iPhone开发中的技巧整理

1、NSCalendar用法

-(NSString *) getWeek:(NSDate *)d

{

NSCalendar *calendar = [[NSCalendar alloc]

initWithCalendarIdentifier:NSGregorianCalendar];

unsigned units = NSYearCalendarUnit | NSMonthCalendarUnit |

NSDayCalendarUnit | NSWeekCalendarUnit;

NSDateComponents *components = [calendar components:units

fromDate:d];

[calendar release];

switch ([components weekday]) {

case1:

return @"Monday"; break;

case2:

return @"Tuesday"; break;

case3:

return @"Wednesday"; break;

case4:

return @"Thursday"; break;

case5:

return @"Friday"; break;

case6:

return @"Saturday"; break;

case7:

return @"Sunday"; break;

default:

return @"NO Week"; break;

}

NSLog(@"%@",components); 

}

 

2、将网络数据读取为字符串

-(NSString *)getDataByURL:(NSString *)url {

return [[NSString alloc] initWithData:[NSData dataWithContentsOfURL: [NSURL URLWithString:[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]] encoding:NSUTF8StringEncoding];

}

 

3、读取⺴络图⽚

-(UIImage *)getImageByURL:(NSString *)url {

return [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL: [NSURL URLWithString:[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]]];

}

 

4、多线程(这种方式,只管建立线程,不管回收线程)

[NSThread detachNewThreadSelector:@selector(scheduleTask) toTarget:self withObject:nil];

-(void)scheduleTask

{

NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

[pool release]; 

}

 

如果有参数,则这么⽤

[NSThread detachNewThreadSelector:@selector(scheduleTask:) toTarget:self withObject:[NSDate date]];

-(void)scheduleTask:(NSDate *)mdate

{

NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

[pool release]; }

 

在线程⾥运⾏主线程⾥的⽅法

[self performSelectorOnMainThread:@selector(moveToMain) withObject:nil waitUntilDone:FALSE];

 

5、⽤户缺省值NSUserDefaults读取:

NSUserDefaults *df = [NSUserDefaults standardUserDefaults];

NSArray *languages = [df objectForKey:@"AppleLanguages"]; 

NSLog(@"all language is %@",languages);

NSLog(@"index is %@",[languages objectAtIndex:0]);

NSLocale *currentLocale = [NSLocale currentLocale];

NSLog(@"language Code is %@",[currentLocale objectForKey:NSLocaleLanguageCode]); 

NSLog(@"Country Code is %@",[currentLocale objectForKey:NSLocaleCountryCode]);

 

6、view之间转换的动态效果设置

SecondViewController *secondViewController = [[SecondViewController alloc] init];

secondViewController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;//⽔水平翻转

[self.navigationController presentModalViewController:secondViewController animated:YES];

[secondViewController release];

 

 

7、UIScrollView 滑动用法: -(void)scrollViewDidScroll:(UIScrollView *)scrollView

{

NSLog(@"正在滑动中。。")

}

//⽤户直接滑动UIScrollView,可以看到滑动条

-(void)scrollViewDidEndDelerating:(UIScrollView *)scrollView {

}

//通过其他控件触发UIScrollView滑动,看不到滑动条

-(void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView {

}

//UIScrollView 设置滑动不超出本⾝身范围

[scrollView setBounces:NO]; 

 

8、iphone的系统目录:

//得到Document:目录

NSArray *paths =

NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentsDirectory = [paths objectAtIndex:0];

//得到temp临时目录

NSString *temPath = NSTemporaryDirectory();

//得到目录上的文件地址

NSString *address = [paths stringByAppendingPathComponent:@"1.rtf"];

 

9、状态栏显⽰示indicator

[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;

 

10、app Icon显示数字:

- (void)applicationDidEnterBackground:(UIApplication *)application

{

 

 [[UIApplication sharedApplication] setApplicationIconBadgeNumber:5];

}

11、sqlite保存地址:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectoryNSUserDomainMask, YES);

NSString *thePath = [paths objectAtIndex:0];

NSString *filePath = [thePath stringByAppendingPathComponent:@"kilometer.sqlite"];

NSString *dbPath = [[[NSBundle mainBundle] resourcePathstringByAppendingPathComponent:@"kilometer2.sqlite"];

 

12、键盘弹出隐藏,textfield变位置

_tspasswordTF = [[UITextField alloc] initWithFrame: CGRectMake(100,

150, 260, 30)];

_tspasswordTF.backgroundColor = [UIColor redColor];

_tspasswordTF.tag = 2;

/*

Use this method to release shared resources, save user data,

_tspasswordTF.delegate = self;

[self.window addSubview: _tspasswordTF];

 

- (void)textFieldDidBeginEditing:(UITextField *)textField {

[self animateTextField: textField up: YES]; 

}

 

- (BOOL)textFieldShouldReturn:(UITextField *)textField {

[self animateTextField: textField up: NO]; 

[textField resignFirstResponder];

return YES;

}

- (void) animateTextField: (UITextField*) textField up: (BOOL) up {

const int movementDistance = 80; 

// tweak as needed 

const float movementDuration = 0.3f; 

// tweak as needed

int movement = (up ? -movementDistance : movementDistance);

[UIView beginAnimations: nil context: nil]; [UIView setAnimationBeginsFromCurrentState: YES]; [UIView setAnimationDuration: movementDuration];

self.window.frame = CGRectOffset(self.window.frame, 0, movement);

[UIView commitAnimations]; 

}

 

13、获取图片的尺⼨

CGImageRef img = [imageView.image CGImage]; 

NSLog(@"%d",CGImageGetWidth(img)); 

NSLog(@"%d",CGImageGetHeight(img));

 

14、AlertView,ActionSheet的cancelButton点击事件:

- (void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex: (NSInteger)buttonIndex; // before animation and hiding view

{

  NSLog(@"cancel alertView... buttonindex = %d",buttonIndex); //当⽤用户按下Cancel按钮

  if (buttonIndex == [alertView cancelButtonIndex]){

  exit(0); 

  }

}

- (void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex

{

NSLog(@"%s %d button = %d cancel actionSheet.....",__FUNCTION__,__LINE__, buttonIndex);

//当⽤用户按下Cancel按钮

  if (buttonIndex == [actionSheet cancelButtonIndex]) {

  exit(0);

  } 

}

15、给window设置全局背景图片

self.window.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@""]];

 

16、tabcontroller随意切换tabbar

-(void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController 

或者

-(BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController

或者

_tabBarController.selectedIndex = tabIndex;

 

17、计算字符串⻓度:

CGFloat w = [title sizeWithFont:[UIFont fontWithName:@"Arial" size: 18]].width;

 

18、计算点到线段的最短距离

根据结果坐标使⽤用CLLocation类的函数计算实际距离。 double

x1, y1, x2, y2, x3, y3;

double px =x2 -x1;

double py = y2 -y1;

double som = px *px + py *py;

double u =((x3 - x1)*px +(y3 - y1)*py)/som; if(u > 1)

{ u=1; }

if (u < 0) { u =0;

}

//the closest point

double x = x1 + u *px; double y = y1 + u * py; double dx = x - x3; double dy = y - y3;

double dist = sqrt(dx*dx + dy*dy);

 

19、UISearchBar背景透明 

在使用UISearchBar时,将背景⾊设定为clearColor,或者将translucent设为YES,都

不能使背景透明,经过一番研究,发现了一种超级简单和实用的⽅法:

[[searchbar.subviews objectAtIndex:0] removeFromSuperview];

背景完全消除了,只剩下搜索框本身了。

 

20、图像与缓存 :

UIImageView *wallpaper = [[UIImageView alloc] initWithImage: [UIImage imageNamed:@"icon.png"]]; // 会缓存图片

UIImageView *wallpaper = [[UIImageView alloc] initWithImage: [UIImage imageWithContentsOfFile:@"icon.png"]]; // 不会缓存图⽚片

 

21、iphone对视图层的操作

// 将textView的边框设置为圆角

_textView.layer.cornerRadius = 8;

_textView.layer.masksToBounds = YES;

//给textView添加一个有色边框

_textView.layer.borderWidth = 5;

_textView.layer.borderColor = [[UIColor colorWithRed:0.52 green:0.09

blue:0.07 alpha:1] CGColor]; 

//textView添加背景图片

_textView.layer.contents = (id)[UIImage imageNamed:@"31"].CGImage;

 

22、关闭当前应用

[[UIApplication sharedApplication] performSelector:@selector(terminateWithSuccess)];

 

23、给iPhone程序添加欢迎界面

1、将你需要的欢迎界面的图片,存成Default.png 

[NSThread sleepForTimeInterval:10.0]; 这样欢迎页面就停留10秒后消失了。

 

24、NSString NSDate转换

NSString* myString= @"testing";

NSData* data=[myString dataUsingEncoding: [NSString defaultCStringEncodi ng]];

NSString* aStr =

[[NSString alloc] initWithData:aData encoding:NSASCIIStringEncoding];

 

25、UIWebView中的dataDetectorTypes 

如果你希望在浏览页面时,页面上的电话号码显示成链接形式,点击电话号码就拨打电话,这时你就需要用到dataDetectorTypes了。

 

NSURL *url = [NSURL URLWithString:@"http://2015.iteye.com"]; 

NSURLRequest *requestObj = [NSURLRequest requestWithURL:url]; webView.dataDetectorTypes = UIDataDetectorTypePhoneNumber; 

[webView loadRequest:requestObj];

 

26、打开苹果电脑浏览器的代码

如您想在 Mac 软件中集成一键打开浏览器功能,可以使用以下代码

 

[[NSWorkspace sharedWorkspace] openURLs: urls withAppBundleIdentifier:@"com.apple.Safari"

options: NSWorkspaceLaunchDefault additionalEventParamDescriptor: NULL launchIdentifiers: NULL];

 

27、设置StatusBar以及NavigationBar的样式

[UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleBlackOpaque; self.navigationController.navigationBar.barStyle = UIBarStyleBlack;

 

28、隐藏Status Bar 你可能知道一个简易的方法,那就是在程序的viewDidLoad中加入以下代码:

 

[UIApplication sharedApplication].statusBarHidden = YES; 

此法可以隐藏状态条,但问题在于,状态条所占空间依然无法为程序所用。

本篇介绍的方法依然简单,但更为奏效。通过简单的3个步骤,在plist中加入一 个键值来实现。

1. 点击程序的Info.plist

2. 右键点击任意一处,选择Add Row

3. 加入的新键值,命名为UIStatusBarHidden或者Status bar is initially hidden,然后选上这一项。

 

29、产生随机数的最佳方案

arc4random()会返回一个整型数,因此,返回1至100的随机数可以这样写: 

arc4random()%100 + 1;

 

30、string 和char转换 

NSString *cocoaString = [[NSString alloc] initWithString:@"MyString"];

const char *myCstring = [cocoaString cString];

const char *cString = "Hello";

NSString *cocoString = [[NSString alloc] initWithCString:cString];

 

31、用UIWebView在当前程序中打开网页 如果URL中带中文的话,必须将URL中的中文转成URL形式的才行。

NSString *query = [NSString stringWithFormat:@"http://www.baidu.com?q=苹 果"];

NSString *strUrl = [query stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSURL *url = [NSURL URLWithString:strUrl];

NSURLRequest *requestObj = [NSURLRequest requestWithURL:url]; 

[webView loadRequest:requestObj];

 

32、阻止ios设备锁屏 

[[UIApplication sharedApplication] setIdleTimerDisabled:YES];

或 

[UIApplication sharedApplication].idleTimerDisabled = YES; 

 

33、一条命令卸载Xcode和 iPhone SDK

sudo /Developer/Library/uninstall-devtools --mode=all

 

34、获取按钮的title

-(void)btnPressed:(id)sender {

NSString *title = [sender titleForState:UIControlStateNormal]; 

NSString *newText = [[NSString alloc] initWithFormat:@"%@",title]; 

label.text = newText;

[newText release]; 

}

 

35、NSDate to NSString

NSString *dateStr = [[NSString alloc] initWithFormat:@"%@", date];

或者

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];

[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

NSString *strDate = [dateFormatter stringFromDate:[NSDate date]];

NSLog(@"%@", strDate); 

[dateFormatter release];

 

36、图片由小到大缓慢显示的效果

UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 0, 0)];

[imageView setImage:[UIImage imageNamed:@"4.jpg"]]; 

self.ANImageView = imageView;

[self.view addSubview:imageView];

[imageView release];

CGContextRef context = UIGraphicsGetCurrentContext(); 

[UIView beginAnimations:nil context:context];

[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut]; 

[UIView setAnimationDuration:2.5];

CGImageRef img = [self.ANImageView.image CGImage];

[ANImageView setFrame:CGRectMake(0, 0, CGImageGetWidth(img), CGImageGetHeight(img))];

[UIView commitAnimations]; 

NSLog(@"%lu",CGImageGetWidth(img));

NSLog(@"%lu",CGImageGetHeight(img));

 

37、数字转字符串

NSString *newText = [[NSString alloc] initWithFormat:@"%d",number]; 

numberlabel.text = newText;

[newText release];

 

38、随机函数arc4random() 的使用.

在iPhone中,RAND_MAX是0x7fffffff (2147483647),而arc4random()返回的 最大值则是 0x100000000 (4294967296),从而有更好的精度。使用 arc4random()还不需要生成随机种子,因为第一次调用的时候就会自动生成。

如:

arc4random() 来获取0到100之间浮点数

#define ARC4RANDOM_MAX 0x100000000

double val = floorf(((double)arc4random() / ARC4RANDOM_MAX) * 100.0f);

1. self.view.backgroundColor = [UIColor colorWithHue: arc4random() % 2 55 / 255

2. 3. 4.

saturation: arc4random() % 2 brightness: arc4random() % 2

alpha: 1.0];

 

39、改变键盘颜色的实现

iPhone和iPod touch的键盘颜色其实是可以通过代码更改的,这样能更匹配 App的界面风格,下面是改变iPhone键盘颜⾊色的代码。

-(void)textFieldDidBeginEditing:(UITextField *)textField {

NSArray *ws = [[UIApplication sharedApplication] windows]; 

for(UIView *w in ws)

{

NSArray *vs = [w subviews]; 

for(UIView *v in vs)

{

 

if([[NSString stringWithUTF8String:object_getClassName(v)] isEqualToString:@"UIPeripheralHostView"])

{

v.backgroundColor = [UIColor blueColor];

} }

} }

55 / 255 55 / 255

_textField.keyboardAppearance = UIKeyboardAppearanceAlert;//有这个设置属性 才起作用

 

40、iPhone上实现Default.png动画 添加一张和Default.png⼀一样的图片,对这个图片进行动画,从而实现Default动画的渐变消 失的效果。

UIImageView *splashView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];

splashView.image = [UIImage imageNamed:@"Default.png"];

[self.window addSubview:splashView];

[self.window bringSubviewToFront:splashView];

[UIView beginAnimations:nil context:nil];

[UIView setAnimationDuration:2.0];

[UIView setAnimationTransition:UIViewAnimationTransitionNone forView:

self.window cache:YES];

[UIView setAnimationDelegate:self];

[UIView setAnimationDidStopSelector:@selector(startupAnimationDone:finished:cont ext:)];

splashView.alpha = 0.0;

splashView.frame = CGRectMake(-60, -85, 440, 635);

 [UIView commitAnimations];

 

41、将EGO主题色添加到xcode中 打开终端,执行以下命令

Shell代码

1. mkdir -p ~/Library/Application\ Support/Xcode/Color\ Themes; 2. cd ~/Library/Application\ Support/Xcode/Color\ Themes;

3. curl -O http://developers.enormego.com/assets/egotheme/

EGO.xccolortheme

然后,重启Xcode,选择Preferences > Fonts & Colors,最后从Color Theme 中选择EGO即可。

 

42、将图片保存到图片库中

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

UITouch *touch = [touches anyObject]; 

if ([touch tapCount]== 1)

{

UIImageWriteToSavedPhotosAlbum([ANImageView image], nil, nil, nil);

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"存储照⽚片 message:@"您已将照⽚存于图片库中,打开照片程序即可查" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];

 

[alert show];

[alert release];

} 

}

 

43、读取plist文件

//取得文件路径

NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"文件

名" ofType:@"plist"];

//读取到一个字典

NSDictionary *dictionary = [[NSDictionary alloc] initWithContentsOfFile:plistPath];

//读取到一个数组

NSArray *array = [[NSArray alloc] initWithContentsOfFile:plistPath];

 

44、使用#pragma mark 加上这样的标识后,在导航条上会显示源文件上方法列表,这样就可对功能相关的方法进行分隔,方便查看了。

设置UITabBarController默认的启动Item //a tabBar

UITabBarController *tabBarController = [[UITabBarController alloc] init];

NSArray *controllers = [NSArray arrayWithObjects: nav1, nav2, nav3, nav4, nil];

tabBarController.viewControllers = controllers; tabBarController.selectedViewController = nav2;

 

45、NSUserDefaults的使用

NSUserDefaults *store = [NSUserDefaults standardUserDefaults]; 

NSUInteger selectedIndex = 1;

[store setInteger:selectedIndex forKey:@"selectedIndex"];

if ([store valueForKey:@"selectedIndex"] != nil) {

NSInteger index = [store integerForKey:@"selectedIndex"]; 

NSLog(@"⽤用户已经设置的selectedIndex的值是:%d", index);

} 

else { 

NSLog(@"请设置默认的值");

}

 

46、更改Xcode的缺省公司名 在终端中执行以下命令:

defaults write com.apple.Xcode PBXCustomTemplateMacroDefiniti ons '{"ORGANIZATIONNAME" = "COMPANY";}'

 

47、设置uiView,成圆角矩形 画个圆角的矩形没啥难的,有两种方法:

1 。直接修改view的样式,系统提供好的了:

view.layer.cornerRadius = 6;

view.layer.masksToBounds = YES; 用layer做就可以了,十分简单。这个需要倒库 QuartzCore.framework;

2. 在view 里面画圆角矩形 CGFloat radius = 20.0;

CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSetRGBStrokeColor(context, 1.0, 1.0, 1.0, 1);

CGFloat minx = CGRectGetMinX(rect), midx = CGRectGetMidX(rect), maxx =

CGRectGetMaxX(rect);

CGFloat miny = CGRectGetMinY(rect), midy = CGRectGetMidY(rect), maxy =

CGRectGetMaxY(rect);

CGContextMoveToPoint(context, minx, midy); CGContextAddArcToPoint(context, minx, miny, midx, miny, radius); CGContextAddArcToPoint(context, maxx, miny, maxx, midy, radius); CGContextAddArcToPoint(context, maxx, maxy, midx, maxy, radius); CGContextAddArcToPoint(context, minx, maxy, minx, midy, radius); CGContextClosePath(context);

CGContextDrawPath(context, kCGPathFill);

用画笔的方法,在drawRect里面做。

 

48、画图时图片倒转解决方法

CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSaveGState(context);

CGContextTranslateCTM(context, 0, self.bounds.size.height); CGContextScaleCTM(context, 1, -1);

drawImage = [UIImage imageNamed:@"12.jpg"];

CGImageRef image = CGImageRetain(drawImage.CGImage);

CGContextDrawImage(context, CGRectMake(30.0, 200, 450, 695), image); CGContextRestoreGState(context);

 

49、Nsstring 自适应文本宽高度

CGSize feelSize = [feeling sizeWithFont:[UIFont systemFontOfSize:12]

constrainedToSize:CGSizeMake(190, 200)];

float feelHeight = feelSize.height;

 

50、用HTTP协议,获取www.baidu.com网站的HTML数据:

[NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://www.baidu.com"]];

 

51、viewDidLoad中设置按钮图案

UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];

button.frame = CGRectMake(0, 0, 60, 30);

[button addTarget:self action:@selector(buttonAction:) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:button];

 

UIImage *buttonImageNormal = [UIImage imageNamed:@"huifu-001.png"];

UIImage *stretchableButtonImageNormal = [buttonImageNormal

stretchableImageWithLeftCapWidth:12 topCapHeight:0];

 [button setBackgroundImage:stretchableButtonImageNormal forState:UIControlStateNormal]; UIImage *buttonImagePressed = [UIImage imageNamed:@"qyanbuhuifu-001.png"];

UIImage *stretchableButtonImagePressed = [buttonImagePressed stretchableImageWithLeftCapWidth:12 topCapHeight:0]; 

[button setBackgroundImage:stretchableButtonImagePressed forState:UIControlStateHighlighted];

52、键盘上的return键改成Done: textField.returnKeyType = UIReturnKeyDone;

 

53、textfield设置成为密码框: [textField_pwd setSecureTextEntry:YES];

 

54、收回键盘: [textField resignFirstResponder]; 或者 [textfield addTarget:self action:@selector(textFieldDone:) forControlEvents:UIControlEventEditin gDidEndOnExit];

55、振动:

#import<AudioToolbox/AudioToolbox.h> //需加头文件

方法一: AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);

方法二: AudioServicesPlaySystemSound(kSystemSoundID_Vibrate); 当设备不支持方法一函数时,起蜂鸣作用, 而方法二支持所有设备

 

56、用Cocoa删除文件:

NSFileManager *defaultManager = [NSFileManager defaultManager]; 

[defaultManager removeFileAtPath: tildeFilename  handler: nil];

 

57、UIView透明渐变与移动效果:

//动画配制开始

[UIView beginAnimations:@"animation" context:nil]; [UIView setAnimationDuration:2.5];

//图片上升动画

CGRect rect = imgView.frame ;

rect.origin.y = 30;

imgView.frame = rect;

//半透明度渐变动画

imgView.alpha = 0;

//提交动画

[UIView commitAnimations];

 

58、在UIView的drawRect方法内,用Quartz2D API绘制一个像素宽的水平直线: 

-(void)drawRect:(CGRect)rect{

//获取图形上下文

CGContextRef context = UIGraphicsGetCurrentContext(); //设置图形上下文的路径绘制颜色 CGContextSetStrokeColorWithColor(context, [UIColor

whiteColor].CGColor); //取消防锯齿

CGContextSetAllowsAntialiasing(context, NO); //添加线

CGContextMoveToPoint(context, 50, 50); 

CGContextAddLineToPoint(context, 100, 50); //绘制

CGContextDrawPath(context, kCGPathStroke); }

 

59、用UIWebView加载: www.baidu.com

UIWebView *web = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];

[web loadRequest:[NSURLRequest requestWithURL: [NSURL URLWithString:@"http://www.baidu.com"]]];

[self.view addSubview:web]; 

[web release];

 

60、利用UIImageView实现动画:

- (void)viewDidLoad {

[super viewDidLoad];

UIImageView *fishAni=[[UIImageView alloc] initWithFrame: [[UIScreen mainScreen] bounds]];

[self.view addSubview:fishAni];

 [fishAni release];

//设置动画帧

fishAni.animationImages=[NSArray arrayWithObjects: [UIImage imageNamed:@"1.jpg"],

[UIImage imageNamed:@"2.jpg"],

[UIImage imageNamed:@"3.jpg"],

[UIImage imageNamed:@"4.jpg"],

[UIImage imageNamed:@"5.jpg"],nil ];

//设置动画总时间 fishAni.animationDuration=1.0;

//设置重复次数,0表示不重复 fishAni.animationRepeatCount=0;

//开始动画

[fishAni startAnimating]; }

 

61、用NSTimer做一个定时器,每隔1秒执行一次 pressedDone; 

-(IBAction)clickBtn:(id)sender{

NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(printHello) userInfo:nil repeats:YES]; 

[timer fire];

 }

 

62、利用苹果机里的相机进行录像:

-(void) choosePhotoBySourceType: (UIImagePickerControllerCameraCaptureMode) sourceType {

m_imagePickerController = [[[UIImagePickerController alloc] init] autorelease];

m_imagePickerController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;

m_imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera; m_imagePickerController.cameraDevice =UIImagePickerControllerCameraDeviceFront; 

//m_imagePickerController.cameraCaptureMode =UIImagePickerControllerCameraCaptureModeVideo;

NSArray *sourceTypes = [UIImagePickerController availableMediaTypesForSourceType:m_imagePickerController.sourceType];

if ([sourceTypes containsObject:(NSString *)kUTTypeMovie ]) {

m_imagePickerController.mediaTypes= [NSArray arrayWithObjects: (NSString *)kUTTypeMovie,(NSString *)kUTTypeImage,nil];

}

// m_imagePickerController.cameraCaptureMode = sourceType; //m_imagePickerController.mediaTypes //imagePickerController.allowsEditing = YES;

[self presentModalViewController: m_imagePickerController animated:YES];

 }

 

-(void) takePhoto {

if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])

{

[self choosePhotoBySourceType:nil];

} }

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.

- (void)viewDidLoad {

[super viewDidLoad];

UIButton *takePhoto = [UIButton

buttonWithType:UIButtonTypeRoundedRect];

[takePhoto setTitle:@"录像" forState:UIControlStateNormal];

 [takePhoto addTarget:self action:@selector(takePhoto) forControlEvents:UIControlEventTouchUpInside]; 

takePhoto.frame = CGRectMake(50,100,100,30); [self.view addSubview:takePhoto];

}

63、App中调用 iPhone的home + 电源键截屏功能 

// 前置声明是消除警告

CGImageRef UIGetScreenImage();

CGImageRef img = UIGetScreenImage();

UIImage* scImage=[UIImage imageWithCGImage:img]; UIImageWriteToSavedPhotosAlbum(scImage, nil, nil, nil);

 

64、切割图片的方法

//切割图片

UIImage *image = [UIImage imageNamed:@"7.jpg"];

//设置需要截取的⼤大⼩小

CGRect rect = CGRectMake(20, 50, 280, 200);

//转换

CGImageRef imageRef = image.CGImage;

//截取函数

CGImageRef imageRefs = CGImageCreateWithImageInRect(imageRef, rect); 

//生成uIImage

UIImage *newImage = [[UIImage alloc] initWithCGImage:imageRefs]; 

//添加到imageView中

imageView = [[UIImageView alloc] initWithImage:newImage]; 

imageView.frame = rect;

 

65、如何屏蔽父view的touch事件

-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event

{

CGMutablePathRef path = CGPathCreateMutable(); CGPathMoveToPoint(path,NULL,0,0);

CGRect rect = CGRectMake(0, 100, 320, 40); CGPathAddRect(path, NULL, rect); if(CGPathContainsPoint(path, NULL, point, NO)) {

[self.superview touchesBegan:nil withEvent:nil]; }

CGPathRelease(path);

return self; 

}

 

66、用户按home键推送通知

UIApplication *app = [UIApplication sharedApplication]; 

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(pressHome:) name:UIApplicationDidEnterBackgroundNotification object:app];

-(void)pressHome:(NSNotification *)notification {

NSLog(@"pressHome..."); 

}

 

67、在UIImageView中旋转图像:

float rotateAngle = M_PI; //M_PI为一角度

CGAffineTransform transform =CGAffineTransformMakeRotation(rotateA ngle);

imageView.transform = transform;

 

68、隐藏状态栏:

方法一, [UIApplication sharedApplication] setStatusBarHidden:YES animated:NO]; 

方法二, 在应用程序的Info.plist 文件中将 UIStatusBarHidden 设置为YES; 

 

69、构建多个可拖动视图:

@interface DragView: UIImageView{

CGPoint startLocation;

NSString *whichFlower; }

@property (nonatomic ,retain)NSString *whichFlower; @end

@implementation DragView

@synthesize whichFlower;

 

- (void) touchesBegan:(NSSet *)touches withEvent: (UIEvent *)event{ CGPoint pt = [[touhes anyObject ] locationInView:self]; startLocation = pt;

[[self superview] bringSubviewToFront:self];

}

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

CGPoint pt = [[touches anyObject] locatonInView:self]; CGRect frame = [self frame];

frame.origin.x += pt.x – startLocation.x;

frame.origin.y += pt.y - startLocation.y;

[self setFrame:frame]; }

@end

@interface TestController :UIViewController{

UIView *contentView;

}

@end

@implementation TestController

#define MAXFLOWERS 16

CGPoint randomPoint(){ 

return CGPointMake(random()%6 , random()96);

}

- (void)loadView{

CGRect apprect = [[UIScreen mainScreen] applicationFrame]; 

contentView = [[UIView alloc] initWithFrame :apprect]; 

contentView.backgroundColor = [UIColor blackColor]; 

self.view = contentView;

[contentView release];

for(int i=0 ; i<MAXFLOWERS; i++){

CGRect dragRect = CGRectMake(0.0f ,0.0f, 64.0f ,64.0f); 

dragRect.origin = randomPoint();

DragView *dragger = [[DragView alloc] initWithFrame:dragRect];

 [dragger setUserInteractionEnabled: YES];

NSString *whichFlower = [[NSArray arrayWithObjects:@”blueFlower.png”,@”pinkFlower.png”,nil] objectAtIndex: ( random() %2)];

[dragger setImage:[UIImage imageNamed:whichFlower]]; 

[contentView addSubview :dragger];

[dragger release];

} }

- (void)dealloc{

 [contentView release];

[super dealloc]; 

}

@end

 

70、iPhone中加入dylib库

加入dylib库时,必须在info中加入头文件路径。/usr/include/库名(不要后缀)

 

71、iPhone iPad 中App名字如何支持多语言和显示自定义名字

建立InfoPlist.strings,本地化此文件,然后在文件内添加: CFBundleDisplayName = "xxxxxxxxxxx"; //

这样应⽤用程序就能显示成设置的名字“xxxxxxxxxxx”. 

 

 

72、在数字键盘上添加button:

//定义一个消息中心

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil]; 

//addObserver:注册一个观察员 name:消息名称

- (void)keyboardWillShow:(NSNotification *)note {

// create custom button

UIButton *doneButton = [UIButton buttonWithType:UIButtonTypeCustom];

 doneButton.frame = CGRectMake(0, 163, 106, 53);

[doneButton setImage:[UIImage imageNamed:@"5.png"]

forState:UIControlStateNormal];

[doneButton addTarget:self action:@selector(addRadixPoint) forControlEvents:UIControlEventTouchUpInside];

// locate keyboard view

UIWindow* tempWindow = [[[UIApplication sharedApplication] windows] objectAtIndex:1];

//返回应用程序window

UIView* keyboard;

for(int i=0; i<[tempWindow.subviews count]; i++) 

//遍历window上的所有 subview

{

keyboard = [tempWindow.subviews objectAtIndex:i];

// keyboard view found; 

add the custom button to it 

if([[keyboard description] hasPrefix:@"<UIKeyboard"] == YES) 

[keyboard addSubview:doneButton];

} 

}

73、去掉iPhone应用图标上的弧形高光 有时候我们的应用程序不需要在图标上加上默认的高光,可以在你的应用的 Info.plist中加入:

Icon already includes gloss effects YES

 

74、实现修改navigation的back按钮 

self.navigationItem.backBarButtonItem =

[[[UIBarButtonItem alloc] initWithTitle: NSLocalizedStringFromTable (@"返回", @"System", nil) style:UIBarButtonItemStyleBordered target:nil action:nil] autorelease];

 

75、给图片加上阴影

UIImageView*pageContenterImageView = [[UIImageView alloc]initWithImage: [UIImage imageNamed:@"onePageApple.png"]];

//添加边框

CALayer*layer = [pageContenterImageView layer];

layer.borderColor= [[UIColor whiteColor]CGColor];

layer.borderWidth=0.0f;

//添加四个边阴影

pageContenterImageView.layer.shadowColor= [UIColor blackColor].CGColor;

pageContenterImageView.layer.shadowOffset=CGSizeMake(0,0); pageContenterImageView.layer.shadowOpacity=0.5; pageContenterImageView.layer.shadowRadius=5.0; 阴影渲染会严重消耗内存 ,导致程序咔叽.

/*阴影效果*/

//添加边框

CALayer*layer = [self.pageContenter layer];

layer.borderColor= [[UIColorwhiteColor]CGColor];

layer.borderWidth=0.0f;

//添加四个边阴影

self.pageContenter.layer.shadowColor= [UIColorblackColor].CGColor;//阴影颜色

self.pageContenter.layer.shadowOffset=CGSizeMake(0,0);//阴影偏移 self.pageContenter.layer.shadowOpacity=0.5;//阴影不透明度 self.pageContenter.layer.shadowRadius=5.0;//阴影半径

⼆二、给视图加上阴影

UIView * content=[[UIView alloc] initWithFrame:CGRectMake(100, 250, 503, 500)];

content.backgroundColor=[UIColor orangeColor];

//content.layer.shadowOffset=10;

content.layer.shadowOffset = CGSizeMake(5, 3); content.layer.shadowOpacity = 0.6; content.layer.shadowColor = [UIColor blackColor].CGColor;

[self.window addSubview:content]; 

 

76、UIView有一个属性,clipsTobounds 默认情况下是NO, 如果,我们想要view2把超出的那部份隐藏起来的话,就得改变它的父视图也 就view1的clipsTobounds属性值。

view1.clipsTobounds = YES;

使用objective-c 建立UUID UUID是128位的值,它可以保证唯一性。通常,它是由机器本身网卡的MAC地

址和当前系统时间来生成的。 UUID是由中划线连接而成的字符串。例如:0A326293-BCDD-4788-8F2D-

C4D8E53C108B

在声明文件中声明一个方法:

#import <UIKit/UIKit.h>

@interface UUIDViewController : UIViewController { }

- (NSString *) createUUID;

@end

对应的实现文件中实现该方法:

- (NSString *) createUUID {

CFUUIDRef uuidObject = CFUUIDCreate(kCFAllocatorDefault);

NSString *uuidStr = (NSString *)CFUUIDCreateString(kCFAllocatorDefault, uuidObject);

CFRelease(uuidObject);

return uuidStr; }

 

77、iPhone iPad中横屏显示代码 

1、强制横屏

[application setStatusBarOrientation:UIInterfaceOrientationLandscapeRight animated:NO];

2、在infolist⾥里⾯面加了Supported interface orientations这⼀一项,增加之后添加四个item就是 ipad的四个⽅方向

item0 UIInterfaceOrientationLandscapeLeft

item1 UIInterfaceOrientationLandscapeRight 这表明只⽀支持横屏显⽰示 经常让人混淆迷惑的问题 - 数组和其他集合类

 

78、当一个对象被添加到一个array, dictionary, 或者 set等这样的集合类型中的时候,集合会retain它。 对应 的,当集合类被release的时候,它会发送对应的release消息给包含在其中的对象。 因此,如果你想建立一 个包含一堆number的数组,你可以像下面示例中的几个方法来做

NSMutableArray *array; int i;

// ...

for (i = 0; i < 10; i++) {

NSNumber *n = [NSNumber numberWithInt: i];

[array addObject: n]; }

在这种情况下, 我们不需要retain这些number,因为array将替我们这么做。 NSMutableArray *array;

int i;

// ...

for (i = 0; i < 10; i++) {

NSNumber *n = [[NSNumber alloc] initWithInt: i];

 [array addObject: n];

[n release];

}

在这个例子中,因为你使用了-alloc去建立了一个number,所以你必须显式的-release它,以保证retain count的平衡。因为将number加入数组的时候,已经retain它了,所以数组中的number变量不会被release

 

79、UIView动画停止调用方法遇到的问题

在实现UIView的动画的时候,并且使⽤用UIView来重复调⽤用它结束的回调时候要 注意以下⽅方法中的finished参数

-(void)animationDidStop:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context

{

if([finishied boolValue] == YES)

//一定要判断这句话,要不在程序中当多个View刷新的时候,就可能出现动画异常的现象 {

//执行想要的动作 }

}

 

80、判断在UIViewController中,viewWillDisappear的时候是push还是 pop出来

- (void)viewWillDisappear:(BOOL)animated {

NSArray *viewControllers = self.navigationController.viewControllers; if (viewControllers.count > 1 && [viewControllers

objectAtIndex:viewControllers.count-2] == self) {

// View is disappearing because a new view controller was pushed onto the

stack

NSLog(@"New view controller was pushed");

} else if ([viewControllers indexOfObject:self] == NSNotFound) { // View is disappearing because it was popped from the stack NSLog(@"View controller was popped");

} }

 

81、连接字符串小技巧

NSString *string1 = @"abc / cde";

NSString *string2 = @"abc" @"cde";

NSString *string3 = @"abc" "cde";

NSLog( @"string1 is %@" , string1 ); 

NSLog( @"string2 is %@" , string2 ); NSLog( @"string3 is %@" , string3 ); 

打印结果如下:

string1 is abc cde string2 is abccde

 

82、随文字大小label自适应

label=[[UILabel alloc] initWithFrame:CGRectMake(50, 23, 175, 33)];

label.backgroundColor = [UIColor purpleColor];

[label setFont:[UIFont fontWithName:@"Helvetica" size:30.0]]; 

[label setNumberOfLines:0];

//[myLable setBackgroundColor:[UIColor clearColor]]; [self.window addSubview:label];

NSString *text = @"this is ok";

UIFont *font = [UIFont fontWithName:@"Helvetica" size:30.0];

CGSize size = [text sizeWithFont: font constrainedToSize: CGSizeMake(175.0f, 2000.0f) lineBreakMode: UILineBreakModeWordWrap];

CGRect rect= label.frame; rect.size = size;

[label setFrame: rect]; [label setText: text];

 

83、UILabel字体加粗

//加粗

lb.font = [UIFont fontWithName:@"Helvetica-Bold" size:20]; //加粗并且倾斜

lb.font = [UIFont fontWithName:@"Helvetica-BoldOblique" size:20];

 

84、为IOS应用组件添加圆角的方法 具体的实现是使用QuartzCore库,下面我具体的描述一下实现过程:

• 首先创建一个项目,名字叫:ipad_webwiew

• 利⽤用Interface Builder添加⼀一个UIWebView,然后和相应的代码相关联 • 添加QuartzCore.framework

代码实现: 头⽂文件:

#import <UIKit/UIKit.h>

#import <QuartzCore/QuartzCore.h>

@interface ipad_webwiewViewController : UIViewController {

IBOutlet UIWebView *myWebView; UIView *myView;

}

@property (nonatomic,retain) UIWebView *myWebView; @end

代码实现:

- (void)viewDidLoad {

[super viewDidLoad]; //给图层添加背景图⽚片: //myView.layer.contents = (id)[UIImage

imageNamed:@"view_BG.png"].CGImage; //将图层的边框设置为圆脚

myWebView.layer.cornerRadius = 8; myWebView.layer.masksToBounds = YES; //给图层添加⼀一个有⾊色边框

myWebView.layer.borderWidth = 5; myWebView.layer.borderColor = [[UIColor colorWithRed:0.52

green:0.09 blue:0.07 alpha:1] CGColor]; }

 

85、实现UIToolBar的自动消失 

-(void)showBar

{

! [UIView beginAnimations:nil context:nil];

! [UIView setAnimationDuration:0.40];

! (_toolBar.alpha == 0.0) ? (_toolBar.alpha = 1.0) : (_toolBar.alpha = 0.0);

! [UIView commitAnimations];

}

- (void)viewDidAppear:(BOOL)animated {

[NSObject cancelPreviousPerformRequestsWithTarget: self];

[self performSelector: @selector(delayHideBars) withObject: nil afterDelay: 3.0];

}

- (void)delayHideBars { [self showBar];

}

 

86、自定义UINavigationItem.rightBarButtonItem

UISegmentedControl *segmentedControl = [[UISegmentedControl alloc] initWithItems:[NSArray arrayWithObjects:@"remote",@"mouse",@"text",nil]];

[segmentedControl insertSegmentWithImage:[UIImage imageNamed:@"home_a.png"] atIndex:0 animated:YES];

[segmentedControl insertSegmentWithImage:[UIImage imageNamed:@"myletv_a.png"] atIndex:1 animated:YES];

segmentedControl.segmentedControlStyle = UISegmentedControlStyleBar; segmentedControl.frame = CGRectMake(0, 0, 200, 30); 

[segmentedControl setMomentary:YES];

[segmentedControl addTarget:self action:@selector(segmentAction:)

forControlEvents:UIControlEventValueChanged];

UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:segmentedControl];

self.navigationItem.rightBarButtonItem = barButtonItem; 

[segmentedControl release];

UINavigationController直接返回到根viewController

 [self.navigationController popToRootViewControllerAnimated:YES];

想要从第五层直接返回到第二层或第三层,用索引的形式

[self.navigationController popToViewController: [self.navigationController.viewControllers objectAtIndex: ([self.navigationController.viewControllers count] - 2)] animated:YES];

 

87、键盘监听事件

#ifdef __IPHONE_5_0

float version = [[[UIDevice currentDevice] systemVersion] floatValue];

if (version >= 5.0)

{

[[NSNotificationCenter defaultCenter] addObserver:self

selector:@selector(keyboardWillShow:) name:UIKeyboardWillChangeFrameNotification object:nil];

}

#endif

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];

-(void)keyboardWillShow:(NSNotification *)notification {

NSValue *value = [[notification userInfo] objectForKey:@"UIKeyboardFrameEndUserInfoKey"];

CGRect keyboardRect = [value CGRectValue]; NSLog(@"value %@ %f",value,keyboardRect.size.height); [UIView beginAnimations:nil context:nil];

[UIView setAnimationDuration:0.25];

keyboardHeight = keyboardRect.size.height; self.view.frame = CGRectMake(0, -(251 - (480 - 64 -

keyboardHeight)), self.view.frame.size.width, self.view.frame.size.height);

[UIView commitAnimations]; }

 

88、 ios6.0强制横屏的方法:

在appDelegate里调用

if (!UIDeviceOrientationIsLandscape([[UIDevice currentDevice] orientation])) {

        [[UIApplication sharedApplication]

setStatusBarOrientation:

UIInterfaceOrientationLandscapeRight animated:NO];

    }