一、九宮格
1.1 ****方法****1 ****只能創建（****ij****）個對象*

#define WINDOW_WIDTH self.window.bounds.size.width
#define WINDOW_HEIGHT self.window.bounds.size.height
#define IMAGE_WIDTH 60
#define IMAGE_HEIGHT 60
#import "AppDelegate.h"

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    
    //1.根據屏幕寬高，計算行間距、列間距
    float rowSpace = (WINDOW_HEIGHT - 3 * 60) / 4;
    float colSpace = (WINDOW_WIDTH - 3 * 60) / 4;
    
    for (int i = 0 ; i < 3; i++)
    {
        float y = rowSpace + i * (rowSpace + IMAGE_HEIGHT);
        for (int j = 0; j < 3; j++)
        {
            float x = colSpace + j * (colSpace + IMAGE_WIDTH);
            
            UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(x, y, IMAGE_WIDTH, IMAGE_HEIGHT)];
            imageView.backgroundColor = [UIColor redColor];
            [self.window addSubview:imageView];
        }
    }
    
    return YES;
}

1.2 ****方法****2 ****創建任意個對象

#define SCREEN_WIDTH [[UIScreen mainScreen]bounds].size.width
#define SCREEN_HEIGHT [[UIScreen mainScreen]bounds].size.height
#define IMAGE_WIDTH 60
#define IMAGE_HEIGHT 60
#import "AppDelegate.h"

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    
    //1.求行間距、列間距
    float rowSpace = (SCREEN_HEIGHT - 3 * IMAGE_HEIGHT)/4;
    float colSpace = (SCREEN_WIDTH - 3 * IMAGE_WIDTH)/4;
    
    //2.for循環
    //a：要創建的對象數
    for (int a = 0; a < 8; a++)
    {
        //1.計算行號和列號。注意：3代表多少列
        //1.1 行號：對3求整
        int i = a/3;
        //1.2 列號：對3求余
        int j = a%3;
        
        //2.計算x，y坐標
        float x = colSpace + j * (colSpace + IMAGE_WIDTH);
        float y = rowSpace + i * (rowSpace + IMAGE_HEIGHT);
        
        //3.創建圖片
        UIImageView *imgView = [[UIImageView alloc]initWithFrame:CGRectMake(x, y, IMAGE_WIDTH, IMAGE_HEIGHT)];
        imgView.backgroundColor = [UIColor blueColor];
        [self.window addSubview:imgView];
    }
    
    return YES;
}

2.****創建****Tom****貓按鈕
2.1 主函數

//1.添加圖片視圖，展示背景圖片，同時實現幀動畫效果
    _catImgView = [[UIImageView alloc]initWithFrame:self.window.frame];
    _catImgView.image = [UIImage imageNamed:@"angry_01.jpg"];
    [self.window addSubview:_catImgView];
    
    //2.將按鈕的圖片名字、圖片數量，存放到數組中
    _btnImgNameArray = [[NSArray alloc]initWithObjects:@"cymbal",@"drink",@"eat",@"fart",@"pie",@"scratch", nil];
    _numberArry = [[NSArray alloc]initWithObjects:@"13",@"81",@"40",@"28",@"24",@"56", nil];
    
    //3.創建6個點擊按鈕
    for (int a = 0; a < 6; a++)
    {
        //1.列號 對2求余
        int i = a%2;
        float x = 0;
        //3目運算符，與下面if.else語句一樣
//        float x = (i == 0) ? 30 : 230;
        if (i == 0)
        {
            x = 30;
        }
        else
        {
            x = 230;
        }
        //行號
        int j = a/2;
        float y = 0;
        y = 240 + j * (ROW_SPACE + BUTTON_HEIGHT);
        
        //根據索引值(a)取出圖片名字
        NSString *name = [_btnImgNameArray objectAtIndex:a];
        
        //創建按鈕
        UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
        button.frame = CGRectMake(x, y, BUTTON_WIDTH, BUTTON_HEIGHT);
        [button setImage:[UIImage imageNamed:name] forState:UIControlStateNormal];
        [button addTarget:self action:@selector(animationClick:) forControlEvents:UIControlEventTouchUpInside];
        button.tag = a;
        [self.window addSubview:button];
    }
    
    
    return YES;

2.2 ****代碼封裝

//將重復性的代碼封裝為方法
//參數：
//1.圖片名
//2.圖片數量
- (void)tomAnimationWithImageName:(NSString *)imageName number:(int)number
{
    if (_catImgView.isAnimating == YES)
    {
        return;
    }
    NSMutableArray *imgArray = [[NSMutableArray alloc]init];
    for (int i = 0; i < number; i++)
    {
        NSString *name = [NSString stringWithFormat:@"%@_%02d.jpg",imageName,i];
        UIImage *image = [UIImage imageNamed:name];
        [imgArray addObject:image];
    }
    _catImgView.animationDuration = 0.1 * imgArray.count;
    _catImgView.animationImages = imgArray;
    _catImgView.animationRepeatCount = 1;
    [_catImgView startAnimating];
}

//點擊按鈕，創建圖片數組，實現三個屬性、一個方法
- (void)animationClick:(UIButton *)button
{
    //方法1
    NSString *name = [_btnImgNameArray objectAtIndex:button.tag];
    NSString *numStr =[_numberArry objectAtIndex:button.tag];
    int num = [numStr intValue];
    [self tomAnimationWithImageName:name number:num];
}

1.****屏幕寬高，按鈕寬高
2.

**x = colSpace + i * ****（****colSpace + width****）**
**y = rowSpace + j * ****（****rowSpace + height****）**

1.用定時器，制作一個橢圓運動效果
a.中點坐標
b.根據半徑求園坐標
宏定義：中點坐標x/y，半徑，

2.雪花下落，多片