Data Persistence basics-List of attributes

Property list:

1 //Insert 4 text boxes2@property (Strong, Nonatomic) iboutletcollection (Uitextfield) Nsarray *Linefields;3 4 5 //gets the path, checks whether the data file exists, and appears in the text box. 6- (void) Viewdidload {7 [Super Viewdidload];8NSString * FilePath =[self datafilepath];9     if([[[Nsfilemanager Defaultmanager] Fileexistsatpath:filepath]) {TenNsarray * Array =[[Nsarray alloc] initwithcontentsoffile:filepath]; One          for(inti =0; I <4; i++) { AUitextfield * Thefield =Self.linefields[i]; -Thefield.text =Array[i]; -         } the     } -  - //Save the data before terminating the operation or entering the background.  -UIApplication * App =[UIApplication sharedapplication]; +[[Nsnotificationcenter Defaultcenter] addobserver:self selector: @selector (applicationwillresignactive:) Name: UiapplicationwillresignactivenotificationObject: app]; - } +  A //gets the file path and returns.  at-(NSString *) DataFilePath - { -Nsarray * paths =nssearchpathfordirectoriesindomains (NSDocumentDirectory, Nsuserdomainmask, YES); -NSString * documentsdirectory = [Paths Objectatindex:0]; -     return[Documentsdirectory stringbyappendingpathcomponent:@"data.plist"]; - } in  - //the method to execute before terminating or entering the background.  to- (void) Applicationwillresignactive: (Nsnotification *) Notification + { -NSString * FilePath =[self datafilepath]; the      *      //construct an array of strings by calling the text method of each textbox in the Linefields array, calling the Valueforkey: method, and passing the @ "text" as the parameter, which implements iterating to get the text value of the instance variable.  $Nsarray * array = [Self.linefields Valueforkey:@"text"];Panax Notoginseng [Array Writetofile:filepath atomically:yes]; -}

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Data Persistence basics-List of attributes