I am trying to make a HTTP request in this way:

```
 NSString *urlString = [NSString stringWithFormat:@"https://api.dropbox.com/1/oauth/request_token"];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:urlString]];
[request setHTTPMethod:@"POST"];

//set headers
NSString *contentType = [NSString stringWithFormat:@"text/xml"];
[request addValue:contentType forHTTPHeaderField: @"Content-Type"];

 oauth_version="1.0"
oauth_signature_method="PLAINTEXT"
oauth_consumer_key="<app-key>"
oauth_signature="<app-secret>&"

//create the body
NSMutableData *postBody = [NSMutableData data];
[postBody appendData:[[NSString stringWithFormat:@"<xml>"] dataUsingEncoding:NSUTF8StringEncoding]];
[postBody appendData:[[NSString stringWithFormat:@"<yourcode/>"] dataUsingEncoding:NSUTF8StringEncoding]];
[postBody appendData:[[NSString stringWithFormat:@"</xml>"] dataUsingEncoding:NSUTF8StringEncoding]];

//post
[request setHTTPBody:postBody];

//get response
NSHTTPURLResponse* urlResponse = nil;  
NSError *error = [[NSError alloc] init];  
NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&urlResponse error:&error];  
NSString *result = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
NSLog(@"Response Code: %d", [urlResponse statusCode]);
if ([urlResponse statusCode] >= 200 && [urlResponse statusCode] < 300) {
    NSLog(@"Response: %@", result);

    //here you get the response

}

```

I am trying to make the request with these headers:

```
Authorization: OAuth oauth_version="1.0", oauth_signature_method="PLAINTEXT", oauth_consumer_key="<app-key>", oauth_signature="<app-secret>&"

```

But I can't understand how to. PLease help!!