I have a problem with a piece of code that should add images to a NSMutableArray. For some reason the images are not added (the count of the array stays at 0). Can someone please tell me what I'm doing wrong here?
- (void)incomingNotification:(NSNotification *)notification {
[self.popoverController dismissPopoverAnimated:YES];
_URLString = [notification object];
for (int i = 0; i < [[self returnLargeUrls] count]; i++) {
[self getImageFromURL:_URLString];
}
}
And in getImageFromUrl::
-(NSData *) getImageFromURL:(NSString *)fileURL {
UIImage *result;
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:fileURL]];
result = [UIImage imageWithData:data];
[self.pageImages addObject:result];
NSLog(#"%d", self.pageImages.count);
return data;
}
The first thing to check would be that you property pageImages is not nil to begin with.
You can check that like:
if(!pageImages)
NSLog(#"The NSMutableArray pageImages is NIL. Damn... :(");
This is most likely your problem.
Make sure you alloc init your NSMutableArray first.
Make sure your NSData is not nil after fetching contents from URL. NSLog(#"%#", data);
Related
I'm trying to add my UIImage from web service to my NSMutableArray using this code:
for (int i=0; i<[totalRowCountString intValue]; i++)
{
NSString *criticsRatingString = [[JSON valueForKeyPath:#"movies.ratings.critics_rating"] componentsJoinedByString:#" "];
NSLog(#"criticsRatingString: %#", criticsRatingString);
if ([criticsRatingString isEqualToString:#"Certified Fresh"])
{
self.ratingImage = [UIImage imageNamed:#"rt_certified_fresh.png"];
}
else if ([criticsRatingString isEqualToString:#"Fresh"])
{
self.ratingImage = [UIImage imageNamed:#"rt_fresh.png"];
}
else if ([criticsRatingString isEqualToString:#"Rotten"])
{
self.ratingImage = [UIImage imageNamed:#"rt_rotten.png"];
}
else if ([criticsRatingString isEqualToString:#"Spilled"])
{
self.ratingImage = [UIImage imageNamed:#"rt_spilled.png"];
}
else if ([criticsRatingString isEqualToString:#"Upright"])
{
self.ratingImage = [UIImage imageNamed:#"rt_upright.png"];
}
[tomatorRatingImages addObject:self.ratingImage];
NSLog(#"tomatoRatingImages: %#", tomatorRatingImages);
}
But my NSLog for tomatoRatingImages returns NULL. Any ideas why it returns NULL?
UPDATE: my NSMutableArray is already initialized in my viewWillAppear method.
You must initialize the array before adding objects to it.
NSMutableArray *tomatorRatingImages = [[NSMutableArray alloc] init];
NSMutableArray * tomatorRatingImages =[[NSMutableArray alloc]init];
[tomatorRatingImages addObject:[UIImage imageNamed:#"rt_spilled.png"]];
[tomatorRatingImages addObject:[UIImage imageNamed:#"rt_spilled1.png"]];
[tomatorRatingImages addObject:[UIImage imageNamed:#"rt_spilled2.png"]];
you can enter multiple image in NSMutableArray.
If you have a property for the NSMutableArray instance, it's better to write getter to initialize it. It takes care of initializing the variable only ones also it gets loaded only when it's required.
-(NSMutableArray *) tomatorRatingImages {
if(_tomatorRatingImages == nil) {
_tomatorRatingImages = [NSMutableArray alloc] init];
}
return _tomatorRatingImages;
}
Initialize like this
NSMutableArray * tomatorRatingImages =[[NSMutableArray alloc]initWithCapacity:3];
I'm very new to programming, and I jumped right into a project (I know thats not the smartest thing to do, but I'm learning as I go). The app that I'm writing has 10 UIImageViews that display a picture from the users camera roll. The code I'm using needs each of the UIImageViews to have tags. I'm currently using NSData to save the array images, and it works great, but I can't use this method anymore because NSData doesn't support the use of tags. I also can't use NSUserDefaults, because I can't save images to a plist. Here is how I'm attempting to do this (using the NSData method, which works but I have to edit this so that my tags work.)
This is my current code:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
if (imageView.image == nil) {
imageView.image = img;
[self.array addObject:imageView.image];
[picker dismissModalViewControllerAnimated:YES];
[self.popover dismissPopoverAnimated:YES];
return;
}
if (imageView2.image == nil) {
imageView2.image = img;
NSLog(#"The image is a %#", imageView);
[self.array addObject:imageView2.image];
[picker dismissModalViewControllerAnimated:YES];
[self.popover dismissPopoverAnimated:YES];
return;
}
...
- (void)applicationDidEnterBackground:(UIApplication*)application {
NSLog(#"Image on didenterbackground: %#", imageView);
[self.array addObject:imageView.image];
[self.array addObject:imageView2.image];
[self.user setObject:self.array forKey:#"images"];
[user synchronize];
}
- (void)viewDidLoad
{
self.user = [NSUserDefaults standardUserDefaults];
NSLog(#"It is %#", self.user);
self.array = [[self.user objectForKey:#"images"]mutableCopy];
imageView.image = [[self.array objectAtIndex:0] copy];
imageView2.image = [[self.array objectAtIndex:1] copy];
UIApplication *app = [UIApplication sharedApplication];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(applicationDidEnterBackground:)
name:UIApplicationDidEnterBackgroundNotification
object:app];
[super viewDidLoad];
}
Any help or suggestions on how to edit this code so that I can save the images, while using tags is much appreciated, thanks!
EDIT: Here is my updated code:
-(IBAction)saveButtonPressed:(id)sender {
NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES) objectAtIndex:0];
for (UIImageView *imageView in self.array) {
NSInteger tag = self.imageView.tag;
UIImage *image = self.imageView.image;
NSString *imageName = [NSString stringWithFormat:#"Image%i.png",tag];
NSString *imagePath = [docsDir stringByAppendingPathComponent:imageName];
[UIImagePNGRepresentation(image) writeToFile:imagePath atomically:YES];
}
NSLog(#"Saved Button Pressed");
}
- (void)applicationDidEnterBackground:(UIApplication*)application {
}
-(void)viewDidLoad {
NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES) objectAtIndex:0];
NSArray *docFiles = [[NSFileManager defaultManager]contentsOfDirectoryAtPath:docsDir error:NULL];
for (NSString *fileName in docFiles) {
if ([fileName hasSuffix:#".png"]) {
NSString *fullPath = [docsDir stringByAppendingPathComponent:fileName];
UIImage *loadedImage = [UIImage imageWithContentsOfFile:fullPath];
if (!imageView.image) {
imageView.image = loadedImage;
} else {
imageView2.image = loadedImage;
}
}
}
}
You need to use "Fast Enumeration" to parse the array's objects, and write each object to disk sequentially. First, you're going to need to add the UIImageView objects to the array instead of the UIImage property of the UIImageView, so you can recover the tag. So instead of writing
[self.array addObject:imageView.image];
It will be
[self.array addObject:imageView];
Try to follow along with my code. I inserted comments on each line to help.
-(void)applicationDidEnterBackground:(UIApplication *)application {
//Obtain the documents directory
NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainmask,YES) objectAtIndex:0];
//begin fast enumeration
//this is special to ObjC: it will iterate over any array one object at a time
//it's easier than using for (i=0;i<array.count;i++)
for (UIImageView *imageView in self.array) {
//get the imageView's tag to append to the filename
NSInteger tag = imageView.tag;
//get the image from the imageView;
UIImage *image = imageView.image;
//create a filename, in this case "ImageTAGNUM.png"
NSString *imageName = [NSString stringWithFormat:#"Image%i.png",tag];
//concatenate the docsDirectory and the filename
NSString *imagePath = [docsDir stringByAppendingPathComponent:imageName];
[UIImagePNGRepresentation(image) writeToFile:imagePath atomically:YES];
}
}
To load the images from disk, you'll have to look at your viewDidLoad method
-(void)viewDidLoad {
//get the contents of the docs directory
NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainmask,YES) objectAtIndex:0];
//Get the list of files from the file manager
NSArray *docFiles = [[NSFileManager defaultManager]contentsOfDirectoryAtPath:docsDir error:NULL]);
//use fast enumeration to iterate the list of files searching for .png extensions and load those
for (NSString *fileName in docFiles) {
//check to see if the file is a .png file
if ([fileName hasSuffix:#".png"]) {
NSString *fullPath = [docsDir stringByAppendingPathComponent:fileName];
UIImage *loadedImage = [UIImage imageWithContentsOfFile:fullPath];
//you'll have to sort out how to put these images in their proper place
if (!imageView1.image) {
imageView1.image = loadedImage;
} else {
imageView2.image = loadedImage;
}
}
}
}
Hope this helps
One thing you need to be aware of is that when an app enters the background it has about 5 seconds to clean up its act before it's suspended. The UIPNGRepresentation() function takes a significant amount of time and is not instantaneous. You should be aware of this. It would probably be better to write some of this code in other places and do it earlier than at app backgrounding. FWIW
You can use the [NSbundle Mainbundel] to store that images.
To get path
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
First, there's still a problem in your for loop.
for (UIImageView *imageView in self.array) {
NSInteger tag = self.imageView.tag;
UIImage *image = self.imageView.image;
// ...
}
Before you make any other changes, you must understand why. imageView is your for loop control variable, which changes on each iteration through the loop. self.imageView is a different thing. It is the first of the 10 imageViews attached to your viewController. Every time this loop cycles, it looks at the first imageView, and only the first.
As for why saving doesn't work, it's probably because the arrays elsewhere aren't working. Add some logging to make sure there's something in the array, and that it has as many elements as you expect.
-(IBAction)saveButtonPressed:(id)sender {
NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES) objectAtIndex:0];
// Log to make sure the views expected have previously been stored.
// If the array is empty, or shorter than expected, the problem is elsewhere.
NSLog(#"Image view array before saving = %#", self.array);
for (UIImageView *imageViewToSave in self.array) {
NSInteger tag = imageViewToSave.tag;
UIImage *image = imageViewToSave.image;
NSString *imageName = [NSString stringWithFormat:#"Image%i.png",tag];
NSString *imagePath = [docsDir stringByAppendingPathComponent:imageName];
// Log the image and path being saved. If either of these are nil, nothing will be written.
NSLog(#"Saving %# to %#", image, imagePath);
[UIImagePNGRepresentation(image) writeToFile:imagePath atomically:NO];
}
NSLog(#"Save Button Pressed");
}
I have such code
arrayWithImages = [[NSMutableArray alloc] init];
NSEnumerator *enumForNames = [arrayWithNames objectEnumerator];
NSEnumerator *enumForURLs = [arrayWithURLs objectEnumerator];
id objName, objURL;
while(objName = [enumForNames nextObject]) {
objURL = [enumForURLs nextObject];
UIImageView *anImage = nil;
[anImage setImageWithURL:[NSURL URLWithString:objURL]];
(...)
[arrayWithImages addObject:anImage];
}
And each time I got SIGABRT in line with "[arrayWithImages addObject:anImage];"
What's here wrong?
I don’t see an setImageWithURL method on UIImageView. Where is this from?
Is there any output from the SIGABRT crash?
Try this code:
// Download the image
NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:objURL]];
// Make an UIImage out of it
UIImage *anImage = [UIImage imageWithData:imageData];
// Create an image view with the image
UIImageView *imageView = [[UIImageView alloc] initWithImage:anImage];
// Check to make sure it exists
if (imageView != nil) {
// Add it to your array
[arrayWithImages addObject:imageView];
else {
NSLog(#"Image view is nil");
}
Note that you should download the images asynchronously to avoid hanging the loop. This blog post discussing asynchronous image downloading.
Also if you know that [enumForURLs nextObject]; will return an NSString (or even better, NSURL) you should assign objURL to type NSString (or NSURL).
I'm having this issue with some objective C code to load the images on a IKImageBrowserView.
I'm following the image browser example from apple, but I still fail at some point and Im guessing its memory management.
Here is some of the code:
/* Our datasource object */
#interface myImageObject : NSObject
{
NSString *_path;
}
#end
#implementation myImageObject
- (void)dealloc
{
[_path release];
[super dealloc];
}
/* our datasource object is just a filepath representation */
- (void)setPath:(NSString *)path
{
NSLog(#"setting path for %#",path);
if(_path != path)
{
[_path release];
_path = [path retain];
}
}
Now, It seems I'm properly retaining the path value within the object.
now on to the controller code:
-(IBAction)loadMosaicImages:(id)sender
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
NSArray *urls = [openFiles() retain];
NSInteger n;
n = [urls count];
NSURL *url = [urls objectAtIndex:0];
[self parsePathForImages:[url path]];
[urls release];
[pool drain];
}
- (void)updateDatasource
{
NSLog(#" UDS-> _importedImages length : %#",[_importedImages count]);
//-- update our datasource, add recently imported items
[_images addObjectsFromArray:_importedImages];
//-- empty our temporary array
[_importedImages removeAllObjects];
NSLog(#" UDS-> _images length : %#",[_images count]);
//-- reload the image browser and set needs display
[_imageBrowser reloadData];
}
-(void)parsePathForImages:(NSString *)path{
NSLog(#"Directory within thread method is %#",path);
NSArray *content = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:path error:nil];
myImageObject *p;
for(int i=0;i<content.count;i++)
{
// NSLog(#"%#",(NSString *)[content objectAtIndex:i]);
NSLog(#"Complete : %#",[path stringByAppendingPathComponent:(NSString *)[content objectAtIndex:i]]);
/* add a path to our temporary array */
p = [[myImageObject alloc] init];
[p setPath:[path stringByAppendingPathComponent:[content objectAtIndex:i]]];
[_importedImages addObject:p];
[p release];
}
[self updateDatasource];
}
and that's all the relevant code. _images and _importedImages are NSMutableArrays alloced and inited in the awake from nib method, and openFiles() is a static method that opens an NSOpenpanel and returns an NSArray of the paths.
the debug output for this does this:
Directory within thread method is /Users/cromestant/Code/images/
Complete : /Users/cromestant/Code/images/1.jpg
setting path for /Users/cromestant/Code/images/1.jpg
Complete : /Users/cromestant/Code/images/2.jpg
setting path for /Users/cromestant/Code/images/2.jpg
Complete : /Users/cromestant/Code/images/3.jpg
setting path for /Users/cromestant/Code/images/3.jpg
.
.
.
then stops crashes at the first line of the method updateDataSource, on the NSLog with an 'EXEC_BAD_ACCESS'so where am I going wrong with the memory management?
I seem to be creating an autoreleasePool so ht I have time to retain somewhere else, I release my objects.. I really don't have a clue where the problem could be.
thanks in advance.
Actually, I think your problem might not be memory management. It might be here:
NSLog(#" UDS-> _importedImages length : %#",[_importedImages count]);
It should be
NSLog(#" UDS-> _importedImages length : %d",[_importedImages count]);
because the count method returns an integer, not an object.
I am new to ObC and have a problem that i just cant fix. There may be other issues as well but the main issue is this:
Starting the app
Press button = load new view
In the new viewDidLoad i call another object/function and send a NSMutableArray
Process data and send back a NSMutableArray
App crash, see comment where. Most often when i go back and back again but sometimes the first time
As i am new to this i guess i do a lot of this wrong but could someone nice take a look at the code and give me some advice. I would assume i have problem with releasing something.
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#" ");
NSLog(#"viewDidLoad ");
NSLog(#" ");
NSLog(#">>Processing prepareGame<<");
NSMutableArray *propArray1 = [[NSMutableArray alloc] initWithObjects:#"9999", nil]; //Init with dummy numbers
AccessPropertiesFile *readMyProperties = [AccessPropertiesFile new]; //Init function call to read file
NSLog(#"Prepare to call readProperties");
propArray1 = [readMyProperties readPropertiesFile:propArray1];
NSLog(#"Back from readProperties:error after this");
/*
for (NSString *element in propArray1) {
NSLog(#"Elements in prop2Array; %#", element);
}
*/
[readMyProperties release];
[propArray1 release];
}
-(NSMutableArray *)readPropertiesFile:(NSMutableArray *)readDataArray {
NSLog(#"Processing readProperties");
// For error information
NSError *error;
//Prepare File Manager
NSString *filePath = [self dataFilePath];
NSFileManager *fileMgr;
fileMgr = [NSFileManager defaultManager];
NSArray *propertiesArray = [NSArray alloc]; //Alloc array
//Check from what module the call is coming from to ecide what to do
if ([fileMgr fileExistsAtPath: filePath] == NO) {
NSLog (#"File not found");
//File does not exists, this is the first time the game starts
//Set up default parameters
NSString *fileString =#"0\n30\n30\n10\n1\n1\n1\n2\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n";
// Write default parameters to file
[fileString writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:&error];
propertiesArray = [fileString componentsSeparatedByString:#"\n"]; // each line, adjust character for line endings
}
else { //File exists
NSLog (#"File exists");
NSString *fileString = [NSString stringWithContentsOfFile:filePath
encoding:NSUTF8StringEncoding error:nil]; // reads file into memory as an NSString
propertiesArray = [fileString componentsSeparatedByString:#"\n"]; // each line, adjust character for line endings
}
//Clean readDataArray
[readDataArray removeAllObjects];
//Populate return array
for (NSString *element in propertiesArray) {
//NSLog(#"Elements in propertiesArray; %#", element);
[readDataArray addObject:element];
}
NSLog(#"readDataArray: %#", readDataArray);
[propertiesArray release];
[readDataArray autorelease];
NSLog(#"returning from readProperties");
return readDataArray;
}
#end
You are over-releasing readDataArray (known as propArray1 in the method that didn't create it). You create it and autorelease it in your second method, then you release it again at the end of your first method (where it wasn't created).
I suggest you use Analyze feature that comes with latest XCode. It is a good feature that I always use to track if I forget to release or release too much.
I also spotted that you also over-release the propertiesArray because it contains the result from [fileString componentsSeparatedByString:], which will be autorelease according to Cocoa convention.