ios,iphone,sqlite,core-data , Change database of Live App without Data Lose
Change database of Live App without Data Lose
Question:
Tag: ios,iphone,sqlite,core-data
I want to update the database of my existing app(for new version) which is live on the app store. So I need to delete my existing database before using app or I can change the name of the database. After it If data exists in my old database I have to get all data and insert it again to my new sqlite file.
It looks like a slow process. My users don't want to loose data. Is there any other way from which I can easily change database of my Existing App without any data lose.
Answer:
First you need to detect that the database is the old one. One way of doing that is to have a metadata table with name/value text columns (value is a reserved word, so use a different column name) and keep the current schemaVersion in there. If this doesn't exist then you know it's the older version, but from now on you need to keep that schenaVersion up-to-date during these updates. You can keep other information about the database itself in that table.
If the database is fundamentally different then you need to use the second approach you suggest:
- Detect if old version of database, if not abort update.
- Create new database with temporary file name. This includes setting-up the new schema.
- Open both databases at once.
- Iterate through tables in old database and take any necessary values in order to populate tables in new database.
- Close both databases.
- Remove old database file and move new, temporary, database file to old, existing, name.
- Open database and proceed.
Alternatively, if the changes are not drastically different then you can use the ALTER TABLE statement to modify the schema. This is the much better approach as it leaves values in place if the columns are not removed from the schema.
Related:
ios,sprite-kit,skphysicsbody
Suppose a circle is enclosed in a diamond, and the circle heads due right. I would expect a series of continual 90 degree angles as the circle draws a square within the diamond. What I'm seeing, however, is that the circle eventually gets pushed toward the center of the diamond...
ios,string,swift,unicode,character
Reading the documentation and this answer, I see that I can initialize a Unicode character in either of the following ways: let narrowNonBreakingSpace: Character = "\u{202f}" let narrowNonBreakingSpace = "\u{202f}" As I understand, the second one would actually be a String. And unlike Java, both of them use double quotes...
ios,objective-c,uitabbarcontroller
I'm using a standard UITabBarController with icons at the bottom, each bringing to it's ownViewController. My question is basically: Is there a way to override what happens when an icon is selected rather then directly bringing them to the view? Reason being is because I'm adding a login screen to...
ios,swift,autolayout
I have a UINavigationController that has my custom ViewController with a tableView in it that takes up the whole screen. I want to push down the tableView and reveal a settings menu with just a couple items. My SettingsView.xib I created in a separate nib that is 320 x 90...
ios,objective-c,asynchronous,uiviewcontroller,nsobject
In my app I init a new object, where there is method which calls NSURLConnection's sendAsynchronousRequest method. After the request, I would like to call a method in the caller UIViewController. I tried to use a static method but I then I can't control IBOutlets. How can I do this?...
ios,objective-c,nsdateformatter
now it works with this code: NSString *myDate = @"06/18/2015 8:26:17 AM"; NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; [dateFormatter setDateFormat:@"MM/dd/yyyy hh:mm:ss a"]; [dateFormatter setLocale:[NSLocale localeWithLocaleIdentifier:@"en_US"]]; NSDate *date = [dateFormatter dateFromString:myDate]; [dateFormatter setDateFormat:@"dd.MM. HH:mm"]; NSString *dateString = [dateFormatter stringFromDate:date]; cell.timeLabel.text = dateString; ...
ios,iphone,swift,audio,ios-simulator
In my iOS Swift application, and i am trying to play sound on click of a button. func playSound() { var audioPlayer = AVAudioPlayer() let soundURL = NSBundle.mainBundle().URLForResource("doorbell", withExtension: "mp3") audioPlayer = AVAudioPlayer(contentsOfURL: soundURL, error: nil) audioPlayer.play() } I am running the application in iOS iPhone Simulator. I have doorbell.mp3...
ios,xcode,xcode7,ios9,asset-catalog
I attributed to my .mp4 video the "tokyo" tag for example, and set it as installed during the app installation. Now before I was using a Path to get it from my resources, now it's different because it's located on the Asset Catalog. After found documentations, I tried something like...
ios,xcode,swift,uitableview,tableviewcell
I have a table view like this: when the user tap one row, I want uncheck the last row and check the selected row. So I wrote my code like this: (for example my lastselected = 0) func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) { var lastIndexPath:NSIndexPath = NSIndexPath(forRow: lastSelected, inSection:...
ios,swift,ios8,uiimagepickercontroller,ios8.3
- Actually am using UIImagePickerController for my usecase,and if i long press any picture ,it shows Copy/Hide option (as shown in the sample image) - I dont want the Copy/Hide feature. Guide me with some suggestions if u too have encountered :)... Thanks in advance...iOS Geeks...PLZ refer my code snippet...
javascript,python,ios,flask,twilio
I have created a simple twilio client application to make phone calls from Web Browser to phones. I used a sample Flask app to generate a secure Capability Token and used twilio.min.js library to handle calls from my HTML. The functionality works fine in Computer Browsers ans Android Phone Browsers,...
ios,uinavigationcontroller,swrevealviewcontroller
I have a login view controller which is outside my navigation controller. When a user logs out, I want them to be back to the login view controller. I am using SWRevealViewController and Storyboards. User Flow: -> Login View Controller -> SWRevealViewController-> UINavigationController...
ios,nsdateformatter
Has the parsing for timzones changed in iOS8? I try to parse the date "2014-09-03 12:20:38.000 +0200" with this code and get nil: -(NSDateFormatter*) dateAndTimeFormatter{ if(!_dateAndTimeFormatter){ _dateAndTimeFormatter = [[NSDateFormatter alloc]init]; [_dateAndTimeFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss.SSS ZZZZZ"]; _dateAndTimeFormatter.dateStyle = NSDateFormatterShortStyle; _dateAndTimeFormatter.timeStyle = NSDateFormatterShortStyle; } return _dateAndTimeFormatter; } alternatively [_dateAndTimeFormatter setDateFormat:@"yyyy-MM-dd...
ios,swift
I am trying to implement a class that will present a MFMessageComposeViewController from the AppDelegate. The class declaration looks like this: import UIKit import MessageUI class MyClass: NSObject, MFMessageComposeViewControllerDelegate { func sendAMessage() { // message view controller let messageVC = MFMessageComposeViewController() messageVC.body = "Oh hai!" messageVC.recipients = ["8675309"] // set...
ios,unity3d,shader,mesh,particle
How to draw each a vertex of a mesh as a circle?
ios,swift,cocoa-touch
I'm trying to get "Done" button on to load an action, preferably the action that I have for my button. Here's the UITextField declaration let someTextField = UITextField() Trying to add a target to the textField someTextField.addTarget(self, action: "loginActionButton", forControlEvents: .EditingDidEndOnExit) ...
ios,uiimage,title,uisegmentedcontrol
Is there a way so that you can set both image and title of UISegmentControl simultaneously, so that image appear next to the title , just like image appear next to title in UIButton. I am trying but if I set image of Selected segment of UISegmentControl then title disappears...
ios,swift
I am trying to get a time difference based on a GMT time. where at the end of everyday the timer resets to zero. I've tried the below code on the Xcode simulator and every time i change the time on the mac, the difference also changes. how can i...
ios,xcode,frameworks,transfer,projects
I am trying to copy over my Xcode project from one computer to another but it seems to lose frameworks and the locations for the images although i copied those too. PS I am using xcode and coding an app with a friend. Is there a useful source that can...
ios,objective-c,swift
I have SearchController for my TableViewController. I wanted to perform some actions when user taps on the empty space on the screen (between the keyboard and search bar) to dismisses the keyboard and displays the main Table View.
ios,objective-c,uitableview
I'm using insertion into my UITableView with this : Skill * newSkill = [[Skill alloc] init]; newSkill.name = @"Nouvelle compétence"; newSkill.pathPicto = @"generic"; [self.skills insertObject:newSkill atIndex:0]; NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0]; [self.tableView beginUpdates]; [self.tableView insertRowsAtIndexPaths:@[indexPath]withRowAnimation:UITableViewRowAnimationTop]; [self.tableView endUpdates]; It works great but now I want that the inserted cell be...
ios,iphone,swift
I think the question is pretty straightforward. I need only the date to appear, and not the time. Couldn't find anything for Swift, so my code is here: cell.date.text = NSDateFormatter.localizedStringFromDate(dates[indexPath.row], dateStyle: .ShortStyle, timeStyle: .ShortStyle) ...
ios,swift,swift2,ios9
The following URL opens on iOS 8.3 and lower, but it does not work and iOS 9 let instagramURL = NSURL(string: "instagram://app") Why won't the URL open?...
ios
I am making a project in which i am fetching addressbook in my tableview with the help of NSObject class. Now , I allocated a UISearchbar in it , but when i start typing , the app crashes with the following error :---- 'Can't use in/contains operator with collection (not...
ios,uistoryboard
Is it possible to have the storyboard scale everything up or down depending on the screen size or do I have to do it programmatically? For example the UI on iPhone 6 plus would look exactly like the one on iPhone 5 but just larger.
ios,swift
I just started learning Swift with Stanford tutorial. I have Xcode 6.3.2. I'm getting a bug at a switch operation and can't understand how to solve it. I attached a screenshot as well @IBAction func operate(sender: UIButton) { let operation = sender.currentTitle! if userIsInTheMiddleOfTypingANumber{ enter() } switch operation{ case "➕":...
ios,objective-c,xcode,swift,localization
I localized Info.plist : And I got this build error : error: could not read data from '/Users/cherif/Apps/Wesh/Info.plist': The file “Info.plist” couldn’t be opened because there is no such file. Actually there are now two Info.plist files : fr.lproj/Info.plist Base.lproj/Info.plist How to localize the Info.plist path ?...
ios,objective-c,ipod-touch
The iPod Touch (5th gen) has both a front and rear camera so why does my app crash when i try to present a UIImagePickerController with sourceType: UIImagePickerControllerSourceTypeCamera - (void)openImagePickerType:(NSString *)type { UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init]; imagePicker.delegate = self; if([type isEqualToString:kImagePickerCameraString]) imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera; if([type isEqualToString:kImagePickerLibraryString]) imagePicker.sourceType =...
ios,uitableview
I made a custom cell from my storyboard, with an UIImageView and a UILabel. Each of them have a tag 100 for the imageView and 102 for UILabel. I try to get them in my datasource method but as below, they are still nil and I don't know why. ...
ios,swift,plist
i am trying to read from propriety list using swift but im getting this error, and thats the code im using to read from my plist : Arrays i'm using : var recipeNames :[String] = [] var recipeImages :[String] = [] var recipeTime :[String] = [] In viewDidload : var...
ios,user-interface,uiviewcontroller
I want to make my whole ViewController grey except I want the top area where it shows CARRIER and the current time to remain white. Is the only way just to stick a View that covers everything except that area, and set it to grey, or is there some way...
ios,objective-c,swift,uitextfield,uilabel
In my application i have one UILabel and UITextField. Initially UILabel text in nil. As soon as user enter some text in UITextField my UILabel text also Update. Let say When user enter A in UITextField my UILabel immediately show A, B in UITextField my UILabel show B and so...
ios,swift,uitableview
When I expand a UITableViewCell on touch, I know I have to update the UITableView. Right now I'm doing: tableView.beginUpdates() tableView.reloadRowsAtIndexPaths(indexPaths, withRowAnimation: UITableViewRowAnimation.Automatic) tableView.endUpdates() Do I need to use both updates methods as well as the reload method? Or is it just one or the other? I'm not completely understanding,...
ios,xcode,swift,uigesturerecognizer
I've got a button called and I gave it a UIGestureRecognizer so that an IBAction is only run when the button is long pressed. You do this by adding a UILongPressGestureRecognizer to the button iteself. Then you control drag that gesture recognizer to a function like this: @IBAction func handleGesture(sender:...
ios,objective-c,swift
I have this instance method in an existing Obj-C UIImage category: - (UIImage *)applyDarkEffect; I'm trying to call it from a Swift file like so: self.backgroundImageView.image = UIImage.applyDarkEffect(image) But get this compiler error: Function produces expected type 'UIImage!'; did you mean to call it with '()'? ...
ios,uitableview
Scenario: Embedded UITableView in a standard UIViewController's view. Three (3) 80-pt rows fill the UITableView. Problem: UITableView doesn't scroll until the number of rows > 5. I've tested this by varying the number of displayed rows and attempted to scroll. Three (3) rows fills the UITableView. Four (4) fills but...
ios,objective-c,uipopovercontroller
I'm trying to dismiss a popover when selecting a cell inside of it. I have created a custom delegate to support this however it is not working: In my class that houses the PopOver and table View I have the following: In .h: @protocol DismissDelegate <NSObject> -(void)didTap; @end @interface AssistanceNeededAtPopOverViewController...
ios,swift,applovin
I would like some help with integrating interstitial ads from Applovin using Swift. Currently, I have managed to successfully integrate the SDK and initialize it using ALSdk.initializeSdk(). I have a folder in my project directory called Applovin which contains: headers folder (with all the .h files inside) and libApplovinSdk.a. I...
ios,swift,uitableview,cocoa-touch,ios-charts
I am working on a project where I have a table view which contains a number of cells with pretty complex content. It will be between usually not more than two, but in exceptions up to - lets say - 30 of them. Each of these complex cells contain a...
ios,uitabbarcontroller,auto-rotation,shouldstartload
I have a UITabBarViewController that contains 5 tabs and a login view which is not part of my tab bar, in my settings I have set that I support all device orientations. but when I run my app, only my login view is the only which rotates. I have created...
ios,iphone,cocoa,ipad,icloud
My iOS app is currently on beta in TestFlight, and as a way to retribute to the nice people who helped me test it I would like to offer them some goodies such as, for instance, the full final version of the app for free. For this, I was thinking...
ios,objective-c
I have this methods for draw a table ant populated . What i want is to change the color for one word from each column , but i dont know how can i do it . Can somebeday help me ,please ? Any help will be appreciate . in my...
ios,uitableview,autolayout
im trying to build apps that have tableview cell similiar with twitter, there are text and images. My problem is i want to insert the image above the text. While it can be text only. So if there are no image, the text will be in position (0,0). And if...
ios,swift,uitableview,uiviewcontroller
In order to customize a table view and add some additional controls to it, I've embedded a UTTableViewController into a Container View and placed that container View into a UIViewController. I've followed the instructions I found here: Embedding TableView in TableViewController into another view TableView is configured with four static...
ios,objective-c,automatic-ref-counting
I came across to strange behaviour. I used to have: @property (nonatomic) ApplicationState applicationState; directly in my Application class. Now it's extracted to protocol @protocol ApplicationProtocol <NSObject> @property (nonatomic) ApplicationState applicationState; ApplicationState is Enum typedef NS_ENUM(NSUInteger, ApplicationState) { ApplicationStateNormal = 0, ApplicationStateExpanded = 1, ApplicationStateMaximized = 2 }; Now. It...
ios,objective-c,swift,video
I want to add background view with video (or gif) like in app "Uber" I'd like to use video background view for a long time in my app. And I want to know the answers to these questions: What of them will consume less battery energy Can I use it...
ios,objective-c,swift,nsstring,nsmutablestring
What is the difference between stringByAppendingString and appendString? If NSString is not mutable then how could it append string?