I 've never had problems with my app using AFNetworking, because I had like 20 imageview to show , but now my app crash because I want to set imagewithURL to 150 Imageviews, if I commented that line all is ok, this is my code:
for (int i=0; i< Array.count; i++) {
UIImageView *imgProd=[[UIImageView alloc] initWithFrame:CGRectMake(margenX, margenY, 220, 330)];
imgProd.contentMode = UIViewContentModeScaleAspectFill;
imgProd.clipsToBounds = YES;
[imgProd setTag:i];
// dispatch_async(dispatch_get_main_queue(), ^{
[imgProd setImageWithURL:[NSURL URLWithString: [Array objectAtIndex:i]]];
// });
imgProd.userInteractionEnabled = YES;
UITapGestureRecognizer *tap ... etc etc.
}
I put a dispatch_async, but is the same problem, please some advices!, thanks :)
You are creating 150 UIImageViews and are filling them up with imagedata which mess up your memory and crashes your app.
You should make a UITableView or UICollectionView and use the built in memory handler
dequeueReusableCellWithReuseIdentifier
, to show the images on the screen and reuse only one and the same UIImageView in the cell. Not create 150 uiimageviews that is, only one is needed.
Some fast googling got me to this tutorial:
https://www.youtube.com/watch?v=OBL8OJUWmsI
Gl !
Related
Pretty new to cocoa development and really stuck with probably a fundamental problem.
So in short, my app UI looks like a simple window with a nsslider at the bottom. What I need is to generate N images and place them, onto N nsviews in my app window.
What it does so far:
I'm clicking on the slider (holding it) and dragging it. While I'm dragging it nothing happens to my views (pictures are not generated). When I release the slider the pictures got generated and my view get filled with them.
What I want:
- I need the views to be filled with pictures as I'm moving the slider.
I figured out the little check box on the NSSlider properties, which is continuous, and I'm using it, but my image generator still doesn't do anything until I release the slider.
Here is my code:
// slider move action
- (IBAction)sliderMove:(id)sender
{
[self generateProcess:[_slider floatValue];
}
// generation process
- (void) generateProcess:(Float64) startPoint
{
// create an array of times for frames to display
NSMutableArray *stops = [[NSMutableArray alloc] init];
for (int j = 0; j < _numOfFramesToDisplay; j++)
{
CMTime time = CMTimeMakeWithSeconds(startPoint, 60000);
[stops addObject:[NSValue valueWithCMTime:time]];
_currentPosition = initialTime; // set the current position to the last frame displayed
startPoint+=0.04; // the step between frames is 0.04sec
}
__block CMTime lastTime = CMTimeMake(-1, 1);
__block int count = 0;
[_imageGenerator generateCGImagesAsynchronouslyForTimes:stops
completionHandler:^(CMTime requestedTime, CGImageRef image, CMTime actualTime,AVAssetImageGeneratorResult result, NSError *error)
{
if (result == AVAssetImageGeneratorSucceeded)
{
if (CMTimeCompare(actualTime, lastTime) != 0)
{
NSLog(#"new frame found");
lastTime = actualTime;
}
else
{
NSLog(#"skipping");
return;
}
// place the image onto the view
NSRect rect = CGRectMake((count+0.5) * 110, 500, 100, 100);
NSImageView *iView = [[NSImageView alloc] initWithFrame:rect];
[iView setImageScaling:NSScaleToFit];
NSImage *myImage = [[NSImage alloc] initWithCGImage:image size:(NSSize){50.0,50.0}];
[iView setImage:myImage];
[self.windowForSheet.contentView addSubview: iView];
[_viewsToRemove addObject:iView];
}
if (result == AVAssetImageGeneratorFailed)
{
NSLog(#"Failed with error: %#", [error localizedDescription]);
}
if (result == AVAssetImageGeneratorCancelled)
{
NSLog(#"Canceled");
}
count++;
}];
}
}
If you have any thoughts or ideas, please share with me, I will really appreciate it!
Thank you
In order to make your NSSlider continuous, open your window controller's XIB file in Interface Builder and click on the NSSlider. Then, open the Utilities area
select the Attributes Inspector
and check the "Continuous" checkbox
under the Control header. Once you've done this, your IBAction sliderMove: will be called as the slider is moved rather than once the mouse is released.
Note: Alternatively, with an
NSSlider *slider = //...
one can simply call
[slider setContinuous:YES];
Im pretty new to Cocoa development, and I probably do not clearly understand how ARC works.
My problem is that when I'm using NSImageView it is not getting deallocated as I want so the program is leaking memory.
__block CMTime lastTime = CMTimeMake(-1, 1);
__block int count = 0;
[_imageGenerator generateCGImagesAsynchronouslyForTimes:stops
completionHandler:^(CMTime requestedTime, CGImageRef image, CMTime actualTime,
AVAssetImageGeneratorResult result, NSError *error)
{
if (result == AVAssetImageGeneratorSucceeded)
{
if (CMTimeCompare(actualTime, lastTime) != 0)
{
NSLog(#"new frame found");
lastTime = actualTime;
}
else
{
NSLog(#"skipping");
return;
}
// place the image onto the view
NSRect rect = CGRectMake((count+0.5) * 110, 100, 100, 100);
// the problem is here!!! ImageView object gets allocated, but never released by the program even though I'm using ARC
NSImageView *imgV = [[NSImageView alloc] initWithFrame:rect];
[imgV setImageScaling:NSScaleToFit];
NSImage *myImage = [[NSImage alloc] initWithCGImage:image size:(NSSize){50.0,50.0}];
[imgV setImage:myImage];
[self.window.contentView addSubview: imgV];
}
if (result == AVAssetImageGeneratorFailed)
{
NSLog(#"Failed with error: %#", [error localizedDescription]);
}
if (result == AVAssetImageGeneratorCancelled)
{
NSLog(#"Canceled");
}
count++;
}];
Therefore, when I'm returning to this block again t generate new images and display them, everything works perfect except that my program memory use increases by the number of views got created.
If anyone can help me with this I would really appreciate it! Thank you!
Your problem is that you don't remove your subviews when you are generating new ones - make sure you remove your subviews before with something along those lines:
NSArray *viewsToRemove = [self.contentView subviews];
for (NSView *v in viewsToRemove) {
[v removeFromSuperview];
}
So your problem is not related to the usage of ARC actually. Each time you create a NSImageView and add it to contentView it is your responsability to remove them before adding a series of new ones. Note that adding those views to contentView will increment the ref count by one and removing them from the contentView will decrement the ref count by one leading to the memory usage for those views being freed by the system (because nothing else is retaining your views in btw).
Offending piece of code:
[self.window.contentView addSubview: imgV];
You've allocated an NSImageView. and keep adding it to the view. You never remove it, meaning the view is creating many references to different instances of the same object, all allocating their own piece of memory.
Solution: You'll need to keep track of the view, to make sure you can remove it later. Typically, I use class extensions.
For example:
#interface ClassName() {
NSImageView* m_imgV;
}
#end
....
// place the image onto the view
NSRect rect = CGRectMake((count+0.5) * 110, 100, 100, 100);
if (m_imgV) {
[m_imgV removeFromSuperView];
}
m_imgV = [[NSImageView alloc] initWithFrame:rect];
[m_imgV setImageScaling:NSScaleToFit];
NSImage *myImage = [[NSImage alloc] initWithCGImage:image size:(NSSize){50.0,50.0}];
[m_imgV setImage:myImage];
[self.window.contentView addSubview:m_imgV];
I was fighting with this problem for the whole day and finally found the way. For some reason the program wanted me to add a whole function which looks like:
// remove all the view from the superview
// and clean up a garbage array
-(void) killAllViews
{
for (NSImageView *iv in _viewsToRemove)
{
[iv removeFromSuperview];
}
[_viewsToRemove removeAllObjects]; // clean out the array
}
where _viewsToRemove is an array of NSImageViews which I'm filling every time my block is generating new images and adds them to the view.
Still don't understand why just adding the pure code from inside my killAllViews method somewhere into program couldn't solve the problem. Right now I'm basically doing the same, but just calling this method.
To get a sense of what I'm doing without posting pages of code... I have an NSOperation that I'm using to process files as they are added to a folder. In that NSOperation I'm using the NSNotificationCenter to send notifications to an NSView whenever a new job is started. The idea is, that I want to add a new subview to give me some information about the job that just started. The problem is I can't seem to get new subviews to draw. Here is what I have right now.
- (void)drawRect:(NSRect)dirtyRect
{
NSLog(#"Draw Count %i", [jobViewArray count]);
int i = 0;
while (i < [jobViewArray count]) {
[self addSubview:[jobViewArray objectAtIndex:i]];
}
}
and then further down:
-(void) newJobNotification: (NSNotification *) notification
{
if (!jobViewArray)
jobViewArray = [[NSMutableArray alloc] init];
++jobCount;
NSRect rect;
rect.size.width = 832;
rect.size.height = 120;
NSPoint point = { 0, ((jobCount * 120) - 120) };
rect.origin = point;
ProgressView *newJob = [[ProgressView alloc] initWithFrame:rect];
[jobViewArray addObject:newJob];
NSLog(#"Notice Count %i", [jobViewArray count]);
}
}
When I use my app to add a job, the notification is properly received by my NSView, the subview is properly added to the jobViewArray, but then when drawRect: gets called again my jobViewArray is empty. It's the first time I've tried to do something like this so I'm probably doing something completely wrong here... I guess that goes with out saying since it doesn't work huh?
You shouldn't be adding the subview to the view in drawRect:. When you receive the notification you should add the subviews there because the second time the notification comes around, you're going to add 2 subviews, then the next time 3 subviews and so one.
If you add the subview in the notification then you'll not need to mess around with the array.
I'm having a bit of trouble with an iPad app I'm creating. There is a simple image sequence/animation of about 80 frames at one point.
The code looks like this (this is a UIView subclass subclass):
- (id)init {
UIImage *theImage = [UIImage imageNamed:#"chart0075.jpg"];
// get the frame
CGRect lgeFrame = CGRectMake(20, 130, theImage.size.width, theImage.size.height);
// set the new frame
CGFloat newHeight = theImage.size.height/1.65;
CGFloat newWidth = theImage.size.width/1.65;
CGRect smlFrame = CGRectMake(480, 200, newWidth, newHeight);
self = [super initWithLargeFrame:lgeFrame smallFrame:smlFrame];
if(self){
// lets add the image as an image view
theImageView = [[UIImageView alloc] initWithImage:theImage];
[theImageView setFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
[theImageView setAutoresizingMask:UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight];
[self addSubview:theImageView];
// now we need to make an array of images for the image sequence
NSMutableArray *imageSeq = [NSMutableArray array];
for(int i = 1; i < 76; i++){
NSString *jpgnumber;
if(i<10){
jpgnumber = [NSString stringWithFormat:#"000%i",i];
}
else {
jpgnumber = [NSString stringWithFormat:#"00%i",i];
}
NSString *imageFile = [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:#"chart%#",jpgnumber] ofType:#"jpg"];
[imageSeq addObject:[UIImage imageWithContentsOfFile:imageFile]];
}
[theImageView setAnimationImages:imageSeq];
[theImageView setAnimationDuration:1.5];
[theImageView setAnimationRepeatCount:1];
}
return self;
}
Then on a reverse pinch gesture the image is supposed to animate. The first time I do this reverse pinch gesture it takes a few seconds to start the animation. And sometimes I get a memory warning level 1 and the app will crash.
Whats the problem here? Are 80 jpgs too much to keep in memory at once? They're well under 2mb big in total, so they surely shouldn't be filling up the ipad's memory right?
I've looked at it with the allocations tool which is suggesting that I have about 40kb in memory at the time of the animation, but then this goes back down to 0 during subsequent animations. (although the allocations tool does confuse me quite a bit).
Does anyone have any idea what's causing this? I can post more code or anything if necessary?
Thanks a lot :)
Your memory usage depends on how big the images are uncompressed. The width times the height time 4 will tell you the number of bytes the images will take each, multiply by the number of images to get the total.
My guess is you are on the edge of being over memory wise.
Run in Instruments with the VMTracker instrument to be sure. You should be looking at the Dirty Resident memory.
WWDC '10 and WWDC '09 both had great content on Instruments and memory usage analysis.
You are not releasing theImageView
[theImageView release]
I am relatively new to programming on the iPad and I was trying to put together a simple program. Basically, it's a children's book and I need the functionality of a comic book style (or photo) viewer, where people swipe to change "pages" (or images).
Each image is 1024x768. Currently, they are stored as JPGs because of the very large file sizes PNGs seem to produce. For this story, there are 28 pages.
I took a look at the PageControl example, implementing a UIScrollView. On initialization, I create a big enough scrollview area. Then as the user scrolls, I load in the previous and next images. Again, just like the example only without implementing the page control at the bottom.
The problem I am running into is a very slight pause in the animation when I am flipping. Once the images are loaded or cached, this doesn't happen. Now, I know the photo application doesn't do this and I'm not sure what is causing it.
Here is my code for the scrollViewDidScroll method. I keep up with the page number and it will only call the loadPageIntoScrollView when a page has changed - I was thinking that the insane number of calls it was making was causing the slight pause in animation, but it turned out not to be the case.
- (void) scrollViewDidScroll: (UIScrollView *) sender
{
CGFloat pageWidth = scrollView.frame.size.width;
int localPage = floor( (scrollView.contentOffset.x - pageWidth / 2 ) / pageWidth ) + 1;
if( localPage != currentPage )
{
currentPage = localPage;
[self loadPageIntoScrollView:localPage - 1];
[self loadPageIntoScrollView:localPage];
[self loadPageIntoScrollView:localPage + 1];
}
} // scrollViewDidScroll
And here is my loadPageIntoScrollView method. I'm only creating a UIImageView and loading an image into that - I don't see how that could be much "leaner". But somehow it's causing the pause. Again, it's not a HUGE pause, just one of those things you notice and is enough to make the scrolling look like it has a very. very slight hiccup.
Thank you in advance for any help you could provide.
- (void) loadPageIntoScrollView: (int)page
{
if( page < 0 || page >= kNumberOfPages )
return;
UIImageView *controller = [pages objectAtIndex:page];
NSLog( #"checking pages" );
if( (NSNull *)controller == [NSNull null] )
{
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
NSString *pageName = [[NSString alloc] initWithFormat:#"%d.jpg", page];
controller = [[UIImageView alloc]initWithImage:[UIImage imageNamed:pageName]];
[controller setUserInteractionEnabled:YES];
[controller addGestureRecognizer:singleTap];
[pages replaceObjectAtIndex:page withObject:controller];
[controller release];
} // if controller == null
// add the page to the scrollview
if( controller.superview == nil )
{
NSLog(#"superview was nil, adding page %d", page );
CGRect frame = scrollView.frame;
frame.origin.x = frame.size.width * page;
frame.origin.y = 0;
controller.frame = frame;
[scrollView addSubview:controller];
} // if
} // loadPageIntoScrollView
Since you say after an image is loaded in it no longer lags, I'd suspect that it is disk access that is causing your lag, but you should run your app through instruments to try to rule out cpu-spikes as well as evaluate file system usage. You may try to pre-load images to the left and right of whatever image you are on so that the user doesn't perceive as much lag.
First off, you should be able to use PNG's just fine. I have build several apps that do exactly what you are doing here, you can fit 3 1024 x 768 PNGs in memory without running out (but you can't do much more). You should also use PNG's as they are the preferred format for iOS as they are optimized when the app is bundled together during build.
The slight lag is caused by loading the image, in this line:
controller = [[UIImageView alloc]initWithImage:[UIImage imageNamed:pageName]];
What I usually do is load the images in a separate thread, using something like this:
[self performSelectorInBackground:#selector(loadPageIntoScrollView:) withObject:[NSNumber numberWithInt:localPage]];
Note that you need to put your localPage integer into a NSNumber object to pass it along, so don't forget to change your loadPageIntoScrollView: method:
- (void) loadPageIntoScrollView: (NSNumber *)pageNumber
{
int page = [pageNumber intValue];
....