如何将tableview行保存到文件并重新加载到tableview

Question

I have a simple tableview and I populated it with a text.field :

@interface ListaDeProdutosTableViewController ()

@property NSMutableArray *produtos;

@end

@implementation ListaDeProdutosTableViewController

Now I want to save this rows to a file (to persist data) and read it back to tableview. How can I do this?

Can you help me? Thank you!

Answer 1

Not sure what you want to save, but here's an example how to save object to file and read it later:

- (NSString *)cachePath {
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
    return [paths objectAtIndex:0];
}

- (void)cacheObject:(NSString *)objectId withData:(SomeClass *)objectData{
    NSData *data = [NSKeyedArchiver archivedDataWithRootObject:objectData];
    NSString *path = [NSString stringWithFormat:@"%@/someobject-%@.cache", [self cachePath], objectId];
    [data writeToFile:path atomically:YES];
}

- (SomeClass *)getObjectCache:(NSString *)objectId {
    NSString *path = [NSString stringWithFormat:@"%@/someobject-%@.cache", [self cachePath], objectId];
    NSData *data = [NSData dataWithContentsOfFile:path];
    if (!data) {
        return nil;
    }
    SomeClass *object = [NSKeyedUnarchiver unarchiveObjectWithData:data];
    return object;
}