Array just keeps adding object and memory Crash - ios

Question

I am recently having a memory crash and I am suspecting that I am failing to empty the array, This is my code for the array
- (void)viewDidLoad
{
allImagesArray = [[NSMutableArray alloc] init];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *location=#"Bottoms";
NSString *fPath = [documentsDirectory stringByAppendingPathComponent:location];
NSArray *directoryContent = [[NSFileManager defaultManager] directoryContentsAtPath: fPath];
collectionBottoms.delegate =self;
collectionBottoms.dataSource=self;
for(NSString *str in directoryContent){
NSLog(#"i");
NSString *finalFilePath = [fPath stringByAppendingPathComponent:str];
NSData *data = [NSData dataWithContentsOfFile:finalFilePath];
if(data)
{
UIImage *image = [UIImage imageWithData:data];
[allImagesArray addObject:image];
NSLog(#"array:%#",[allImagesArray description]);
}}
}
Ho can I free the memory by releasing the object in the array?

Answer 1

You save the image array in Plist. After save you just re initialize your array it will clear the memory in array. Then are you using ARC or not? Because ARC is more comfortable for this. Then re-initialze or removeAllObject from array in -viewWillDisappear

Answer 2

Hi Just release the memory once object works is over. Here is the code for you.
- (void)viewDidLoad
{
allImagesArray = [[NSMutableArray alloc] init];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *location=#"Bottoms";
NSString *fPath = [documentsDirectory stringByAppendingPathComponent:location];
NSArray *directoryContent = [[NSFileManager defaultManager] directoryContentsAtPath: fPath];
collectionBottoms.delegate =self;
collectionBottoms.dataSource=self;
for(NSString *str in directoryContent)
{
NSString *finalFilePath = [fPath stringByAppendingPathComponent:str];
NSData *data = [NSData dataWithContentsOfFile:finalFilePath];
if(data)
{
UIImage *image = [UIImage imageWithData:data];
[allImagesArray addObject:image];
NSLog(#"array:%#",[allImagesArray description]);
image = nil;
}
finalFilePath=nil;
data=nil;
}
paths= nil;
documentsDirectory= nil;
location= nil;
fPath= nil;
directoryContent = nil;
}

Answer 3

If you are using this image array, allImagesArray, when the view is visible then put this code in viewWillAppear or viewDidAppear methods of UIViewController.
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
allImagesArray = [[NSMutableArray alloc] init];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *location=#"Bottoms";
NSString *fPath = [documentsDirectory stringByAppendingPathComponent:location];
NSArray *directoryContent = [[NSFileManager defaultManager] directoryContentsAtPath: fPath];
collectionBottoms.delegate =self;
collectionBottoms.dataSource=self;
for(NSString *str in directoryContent){
NSLog(#"i");
NSString *finalFilePath = [fPath stringByAppendingPathComponent:str];
NSData *data = [NSData dataWithContentsOfFile:finalFilePath];
if(data)
{
UIImage *image = [UIImage imageWithData:data];
[allImagesArray addObject:image];
NSLog(#"array:%#",[allImagesArray description]);
}
}
}
And, then release it in viewWillDisappear/viewDidDisappear methods of UIViewController.
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
[allImagesArray removeAllObjects];
//[allImagesArray release]; // (Uncomment) Call this only if you are not using ARC.
}
Alternatively, a quick, dirty but safe fix is (without knowing your usage of allImagesArray) -
- (void)viewDidLoad
{
[super viewDidLoad];
// Remove previously added objects.
if (allImagesArray != nil && allImagesArray.count > 0) {
[allImagesArray removeAllObjects];
}
// Allocate memory if not done earlier (i.e. first time).
if (allImagesArray == nil) {
allImagesArray = [[NSMutableArray alloc] init];
}
// Rest of your code as stated in your question
}