[英]Return Response data from nsurlconnection delegate method
嗨,我正在使用Web服務進行注冊,我制作了一個單獨的類來訪問Web服務並在View類上返回響應。
這是我在Button上的代碼
-(IBAction)placeOrder:(id)sender
{
url = [[NSURL alloc]initWithString:@"http://54.25fdg.239.126/tfl/index.php/service/register"];
NSString *str = [NSString stringWithFormat:@"name=%@&phoneNumber=%@&emailAddress=%@&password=%@&addressLine1=%@&addressLine2=%@&city=%@&pincode=%@&landmark=%@&specialInstruction=%@",txtUserName.text,txtPhone.text,txtEmail.text,txtPassword.text,addressLine1Tf.text,addressLine2Tf.text,cityTf.text,pinCodeTf.text,landMarkTf.text,specialInstrTv.text];
WebServices *webservice = [[WebServices alloc]init];
[webservice getDataFromService:url data:str];
responseDictionary = [webservice returnResponseData];
}
調用getDataFromService
方法后,它將調用returnRespnoseData
方法。 然后,它調用從getDataFromService
調用的連接方法。 所以我從returnResponseData
得到了nil
響應。 誰能告訴我如何管理它,或者如何將didfinishloading
方法的響應返回給主視圖類? 在webservice.m
-(void)getDataFromService:(NSURL *)url data:(NSString *)parameterString
{
NSData *postData = [parameterString dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:@"%lu",(unsigned long)[postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:url];
[request setHTTPMethod:@"POST"];
[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[request setHTTPBody:postData];
NSURLConnection *conn = [[NSURLConnection alloc]initWithRequest:request delegate:self];
[conn start];
}
在連接上一個方法時,我在字典中得到了響應,如jsonDec
。
-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSError* error ;
_jsonDec = [NSJSONSerialization JSONObjectWithData:_responseData options:NSJSONReadingAllowFragments error:&error];
}
返回jsonDec到View類
-(NSDictionary *)returnResponseData
{
return _jsonDec;
}
問題是您要在取回數據之前調用returnResponseData。
假設您要取回數據,您將看到日志以意外的順序返回。
-(IBAction)placeOrder:(id)sender
{
NSLog(@"Button Pressed");
url = [[NSURL alloc]initWithString:@"http://54.254.239.126/tfl/index.php/service/register"];
NSString *str = [NSString stringWithFormat:@"name=%@&phoneNumber=%@&emailAddress=%@&password=%@&addressLine1=%@&addressLine2=%@&city=%@&pincode=%@&landmark=%@&specialInstruction=%@",txtUserName.text,txtPhone.text,txtEmail.text,txtPassword.text,addressLine1Tf.text,addressLine2Tf.text,cityTf.text,pinCodeTf.text,landMarkTf.text,specialInstrTv.text];
WebServices *webservice = [[WebServices alloc]init];
[webservice getDataFromService:url data:str];
responseDictionary = [webservice returnResponseData];
}
-(void)getDataFromService:(NSURL *)url data:(NSString *)parameterString
{
NSLog(@"Getting Data");
NSData *postData = [parameterString dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:@"%lu",(unsigned long)[postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:url];
[request setHTTPMethod:@"POST"];
[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[request setHTTPBody:postData];
NSURLConnection *conn = [[NSURLConnection alloc]initWithRequest:request delegate:self];
[conn start];
}
-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSLog(@"Finished getting data");
NSError* error ;
_jsonDec = [NSJSONSerialization JSONObjectWithData:_responseData options:NSJSONReadingAllowFragments error:&error];
}
-(NSDictionary *)returnResponseData
{
NSLog(@"Returning data");
return _jsonDec;
}
您將需要等到didFinishConnection被調用,然后才能使用_jsonDec進行任何操作。 另外,如果您要更新UI,則可能要確保您位於MainThread上。 “如果”我的內存正確,則didFinishConnection可能不會返回主線程。
為確保應用程序在響應到達后將jsondata返回給viewclass,請在您的類的.h文件中定義一個塊:
typedef void(^getDataBlock)(id jsonObject);
然后,您的getDataFromService方法可能如下所示:
-(void)getDataFromService:(NSURL *)url data:(NSString *)parameterString getDataBlock:(getDataBlock)returnBlock{
NSLog(@"Getting Data");
NSData *postData = [parameterString dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:@"%lu",(unsigned long)[postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:url];
[request setHTTPMethod:@"POST"];
[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[request setHTTPBody:postData];
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
NSError *error = [[NSError alloc] init];
id jsonDec = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];
returnBlock(jsonDec);
}];
}
在您的視圖類中,您現在可以執行以下操作:
-(void)test{
//Insert the right name for your class where you do the request and insert the right values
[backendClass getDataFromService:[NSURL URLWithString:@"www.google.de"] data:@"blablabla" getDataBlock:^(id jsonObject) {
//Make sure you're on the mainthread for UI-updates
dispatch_async(dispatch_get_main_queue(), ^{
self.titleLabel.text = [jsonObject objectForKey:@"title"];
});
}];
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.