iOS学习笔记26—iPhone开发常识集锦
1.检查是否有这个对象或者方法
responseToSelector:@selector
2.延时异步执行
peformSelector:withObject:afterDelay
3.模拟器路径:
/[user]/Library/Application Support/iPhone Simulator/4.2/Applications/B0E3EC07-F395-408F-9B94-A5B0BAECBC2E/Documents/personal.plist
4.自定义发送notification
发送消息
NSDictionary *info = [[NSDictionaryalloc]initWithObjectsAndKeys:nil,@"ret",nil];
[[NSNotificationCenterdefaultCenter]postNotificationOnMainThreadWithName:@"LoginSuccessful" object:self userInfo:info];
接受消息
[[NSNotificationCenterdefaultCenter]addObserver:self selector:@selector(loginSuccessful:) name:@"LoginSuccessful" object:nil];
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
<补充:移动开发 , IOS ,