cocos2d笔记 （2）解析cocos2d项目整体框架和启动流程

在这里我们新建一个名为“Test2d”的项目，在xcode中的Group&Files中看到的文件结构如下所示：

cocos2d Sources：存放的是cocos2d源代码

Classes：存放本应用程序源代码

Other Sources:   程序的入口main函数

Resources：存放本项目的图片、图标、声音文件等等

Frameworks：框架

 

顺一下启动流程

从main函数进入：

 

#import <UIKit/UIKit.h>

int main(int argc, char *argv[]) {
	NSAutoreleasePool *pool = [NSAutoreleasePool new];
	int retVal = UIApplicationMain(argc, argv, nil, @"Test2dAppDelegate");
	[pool release];
	return retVal;
}　

第5行标识将程序的控制权传递给了应用代理程序对象Test2dAppDelegate

 

 

Test2dAppDelegate

Test2dAppDelegate头文件如下

 

#import <UIKit/UIKit.h>

@interface Test2dAppDelegate : NSObject <UIApplicationDelegate> {
	UIWindow *window;
}

@property (nonatomic, retain) UIWindow *window;

@end

第三行能看出Test2dAppDelegate实现了系统定义的应用程序接口 UIApplicationDelegate

 

当前应用程序需要处理的各种系统事件:

 放弃控制权:applicationWillResignActive  获得控制权:applicationDidBecomeActive  内存报警:applicationDidReceiveMemoryWarning  程序退出提示:applicationWillTerminate  系统时间变化:applicationSignificantTimeChange

 

//放弃控制权
- (void)applicationWillResignActive:(UIApplication *)application {
	[[CCDirector sharedDirector] pause];
}

//获得控制权
- (void)applicationDidBecomeActive:(UIApplication *)application {
	[[CCDirector sharedDirector] resume];
}

//内存报警
- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application {
	[[CCDirector sharedDirector] purgeCachedData];
}

//
-(void) applicationDidEnterBackground:(UIApplication*)application {
	[[CCDirector sharedDirector] stopAnimation];
}

//
-(void) applicationWillEnterForeground:(UIApplication*)application {
	[[CCDirector sharedDirector] startAnimation];
}

//程序退出提示
- (void)applicationWillTerminate:(UIApplication *)application {
	[[CCDirector sharedDirector] end];
}

//系统时间变化
- (void)applicationSignificantTimeChange:(UIApplication *)application {
	[[CCDirector sharedDirector] setNextDeltaTimeZero:YES];
}

 

在完成刜始处理之后,通过凼数 applicationDidFinishLaunching 将程序的控制权传递给 Cocos2D-iPhone 类库,Cocos2D-iPhone 接下来开始准备启劢 游戏主画面的准备:

1.获得主窗口对象(句柄)由成员 window 保存。
2.将 Cocos2D-iPhone 的“导演”对象与之绑定。
3. 设置“导演”对象的基本属性。

 

- (void) applicationDidFinishLaunching:(UIApplication*)application
{
	// CC_DIRECTOR_INIT()
	//
	// 1. Initializes an EAGLView with 0-bit depth format, and RGB565 render buffer
	// 2. EAGLView multiple touches: disabled
	// 3. creates a UIWindow, and assign it to the "window" var (it must already be declared)
	// 4. Parents EAGLView to the newly created window
	// 5. Creates Display Link Director
	// 5a. If it fails, it will use an NSTimer director
	// 6. It will try to run at 60 FPS
	// 7. Display FPS: NO
	// 8. Device orientation: Portrait
	// 9. Connects the director to the EAGLView
	//
	CC_DIRECTOR_INIT();
	
	// Obtain the shared director in order to...
	CCDirector *director = [CCDirector sharedDirector];
	
       /***********设置“导演”对象的基本属性***************/
　　   //设置主窗口方向（垂直还是水平）
	// Sets landscape mode
	[director setDeviceOrientation:kCCDeviceOrientationLandscapeLeft];

	//是否显示FPS（每秒显示的帧数）
	// Turn on display FPS
	[director setDisplayFPS:YES];
	
　　　//设定Director对象与当前窗口的关系，便于Director操作主窗口
	// Turn on multiple touches
	EAGLView *view = [director openGLView];
	[view setMultipleTouchEnabled:YES];
	
	//设定主窗口显示图像的调色盘位宽
　　　// Default texture format for PNG/BMP/TIFF/JPEG/GIF images
	// It can be RGBA8888, RGBA4444, RGB5_A1, RGB565
	// You can change anytime.
	[CCTexture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_RGBA8888];	
	
        //导演对象启动并运行场景
	[[CCDirector sharedDirector] runWithScene: [HelloWorld scene]];
}

 

Cocos2d-iPhone的主画面对象 – HellowWorldScene 场景

场景对象 HellowWorldScence 获得控制权后通过初始化凼数 init,直接在主画面中创建一个带有“Hello world”内容的Lable。将该标签的位置为屏幕的中央。

 

-(id) init
{
	// always call "super" init
	// Apple recommends to re-assign "self" with the "super" return value
	if( (self=[super init] )) {
		
		// create and initialize a Label
		CCLabel* label = [CCLabel labelWithString:@"Hello World" fontName:@"Marker Felt" fontSize:64];

		// ask director the the window size
		CGSize size = [[CCDirector sharedDirector] winSize];
	
		// position the label on the center of the screen
		label.position =  ccp( size.width /2 , size.height/2 );
		
		// add the label as a child to this Layer
		[self addChild: label];
	}
	return self;
}

 

Cocos2D-iPhone 的基本导入框架就是:

 1)确保 main 凼数调用正确的 应用程序代理对象。 

2) 在应用代理对象的 applicationDidFinishLaunching 凼数中

a) 创建“层“对象。 b) 将层传递给新创建的“场景“ c) 通过“导演“对象运行新建的”场景“对象。