Come posso creare un conto alla rovescia per cocos2d?
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22-07-2019 - |
Domanda
Sto sviluppando un gioco per iPhone 2D usando cocos2d. Ho bisogno di un conto alla rovescia. Come posso creare un conto alla rovescia in cocos2d?
Soluzione
Non abbastanza rappresentante per votare Tom, ma ha assolutamente ragione. Nel contesto di questa domanda, NSTimer è la soluzione ERRATA. Il framework Cocos2d fornisce un programmatore che si integra con altre funzionalità di gioco come Pause / Resume (e molto probabilmente utilizza NSTimer sotto il cofano).
Esempio dal link sopra:
-(id) init
{
if( ! [super init] )
return nil;
// schedule timer
[self schedule: @selector(tick:)];
[self schedule: @selector(tick2:) interval:0.5];
return self;
}
-(void) tick: (CCTime) dt
{
// bla bla bla
}
-(void) tick2: (CCTime) dt
{
// bla bla bla
}
Altri suggerimenti
http://www.cocos2d-iphone.org/wiki /doku.php/prog_guide:best_practices
- Prova NON per utilizzare NSTimer di Cocoa. Utilizza invece il proprio scheduler di cocos2d.
- Se usi lo scheduler cocos2d, avrai:
- pausa / riavvio automatico.
- quando il livello (Scene, Sprite, CocosNode) entra nel palcoscenico, il timer si attiverà automaticamente e quando lascia il palco verrà automaticamente disattivato.
- Il tuo target / selettore verrà chiamato con un delta time ...
In cocos 2d è presente la sezione di aggiornamento predefinita per il timer.
Prova questo:
[self schedule:@selector(update:)];
- (void)update:(ccTime)dt {
}
Per coloro che desiderano utilizzare NSTimer invece di " programma " metodo, è possibile creare una classe come la seguente:
ZIMCountdownTicker.h
#import <Foundation/Foundation.h>
extern NSString * const ZIMCountdownTickerTickAction;
extern NSString * const ZIMCountdownTickerResetAction;
@protocol ZIMCountdownTickerProtocol;
/*!
@class ZIMCountdownTicker
@discussion This class creates a countdown ticker.
@updated 2011-03-05
*/
@interface ZIMCountdownTicker : NSObject {
@private
NSTimer *_timer;
id<ZIMCountdownTickerProtocol> _delegate;
NSTimeInterval _interval;
double _period;
double _value;
}
/*!
@method initWithDelegate:withTimeInterval:forTimePeriod:
@discussion This method instantiate an instance of this class with the specified parameters.
@param delegate A reference to a class that has implemented ZIMCountdownTickerProtocol.
@param interval The time interval in seconds to be used when running the countdown ticker.
@param period The time period in seconds for which countdown ticker will run.
@updated 2011-03-05
*/
- (id) initWithDelegate: (id<ZIMCountdownTickerProtocol>)delegate withTimeInterval: (NSTimeInterval)interval forTimePeriod: (double)period;
/*!
@method start
@discussion This method will start the countdown ticker.
@updated 2011-03-05
*/
- (void) start;
/*!
@method stop
@discussion This method will stop the countdown ticker.
@updated 2011-03-05
*/
- (void) stop;
/*!
@method reset
@discussion This method will reset the countdown ticker.
@updated 2011-03-06
*/
- (void) reset;
/*!
@method value
@discussion This method will return the countdown ticker's current value; however, using this method will cause
the ticker to stop.
@return The countdown ticker's current value.
@updated 2011-03-05
*/
- (double) value;
@end
@protocol ZIMCountdownTickerProtocol <NSObject>
@optional
/*!
@method countdownTicker:didUpdateValue:withAction:
@discussion This method will notify the delegate with the current value.
@param ticker A reference to tiggering ticker.
@param value The current value.
@param action The action that tiggered this method.
@updated 2011-03-05
*/
- (void) countdownTicker: (ZIMCountdownTicker *)ticker didUpdateValue: (double)value withAction: (NSString *)action;
/*!
@method countdownTickerDidFinish:
@discussion This method will notify the delegate that the countdown ticker finished.
@param ticker A reference to tiggering ticker.
@updated 2011-03-05
*/
- (void) countdownTickerDidFinish: (ZIMCountdownTicker *)ticker;
@end
ZIMCountdownTicker.m
// Ziminji Classes
#import "ZIMCountdownTicker.h"
NSString * const ZIMCountdownTickerTickAction = @"ticker.tick";
NSString * const ZIMCountdownTickerResetAction = @"ticker.reset";
/*!
@category ZIMCountdownTicker (Private)
@discussion This category defines the prototypes for this class's private methods.
@updated 2011-03-05
*/
@interface ZIMCountdownTicker (Private)
/*!
@method countdown:
@discussion This method is called by the timer to decrement the counter's value and will send
the delegate the updated value.
@param timer The timer currently in use.
@updated 2011-03-06
*/
- (void) countdown: (NSTimer *)timer;
@end
@implementation ZIMCountdownTicker
- (id) initWithDelegate: (id<ZIMCountdownTickerProtocol>)delegate withTimeInterval (NSTimeInterval)interval forTimePeriod: (double)period {
if (self = [super init]) {
_delegate = delegate;
_interval = interval;
_period = period;
_value = period;
_timer = nil;
}
return self;
}
- (void) start {
if (_timer == nil) {
_timer = [NSTimer scheduledTimerWithTimeInterval: _interval target: self selector: @selector(countdown:) userInfo: nil repeats: YES];
}
}
- (void) stop {
if (_timer != nil) {
[_timer invalidate];
_timer = nil;
}
}
- (void) reset {
[self stop];
_value = _period;
if ((_delegate != nil) && [_delegate respondsToSelector: @selector(countdownTicker:didUpdateValue:withAction:)]) {
[_delegate countdownTicker: self didUpdateValue: _value withAction: ZIMCountdownTickerResetAction];
}
}
- (double) value {
[self stop];
return _value;
}
- (void) countdown: (NSTimer *)timer {
_value -= 1;
if ((_delegate != nil) && [_delegate respondsToSelector: @selector(countdownTicker:didUpdateValue:withAction:)]) {
[_delegate countdownTicker: self didUpdateValue: _value withAction: ZIMCountdownTickerTickAction];
}
if (_value <= 0) {
[self stop];
if ((_delegate != nil) && [_delegate respondsToSelector: @selector(countdownTickerDidFinish:)]) {
[_delegate countdownTickerDidFinish: self];
}
}
}
- (void) dealloc {
if (_delegate != nil) {
[_delegate release];
}
if (_timer != nil) {
[_timer invalidate];
}
[super dealloc];
}
@end
Guarda NSTimer, molto probabilmente può fornire qualsiasi funzionalità timer necessaria.
-(id) init
{
if( ! [super init] )
return nil;
// schedule timer
[self schedule: @selector(tick:)];
[self schedule: @selector(tick2:) interval:0.5];
return self;
}
-(void) tick: (ccTime) dt
{
//some function here
}
-(void) tick2: (ccTime) dt
{
//some function here
}