I want to be able to pull out the user's 50 most recently played songs, then be able to sort that via artist/album/genre etc. How can I make this happen immediately upon the app's opening and what would be the best way (I'm thinking dictionary?) to bundle this up so I can send it to a server?
Thanks!
MPMediaItemPropertyLastPlayedDate might be what you're looking for. See this related question for how to access the various media item properties.
Your app delegate's applicationDidBecomeActive: method would be an appropriate place to scan on-launch, and an NSDictionary converted to JSON should be suitable serialization format.
Be sure to inform the user before sending their data off to your server, however.
Related
I have a social app, where the user can like photos... So, in order not to wait for fetching the data from the server, I want to store to the device, an array of strings, containing the photos' objectIds.. The question is, considering the user can like thousands of photos, is it good practise to use UserDefaults to achieve that?
EDIT
As pointed out by Eric Aya in the comments, NSUserDefaults aren't loaded automatically into memory when the app launches.
NSUserDefaults are loaded into memory when your application launches If you have a particularly large amount of data stored in NSUserDefaults then the time it takes your app to launch to load NSUserDefaults will be impacted by the amount of IO required to retrieve your data. The intended use case for NSUserDefaults is to store small sets of data such as default user settings.
A Plist may be a better solution (NSUserDefaults is just a Plist, the difference being is it's loaded automatically for you when the app launches). You will still have the same issues with load times when you decide to grab the Plist as you will be loading a file (the Plist) into memory. You will be able to handle this with something like a progress bar or an activity indicator which gives the user a nicer experience. than having to wait longer than usual for an app to open. CoreData is another option (usually intended for more complex data structures than strings, on the flip side it gives you the capability to scale your storage needs very easily if the complexity of your data increases), there's a fairly steep learning curve involved but it's a wonderful feature and is well documented by Apple: https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/CoreData/
I would also recommend storing the data on a server where you could expose it via an API and cache the response using a Plist/CoreData/Whatever you like. This way if your users change devices they will still have access to the same data as it's stored remotely.
Good luck!
In our iPhone app , we offer email templates populated with DB. also user can create their own templates.
Say for example , i have my own templates created over 500 entries to use
here i need to know the possibility on the below things since my client asks me.
If i want to to send my templates stored into my DB to myfriend who uses the same application.( So my friend does not have to create the templets on his own , he can use mine)
Can that user be able to load those template details ( DB information ) into his app? (like posting the db contents to server and the same content can be loaded into his app using link)
I think it cant be done but i would like to know opinions and views to convey this to my superior.
Thanks a lot
This could help: How do I associate file types with an iPhone application?
Okay, well.. It's possible to do what you are trying to do.
You would need to
Serialize the data that's stored in the DB
Figure out a way to send this data to the server/as an attachment in an email over to your friend.
So from that point of view,
Doing the first is pretty simple. If its all just string content, you can serialize it into an XML/JSON. There are a lot of ways out there that converts objects into strings or bytes to send them over the network anywhere you please.
The second needs support from the server. You would need a server that can identify the applications from one another. ie. yours from that of your friend's. It should then be made to handle the serialized content you are planning to send over and then figure out a way to send it to the friend. maybe a push notification? You could possibly look at Urban Airship or some such offering for doing this incase you dont have an existing server.
Or, you can cut yourself all the work and see if your workflow can fit into this
http://www.raywenderlich.com/1980/how-to-import-and-export-app-data-via-email-in-your-ios-app
I am recently making an app which needs to exchange messages between different iOS devices.I decide to use mail to do with the data transfer.And I read a tutorial by Ray( http://www.raywenderlich.com/1948/how-integrate-itunes-file-sharing-with-your-ios-app )
.It tells a way to handle this thing.But my situation is that the data I want to transfer are all stored in the sqlite.I think it's better to convert these data into NSString and than send them.But I have no idea of how to define custom UTI which will specify the specific type,like .myapp which will be sent to the receiver,and how to user can open it and import data in the app.Because I use iOS5,so I can't even follow the steps in the tutorial.By now,i can send email to users with the data,but not with the .myapp attachment.So , can anyone give any advice on how to get the data into .myapp file and how the receiver will get data and import it in the app,specially for iOS5?Great thanks.
I successfully made this work via Email by simply constructing a text file in CSV format (comma separated values) to be attached to the email message. I registered the .csv with my app, added an import handler, and now one can then open the file on the other iOS device running the same app.
However, I found this approach rather clumsy and not very user friendly. Have you considered using the Dropbox API instead? Even better, use the new iCloud interface right built right into the SDK. That seems so much more convenient from the user's perspective.
Another approach could be to send the data to a webservice which informs the receiver by notification (Apple Push Service Notification). Your data is then stored on a central system and can be loaded by the app as soon as the receiver gets the notification and opens the app.
Okay, I want to have an app that takes phone numbers from an online database and displays them in a table view. When the user is not online, I want them to still be able to see the numbers they already got from the database in the table view. If the user manages to go back online, the database updates the view. My question is, is this possible to do and if so, what's the best way to approach it? (bit of a newbie, please help me out)
There are many ways to do what you are asking, depending on the complexity of what you are after.
Could I suggest the following steps (I'm not sure which ones you can do, and which ones you are having trouble with).
Connect to the server and retrieve the list of phone numbers
If the database has a web server front end this might be as simple as sending a get request to the server (see NSURLConnection) and parsing the result. Otherwise you will need to know/tell us what type database you are using.
Store the phone numbers on the device
Use SQLite to store the numbers on the device (See iPhone SQLite Resources)
Check for internet connectivity
Periodically check for internet connectivity, and if a specific time has elapsed since you last polled the server, retry. (See Checking iPhone internet connectivity)
Although you’re probably looking for a native app solution, you can also do this with a web app.
http://diveintohtml5.ep.io/offline.html
I am a new developer iPhone developer, "learning" to be precise. I came across the useful NSUserDefaults (a dictionary in which you can store/restore state even after your application relaunches). Problem with this dictionary will be memory in your case. NSUserDefaults is sort of global to all applications and yours may spoil the show for other innocent applications (like Weather :D ).
To work around this, you can have your application declare a property list file where you store a few numbers (best practise would be the most recent but you can use any selector of choice). Look for an appropriate time in your run loop to store these numbers into your property file and load them when the application starts.
I have created an app which displays information in a organized manner about cultural places.
The information is subject to changes, so I want it to be downloaded from the web. But not everytime. Only once in a while, because information doesn't change often.
What I want to do is, the first time the user opens the application, it downloads all data from the web. For the moment, I parse it from an xml (which is about 100Ko), and I get a NSMutableArray of "CulturalPlace" objects. but it is very slow. And what I would like to do is, to store this data locally (in case the user has an iPod touch an is not on a wifi, or if he is on EDGE and does not want to redownload all). So the user updates data only by clicking an "update button" on the top right of the screen. Otherwise it reads it from disk.
I really don't know what could be the best solution. I thought about Core Data, but I have several Tableview imbricated (Rootviewcontroller > ListofPlacesViewController > PlaceViewController) and I really cannot find good tutorial for a simple use like mine. (the iTunes "TopSongs" sample code seems too complex).
I thought also about not parsing the xml, but instead try an NSURLConnection and get a plist file. But I never managed to read anything from the local file.
So my main question is, should I keep the xml parsing method, or should I use another format to tranfert the data from the web? And what is the best way to store and read data like an NSMutableArray of custom Objects ?
Thanks in advance for your help, sorry for my approximate english.
You could use HTML5' localStorage. It's supported by Chrome and FF on the PC and Safari on Mac OS and iPhone (to the best of my knowledge). It acts like a local database. Bear in mind that if the user selects to clear all cookies (or "private settings"), your storage goes away.
You could opt to store the XML locally, and store in NSUserDefaults the date when last updated - then on app launch you can check to see if you have a new file.
ASIHTTPRequest makes it pretty easy to say "Save the contents of this URL to a file". So you'd always save the XML to a file, and always read from that file or fetch XML if it was not yet there.
In my experience XML is indeed much slower to parse than plist, even though they're technically the same thing. Fortunately, plist's are pretty easy to deal with and the API's take care of all of the archiving and de-archiving.
Once you have your data in memory, it probably wouldn't be too hard to convert it to the much faster plist representation, check out this doc for more info: http://developer.apple.com/iphone/library/documentation/Cocoa/Conceptual/Archiving/Archiving.html
If your app is divided into different pages, you might also consider splitting the file into separate files, and only parsing / de-archiving the information you need when you need it (if you did this on a separate thread and displayed a UIProgressView on the main thread, the delay would probably be barely an issue to the user).