Is there a way by which I can directly use mbtiles database with MKTileOverlay without using a third party framework like MapBox or any other?
Right now, I have the tiles stored in a folder structure and the code I am using is below:
NSString *tileDirectory = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:#"Tiles"];
NSString *tileDirectoryURL = [NSURL fileURLWithPath:tileDirectory isDirectory:YES];
NSString *tileURL = [NSString stringWithFormat:#"%#Z{z}/{y}_{x}.png", tileDirectoryURL];
tileOverlay = [[MKTileOverlay alloc] initWithURLTemplate:tileURL];
[tileOverlay setGeometryFlipped:YES];
[mainMapView addOverlay:tileOverlay];
But now I want to have a tiles.mbtiles sqlite database instead of the files in folders.
Please suggest me how can I do this. How do I initialize the MKTileOverlay object if I choose to use sqlite database. How will I put {x},{y},{z}.
I went through the documentation of MKTileOverlay and found that :
- (void)loadTileAtPath:(MKTileOverlayPath)path result:(void (^)(NSData *tileData, NSError *error))result
can be used but I am not able to understand how can I use it? If any one can please give ma a short example then it would be very helpful.
You could take a look at how this project does it…
https://github.com/t2wu/OSMMapKit
It doesn't seem to be finished yet but it should get you on the right path.
Related
I am working on widget app. I am totally new to Today Extension. I want to share data between app and today extension. I have created one database. I have 4 tables in that database. I found this code to create database for App Groups :
NSString *appGroupId = #"group.appname";
NSURL *appGroupDirectoryPath = [[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:appGroupId];
dataBaseURL = [appGroupDirectoryPath URLByAppendingPathComponent:#"database.sqlite"];
NSLog(#"dataBaseURL %#", dataBaseURL);
It worked. My SQLite file has been created. But It does't show my tables. It shows empty database. I don't have any idea about it. Please help.
If you are creating new database then it will obviously empty.
first thing you can create data base with tables in objective c. there is no need to create database from outside the xcode and drag and drop yto xcode. you can refer this techotopia tutorial for that.
Now if you put database in your main bundle by drag and drop then you can access that like,
NSString *databasePath = [[NSBundle mainBundle] pathForResource:#"myDbName" ofType:#"sqlite"];
by this way you can get your database path. here pathforresource is your database name, i think database in your case and oftype is extention, i think sqlite in your case.
now you get path as string if you want it in url then you can convert it in url like,
NSURL *fileURL = [[NSURL alloc] initFileURLWithPath:filePath];
or
NSURL *fileURL = [NSURL fileURLWithPath:filePath];
Hope this will help :)
Here is the NSURL object that I am using for creating and accessing important configuration file on iOS with features:
hidden from user
not user generated file (storing configuration related to user)
not temp or cache (not possible to create later with existing data)
must be backed up by iCloud/iTunes
[NSURL fileURLWithPath:[[NSSearchPathForDirectoriesInDomains(
NSLibraryDirectory,
NSUserDomainMask,
YES) objectAtIndex:0]
stringByAppendingString:#"/important.txt"]];
As suggested in FileSystemOverview (developer.apple.com), I am storing this file under Library.
Maybe better way is storing it under Library/Application Support.
Using NSSearchPathForDirectoriesInDomains, which takes:
enum NSSearchPathDirectory
NSApplicationDirectory
NSDeveloperApplicationDirectory
NSLibraryDirectory
NSDeveloperDirectory
NSApplicationSupportDirectory
...
enum NSSearchPathDomainMask
NSUserDomainMask
NSLocalDomainMask
NSSystemDomainMask
...
BOOL expandTilde
Is this the correct way of storing such a file?
There are couple of alternatives for NSSearchPathDirectory and NSSearchPathDomainMask.
Also what about the expandTilde, on iOS is it necessary?
Is there a better way of doing it, instead of creating path as a NSString using objectAtIndex and appending file name then converting it to NSURL?
Thanks.
Using NSApplicationSupportDirectory would be my first choice for this.
But keep a few things in mind:
Unlike the "Documents" folder, the "Library/Application Support" folder doesn't exist in an iOS app sandbox by default so you must create the folder before trying to use it.
"Hidden from the user" only means that the user won't see it under normal circumstances. But the file is easily accessible by anyone with any technical knowledge.
You do want to pass YES for the expandTilde parameter so your app returns a proper path when you run the app in the simulator. On a real iOS device, it makes little difference.
Do not use stringByAppendingString: to create paths. Use stringByAppendingPathComponent:.
NSString *appSupportPath = [NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES) firstObject];
NSString *filePath = [appSupportPath stringByAppendingPathComponent:#"important.txt"];
NSURL *fileURL = [NSURL fileURLWithPath:filePath];
You can get a direct NSURL using NSFileManager:
NSURL *appSupportURL = [[[NSFileManager defaultManager] URLsForDirectory:NSApplicationSupportDirectory inDomains:NSUserDomainMask] firstObject];
NSURL *fileURL = [appSupportURL URLByAppendingPathComponent:#"important.txt"];
I have to share my OS X app, all the paths I have used for files used by project are linked to my username and the structure of my computer.
Is there a way to have paths related to my project so that once my project is shared the user may not get in troubles caused by 'file not found'.
I would move the used files of the project, into the project but then I don't know how to let this happen:
actual paths, what I use now:
/Users/???username???/XCode/projectName/fileName.txt
what I would like to use in my code:
function(path: fileName.txt)
how don't know how to make the paths this short, not caring about the users directories since the files I'm going to use are all inside my project.
I am very confused. Thank you.
There is actually an easy way to read files from your project directory:
NSError *error = nil;
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"filename" ofType:#"txt"];
NSString *dataContent = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:&error];
So in dataContent you have the content of the file as an NSString instance.
I am trying to construct a library in IOS.
In my library ,I use a method -(void)loadNewData to load some data EX:test.csv.
But when I export my library and let the other app use my library to excute the loadNewData method.
I found it can not be load correctly. It seems that because there is not such a file test.csv in the app.
How should I revise my code? Or where should I notice when I export the library?
Thank you for watch my question.
And sorry for my poor English.
Here is the a part of code of the loadNewData:
NSString *resourcePath = [[NSBundle mainBundle] resourcePath];
NSString *Rawsurveys=[resourcePath stringByAppendingPathComponent:#"test.csv"];
NSString *RawsurveyResults;
if([[NSFileManager defaultManager]fileExistsAtPath:Rawsurveys])
{
NSLog(#"find file");
NSFileHandle *RawfileHandle=[NSFileHandle fileHandleForReadingAtPath:Rawsurveys];
RawsurveyResults=[[NSString alloc]initWithData:[RawfileHandle availableData] encoding:NSUTF8StringEncoding];
[RawfileHandle closeFile];
}
You could probably create a bundle within your library and add you test.csv there.
Then you can access your test.csv from your own bundle.
Example of how I use images from my bundle. [UIImage imageNamed:#"myBundle.bundle/myImage"]. You could use the somewhat same for your file
I'm having a problem with the code I'm writing.
I'm writing an iOS program (I'm an iOS rookie) which basically requires me to use quick look framework to view some documents on the iPhone (*.doc, *.ppt, *.pdf etc..) which are stored in the database (Core Data - SQLite, nothing external). I need to add the files somehow, but since iOS isn't really allowing me to browse through its file system I can't find and save the documents i need in database. Which kinda blocks everything else i need to do until I can get those documents from the database. (to set up table views that list the files and the details about the files etc.)
This is for a class project so it doesn't need to be perfect condition, I just need to be able to browse through a few documents while I'm presenting the project. I can add all the documents I'm going to use at one time while I'm coding and I won't need to be able to add any new files when I'm using the program during the presentation. And I don't want it to make it more complicated if i don't have to. Like connecting to an external database with the files already saved in and use a php buffer-page to connect to that database or anything like that. I don't have the necessary server system to execute that php file. I want this operation to be done inside the phone.
The solutions I was able to think of so far:
Grab some random office files from the internet and save them into the database. Then use them later.
Create image scans of some office files and "cheat" by using the scanned image instead of actual documents.
I would really appreciate it if someone can tell me another and much easier way to handle this. Please just keep in mind that while I have a programming background with Java and C#, I'm still an iOS rookie and just barely moving on from scratching the surface. So it is likely that I don't know about something iOS provides by default and I'm just pulling my hair out for nothing.
I think thats it, I hope I didn't forget anything. If you need more details I'm going to be here and I can provide them almost instantly. Thanks everyone in advance for your help.
It sounds like NSFileManager will help you.
If you place your documents into your project tree, they will be available to your app. Use NSFileManager to copy them into the app's Documents folder using something like:
- (void)placeBundleFileInDocuments:(NSString *)filename
{
NSFileManager *fileManager = [NSFileManager defaultManager];
NSString *bundlePath = [[NSBundle mainBundle] pathForResource:[[filename lastPathComponent] stringByDeletingPathExtension] ofType:[filename pathExtension]];
NSString *documentsFolderPath = [NSString stringWithFormat:#"%#/", [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]];
NSString *path = [documentsFolderPath stringByAppendingPathComponent:[NSString stringWithFormat:#"%#", filename]];
if ([fileManager fileExistsAtPath:path])
return;
NSError *error = nil;
[fileManager copyItemAtPath:bundlePath toPath:path error:&error];
if (error) {
NSLog(#"Unable to copy file (%#).", error.localizedDescription);
}
}
Then, you can use NSFileManager to retrieve details about the files. You might find this method useful:
- (NSDictionary *)attributesOfItemAtPath:(NSString *)path error:(NSError **)error
I hope this helps!