What's the most efficient parsing method/technique to store, track and associate the associated Nodes and Refs for Polygons while parsing OpenStreetMap (.osm XML) file formats?
This is asked with an iOS Objective-C mobile environment in mind. Thank you.
If there is no pretty good reason, you should rely on the existing work of others and make use of existing OSM XML/PBF parsers that do also some abstraction for you: https://wiki.openstreetmap.org/wiki/Frameworks
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I'm working on a simple ResearchKit app that has 20 survey questions, or ORKSteps. How do I get the answers from a participant who submits the survey into a database?
My research has found ORKESerializer and SQLite as potential parts of the solution. I'm missing a big picture view of how these things can be integrated into a working solution.
Starting without knowledge of databases or data transfer from Swift, so any basic information would be very helpful.
How do I extract data from ORKResult using Swift?
Where do I extract the data to? Or, what's the standard type of database for a small survey?
ResearchKit doesn't have any out-of-the-box solution for storing your results. Generally, it's the task of the developer to go through the ORKResult hierarchy and either persist the processed results for later access or send them to a remote server.
You have several options here:
Use NSCoding to store the vanilla ORKTaskResult (with their ORKResult children). This way you can recreate the whole ORKTaskResult hierarchy at later time to inspect or process it.
Use ORKESerializer (as you guessed) to serialize ORKResults into the JSON format. ORKESerializer is currently included as part of ORKTest's unit tests, and it's not documented very well. It's possible that it will be moved to ResearchKit proper in the future, but it's completely usable right now. The JSON format is particularly useful if you want to send your results to any remote server of your own.
You can manually iterate through ORKResults and convert them into objects that are suitable for storing, or into database records. As you said, you could persist them using SQLite; or other database of your choice; or Core Data.
To sum up, there's no recommended or standard method for persisting results, it depends on your needs.
You can also have a look at the official open sourced RK apps. I think they make use of the AppCore library (which sits on top of the ResearchKit) to store the task results (and also use the Sage Bridge to send the results to Sage's servers). But that may be overboard if your needs are simpler.
I suggest that you run the sample ORKCatalog app and then inspect the ORKTaskResult hierarchy (you can do that within the app itself). You'll get an idea of how the result hierarchy looks.
I do not have experience with the Research Kit but as a database you could use sqlite. stephencelis has made a great wrapper for swift which you can use.
Im using a strategy where I'm saving images and pdfs as NSData in the respective managed objects where they belong. I'm having a problem syncing with Ensembles that the pdf doesn't always carry over from one device to another. Now I'm not sure if this is due to some flaws in my code or if it's not a good way of syncing chunks of data like this. Does anyone have experience of this?
I'm using Ensembles 2.2 syncing through CloudKit.
Ensembles should handle this fine. I use it for exactly this purpose, syncing image data including PDF.
I would look closer at the handling of the data. Is the value transformer working (if you are using one)? Is the device capable of unpacking and displaying the PDF data?
An alternative to syncing the PDF directly is transforming to a format like PNG before putting it in your store.
Transformable data type is really just binary under the covers with some additional metadata. Have you tested a simple lightweight migration on an existing store? I suspect the migration would work and would leave the existing data in the store.
If you are looking to get the existing binary data actually moved out of the SQLite file then you are looking at something a bit more involved.
A heavy migration will accomplish what you are looking for but if the stores are large it may take took long and potentially not provide enough feedback for a good user experience. I personally do not use heavy migrations, ever, on IOS but it will accomplish your goal.
An export/import will also work. I generally recommend export/import when a lightweight migration won't work. It involves a medium amount of code but in the end you own the code, understand the entire process and can tweak it to your exact needs.
I have been tasked with creating an iPhone application for a client.
I have some coding experience but only in C# so it doesn't really help here but other than that I am a complete novice on iPhone coding.
What I am trying to accomplish is to get some form of store locator on a map.
I have successfully added the map, get the user location with it zooming into the user. I have added 2 annotations (Which I believe the the best way to go about showing locations on the map).
I have 2 queries that I need help with, What is the best way to go about listing the stores in some form of database. XML, PList, .sql etc... (this would also need to be read from the web as it would need to be easily edited as new stores would be added a lot). Is it possible to loop through the database and dynamically add the stores onto the map within a location of the user?
I am not asking anyone to write any code for me, I am just asking for some help as I have googled the hell out of this and cant seem to find anything that helps.
Any help would be much appreciated,
Thanks
In terms of your potential formats for saving these locations, you options include:
XML/JSON are good formats for exchanging data with a remote server, but less ideal for a local database (though they theoretically could be used for that purpose). JSON is marginally easier to deal with (using NSJSONSerialization), but XML can be relatively easily parsed, too (using, for example, NSXMLParser). If you're doing network operations, I also heartily recommend looking at AFNetworking, which offers some nice advantages over the standard NSURLConnection. This, of course, presumes that you have written a web service on your server to deliver the necessary JSON or XML feed.
Plist is a fine, simple format if you want to save a short, local list of locations on iOS devices. Saving data to a plist is as simple as calling writeToFile method for your NSDictionary or NSArray and reading data is done via [NSDictionary dictionaryWithContentsOfFile:filename] or [NSArray arrayWithContentsOfFile:filename].
Core Data is a good, iOS-specific format for larger databases. It's probably the preferred iOS mechanism for dealing with persistent objects, but is an order of magnitude more complicated than plists.
SQLite is also a good database format if you're thinking about a structure that lends itself towards larger database, but also which lends itself towards eventual rollout to multiple platforms (e.g. both Android and iOS). If you decide to go SQLite route, consider an Objective-C wrapper (such as FMDB), which will simplify your life greatly.
Implicit in all of the above discussion is that, yes, you certainly can write code that iterates through your database and/or model data structures, extracting the necessary location information, and dynamically add annotations to your map. The Location Awareness Programming Guide should help introduce you to some of the MapKit related features.
"Is it possible to loop through the database and dynamically add the stores onto the map within a location of the user?"
Yes. Just as you have created those first two annotations, you now need to create more annotations in a loop. The only additional info you might need is that once you have added an annotation to the map it will stay there until you remove it. So you don't need to maintain your own list of annotations unless you want to do something else with it. Just fire and forget. So now your question comes down to how to loop through data from your chosen data source in Objective-C and not MapKit specific.
I know this is old but if anyone else comes across this like I did, you can use tmysqlkit by tanmay bakshi to read and write directly to a mysql database on a server.
Best,
Sam
How do I parse OFX in iOS? OFX is formatted in SGML, and I can't find any good parsers to use in C or Objective-C on iOS.
Try using libofx. It depends on OpenJADE for SGML but I've gotten them both to compile and work on iOS.
There are a few challenges here:
(1) OFX 1.x documents are SGML-based, while 2.x documents are XML-based, so if you know you will only deal with 2.x documents you could probably use an XML parser.
(2) If you do have to deal with 1.x documents, you'll have some code-lifting ahead of you. SGML in general and OFX 1.x in particular do not enforce close tags for simple types. That means you'll see things like:
<INVACCTFROM>
<BROKERID>Fidelity Investments
<ACCTID>FidRoth
</INVACCTFROM>
Parsing this kind of thing will be tricky unless you provide your own schema logic, or pre-process the data to a more "valid" format. An example of the latter, while not in C/Obj-C/C++, is given on Scott Hanselman's blog.
Good resources on OFX can be found here.
I know of the US GIS TIGER file format from years ago, but have never used it.
I'm very shortly going to need to very quickly implement simple geocoding and vector graphics of roads and other features.
Where do I go for information - are there tutorials, example queries, etc?
Are there other ways to include geocoding and basic mapping in a mobile (no internet) device?
-Adam
As far as I'm aware of, there aren't many applications that make use of the TIGER/Line format directly. Most apps use TIGER files that have been translated into ESRI's shapefile format.
Edited to add:
Is there information on ESRI's format available?
There's an ESRI whitepaper describing the file format.
If you're planning to use shapefiles in an application, there are various libraries out there.
The OpenStreetMap project imported TIGER data, you might find useful code snippets there. See the TIGER page on the OpenStreetMap wiki for more information and links