iOS 17个常用代码整理

转自 http://blog.csdn.net/jinglijun/article/details/8351883

1.判断邮箱格式是否正确的代码：      //利用正则表达式验证      -(BOOL)isValidateEmail:(NSString *)email      {          NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";          NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES%@",emailRegex];          return [emailTest evaluateWithObject:email];      }      2.图片压缩      用法：UIImage *yourImage= [self imageWithImageSimple:image scaledToSize:CGSizeMake(210.0, 210.0)];      //压缩图片      - (UIImage*)imageWithImageSimple:(UIImage*)image scaledToSize:(CGSize)newSize      {          // Create a graphics image context          UIGraphicsBeginImageContext(newSize);          // Tell the old image to draw in this newcontext, with the desired          // new size          [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];          // Get the new image from the context          UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();          // End the context          UIGraphicsEndImageContext();          // Return the new image.          return newImage;      }      3.亲测可用的图片上传代码      - (IBAction)uploadButton:(id)sender {          UIImage *image = [UIImage imageNamed:@"1.jpg"]; //图片名          NSData *imageData = UIImageJPEGRepresentation(image,0.5);//压缩比例          NSLog(@"字节数:%i",[imageData length]);          // post url          NSString *urlString = @"http://192.168.1.113:8090/text/UploadServlet";          //服务器地址          // setting up the request object now          NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init] ;          [request setURL:[NSURL URLWithString:urlString]];          [request setHTTPMethod:@"POST"];          //          NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"];          NSString *contentType = [NSString stringWithFormat:@"multipart/form-data;boundary=%@",boundary];          [request addValue:contentType forHTTPHeaderField: @"Content-Type"];          //          NSMutableData *body = [NSMutableData data];          [body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];          [body appendData:[[NSString stringWithString:@"Content-Disposition:form-data; name=\"userfile\"; filename=\"2.png\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; //上传上去的图片名字          [body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];          [body appendData:[NSData dataWithData:imageData]];          [body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];          [request setHTTPBody:body];          // NSLog(@"1-body:%@",body);          NSLog(@"2-request:%@",request);          NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];          NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];          NSLog(@"3-测试输出：%@",returnString);       4.给imageView加载图片          UIImage *myImage = [UIImage imageNamed:@"1.jpg"];          [imageView setImage:myImage];          [self.view addSubview:imageView];       5.对图库的操作          选择相册：          UIImagePickerControllerSourceTypesourceType=UIImagePickerControllerSourceTypeCamera;          if (![UIImagePickerControllerisSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {              sourceType=UIImagePickerControllerSourceTypePhotoLibrary;          }          UIImagePickerController * picker = [[UIImagePickerControlleralloc]init];          picker.delegate = self;          picker.allowsEditing=YES;          picker.sourceType=sourceType;          [self presentModalViewController:picker animated:YES];          选择完毕：          -(void)imagePickerController:(UIImagePickerController*)pickerdidFinishPickingMediaWithInfo:(NSDictionary *)info          {              [picker dismissModalViewControllerAnimated:YES];              UIImage * image=[info objectForKey:UIImagePickerControllerEditedImage];              [self performSelector:@selector(selectPic:) withObject:imageafterDelay:0.1];          }          -(void)selectPic:(UIImage*)image          {              NSLog(@"image%@",image);              imageView = [[UIImageView alloc] initWithImage:image];              imageView.frame = CGRectMake(0, 0, image.size.width, image.size.height);              [self.viewaddSubview:imageView];              [self performSelectorInBackground:@selector(detect:) withObject:nil];          }          detect为自己定义的方法，编辑选取照片后要实现的效果          取消选择：          -(void)imagePickerControllerDIdCancel:(UIImagePickerController*)picker          {              [picker dismissModalViewControllerAnimated:YES];          }        6.跳到下个View          nextWebView = [[WEBViewController alloc] initWithNibName:@"WEBViewController" bundle:nil];          [self presentModalViewController:nextWebView animated:YES];                              //创建一个UIBarButtonItem右边按钮          UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithTitle:@"右边" style:UIBarButtonItemStyleDone target:self action:@selector(clickRightButton)];          [self.navigationItem setRightBarButtonItem:rightButton];          设置navigationBar隐藏          self.navigationController.navigationBarHidden = YES;//          iOS开发之UIlabel多行文字自动换行 （自动折行）          UIView *footerView = [[UIView alloc]initWithFrame:CGRectMake(10, 100, 300, 180)];          UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(10, 100, 300, 150)];          label.text = @"Hello world! Hello world!Hello world! Hello world! Hello world! Hello world! Hello world! Hello world!Hello world! Hello world! Hello world! Hello world! Hello world! Helloworld!";          //背景颜色为红色          label.backgroundColor = [UIColor redColor];          //设置字体颜色为白色          label.textColor = [UIColor whiteColor];          //文字居中显示          label.textAlignment = UITextAlignmentCenter;          //自动折行设置          label.lineBreakMode = UILineBreakModeWordWrap;          label.numberOfLines = 0;        7.代码生成button          CGRect frame = CGRectMake(0, 400, 72.0, 37.0);          UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];          button.frame = frame;          [button setTitle:@"新添加的按钮" forState: UIControlStateNormal];          button.backgroundColor = [UIColor clearColor];          button.tag = 2000;          [button addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];          [self.view addSubview:button];        8.让某个控件在View的中心位置显示：          （某个控件，比如label，View）label.center = self.view.center;        9.好看的文字处理          以tableView中cell的textLabel为例子：          cell.backgroundColor = [UIColorscrollViewTexturedBackgroundColor];          //设置文字的字体          cell.textLabel.font = [UIFont fontWithName:@"AmericanTypewriter" size:100.0f];          //设置文字的颜色          cell.textLabel.textColor = [UIColor orangeColor];          //设置文字的背景颜色          cell.textLabel.shadowColor = [UIColor whiteColor];          //设置文字的显示位置          cell.textLabel.textAlignment = UITextAlignmentCenter;        10. ———————-隐藏Status Bar—————————–          读者可能知道一个简易的方法,那就是在程序的viewDidLoad中加入          [[UIApplication sharedApplication]setStatusBarHidden:YES animated:NO];        11 更改AlertView背景                    UIAlertView *theAlert = [[[UIAlertViewalloc] initWithTitle:@"Atention"                                                             message: @"I'm a Chinese!"                                                            delegate:nil                                                   cancelButtonTitle:@"Cancel"                                                   otherButtonTitles:@"Okay",nil] autorelease];          [theAlert show];          UIImage *theImage = [UIImageimageNamed:@"loveChina.png"];          theImage = [theImage stretchableImageWithLeftCapWidth:0topCapHeight:0];          CGSize theSize = [theAlert frame].size;          UIGraphicsBeginImageContext(theSize);          [theImage drawInRect:CGRectMake(5, 5, theSize.width-10, theSize.height-20)];//这个地方的大小要自己调整，以适应alertview的背景颜色的大小。          theImage = UIGraphicsGetImageFromCurrentImageContext();          UIGraphicsEndImageContext();          theAlert.layer.contents = (id)[theImage CGImage];        12. 键盘透明          textField.keyboardAppearance = UIKeyboardAppearanceAlert;                  13.状态栏的网络活动风火轮是否旋转          [UIApplication sharedApplication].networkActivityIndicatorVisible，默认值是NO。                  14.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);        15.更改cell选中的背景          UIView *myview = [[UIView alloc] init];          myview.frame = CGRectMake(0, 0, 320, 47);          myview.backgroundColor = [UIColorcolorWithPatternImage:[UIImage imageNamed:@"0006.png"]];          cell.selectedBackgroundView = myview;        16.显示图像:          CGRect myImageRect = CGRectMake(0.0f, 0.0f, 320.0f, 109.0f);          UIImageView *myImage = [[UIImageView alloc] initWithFrame:myImageRect];          [myImage setImage:[UIImage imageNamed:@"myImage.png"]];          myImage.opaque = YES; //opaque是否透明          [self.view addSubview:myImage];        17.能让图片适应框的大小（没有确认）          NSString*imagePath = [[NSBundle mainBundle] pathForResource:@"XcodeCrash"ofType:@"png"];          UIImage *image = [[UIImage alloc]initWithContentsOfFile:imagePath];          UIImage *newImage= [image transformWidth:80.f height:240.f];          UIImageView *imageView = [[UIImageView alloc]initWithImage:newImage];          [newImagerelease];          [image release];          [self.view addSubview:imageView];        18.实现点击图片进行跳转的代码：生成一个带有背景图片的button，给button绑定想要的事件！          UIButton *imgButton=[[UIButton alloc]initWithFrame:CGRectMake(0, 0, 120, 120)];          [imgButton setBackgroundImage:(UIImage *)[self.imgArray objectAtIndex:indexPath.row] forState:UIControlStateNormal];          imgButton.tag=[indexPath row];          [imgButton addTarget:self action:@selector(buttonClick:) forControlEvents:UIControlEventTouchUpInside];      

1、获取全局的Delegate对象，这样我们可以调用这个对象里的方法和变量：

[(MyAppDelegate*)[[UIApplication sharedApplication] delegate] MyMethodOrMyVariable];

2、获得程序的主Bundle：

NSBundle *bundle = [NSBundle mainBundle];

Bundle可以理解成一种文件夹，其内容遵循特定的框架。

Main Bundle一种主要用途是使用程序中的资源文件，如图片、声音、plst文件等。

NSURL *plistURL = [bundle URLForResource:@"plistFile" withExtension:@"plist"];

上面的代码获得plistFile.plist文件的路径。

3、在程序中播放声音：

首先在程序添加AudioToolbox：

其次，在有播放声音方法的.m方法添加#import：

#import<AudioToolbox/AudioToolbox.h>

接下来，播放声音的代码如下：

NSString *path = [[NSBundle mainBundle] pathForResource:@"soundFileName" ofType:@"wav"]; 

SystemSoundID soundID; 

AudioServicesCreateSystemSoundID ((__bridge CFURLRef)[NSURL fileURLWithPath:path], &soundID); 

AudioServicesPlaySystemSound (soundID); 

4、设置和获取类中属性值：

[self setValue: 变量值 forKey: 变量名];

[self valueForKey: 变量名];

5、让某一方法在未来某段时间之后执行：

[self performSelector:@selector(方法名) withObject:nil afterDelay:延迟时间（s）]; 

6、获得设备版本号：

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

7、捕捉程序关闭或者进入后台事件：

UIApplication *app = [UIApplication sharedApplication];

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationWillResignActive:) name:UIApplicationWillResignActiveNotification object:app];

applicationWillResignActive:这个方法中添加想要的操作

8、查看设备支持的字体：

for (NSString *family in [UIFont familyNames]) {

    NSLog(@"%@", family);

    for (NSString *font in [UIFont fontNamesForFamilyName:family]) {

        NSLog(@"\t%@", font);

    }

}

9、为UIImageView添加单击事件：

imageView.userInteractionEnabled = YES;

UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(yourHandlingCode:)];

[imageView addGestureRecognizer:singleTap];

10、添加多语言支持： 比如Image Picker这样的组件，它上面的按钮的文字是随着设备语言环境的改变而改变的，但是要先在工程添加语言：

11、使程序支持iTunes这样的设备，比如可以使用PC端的工具往程序的Documents中拖放文件。

12、页面切换效果设置：

controller.modalTransitionStyle = UIModalTransitionStyleCoverVertical;

[self presentModalViewController:controller animated:YES];

可供使用的效果：

UIModalTransitionStyleCoverVertical

UIModalTransitionStyleFlipHorizontal

UIModalTransitionStyleCrossDissolve

UIModalTransitionStylePartialCurl

恢复之前的页面：

[self dismissModalViewControllerAnimated:YES];