All I want is to change every time the NSString townLocation.
Because I take data from an API and I don't want to create different API for different location. Also I know that the "+" that I put on the link is not correct and there is not such think in Objective C but I want to make you understand what I want.
NSString*townLocation;
NSData* data = [NSData dataWithContentsOfURL:[NSURL URLWithString:#"http://api.openweathermap.org/data/2.5/find?q="+townLocation+"&units=metric"]];
How I must do it ? Im sure you understand that I'm new at Objective C
Thank you
You only need to look into the most basic NSString documentation to find a method that will do that, stringWithFormat:.
NSString *urlString = [NSString stringWithFormat:#"http://api.openweathermap.org/data/2.5/find?q=%#&units=metric", townLocation];
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]];
If you're new at Objective-C, a good place to find information like this is to simply search the internet or the iOS Developer Library for the class in question (in this case, NSString) to find a myriad of resources at your disposal. Another doc to check would be Formatting String Objects, which is linked in the stringWithFormat: section of the iOS Developer Library, to find more info about formatting strings.
Related
If I take a browser and type http://www.youtube.com/get_video_info?video_id=$id&el=embedded&ps=default&eurl=&gl=US&hl=en into it, I get a bunch of text describing video with ID $id in a form of a file, that gets downloaded by a browser. The file contains a large string that is unique every time the request is performed.
Now, I need to gain access to that giant string inside iOS app.
Could you please tell me where to start digging? UIWebViews? Or maybe there's a simple solution?
Thanks in advance.
NSURL *url = [NSURL URLWithString:#"https://www.youtube.com/get_video_info?video_id=$id&el=embedded&ps=default&eurl=&gl=US&hl=en"];
NSData *data = [NSData dataWithContentsOfURL:url];
NSString *idString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
I have one string. Now I wanted to split this string. For static separation I know the code but I don’t code for dynamic value.
my string is
NSString *str = #"https://graph.facebook.com/v2.5/181054825200000/feed?fields=created_time,message,picture,full_picture,comments.limit%280%29.summary%28true%29,likes.limit%280%29.summary%28true%29&limit=5&format=json&access_token=CAALjFrE5mNYBAOg1EDiUrsE2kr1kIRrLIv7g4OweSMvHso2exB5Dttshn7dgOlW24ZCXSnDZAWiV6xMUKXedTXUhiHpdmZBPCGzD1orFlrLRP2gaBZCbZBZBnjUHewF9hZBmJKxtiwVzpw9gnnQXk5Hfx0ZBM2ksAUzkSWR5feaNMbf3UUmUpJlxeh0gKdDrzWBvIJRPy0xGqL0ZAMFsRhyCZCTX42l1sZAceZB0VCeDZB95mrAZDZD&until=1456345291&__paging_token=enc_AdCKD3tSYMoZB3MCKaJkYnbVmBgUyY2tBceGDD2G1hqxRDiQKZCsSbmvWZASLvlCMf0BVzq2uZAScSWp7ZAavZB2d72BIHJISefk09noRuv9gA5b5hFwZDZD";
but i don’t how to show any value dynamically .(for e.g. until (in string))
please help me for this issue.
Thank You.
If you are parsing a URL you should really use NSURLComponents. It makes breaking a URL into the different parts much easier, and the code is tested and verified by Apple.
For separate string by a separator you can use this.
NSString *url = #"<url>";
NSArray *array = [url componentsSeparatedByString:#"<seperator string>"];
NSLog(#"%#", array);
But for URL parsing ,As per Duncan's answer, yes it is good to parse a URL using NSURLComponents. By using this class you can get any desired part of an URL.
So I'm working on a small example on how to make a service call to a specific web service. I'm using the openweathermap.org web service. The link to this service is the following:
http://api.openweathermap.org/data/2.5/weather?q=London,uk
According to this link, I can search weather by city name. So I'm able to retrieve and NSLog the JSON data with the following code:
NSString *urlString = [NSString stringWithFormat:WXFORECAST, LOCATION];
NSURL *url = [NSURL URLWithString:urlString];
NSData *data = [NSData dataWithContentsOfURL:url];
NSDictionary *json = [NSJSONSerialization
JSONObjectWithData:data options:kNilOptions error:nil];
NSLog(#"%#", json);
This does the bare minimum and retrieves the service. Now I would like to get my specific city instead of London.
If not, I would like to get JUST THE WEATHER part instead of getting the wind speed, and all that other garbage.
Here is the link for details on the API:
http://openweathermap.org/API#weather
Under that link there's a section that says this:
Restriction output:
To limit number of listed cities please setup cnt parameter api.openweathermap.org/data/2.5/find?lat=57&lon=-2.15&cnt=3
I believe this might be what I'm looking for but I don't know exactly how to use it...
All help is appreciated, thanks.
The API is accessed with a URL, try playing with this in your browser:
http://api.openweathermap.org/data/2.5/weather?q=New+York,us
See how I have a plus sign between "New" and "York"? That's to make sure the URL is valid, because they don't allow for spaces.
You have to figure out a way to get the URL you want in your variable. In your code, it's creating the URL using a format string stored in WXFORECAST. So, update that.
I don't have time to read through all of how that API works, but it's possible that you can't request that it gives you less information. But there's nothing stopping you from taking only what you need from it. It's all in that JSON dictionary, if you wanted to get the temperature your code might look like this.
NSArray *list = json[#"list"];
NSDictionary *london = list[0];
NSDictionary *main = london[#"main"];
NSString *temp = main[#"temp"];
Only a short question here, I would like to know the best place to put my registration code for the user that I get back from the server. I am encrypting it as seen here.
//encrypting
NSString* strToEncrypt =NewPINField.text
NSString* theKey = #\"KeyKeyKeyKey\";
NSData* dataToEncrypt = [strToEncrypt dataUsingEncoding: NSUTF8StringEncoding];
NSData *encryptedData = [dataToEncrypt EncryptWithKey: theKey];
NSLog(#\"Encrypted data: %#\", encryptedData);
//decrypting
NSData* encryptedData = (NSData*)[profileData objectForKey:#\"PIN\"];
NSString* theKey = #\"KeyKeyKeyKey\"; //notice this is the same as above. It MUST be
NSData *decData = [encryptedData DecryptWithKey: theKey ];
currentPIN = [NSString stringWithUTF8String:[decData bytes]];
NSLog(#\"Decrypted pin: %#\", currentPIN);
The only other specification is to hide it / put it somewhere no know would think to look.
I need to save state so it needs to be some sort of plist, I was just wondering if there is a way to hide it a little better than just adding it straight to my plist file.
what would you do?
Any help would be greatly appreciated.
If you need to securely store data, I would highly recommend using the keychain. There is a tutorial on creating a basic keychain app here: http://www.raywenderlich.com/6475/basic-security-in-ios-5-tutorial-part-1
You can safely store data in the keychain without worrying about encrypting it first, since that is handled by the OS. But you can if you want to.
When implementing security, never try to hide things where someone won't look: http://en.wikipedia.org/wiki/Security_through_obscurity
What is the easiest and fastest code to do a conversion between NSData and a base64 string? I've read a bunch of solutions at SO and mostly they involve in adding another class etc. I found a great solution here but it's too complex.
Scroll down to the Conclusion section on the page you linked and download the provided NSData+Base64 files. Its the best solution I have seen so far and is incredibly easy to use. If you can learn anything about Cocoa, you can learn to use that project.
Example
NSString *originalString = [NSString stringWithFormat:#"test"];
NSData *data = [NSData dataFromBase64String:originalString];
NSLog([data base64EncodedString]);
The above will print out the original string after converting it to base64 and back to a normal unencoded string.
As of iOS 7, NSData now directly provides this functionality with the new methods -base64EncodedDataWithOptions: and -base64EncodedStringWithOptions:. (The options let you specify that the string is/should be line-wrapped, the better to deal with email, and user-facing displays.)
You don't need any custom implementation. Creating base64 from NSData is shown in other answers. There is opposite direction. From Base64 string to NSData:
NSString *base64Encoded = #"some base64 string";
NSData *nsdataFromBase64String = [[NSData alloc] initWithBase64EncodedString:base64Encoded options:0];
I ended up using this same class as provided by SUDZC
implementation was easy first I did an import
#import "NSData+Base64.h"
then I was able to call my data.
NSData *data = [[NSData alloc] initWithData:[NSData dataWithBase64EncodedString:strData]];
Be aware that there are more Base64 formats.
For example JWTs use a URL safe format.
Or you may take a look to the (quite new) CryptoCompatibility sample project, I think there is a wrapper class for base64 operation. It is a MacOS sample but it uses the library libresolve.dylib with I think is available on iOS too (is see it at least here in iOS7).