I am trying to build up my app with the images thumbnails which I loaded from server. The images are in large number. So when I try to run in my iPod it crashes after loading some 50 to 60 images. And the crash is because of the memory leak that I came to know by testing my app with instruments. I have used imageViews and a button for each imageView, and I also released those objects. Here is my code that I have used in my app.
NSInteger result = [self loadedBlipCount] + (_feed.hasMore ? 1 : 0);
if (result == 0 && _emptyFeedCell)
result = 1;
int outer_count = result/3;
scroll_view.backgroundColor = [UIColor whiteColor];
scroll_view.delegate = self;
for (int i=0; i<outer_count; i++)
//if (i<outer_count)
{
xPos = 10;
for (int j=0; j<3; j++) {
_blipyy = [_feed blipAtIndex:count];
image_view = [[URLImageView alloc] initWithFrame:CGRectMake(xPos, yPos, 90, 90)];
image_view.tag = count_tag;
image_view.url = _blipyy.image_tab_images;
UIButton *img_butt = [[UIButton alloc] initWithFrame:CGRectMake(xPos, yPos, 90, 90)];
img_butt.tag = count_tag + 10000;
[img_butt addTarget:self action:#selector(image_tapped:) forControlEvents:UIControlEventTouchUpInside];
xPos = xPos + 95;
count = count + 1;
count_tag = count_tag + 1;
//count_1= count_1 +1;
[scroll_view addSubview:image_view];
[scroll_view addSubview:img_butt];
[image_view release];
[img_butt release];
//[image_view release];
}
// });
yPos = yPos + 95;
}
Please help me with this issue. Thanks in Advance!!
Instead of scroll View take UITableView and customize UITableViewCell with your own implementation and re use cells. It will work with out any memory issue.
Try SDWebImage - it's works perfect for all my projects and so easy to integrate and use!
https://github.com/rs/SDWebImage
This problem needs you to change your approach. It's important for you to use either UITableView(It'll help you handling memory issues). However, if you still want to go ahead and use UIImageView then I'd suggest you to use this AsyncImageView. To call this API:
ASyncImage *img_EventImag = alloc with frame;
NSURL *url = yourPhotoPath;
[img_EventImage loadImageFromURL:photoPath];
[self.view addSubView:img_EventImage]; // In your case you'll add in your TableViewCell.
It's same as using UIImageView. Easy and it does most of the things for you. AsyncImageView includes both a simple category on UIImageView for loading and displaying images asynchronously on iOS so that they do not lock up the UI, and a UIImageView subclass for more advanced features. AsyncImageView works with URLs so it can be used with either local or remote files.
Loaded/downloaded images are cached in memory and are automatically cleaned up in the event of a memory warning. The AsyncImageView operates independently of the UIImage cache, but by default any images located in the root of the application bundle will be stored in the UIImage cache instead, avoiding any duplication of cached images.
The library can also be used to load and cache images independently of a UIImageView as it provides direct access to the underlying loading and caching classes.
Related
In my viewDidLoad method of my iPhone app I have the following code:
zombie[i].animationImages = zombieImages;
zombie[i].animationDuration = 0.8/zombieSpeed[i];
zombie[i].animationRepeatCount = -1;
[zombie[i] startAnimating];
Later on in the app the following code is called:
[zombie[i] stopAnimating];
zombie[i] = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"zh.png"]];
zombie[i].animationImages = flyingZombieImages;
zombie[i].animationDuration = 0.8/zombieSpeed[i];
zombie[i].animationRepeatCount = -1;
[zombie[i] startAnimating];
This causes the app to crash, with EXC_BAD_ACCESS on the line zombie[i].animationImages = flyingZombieImages;
flyingZombieImages is initialized with the following code: (zombieImages is initialized the same way)
NSMutableArray *flyingZombieImages = [NSMutableArray array];
for (NSUInteger i=1; i <= 29; i++) {
NSString *imageName = [NSString stringWithFormat:#"flzom%d.png", i];
[flyingZombieImages addObject:[UIImage imageNamed:imageName]];
}
Why is this happening? Is there a workaround?
As Dima mentioned flyingZombieImages is likely not initialized properly, which is causing the crash. However, there is another problem as well when you create the new instances of UIImageView:
zombie[i] = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"zh.png"]];
At this point you already have a reference to the old UIImageView stored in this variable. You are losing the reference to it and most likely will leak its memory. You also would want to remove the old UIImageView from the view hierarchy and add the new one.
A better way is instead to use the original UIImageView and change its image by replacing this line with:
zombie[i].image = [UIImage imageNamed:#"zh.png"];
i have this scroll view, that I'm loading into him few images from URL.
the problem is that the scroll view don't show any of them until that all loaded.
i want to show every image the moment i finished loading her.
my code looks like this:
-(void)loadPhotosToLeftscroll{
for (int count = 0 ; count < [leftPhotoArray count]; count++) {
NSLog(#"nextPhotoHight: %f",nextLeftPhotoHight);
NSMutableDictionary *photoDict;
photoDict = [leftPhotoArray objectAtIndex:count];
float photoHight = [[photoDict objectForKey:#"photos_height"]floatValue];
float photoWide= [[photoDict objectForKey:#"photos_width"]floatValue];
NSString *photoPath = [photoDict objectForKey:#"photos_path"];
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString:photoPath]];
UIImage *image = [[UIImage alloc] initWithData:imageData];
UIImageView *photoView = [[UIImageView alloc]initWithFrame:CGRectMake(10 , nextLeftPhotoHight, photoWide, photoHight )];
[photoView setImage:image];
[photoView.layer setMasksToBounds:YES];
[photoView.layer setCornerRadius:6];
nextLeftPhotoHight = photoView.frame.size.height + photoView.frame.origin.y + 10;
[leftBlockScroll addSubview:photoView];
}
}
You better use a asynchronous way to do that.
Relative topic is NSURLConnection, UIImageView.
I have done something similar before.
1. Create a new model inherit to UIView
2. This model will have a UIImageView, NSData
3. When u init the model, pass in a URL
4. Use NSURLConnection to send out AsynchroizedRequest
5. By using NSURLConnection delegate, you will finally get the Data of the image
6. Init a UIImage with these data
7. Init The UIImageView with this Image
8. Add this imageview to this model or directly pointing this model to the imageview
Feel free to ask for more detail :)
I am currently trying to nest a UIWebView (among other elements) into a custom UITableViewCell subclass.
I need to dynamically determine the size of the cell (using heightForRowAtIndexPath) but for some reason when I do it like so, the height always gets printed as 0:
UIWebView* wv = [[[UIWebView alloc] init] autorelease];
[wv loadHTMLString:body baseURL:nil];
[wv setNeedsLayout]; //I don't think these are necessary but I tried anyway.
[wv setNeedsDisplay];
CGSize wvSize = [wv sizeThatFits:webViewBounds];
NSLog(#"WVHEIGHT %f", wvSize.height); //THIS IS WHERE IT PRINTS.
CGFloat retVal = 10.0f;
retVal += 50 > wvSize.height ? 50 : wvSize.height;
retVal += 2 + 15 + 10;
return retVal;
Now, if I do that exact same calculation using the cell.webView that I have access to in cellForRowAtIndexPath, it returns a non-zero value. However, I'd really like to avoid loading an entire cell just to figure out how tall it should be...
Additionally, UIWebView is very slow at rendering text (and it is unfortunately not negotiable that I use UIWebView), so I was wondering if there's a way to tell it to display the typical Apple "rotating gear" activity icon until it has its text fully loaded and ready to render.
I would recommend hiding each UIWebView until it is done loading, and showing a loading indicator instead. I would then make a dictionary with keys that match the tags, and for each entry in the dictionary, I would store the size of the UIWebView.
Make your controller conform to the UIWebViewDelegate protocol, and use the following code:
- (void)webViewDidFinishLoad:(UIWebView *)webView {
NSString *output = [webView stringByEvaluatingJavaScriptFromString:#"document.getElementById('this').offsetHeight;"];
[self.webViewHeights setValue:[output floatValue] forKey:[NSString stringWithFormat:#"%f", webView.tag]];
}
After that, add code to hide your loading view and display your UIWebView, then call a table reload. In your cell height method, just check the correct array element for your UIWebView height.
Edit:
It seems I left out the important part!
OK, so, to create non-visible UIWebViews, you just need to create them, but not actually add them to a view. For example, you could do something like this in your viewDidLoad method:
UIWebView *newWebView = [[UIWebView alloc] initWithFrame:newFrame];
[newWebView loadHTMLString:body baseURL:nil];
newWebView.tag = 1;
[self.webViewDictionary setObject:newWebView forKey:#"1"];
Then in your table code, say something like
NSString *tagString = [NSString stringWithFormat:#"%d", indexPath.row];
UIWebView *curWebView = [self.webViewDictionary objectForKey:tagString];
if (curWebView.loading == NO) {
CGRect newFrame = curWebView.frame;
newFrame.size.height = [self.webViewHeights objectForKey:tagString];
curWebView.frame = newFrame;
[cell addSubview:curWebView];
} else {
UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorStyleGray];
[cell addSubview:activityIndicator];
}
I don't think sizeThatFits: is what you want to use.
sizeThatFits:
Asks the view to calculate and return
the size that best fits its subviews.
Your webview does not have any subviews, only HTML.
UIWebView has no init method of its own, so you probably should use initWithFrame: (from the UIView superclass) to set the size directly. You can set it to the size you want, which is the size of the tableView cell in this case.
I've read a lot of UIScrollView with UIImageView threads here or other googled pages. But I still cannot get the problem I'm confronting. I'm having a cold right now. Hope I can still make it clear, lol. Here is the problem:
I'm building one app which mainly uses UIScrollView to display a few images. Here the amount counts, not the size, which is averagely 100KB(I even converted PNG to jpg, not sure whether it helps or not). With no more than 10 images, my app crashes with memory warning. This is the first time I encounter memory issue, which surprised me as the compiled app is less than 10MB.
At the very beginning, I load all the images on launch, looping all names of image files and do
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:imgName]];
[scrollview addSubview:imageView];
[imageView release];
If I'm right, I think after launch, all the images are in memory, right? But the funny thing here is, the app could launch without any problem(at most a level 1 memory warning). After I scroll a few images, it crashed. I checked leaks for sure and also allocations. No leak and allocation almost had no change during scrolling.
So, is there something special done by imageNamed rather than cache?
And then, yes, I turned to lazy load.
For fear of checking page and loading images on demand might jerk the scrolling(which was proved true), I used a thread which runs a loop to check offset of the scroll view and load/unload images.
I subclassed UIImageView by remembering the image name. It also contains loadImage and unloadImage which will be executed on that thread.
- (void)loadImage {
/if ([self.subviews count] == 0) {
UIImageView iv = [[UIImageView alloc] initWithImage:[UIImage imageNamed:self.imageName]];
[self performSelectorOnMainThread:#selector(renderImage:) withObject:iv waitUntilDone:NO];
//[self addSubview:iv];
[iv release];
}*/
if (self.image == nil) {
//UIImage *img = [UIImage imageNamed:self.imageName];
UIImage *img = [[UIImage alloc] initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[self.imageName stringByDeletingPathExtension] ofType:[self.imageName pathExtension]]];
// image must be set on main thread as UI rendering is main thread's responsibility
[self performSelectorOnMainThread:#selector(renderImage:) withObject:img waitUntilDone:NO];
[img release];
}
}
// render image on main thread
- (void)renderImage:(UIImage*)iv {
//[self addSubview:iv];
self.image = iv;
}
(void)unloadImage {
self.image = nil;
//[(UIView*)[self.subviews lastObject] removeFromSuperview];
}
You can see the commented code that I've played with.
In unloadImage, if I write [self.image release], then I get EXC_BAD_ACCESS, which is unexpected, as I think alloc and release are matched here.
The app still crashes with no leak. The initWithContentsOfFile version even crashed earlier than imageNamed version, and made the scrolling not that smooth.
I run the app on device. By checking allocations, I found imageNamed version used much less memory than initWithContentsOfFile version, though they both crash. Instruments also showed that the allocated images were 2,3 or 4, which indicated the lazy load did do his job.
I checked PhotoScroller of WWDC2010, but I don't think it solvs my problem. There is no zooming or huge picture involved.
Anybody helps! Thank you in advance.
The crash log says nothing. The app crashes mostly after memory warning level = 2. And if run on simulator, there will be no problem.
It doesn't matter which format do you use for your images. They're converted to bitmaps when you display them.
I'd suggest to use the technique similar to that one which is used by UITableView (hide the image and free the memory it uses when it disappears from the screen and instantiate the image only when you need to show it).
As an alternate way – if you need to show these images in a grid – you might take a look to a CATiledLayer.
Anyhow, loading all the images to the memory is not the best idea :)
You can load all the images to an array. And you can design a view having one image view and try the below code:
array name: examplearray and view name :exampleview
-(void)updateImagesInScrollView
{
int cnt = [examplearray count];
for(int j=0; j< cnt; ++j)
{
NSArray *nibContents = [[NSBundle mainBundle] loadNibNamed:#"exampleview"
owner:self
options:nil];
UIView *myView = [nibContents objectAtIndex:0];
exampleview * rview= (exampleview *)myView;
/* you can get your iamge from the array and set the image*/
rview.imageview.image = yourimage;
/*adding the view to your scrollview*/
[self.ScrollView addSubview:rview];
}
/* you need to set the content size of the scroll view */
self.ScrollView.contentSize = CGSizeMake(X, self.mHorizontalScrollView.contentSize.height);
}
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.