Want to check if image0.png, image1.png, image2.png , image3.png, image4.png really exist.
for (int i = 0; i<=61; i++) {
NSString *imageName = [NSString stringWithFormat:#"image%d.png", i];
UIImage *image = [UIImage imageNamed:imageName];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
UIImageWriteToSavedPhotosAlbum(imageView.image, self, #selector(image: didFinishSavingWithError:contextInfo:), nil);
How to write NSLog statement to check if image0.png, image1.png, image2.png , image3.png, image4.png really exist. Every time it is saving only image0.png image.
Thanks for help.
You still can use NSFileManager's fileExistsAtPath method to check whether the file does really exist or not.
[UIImage imageNamed:] loads the image from the application bundle. So, if the file is already is the bundle and has right name as what you're invoking, then it should have been loaded. Try deleting the application from your device/simulator and reload it again. Also, make sure that all of your bitmaps are copied to the bundle by checking the "Copy Bundle Resources" build phase of your target.
Another remark: it is useless to load the UIImage into a UIImageView before saving it to the library, unless you need that for some other processing... So this line of code may be redundant:
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
And the last line will become:
UIImageWriteToSavedPhotosAlbum(image, self, #selector(image: didFinishSavingWithError:contextInfo:), nil);
Hope this helps ;)
Related
App is crashing with error _NSCFConstantString CGImage]: unrecognized selector sent to instance
when trying app with this code to save image to photo album
int currentimage = _imageScrollView.contentOffset.y / [pictures count];
UIImage *imageToShow = [pictures objectAtIndex:currentimage];
UIImageWriteToSavedPhotosAlbum(imageToShow, self, #selector(image: didFinishSavingWithError:contextInfo:), nil);
By the information that you gave in the comments, you are using an UIImage reference ("imageToShow") that is pointing to a NSString (element from the array), and that is why when imageToShow receive the CGImage selector, crashes.
To solve this problem, you have to put UIImage references to UIImage objects in the array.
UIImage *image0 = [UIImage imageWithContentsOfFile:"image0FullPath.png"];
UIImage *image1 = [UIImage imageWithContentsOfFile:"image1FullPath.png"];
pictures = [[NSArray alloc] initWithObjects:image0, image1, nil];
If the images are in the mainbundle, you can use imageNamed instead of imageWithContentsOfFile. imageNamed receive as input only the name of the file, and search for it inside the mainbundle. imageWithContentsOfFile needs the full path.
Good Luck!
I m loading lots of rather large images in my viewcontroller, using
NSUInteger nimages = 0;
for (; ; nimages++) {
NSString *nameOfImage_ = #"someName";
NSString *imageName = [NSString stringWithFormat:#"%#%d.jpg", nameOfImage_, (nimages + 1)];
image = [UIImage imageNamed:imageName];
if (image == nil) {
break;
}
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
//some other stuff....
[imageView release];
}
the usual unloading occurs in - (void)viewDidUnload and - (void)dealloc
with self.image = nil; and [image release];
It seems after a few "loading" and "unloading" the cache still grows to the point of no return!!
:)
and the app crashes...
any ideas??? how do i empty my cache? and where?
thanks
EDIT:
ok this is what i was doing wrong.
Apparently this piece of code fixes the whole caching problem:
image = [[UIImage imageNamed:imageName] autorelease];
with autorelease being the key here.
thanks for the replies...
Thank you all for your suggestions.
Solution:
Used ARC and imageWithContentsOffFile to initialize the Images.
image = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:imageName ofType:nil]];
And Yes, imageNamed is only good for... well for nothing big...
image = [[UIImage imageNamed:imageName] autorelease];
This is incorrect. In keeping with the memory management rules, you shouldn't be releasing (or autoreleasing) the image because you didn't allocate or retain it. "imageNamed" doesn't contain "alloc", "new", "copy", or "retain".
As some of the other answers explain, you should load your images with a different method if you want more control over the memory they use.
imageNamed is an awful way to load images in reality, it never releases loaded images unless forced and keeps them in the cache forever. You should implement your own, more intelligent cache. A simple NSMutableDictionary gives the same functionality but with more flexibility.
For a more in-depth discussion you can read this: http://www.alexcurylo.com/blog/2009/01/13/imagenamed-is-evil/
Use another method to initialize you image. imageNamed caches.
Instead of using using imageNamed you can use imageWithContentsOfFile:
Or check this article
link 0
link 1
I'm trying to use a url as a UIImage in the OpenFlow API.
NSString *imageUrl = [[[newsEntries objectAtIndex:0] objectForKey: #"still"] retain];
NSURL *url2 = [NSURL URLWithString:imageUrl];
NSData *photoData = [NSData dataWithContentsOfURL:url2];
UIImage *imageUI = [UIImage imageWithData:photoData]
UIImageView *myImage = [UIImageView initWithFrame:imageUI];
[(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:myImage]];
[imageUr release];
[(AFOpenFlowView *)self.view setNumberOfImages:3];
I have tried it like this, but no success. The only way I got this API working was using the imageNamed type. The initwithData has no success.
So how can I change this NSString to finally become a imageNamed method?
A UIImageView is different from a UIImage.
Change this line: [(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:myImage]];
To this: [(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:imageUI]];
and it should work.
You have several significant errors here. It appears that you may need to read about C/Objective-C and types.
It sounds like you are asserting that, specifically, the line
UIImage *imageUI = [UIImage imageWithData:photoData]
is not working. The code up to that point actually looks okay (though it is not necessary to retain and then release the imageUrl variable.
Once you have created your UIImage, you should be able to pass it directly to your AFOpenFlowView:
[(AFOpenFlowView*)self.view setImage:imageUI forIndex:0];
The line
UIImageView *myImage = [UIImageView initWithFrame:imageUI];
has two errors (and is unnecessary anyway). First, -initWithFrame takes a CGRect as its argument, not a UIImage. UIImageView does have an initialization method -initWithImage, which is probably what you intended. But either way, methods that start with "init" are instance methods, not class methods, so you have to call them on actual instances of a UIImageView, like this:
UIImageView *myImage = [[UIImageView alloc] initWithImage:imageUI];
Note that this will leak memory unless you autorelease or release it.
The following line, you correctly try to give a UIImage to your AFOpenFlowView, but you attempt to create that UIImage by passing a UIImageView to the +imageNamed method. +imageNamed takes an NSString that contains the name of the image, and passing anything else to it won't work.
You must always be aware of what kind of object a method is expecting to receive, and make sure you find some way to give it that kind of thing.
Probably what you are looking for here is something like this:
NSString *imageUrl = [[newsEntries objectAtIndex:0] objectForKey: #"still"];
NSString *imageName = [imageUrl lastPathComponent];
[(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:imageName]];
can I check if downloaded image is corrupt or not before saving it into my document directory?
if yes then please tell me how?
thank you
UIImage *im = [[UIImage alloc] initWithData:YourNSData];
UIImageView *imview;
// test to see if the image was successfully created
if (im){
imview = [[UIImageView alloc] initWithImage:im];
}
Hope this helps
You could try to load the NSData object in a UIIImage with the initData. Then check if the return UIImage object is nil.
This is not full proof methods, but should work.
Im developing an app for an iPhone and I found that the following code is causing the memory allocation to increment.
-(UIImage *)createRecipeCardImage:(Process *)objectTBD atIndex:(int)indx
{
[objectTBD retain];
// bringing the image for the background
UIImage *rCard = [UIImage imageNamed:#"card_bg.png"];
CGRect frame = CGRectMake(00.0f, 80.0f, 330.0f, 330.0f);
// creating he UIImage view to contain the recipe's data
UIImageView *imageView = [[UIImageView alloc] initWithFrame:frame];
imageView.image = rCard;
[rCard release];
imageView.userInteractionEnabled = YES;
float titleLabelWidth = 150.0;
float leftGutter = 5.0;
float titleYPos = 25.0;
float space = 3.0;
float leftYPos = 0;
// locating Title label
float currentHeight = [self calculateHeightOfTextFromWidth:objectTBD.Title :titleFont :titleLabelWidth :UILineBreakModeWordWrap];
UILabel *cardTitle = [[UILabel alloc]initWithFrame:CGRectMake(leftGutter, titleYPos, titleLabelWidth, currentHeight)];
cardTitle.lineBreakMode = UILineBreakModeWordWrap;
cardTitle.numberOfLines = 0;
cardTitle.font = titleFont;
cardTitle.text = objectTBD.Title;
cardTitle.backgroundColor = [UIColor clearColor];
[imageView addSubview:cardTitle];
[cardTitle release];
leftYPos = titleYPos + currentHeight + space;
// locating brown line
UIView *brownLine = [[UIView alloc] initWithFrame:CGRectMake(5.0, leftYPos, 150.0, 2.0)];
brownLine.backgroundColor = [UIColor colorWithRed:0.647 green:0.341 blue:0.122 alpha:1.0];
[imageView addSubview:brownLine];
[brownLine release];
leftYPos = leftYPos + 2 + space + space + space;
// creating the imageView to place the image
UIImageView *processPhoto = [[UIImageView alloc] initWithFrame:CGRectMake(leftGutter, leftYPos, 150, 150)];
if((uniqueIndex == indx) && (uniqueImg.imageData != nil))
{
if([uniqueImg.rcpIden isEqualToString:objectTBD.iden])
{
objectTBD.imageData = [NSString stringWithFormat:#"%#", uniqueImg.imageData];
[recipesFound replaceObjectAtIndex:indx withObject:objectTBD];
NSData * imageData = [NSData dataFromBase64String:objectTBD.imageData];
UIImage *rcpImage = [[UIImage alloc] initWithData:imageData];
[imageData release];
processPhoto.image = rcpImage;
[rcpImage release];
}
}
else if(objectTBD.imageData != nil)
{
NSData * imageData = [NSData dataFromBase64String:objectTBD.imageData];
UIImage *rcpImage = [[UIImage alloc] initWithData:imageData];
processPhoto.image = rcpImage;
[rcpImage release];
[decodedBigImageDataPointers addObject:imageData];
}
else
{
UIImage * rcpImage = [UIImage imageNamed:#"default_recipe_img.png"];
processPhoto.image = rcpImage;
[rcpImage release];
}
NSlog(#" Process Photo Retain Count %i", [processPhoto retainCount]); // this prints a 1
[imageView addSubview:processPhoto];
NSlog(#" Process Photo Retain Count %i", [processPhoto retainCount]); // this prints a 2!!!!
//[processPhoto release]; // this line causes an error :(
// converting the UIImageView into a UIImage
UIGraphicsBeginImageContext(imageView.bounds.size);
[imageView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[objectTBD release];
for(UIView *eachSubview in imageView.subviews)
{
[eachSubview removeFromSuperview];
NSLog(#"each subview retainCount %i despues", [eachSubview retainCount]);
// here I find that the processPhoto view has a retain count of 2 (all other views have their retain count in 1)
}
return viewImage;
}
When I checked at the instruments object allocation I found that the "GeneralBlock-9216" growing up.
Breaking down the row I found that every time I call this code, one instance of:
2 0x5083800 00:18.534 ImageIO initImageJPEG
is being allocated. Checking the call stack, the following line is highlighted:
UIImage * objImage = [UIImage imageWithData:imageData];
Any help to find what the error is?
As TechZen said, the imageWithXXX: methods cache the image inside of them while you run the program (though you release the instances after using). I recommend initWithXXX: and release API sets instead of imageWithXXX:.
Well, if you embed several debug log on your source code, check how many times is it called, and check the retain count of the instances.
As far as I can explain, that is all.
I hope you will solve the problem.
Does anyone have an answer for this? It's tearing me apart trying to figure out why this image information keeps lingering. I've tried every solution.
The situation:
Images get downloaded and stored to the device, then loaded with imageWithContentsOfFile (or even initWithContentsOfFile, which doesn't help either). When the view goes away, the images don't, but they don't show up as leaks, they're just this initImageJPEG Malloc 9.00 KB that never goes away and keeps ramping up.
UPDATE: I believe I've figured this out: Check to make sure everything is actually getting dealloc'd when you're releasing whatever the parents (and/or grandparents) and etc of the images are. If the parents don't get deallocated, they never let go of their children images, and whatever data was in those images sticks around. So check retain counts of parent objects and make sure that everything's going away all the way up whenever you release the view at the top.
A good way to check for this is to put NSLogs into custom classes' dealloc methods. If they never show up, that object isn't going away, even though the reference to it might, and it (and whatever its subviews and properties are) will never ever disappear. In the case of images, this means a pretty sizable allocation every time that object is generated and never deallocated. It might not show up in leaks, especially if the parent of the topmost object you're thinking you're releasing but actually aren't persists and doesn't itself ever deallocate.
I hope this helps. It'll be useful to take some time to read through your code with a fine-toothed comb to make sure you're allocating and releasing things properly. (Search for "alloc]", start at the top of the file, and work your way down to make sure you're releasing and that the release isn't inside of some if() or something.)
Also, running "Build and Analyze" might lock up your machine for a bit, but its results can be really helpful.
Good luck!
I think you're seeing UIImage cacheing images. There used there used to be a method something like initWithData:cache that let you turn the cacheing off. Now I think the system always caches the images automatically behind the scenes even after you've deallocted the specific instances.
I don't think its an error on your part. I think it's the system keeping data around in the OpenGl subsystem. Unless it causes a major leak, I don't think it is a problem.