweenPoints in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(AGSCPTUtilities.o)

/Users/project/map/libCorePlot-CocoaTouch.a(CPTUtilities.o)

duplicate symbol _niceNum in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(AGSCPTAxis.o)

/Users/project/map/libCorePlot-CocoaTouch.a(CPTAxis.o)

duplicate symbol _AddRoundedRectPath in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(AGSCPTPathExtensions.o)

/Users/project/map/libCorePlot-CocoaTouch.a(CPTPathExtensions.o)

duplicate symbol _CreateRoundedRectPath in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(AGSCPTPathExtensions.o)

/Users/project/map/libCorePlot-CocoaTouch.a(CPTPathExtensions.o)

duplicate symbol _dependentCoord in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(AGSCPTTradingRangePlot.o)

/Users/project/map/libCorePlot-CocoaTouch.a(CPTTradingRangePlot.o)

duplicate symbol _independentCoord in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(AGSCPTTradingRangePlot.o)

/Users/project/map/libCorePlot-CocoaTouch.a(CPTTradingRangePlot.o)

duplicate symbol _MyCGPathApplierFunc in:

/Users/Library/SDKs/ArcGIS/iOS/ArcGIS.framework/ArcGIS(NSCoderExtensions.o)

/Users/project/map/libCorePlot-CocoaTouch.a(NSCoderExtensions.o)

ld: 7 duplicate symbols for architecture i386

clang: error: linker command failed with exit code 1 (use -v to see invocation)

thanks in advance