How to save apps data Xcode
I have been searching for many days on how to save my apps data. I found some stuff but it was ver开发者_开发百科y complicated and badly explained. I need that when I completely close my apps all the data I entered in the text field are still there when I open my apps again. I tried a tutorial but this only let me save about 8 textfields and I need to save thousands I am starting Objective-C and Xcode so if somebody want to give me an answer please make it very precise.
Alright, what I'd suggest would be putting all the data from your text fields into an array and saving that to a file, then loading it when you re-open the app.
The first thing you need is a save file. This function will create one for you.
-(NSString*) saveFilePath{
NSString* path = [NSString stringWithFormat:@"%@%@",
[[NSBundle mainBundle] resourcePath],
@"myfilename.plist"];
return path;}
Now that that's done you need to create your saving array. Hopefully you have your thousands of textfields already fitted into an array of some sort. If not, this will be a painful process regardless of how you tackle it. But anyway... (Here, labelArray will be the array of all your text fields/labels/etc.)
NSMutableArray* myArray = [[NSMutableArray alloc]init];
int i = 0;
while(i < labelArray.count){
[myArray addObject: [labelArray objectAtIndex: i].text];
i ++;
}
[myArray writeToFile:[self saveFilePath] atomically:YES];
[myArray release];
And the loading code would be something along the lines of
NSMutableArray* myArray = [[NSMutableArray arrayWithContentsOfFile:[self saveFilePath]]retain];
Then you'd simply load the data back into your array of text fields.
Hope this helps.
It sounds like your application architecture may be unsound if you are planning on saving thousands of text fields' data in the fraction of a second you get while your app is closing. It would probably be better to save these as the user enters the data instead of waiting to save all the data at once.
To get the path you are going to write ( or read from! ) to, you do the following:
NSString *writableDBPath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:@"MyFile.extension"];
And then use a method like "writeToFile:automically:" of NSString or NSDictionary etc. to write to the path.
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