I've got this code in my viewController.m file
- (void)viewDidLoad {
[super viewDidLoad];
GameLogic *_game = [[GameLogic alloc] init];
[_game initGame];
.......
}
GameLogic is another class which I created.
in the same viewController.m file, I have got another function
- (void)test {
if([_game returnElecFence]) //[_game returnsElecFence] causes the error
{
NSLog(#"YES");
}
else {
NSLog(#"NO");
}
.......
}
Problem is, whenever the test function is called, I get an error saying '_game' undeclared. I tried putting the GameLogic init code in the .h file and on top of the #implementation to make it global but every method I tried resulted in a worse error. TIA to anyone who can suggest some ideas to clear this error up
_game is a local variable. Its scope is only the method in which it's declared (viewDidLoad in this case).
You need to make _game a global variable, or better yet, an instance variable of your viewController class so that it can be accessed by all methods of the class.
Related
In a test Swift project, I am subclassing NSWindowController. My NSWindowController subclass is designed to work with a particular Nib file. It is desirable, then, that when my window controller is initialized, the nib file is automatically loaded by the window controller instance. In Objective-C, this was achieved by doing:
#implementation MyWindowController
- (id)init {
self = [super initWithWindowNibName:"MyWindowNib"]
if (self) {
// whatever
}
return self
}
#end
Now, in Swift this is not possible: init() cannot call super.init(windowNibName:), because the later is declared not as a designated initializer, but as a convenience one by NSWindowController.
How can this be done in Swift? I don't see a strightforward way of doing it.
P.S.: I have seen other questions regarding this topic, but, as long as I've been able to understand, the solutions all point to initialize the Window Controller by calling init(windowNibName:). Please note that this is not the desired beheaviour. The Window Controller should be initialized with init(), and it should be the Window Controller itself who "picks up" its Nib file and loads it.
If you use the init() just to call super.init(windowNibName:), you could instead just override the windowNibName variable.
override var windowNibName: String {
get {
return "MyWindowNib"
}
}
Then there should be no need to mess with the initializers.
You can create your own convenience initializer instead:
override convenience init() {
self.init(windowNibName: "MyWindowNib")
}
You should instead opt in to replacing all designated initializers in your subclass, simply delegating to super where appropriate. Confer https://stackoverflow.com/a/24220904/1460929
I don't under why the error: Use of undeclared identifier 'KCLDistanceFilterNone' and 'kCLLocationAccuracyHundredMeters' keeps coming up for my CoreLocation.m folder. There are also many more errors even when I deleted the ";" from select lines. Can someone please help?
#import "CoreLocation.h"
#implementation CoreLocation : NSObject
- (NSString *)deviceLocation {
NSString *theLocation = [NSString stringWithFormat:#"latitude: %f longitude: %f", locationManager.location.coordinate.latitude, locationManager.location.coordinate.longitude];
return theLocation;
}
- (void)viewDidLoad
{
locationManager = [[locationManager alloc] init];
locationManager.distanceFilter = kCLDistanceFilterNone;
locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters;
[locationManager startUpdatingLocation];
}
#end
Also, what would I put in my CoreLocation.m folder to complement this and complete the location services for my application?
A couple of thoughts:
Have you included the CoreLocation.framework in the list of linked libraries/frameworks?
Have you done the import of CoreLocation.framework header?
#import <CoreLocation/CoreLocation.h>
I wouldn't have thought that CoreLocation is a good name for your class, because of the confusion between the above line, and your line that says:
#import "CoreLocation.h"
It should work (having both of those lines), but it seems unnecessarily confusing (and risks problems associated with #import's feature that automatically prevents loading the same .h file twice).
I'd suggest give your custom CoreLocation class (a) a unique name that doesn't risk confusion with the existing headers; and (b) a more meaningful name that indicates what it's doing (e.g. CoreLocationUtilities or AppCoreLocationManager or whatever).
Your alloc/init method line references a variable name:
locationManager = [[locationManager alloc] init];
It should presumably reference a class name, e.g.:
locationManager = [[CLLocationManager alloc] init];
It makes me wonder how you defined the locationManager instance variable if you didn't get an error on that line.
Unrelated to your issue, I'm confused by your reference of your custom CoreLocation class being a NSObject subclass, but then having a viewDidLoad method, which is typically a view controller method. That seems to only further muddy the waters.
I want override all methods of a subclass automatically on xcode, for example I have a class extended of UiViewControler, how I override all methods of UiViewController on xcode to be more or less well:
- (id) init
{
return [super init];
}
My intention with this is to log all methods to see when they are called, then my methods will be more or less well
- (id) init
{
[self log];
return [super init];
}
where log is as follow method:
-(void) log
{
NSLog(#"%#",[(NSString *) (NSArray *) [NSThread callStackSymbols][1] componentsSeparatedByString:#"-["][1]);
}
thanks a lot!
In this case you don't have to do anything. If you don't provide an implementation, then the superclass's implementation will be used.
Edited after the question was edited
If you put the log statement in the superclass's implementation then it doesn't matter what you do with your own initialiser.
Why?
One of the many conventions in Cocoa is that each class has a designated initialiser. All the other designated initialisers then call this initialiser. And when you subclass the class, then you create a new designated initialiser for the new class, and as part of the initialisation - this calls the superclass's designated initialiser.
Which is why you see NSObject subclass initialisers calling [super init], because NSObject's designated initialiser is init.
So, just call your logging method in the designated initialiser of your class, and as long as you follow the above convention, this initialiser will always be called by a subclass, and so your logging method will always be called.
I have a singleton in my FTP app designed to store all of the types of servers that the app can handle, such as FTP or Amazon S3. These types are plugins which are located in the app bundle. Their path is located by applicationWillFinishLoading: and sent to the addServerType: method inside the singleton to be loaded and stored in an NSMutableDictionary.
My question is this:
How do I bind an NSDictionaryController to the dictionary inside the singleton instance? Can it be done in IB, or do I have to do it in code? I need to be able to display the dictionary's keys in an NSPopupButton so the user can select a server type.
Thanks in advance!
SphereCat1
I found / made up the answer to this: I simply override the init method so when it's called from the XIB file, it still returns the singleton. I then provide a method named realInit to do an actual initialization the first time init is called.
Code:
-(id)init
{
#synchronized(self)
{
if (_sharedInstance == nil)
{
_sharedInstance = [[VayprServerTypes alloc] realInit];
}
}
[self release];
return _sharedInstance;
}
-(id)realInit
{
if (self = [super init])
{
serverTypesArray = [[NSMutableArray alloc] init];
}
return self;
}
EDIT: Of course you'll need to define _sharedInstance as a static variable at the top of your class implementation:
static ClassTypeGoesHere *_sharedInstance;
ALSO EDIT: Since you now know for sure that your init method will be called at least once, you can go ahead and replace your normal singleton sharedInstance method with this:
+(ClassTypeGoesHere *)sharedInstance
{
return _sharedInstance;
}
If anyone sees any obvious problems with this design, please let me know!
SphereCat1
I noticed NSSpeechRecognizer in ADC library and I found it to be very interesting, so to play with it I prepared a simple application which will just listen the command and if recognized it displays it in log.
The code used is:
- (id)init {
if (self = [super init]) {
// Insert code here to initialize your application
NSArray *cmds = [NSArray arrayWithObjects:#"A",#"B", #"C",#"alpha",#"beta",#"vodka",#"wine",nil];
recog = [[NSSpeechRecognizer alloc] init]; // recog is an ivar
[recog setCommands:cmds];
[recog setDelegate:self];
}
return self;
}
- (IBAction)listen:(id)sender
{ NSLog(#"listen:");
if ([sender state] == NSOnState) { // listen
[recog startListening];
} else {
[recog stopListening];
}
}
- (void)speechRecognizer:(NSSpeechRecognizer *)sender didRecognizeCommand:(id)aCmd {
NSLog(#"speechRecognizer: %#",(NSString *)aCmd);
}
I tried it many times for the commands registered but I was unable to get none of the messages in log, in delegate :(
There was always some noise in the background.. could this be the reason for it or I have done something wrong in the code??
Can anyone suggest me some solution for it??
Thanks,
Miraaj
Code looks fine so far.
The NSSpeechRecognizer is a bit tricky sometimes and refuses to listen to the right words. Did you try different words?
Did you try setting startListening as default?
I wrote a little tutorial some time ago. Its in german language but maybe it will help you anyway or you use some translation tool.
http://cocoa-coding.de/spracherkennung/nsspeechrecognizer1.html