iphone开发常用代码2

- (NSString *)URLEncodedString:(NSString *)string{
    NSString *result = (NSString *)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,
                                                       (CFStringRef)string,NULL,CFSTR("!*'();:@&=+$,/?%#[]"),kCFStringEncodingUTF8);
    [result autorelease];
    return result;
}

//生成nonce
- (NSString *)generateNonce{
    CFUUIDRef theUUID = CFUUIDCreate(NULL);
    CFStringRef string = CFUUIDCreateString(NULL, theUUID);
    NSMakeCollectable(theUUID);
    return [(NSString *)string stringByReplacingOccurrencesOfString:@"-" withString:@""];

    //return (NSString *)string;
}

//生成Timestamp
- (NSString *)generateTimestamp{
    return [[NSString stringWithFormat:@"%d", time(NULL)] retain];
}

iPhone键盘改变颜色
只有这2种数字键盘才有效果：UIKeyboardTypeNumberPad，UIKeyboardTypePhonePad
keyboardAppearance ＝ UIKeyboardAppearanceAlert
代码如下：
 

1.    NSArray *ws = [[UIApplication sharedApplication] windows];
2.     for(UIView *w in ws){
3.         NSArray *vs = [w subviews];
4.         for(UIView *v in vs){
5.             if([[NSString stringWithUTF8String:object_getClassName(v)] isEqualToString:@"UIKeyboard"]){
6.                 v.backgroundColor = [UIColor redColor];
7.             }
8.         }
9.     }

从一个界面push到下一界面左上角返回按钮文字设置

在父viewController中如下设置：
    UIBarButtonItem *backbutton = [[UIBarButtonItem alloc]init];

    backbutton.title = @"返回列表";
    self.navigationItem.backBarButtonItem = backbutton;
    [backbutton release];

navigationbar的back键触发其他事件
UIButton *back =[[UIButton alloc] initWithFrame:CGRectMake(200, 25, 63, 30)];
[back addTarget:self act

ion:@selector(reloadRowData:) forControlEvents:UIControlEventTouchUpInside]; [back setImage:[UIImage imageNamed:@"返回按钮.png"] forState:UIControlStateNormal]; UIBarButtonItem *backButtonItem = [[UIBarButtonItem alloc] initWithCustomView:back]; self.navigationItem.leftBarButtonItem = loginButtonItem [back release]; [backButtonItem release]; 防止屏幕暗掉锁屏 [[UIApplication sharedApplication] setIdleTimerDisabled:YES]; 将图片从左到右翻页效果显示         UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 0, 470)];     [imageView setImage:[UIImage imageNamed:@"Bg.jpg"]];     self.myImageView =imageView;     [self.view addSubview:imageView];     [imageView release];     CGContextRef context = UIGraphicsGetCurrentContext();     [UIView beginAnimations:nil context:context];     [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];     [UIView setAnimationDuration:0.5];     [myImageView setFrame:CGRectMake(0, 0, 310, 470)];        [UIView commitAnimations]; 让覆盖在下面层的视图接受触摸事件 searchImage.exclusiveTouch = YES;//第一层 searchImage.userInteractionEnabled = NO; myMapView.exclusiveTouch = NO;//第二层 myMapView.userInteractionEnabled = YES; View的缩放 NSValue *touchPointValue = [[NSValue valueWithCGPoint:CGPointMake(100,100)] retain]; [UIView beginAnimations:nil context:touchPointValue]; transform = CGAffineTransformMakeScale(0.1,0.21); firstPieceView.transform = transform; [UIView commitAnimations];    代码循环添加按钮，其他空间也可以用类似方法添加 - (void)viewDidLoad {     [super viewDidLoad];     for(int i = 0; i < 5; i++){         CGRect frame;         Btn[i] = [[UIButton buttonWithType:UIButtonTypeCustom] retain];         [Btn[i] setImage:[UIImage imageNamed:@"Button.png"] forState:UIControlStateNormal];//设置按钮图片         frame.size.width = 55;//设置按钮坐标及大小         frame.size.height = 84;         frame.origin.x = (i%5)*57+5;         frame.origin.y = 10;         [Btn[i] setFrame:frame];         [Btn[i] setBackgroundColor:[UIColor clearColor]]; 内容来自泠云天天在线         [Btn[i] addTarget:self action:@selector(btnPressed:) forControlEvents:UIControlEventTouchUpInside];         [self.view addSubview:Btn[i]];         [Btn[i] release];     } } //响应按钮事件 -(void)btnPressed:(id)sender{     for(int i = 0; i < 5;i++){         if([sender isEqual:Btn[i]]){             NSLog(@"Btn[%d]:",i);         }     } } 去除nsstring中的空格，table 以及newline，nextline NSCharacterSet *whitespace = [NSCharacterSet whitespaceAndNewlineCharacterSet]; NSString *username = [mUsernameField stringValue]; username = [username stringByTrimmingCharactersInSet:whitespace]; UIImagePickerController 用UIImagePickerController选择、显示图片或视频，主要注意UIImagePickerController几个属性的设置 一：UI 显示样式，显示的格式确定 1：sourceType @property(nonatomic) UIImagePickerControllerSourceType sourceType enum { UIImagePickerControllerSourceTypePhotoLibrary, 本文来自泠云天天在线 UIImagePickerControllerSourceTypeCamera, UIImagePickerControllerSourceTypeSavedPhotosAlbum }; typedef NSUInteger UIImagePickerControllerSourceType; sourceType用来确定用户界面显示的样式： 共三种格式（模拟器上的效果图） UIImagePickerControllerSourceTypePhotoLibrary, UIImagePickerControllerSourceTypeCamera, UIImagePickerControllerSourceTypeSavedPhotosAlbum 为了区分是否支持视频格式，一般要用到下面这个函数，以便确定mediaTypes。 + (BOOL)isSourceTypeAvailable:(UIImagePickerControllerSourceType)sourceType 2:   mediaTypes @property(nonatomic,copy) NSArray *mediaTypes mediaTypes用来确定再picker里显示那些类型的多媒体文件，图片？视频？ + (NSArray *)availableMediaTypesForSourceType:(UIImagePickerControllerSourceType)sourceType 二：选取动作处理 UIImagePickerControllerDelegate 通过代理来完成用户在选中图片，或者choose视频时的处理方式： 共有三个可选的代理方法 – imagePickerController:didFinishPickingMediaWithInfo:  – imagePickerControllerDidCancel:  – imagePickerController:didFinishPickingImage:editingInfo:   Deprecated in iPhone OS 3.0 - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info info中包括选取的照片，视频的主要信息 NSString *const UIImagePickerControllerMediaType;         选取的类型 public.image  public.movie NSString *const UIImagePickerControllerOriginalImage;    修改前的UIImage object. NSString *const UIImagePickerControllerEditedImage;      修改后的UIImage object. NSString *const UIImagePickerControllerCropRect; 原始图片的尺寸NSValue object containing a CGRect data type NSString *const UIImagePickerControllerMediaURL;          视频在文件系统中 的 NSURL地址 保存视频主要时通过获取其NSURL 然后转换成NSData 实例代码如下： - (void) pickImage: (id) sender { 本文来自泠云天天在线 UIImagePickerController *ipc = [[UIImagePickerController alloc] init]; copyright lyttzx.com         if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]){ lyttzx.com      ipc.sourceType =  UIImagePickerControllerSourceTypePhotoLibrary;       ipc.mediaTypes =[UIImagePickerController availableMediaTypesForSourceType:ipc.sourceType];           }  ipc.delegate = self; ipc.allowsImageEditing = NO; [self presentModalViewController:ipc animated:YES]; }   - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{ 内容来自泠云天天在线 NSString *mediaType = [info objectForKey:UIImagePickerControllerMediaType]; 泠云工作室 if ([mediaType isEqualToString:@"public.image"]){ // UIImage *selectedImage = [info objectForKey:UIImagePickerControllerOriginalImage]; UIImage *image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];     NSLog(@"found an image"); [UIImageJPEGRepresentation(image, 1.0f) writeToFile:[self findUniqueSavePath] atomically:YES];     SETIMAGE(image); lyttzx.com CFShow([[NSFileManager defaultManager] directoryContentsAtPath:[NSHomeDirectory() stringByAppendingString:@"/Documents"]]); } else if ([mediaType isEqualToString:@"public.movie"]){   NSURL *videoURL = [info objectForKey:UIImagePickerControllerMediaURL]; NSLog(@"found a video"); copyright lyttzx.com         NSData *webData = [NSData dataWithContentsOfURL:videoURL]; //NSData *video = [[NSString alloc] initWithContentsOfURL:videoURL]; [webData writeToFile:[self findUniqueMoviePath] atomically:YES]; CFShow([[NSFileManager defaultManager] directoryContentsAtPath:[NSHomeDirectory() stringByAppendingString:@"/Documents"]]); 本文来自泠云天天在线 // NSLog(videoURL); } [picker dismissModalViewControllerAnimated:YES]; } 内容来自泠云天天在线 UITextInputTraits属性  autocapitalizationType            设置键盘自动大小写的属性     UITextAutocapitalizationTypeNone autocorrectionType  property  设置是否有自动修改提示   UITextAutocorrectionTypeNo enablesReturnKeyAutomatically   Boolean值－设置在用户没有输入是returnKey禁用，默认值NO keyboardAppearance  设置键盘显示方式  除了默认模式  还有一个UIKeyboardAppearanceAlert模式 keyboardType               设置键盘类型   UIKeyboardTypePhonePad 等 returnKeyType              设置renturnKey按键上的提示文字     UIReturnKeyGo   UIReturnKeyNext secureTextEntry           BOOL值  －－ 设置是否是密码保护模式输入 如下： 设置登录用的 输入框 UITextField 用户名输入框： m_TF_username = [[UITextField alloc] initWithFrame:my_frame]; m_TF_username.borderStyle = UITextBorderStyleNone; m_TF_username.clearButtonMode = UITextFieldViewModeWhileEditing; m_TF_username.delegate = self; m_TF_username.returnKeyType = UIReturnKeyNext; m_TF_username.autocapitalizationType = UITextAutocapitalizationTypeNone; [m_TF_username becomeFirstResponder]; 密码输入框： m_TF_password = [[UITextField alloc] initWithFrame:my_frame]; m_TF_password.borderStyle = UITextBorderStyleNone; m_TF_password.clearButtonMode = UITextFieldViewModeWhileEditing; m_TF_password.delegate = self; m_TF_password.returnKeyType = UIReturnKeyGo; m_TF_password.secureTextEntry =YES; 键盘透明 textField.keyboardAppearance = UIKeyboardAppearanceAlert; 状态栏的网络活动风火轮是否旋转 [UIApplication sharedApplication].networkActivityIndicatorVisible，默认值是NO。 截取屏幕图片 //创建一个基于位图的图形上下文并指定大小为CGSizeMake(200,400) UIGraphicsBeginImageContext(CGSizeMake(200,400)); //renderInContext 呈现接受者及其子范围到指定的上下文 [self.view.layer renderInContext:UIGraphicsGetCurrentContext()];     //返回一个基于当前图形上下文的图片  UIImage *aImage = UIGraphicsGetImageFromCurrentImageContext();    //移除栈顶的基于当前位图的图形上下文 UIGraphicsEndImageContext(); //以png格式返回指定图片的数据 imageData = UIImagePNGRepresentation(aImage); 更改cell选中的背景     UIView *myview = [[UIView alloc] init];     myview.frame = CGRectMake(0, 0, 320, 47);     myview.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"0006.png"]];     cell.selectedBackgroundView = myview; 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 de(责任编辑：泠云)