层更新不会在cocos2d-iphone中调用 [英] layer update does not get called in cocos2d-iphone

问题描述

我在建立并运行我的iPad上的应用程序时没有调用HelloWorldLayer类'update：method'的问题。

以下是HelloWorldLayer的实现：

  //导入接口
 #importHelloWorldLayer.h
 
 //需要获取导航控制器
 #import AppDelegate.h
 
 const float MaxPlayerAccel = 400.0f; 
 const float MaxPlayerSpeed = 200.0f; 
 
 #pragma mark  -  HelloWorldLayer 
 
 // HelloWorldLayer实现
 @implementation HelloWorldLayer 
 {
 CGSize _winSize; 
 CCSprite * _playerSprite; 
 UIAccelerationValue _accelerometerX; 
 UIAccelerationValue _accelerometerY; 
 
 float _playerAccelX; 
 float _playerAccelY; 
 float _playerSpeedX; 
 float _playerSpeedY; 
} 
 
 //帮助程序类方法创建一个场景，HelloWorldLayer作为唯一的孩子。 
 +（CCScene *）场景
 {
 //'scene'是一个自动释放对象。 
 CCScene * scene = [CCScene node]; 
 
 //'layer'是一个autorelease对象。 
 HelloWorldLayer * layer = [HelloWorldLayer node]; 
 
 //将图层作为子级添加到场景
 [scene addChild：layer]; 
 
 //返回场景
 return scene; 
} 
 
 //在init你需要初始化你的实例
 
  - （id）init 
 {
 if = [super initWithColor：ccc4（94，63，107，255）]）
 {
 _winSize = [CCDirector sharedDirector] .winSize; 
 
 _playerSprite = [CCSprite spriteWithFile：@Player-hd.png]; 
 _playerSprite.position = ccp（_winSize.width  -  50.0f，50.0f）; 
 [self addChild：_playerSprite]; 
 self.accelerometerEnabled = YES; 
 NSLog（@init：method executed）; 
} 
 return self; 
} 
 
  - （void）加速度计：（UIAccelerometer *）加速度计didAccelerate：（UIAcceleration *）加速度
 {
 const double FilteringFactor = 0.75; 
 
 _accelerometerX = acceleration.x * FilteringFactor + _accelerometerX *（1.0  -  FilteringFactor）; 
 _accelerometerY = acceleration.y * FilteringFactor + _accelerometerY *（1.0  -  FilteringFactor）; 
 
 if（_accelerometerY> 0.05）
 {
 _playerAccelX = -MaxPlayerAccel; 
} 
 else if（_accelerometerY <0.05）
 {
 _playerAccelX = MaxPlayerAccel; 
} 
 
 if（_playerAccelX <-0.05）
 {
 _playerAccelY = -MaxPlayerAccel; 
} 
 else if（_playerAccelX> -0.05）
 {
 _playerAccelY = MaxPlayerAccel; 
} 
} 
 
  - （void）update：（ccTime）dt 
 {
 NSLog（@update：method is being called 
 // 1 
 _playerSpeedX + = _playerAccelX * dt; 
 _playerSpeedY + = _playerAccelY * dt; 
 
 // 2 
 _playerSpeedX = fmaxf（fminf（_playerSpeedX，MaxPlayerSpeed）， -  MaxPlayerSpeed）; 
 _playerSpeedY = fmaxf（fminf（_playerSpeedY，MaxPlayerSpeed）， -  MaxPlayerSpeed）; 
 
 // 3 
 float newX = _playerSprite.position.x + _playerSpeedX * dt; 
 float newY = _playerSprite.position.y + _playerSpeedY * dt; 
 
 // 4 
 newX = MIN（_winSize.width，MAX（newX，0））; 
 newY = MIN（_winSize.height，MAX（newY，0））; 
 
 _playerSprite.position = ccp（newX，newY）; 
} 
 
 @end 
  

解决方案>

您需要在init方法中计划更新：

  [self scheduleUpdate]; 
  

编辑：另外，碰巧看到代码的另一个可能的问题 - as image-hd.png 。在Cocos2D中，您只需要命名该文件，而不使用-hd前缀： image.png ，如果屏幕是retina则会自动选择HD版本。

I'm having an issue with the HelloWorldLayer class' update: method not being called when building and running the applications on my iPad.

Not really sure what the issue is as init: and accelerometer: didAccelerate: are called as expected.

Here is the implementation of HelloWorldLayer:

// Import the interfaces
#import "HelloWorldLayer.h"

// Needed to obtain the Navigation Controller
#import "AppDelegate.h"

const float MaxPlayerAccel = 400.0f;
const float MaxPlayerSpeed = 200.0f;

#pragma mark - HelloWorldLayer

// HelloWorldLayer implementation
@implementation HelloWorldLayer
{
    CGSize _winSize;
    CCSprite *_playerSprite;
    UIAccelerationValue _accelerometerX;
    UIAccelerationValue _accelerometerY;

    float _playerAccelX;
    float _playerAccelY;
    float _playerSpeedX;
    float _playerSpeedY;
}

// Helper class method that creates a Scene with the HelloWorldLayer as the only child.
+(CCScene *) scene
{
        // 'scene' is an autorelease object.
    CCScene *scene = [CCScene node];

    // 'layer' is an autorelease object.
    HelloWorldLayer *layer = [HelloWorldLayer node];

    // add layer as a child to scene
    [scene addChild: layer];

    // return the scene
    return scene;
}

// on "init" you need to initialize your instance

- (id)init
{
    if (self = [super initWithColor:ccc4(94, 63, 107, 255)])
    {
        _winSize = [CCDirector sharedDirector].winSize;

        _playerSprite = [CCSprite spriteWithFile:@"Player-hd.png"];
        _playerSprite.position = ccp(_winSize.width - 50.0f, 50.0f);
        [self addChild:_playerSprite];
        self.accelerometerEnabled = YES;
        NSLog(@"init: method executed");
    }
    return self;
}

- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration     *)acceleration
{
    const double FilteringFactor = 0.75;

    _accelerometerX = acceleration.x * FilteringFactor + _accelerometerX * (1.0 - FilteringFactor);
    _accelerometerY = acceleration.y * FilteringFactor + _accelerometerY * (1.0 - FilteringFactor);

    if (_accelerometerY > 0.05)
    {
        _playerAccelX = -MaxPlayerAccel;
    }
    else if (_accelerometerY < 0.05)
    {
        _playerAccelX = MaxPlayerAccel;
    }

    if (_playerAccelX < -0.05)
    {
        _playerAccelY = -MaxPlayerAccel;
    }
    else if (_playerAccelX > -0.05)
    {
        _playerAccelY = MaxPlayerAccel;
    }
}

- (void)update:(ccTime)dt
{
    NSLog(@"update: method is being called");
    // 1
    _playerSpeedX += _playerAccelX * dt;
    _playerSpeedY += _playerAccelY * dt;

    // 2
    _playerSpeedX = fmaxf(fminf(_playerSpeedX, MaxPlayerSpeed), - MaxPlayerSpeed);
    _playerSpeedY = fmaxf(fminf(_playerSpeedY, MaxPlayerSpeed), - MaxPlayerSpeed);

    // 3
    float newX = _playerSprite.position.x + _playerSpeedX * dt;
    float newY = _playerSprite.position.y + _playerSpeedY * dt;

    // 4
    newX = MIN(_winSize.width, MAX(newX, 0));
    newY = MIN(_winSize.height, MAX(newY, 0));

    _playerSprite.position = ccp(newX, newY);
}  

@end

解决方案

You need to schedule the update in your init method:

[self scheduleUpdate];

Edit: Also, happened to see another possible issue with your code - you're loading the sprite image as image-hd.png. In Cocos2D, you only need to name the file without the -hd prefix: image.png, and it will automatically select the HD version if the screen is retina.

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