NSNotificationCenter通知中心（用於一對多的通知）

//發送端：
 [NSNotificationCenter.defaultCenter postNotificationName:@"playIntro" object:self];

//接收端：
 [NSNotificationCenter.defaultCenter addObserver:self selector:@selector(playIntro) name:@"playIntro" object:self.moviePlayer];

 //接收後註銷：
 [NSNotificationCenter.defaultCenter removeObserver:self name:@"playIntro" object:self.moviePlayer];

Iterative與Recursive的差異

迭代法以確定的部分作為起始點，循序漸進推演，最後求得答案。

遞迴法找出一套縮小問題範疇的規律，以此規律不斷縮小問題，直到能釐清細節，找到確定的部份。

迭代法與遞迴法恰好顛倒：迭代法是針對已知，逐步累積，直至周全；遞迴法是針對未知，反覆拆解，直至精細。

截自http://www.csie.ntnu.edu.tw/~u91029/IterativeRecursive.html

開場影片

//最好調整成放在AppDelegate中，因為View不會那麼早被初始化

header, #import <MediaPlayer/MediaPlayer.h>

@interface RootViewController ()

{  

}

@property (nonatomic, strong) MPMoviePlayerController *moviePlayer;

@end

@implementation RootViewController

@synthesize moviePlayer;

-(void)playIntro{

    NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:@"appIntro" ofType:@"mp4"]];

    self.moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:url];

    //註冊通知中心，當影片播放完畢，進行回呼方法(playbackStateDidFinish)

    [[NSNotificationCenter defaultCenter] addObserver:self

                                             selector:@selector(playbackStateDidFinish)

                                                 name:MPMoviePlayerPlaybackDidFinishNotification

                                               object:self.moviePlayer ];

    //播放器參數設定

    self.moviePlayer.controlStyle = MPMovieControlStyleNone;

    self.moviePlayer.scalingMode = MPMovieScalingModeAspectFill;

    self.moviePlayer.repeatMode = MPMovieRepeatModeNone;

    self.moviePlayer.view.autoresizingMask = UIViewAutoresizingFlexibleBottomMargin|UIViewAutoresizingFlexibleLeftMargin

   |UIViewAutoresizingFlexibleRightMargin|UIViewAutoresizingFlexibleTopMargin;

    //設定播放器大小

    [self.moviePlayer.view setFrame:self.view.bounds];

    [self.view addSubview:self.moviePlayer.view];

    //播放

    [self.moviePlayer play];

}

- (void)playbackStateDidFinish{

    //註銷通知中心

    [[NSNotificationCenter defaultCenter] removeObserver:self

                                                    name:MPMoviePlayerPlaybackDidFinishNotification

                                                  object:self.moviePlayer];

    //停止播放

    [self.moviePlayer stop];

    //移除播放器

    [self.moviePlayer.view removeFromSuperview];

}

UIWebView截取html

//載取html改變頁面寬度後塞回
- (void)webViewDidFinishLoad:(UIWebView *)webView

{

//修改頁面meta值

NSString *meta = [NSString stringWithFormat:@"document.getElementsByName(\"viewport\")[0].content = \"width=%f, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no\"", webView.frame.size.width];

[webView stringByEvaluatingJavaScriptFromString:meta];

}

//增加UTF-8編碼

 [webView stringByEvaluatingJavaScriptFromString:  @"var tagHead =document.documentElement.firstChild;" 
"var tagMeta = document.createElement(\"meta\");"
"tagMeta.setAttribute(\"http-equiv\", \"Content-Type\");"   "tagMeta.setAttribute(\"content\", \"text/html; charset=utf-8\");"
"var tagHeadAdd = tagHead.appendChild(tagMeta);"]; 

//截取網頁圖片,修改圖片大小

[webView stringByEvaluatingJavaScriptFromString:

@"var script = document.createElement('script');"

"script.type = 'text/javascript';"

"script.text = \"function ResizeImages() { "

"var myimg,oldwidth;"

"var maxwidth=380;" //頁面寬度

"for(i=0;i <document.images.length;i++){"

"myimg = document.images[i];"

"if(myimg.width > maxwidth){"

"oldwidth = myimg.width;"

"myimg.width = maxwidth;"

"myimg.height = myimg.height * (maxwidth/oldwidth);"

"}"

"}"

"}\";"

"document.getElementsByTagName('head')[0].appendChild(script);"];

 

[webView stringByEvaluatingJavaScriptFromString:@"ResizeImages();"];  

旋轉手勢辨識

#import <UIKit/UIKit.h>

@interface MyImageView : UIImageView{

    CGPoint startPoint;

    CGAffineTransform currentTransform;

}

@end

#import "MyImageView.h"

#import <QuartzCore/QuartzCore.h>

@implementation MyImageView

- (id)initWithFrame:(CGRect)frame

{

    self = [super initWithFrame:frame];

    if (self) {

        // Initialization code

    }

    return self;

}

-(id)initWithCoder:(NSCoder* )aDecoder{

    self = [super initWithCoder:aDecoder];

    if (self) {

        //啟動觸控

        self.userInteractionEnabled= YES;

        //設定圖檔

        self.image = [UIImage imageNamed:@"image4.jpg"];

        //加入手勢

        

        /*

        UIPanGestureRecognizer* pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(doMove:)];

        [self addGestureRecognizer:pan];

        */

        /*

        UISwipeGestureRecognizer* swipe1 = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(doLeft:)];

        swipe1.direction = UISwipeGestureRecognizerDirectionLeft;

        //要求雙擊

        swipe1.numberOfTouchesRequired = 2;

        [self addGestureRecognizer:swipe1];

        

        UISwipeGestureRecognizer* swipe2 = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(doRight:)];

        //要求雙擊

        swipe2.numberOfTouchesRequired = 2;

        swipe2.direction = UISwipeGestureRecognizerDirectionRight;

        [self addGestureRecognizer:swipe2];

        */

        

        UIRotationGestureRecognizer* rotation= [[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(doRotate:)];

        [self addGestureRecognizer:rotation];

        

    }

    return self;

}

-(void)doRotate:(UIRotationGestureRecognizer*)recognizer{

    //從recognizer中取得並旅轉

    self.layer.affineTransform = CGAffineTransformRotate(currentTransform, recognizer.rotation);

}

-(void)doLeft:(UISwipeGestureRecognizer*)recognizer{

    CGPoint newPoint = CGPointMake(self.center.x-50, self.center.y);

    self.center = newPoint;

}

-(void)doRight:(UISwipeGestureRecognizer*)recognizer{

    CGPoint newPoint = CGPointMake(self.center.x+50, self.center.y);

    self.center = newPoint;

}

/*

-(void)doMove:(UIPanGestureRecognizer*)recognizer{

    //取得解控點

    CGPoint clickPoint = [recognizer translationInView:self];

    NSLog(@"Move的點是(%.1f,%.1f)",clickPoint.x,clickPoint.y);

    //開始移動

    CGPoint newPoint = CGPointMake(startPoint.x+clickPoint.x, startPoint.y+clickPoint.y);

    self.center = newPoint;

}

*/

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

    //取得觸控點

    CGPoint clickPoint = [[touches anyObject]locationInView:self];

    NSLog(@"觸控點在(%.1f,%.1f)",clickPoint.x,clickPoint.y);

    startPoint = clickPoint;

    currentTransform=self.layer.affineTransform;

}

/*

// Only override drawRect: if you perform custom drawing.

// An empty implementation adversely affects performance during animation.

- (void)drawRect:(CGRect)rect

{

    // Drawing code

}

*/

@end

滑動手勢辨識

#import <UIKit/UIKit.h>

@interface MyImageView : UIImageView{

    CGPoint startPoint;

}

@end

#import "MyImageView.h"

@implementation MyImageView

- (id)initWithFrame:(CGRect)frame

{

    self = [super initWithFrame:frame];

    if (self) {

        // Initialization code

    }

    return self;

}

-(id)initWithCoder:(NSCoder* )aDecoder{

    self = [super initWithCoder:aDecoder];

    if (self) {

        //啟動觸控

        self.userInteractionEnabled= YES;

        //設定圖檔

        self.image = [UIImage imageNamed:@"image4.jpg"];

        //加入手勢

        

        /*

        UIPanGestureRecognizer* pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(doMove:)];

        [self addGestureRecognizer:pan];

        */

        UISwipeGestureRecognizer* swipe1 = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(doLeft:)];

        swipe1.direction = UISwipeGestureRecognizerDirectionLeft;

        //要求雙擊

        swipe1.numberOfTouchesRequired = 2;

        [self addGestureRecognizer:swipe1];

        

        UISwipeGestureRecognizer* swipe2 = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(doRight:)];

        //要求雙擊

        swipe2.numberOfTouchesRequired = 2;

        swipe2.direction = UISwipeGestureRecognizerDirectionRight;

        [self addGestureRecognizer:swipe2];

        

    }

    return self;

}

-(void)doLeft:(UISwipeGestureRecognizer*)recognizer{

    CGPoint newPoint = CGPointMake(self.center.x-50, self.center.y);

    self.center = newPoint;

}

-(void)doRight:(UISwipeGestureRecognizer*)recognizer{

    CGPoint newPoint = CGPointMake(self.center.x+50, self.center.y);

    self.center = newPoint;

}

/*

-(void)doMove:(UIPanGestureRecognizer*)recognizer{

    //取得解控點

    CGPoint clickPoint = [recognizer translationInView:self];

    NSLog(@"Move的點是(%.1f,%.1f)",clickPoint.x,clickPoint.y);

    //開始移動

    CGPoint newPoint = CGPointMake(startPoint.x+clickPoint.x, startPoint.y+clickPoint.y);

    self.center = newPoint;

}

*/

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

    //取得觸控點

    CGPoint clickPoint = [[touches anyObject]locationInView:self];

    NSLog(@"觸控點在(%.1f,%.1f)",clickPoint.x,clickPoint.y);

    startPoint = clickPoint;

}

/*

// Only override drawRect: if you perform custom drawing.

// An empty implementation adversely affects performance during animation.

- (void)drawRect:(CGRect)rect

{

    // Drawing code

}

*/

@end

位移手勢辨識

#import <UIKit/UIKit.h>

@interface MyImageView : UIImageView{

    CGPoint startPoint;

}

@end

#import "MyImageView.h"

@implementation MyImageView

- (id)initWithFrame:(CGRect)frame

{

    self = [super initWithFrame:frame];

    if (self) {

        // Initialization code

    }

    return self;

}

-(id)initWithCoder:(NSCoder* )aDecoder{

    self = [super initWithCoder:aDecoder];

    if (self) {

        //啟動觸控

        self.userInteractionEnabled= YES;

        //設定圖檔

        self.image = [UIImage imageNamed:@"image4.jpg"];

        //加入手勢

        UIPanGestureRecognizer* pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(doMove:)];

        [self addGestureRecognizer:pan];

    }

    return self;

}

-(void)doMove:(UIPanGestureRecognizer*)recognizer{

    //取得解控點

    CGPoint clickPoint = [recognizer translationInView:self];

    NSLog(@"Move的點是(%.1f,%.1f)",clickPoint.x,clickPoint.y);

    //開始移動

    CGPoint newPoint = CGPointMake(startPoint.x+clickPoint.x, startPoint.y+clickPoint.y);

    self.center = newPoint;

}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

    //取得觸控點

    CGPoint clickPoint = [[touches anyObject]locationInView:self];

    NSLog(@"觸控點在(%.1f,%.1f)",clickPoint.x,clickPoint.y);

    startPoint = clickPoint;

}

/*

// Only override drawRect: if you perform custom drawing.

// An empty implementation adversely affects performance during animation.

- (void)drawRect:(CGRect)rect

{

    // Drawing code

}

*/

@end