how to create an array of string or float in Objective-C
i need some help here, i need to know how to create an array of string retrieved from an array. i'm using powerplot for graph and it only accept float or string array.
i need to create something something like this dynamically.
NSString * sourceData[7] = {@"2", @"1", @"4", @"8", @"14", @"15", @"10"};
Below are my code to find out the numbers in strings.
NSInteger drunked = [appDelegate.drinksOnDayArray count];
NSMutableArray * dayArray = [[NSMutableArray alloc] init];
NSMutableArray * sdArray = [[NSMutableArray alloc] init];
//float *sdArray[7];
for (int i=0; i<drunked; i++) {
DayOfDrinks *drinksOnDay = [appDelegate.drinksOnDayArray objectAtIndex:i];
NSString * dayString= [NSDate stringForDispla开发者_JAVA百科yFromDateForChart:drinksOnDay.dateConsumed];
[dayArray addObject:dayString];
NSLog(@"%@",[dayArray objectAtIndex:i]);
drinksOnDay.isDetailViewHydrated = NO;
[drinksOnDay hydrateDetailViewData];
NSString * sdString= [NSString stringWithFormat:@"%@", drinksOnDay.standardDrinks];
[sdArray addObject:sdString];
NSString *tempstring;
NSLog(@"%@",[sdArray objectAtIndex:i]);
}
thanks for the help :)
Array's in Objectice-C aren't that hard to work with:
NSMutableArray *myArray = [NSMutableArray array];
[myArray addObject:@"first string"]; // same with float values
[myArray addObject:@"second string"];
[myArray addObject:@"third string"];
int i;
int count;
for (i = 0, count = [myArray count]; i < count; i = i + 1)
{
NSString *element = [myArray objectAtIndex:i];
NSLog(@"The element at index %d in the array is: %@", i, element); // just replace the %@ by %d
}
You can either use NSArray
or NSMutableArray
- depending on your needs, they offer different functionality.
Following tutorial covers exactly what you are looking after:
http://www.cocoalab.com/?q=node/19
You can also add the elements to the array when you init (and optionally add them later only if you are using the Mutable
version of a collection class:
NSMutableArray *myArray = [[NSMutableArray alloc] initWithObjects:@"2", @"1", @"4", @"8", @"14", @"15", @"10", nil];
[myArray addObject:@"22"];
[myArray addObject:@"50"];
//do something
[myArray release];
You can use malloc to create a C-style array. something like this should work:
NSString **array = malloc(numElements * sizeof(NSString *))
some code here
free(array)
Be aware that unlike NSMutable array, c arrays won't do a retain, so you have to manage it if needed. And don't forget the free
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