How do I parse through an array of objects in Objective-C? - objective-c

Question

Coming from C++, here's my question :
I have created objects of this type :
Size *one = [[Size alloc] initWithX: 3 andY: 1];
Size *two = [[Size alloc] initWithX: 4 andY: 7];
// etc...
Size *thirtythree = [[Size alloc] initWithX: 5 andY: 9];
( with a #property int x; & #property int y; for each object.. )
that I have stored in an array as follows :
NSArray *arrayOfSizes;
arrayOfSizes = [NSArray arrayWithObjects:one,two,three,four,five,six,
seven,eight,nine,ten,eleven,twelve,thirteen,
fourteen,fifteen,sixteen,seventeen,eighteen,
nineteen,twenty,twentyone,twentytwo,
twentythree,twentyfour,twentyfive,twentysix,
twentyseven,twentyeight,twentynine,thirty,
thirtyone,thirtytwo,thirtythree nil];
now I have a single object of type :
Myobject *myObject = [[Myobject alloc] initWithX: 5 andY: 3];
that also has a #property int x; & #property int y; ...
and I want to compare its values to the values of the objects found in the array, until I find an array object of similar values.. But I don't know how to do that in Obj-C. (in c++ I would simply use a vector v; with v.size(); and v[x]; ..etc... I suppose..)
here's what I'm looking for.. :)
while( !wholeOfArrayOfSizesChecked && !found)
{
if ( // x & y of object in array is equal to x & y of myObject )
{
found = YES;
}
else if( // whole of array checked)
{
wholeOfArrayOfSizesChecked = YES;
}
else
{
//move on to the next object of the array..
}
}
Thanks in advance for any help!

Answer 1

Well, you could just use fast enumeration on the array. Something like this:
Myobject *myObject = [[Myobject alloc] initWithX: 5 andY: 3];
for (Size *s in arrayOfSizes)
{
if (s.x == myObject.x && s.y == myObject.y)
{
// Found one
// Do something useful...
break;
}
}

Answer 2

Another one:
NSUInteger index = [arrayOfSizes indexOfObjectPassingTest:
^BOOL(Size *s, NSUInteger idx, BOOL *stop)
{
return (s.x == myObject.x) && (s.y == myObject.y);
}
];
if (index != NSNotFound) {
id object = [arrayOfSizes objectAtIndex:index];
}

Answer 3

Just to use your given structure. There are smarter ways of doing it though :)
wholeOfArrayOfSizesChecked = NO;
int currObj = 0
while( !wholeOfArrayOfSizesChecked && !found)
{
Size *current = (Size *)[arrayOfSizes objectAtIndex:i];
if (myObject.x == current.x && myObject.y == current.y)
{
found = YES;
}
else if(currObj == [arrayOfSizes count] -1 )
{
wholeOfArrayOfSizesChecked = YES;
}
else
{
currObj++;
}
}

Answer 4

Try something like this:
for (int i = 0; i < [arrayOfSizes size]; i++)
{
Size *current = (Size *)[arrayOfSizes objectAtIndex:i];
if (myObject.x == current.x && myObject.y == current.y)
{
// found
break;
}
}

Answer 5

How'bout a for-in loop?
for (Size *item in array) {
// compare 'item' to myObject
if (/* equal condition here */) break;
}

Answer 6

-(BOOL) isSize:(Size*)size equalToMyObject:(MyObject*)object{
return (size.x == object.x) && (size.y == object.y);
}
//In some method where you are checking it:
for (Size* size in arrayOfSizes){
if ([self isSize:size equalToMyObject:myObject]){
//You found it! They're equal!
break;
}
}