UIImageView is not always shown - ios

I'm debugging a problem with an imageView not being shown.
imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:imageName]];
NSLog(#"imageView right after initialization is: %#", imageView);
imageView.frame = CGRectMake(2, 0, 316, 45);
imageView.layer.zPosition = zPos;
NSLog(#"imageView after running the setters: %#", imageView);
[self.view addSubview:imageView];
The weird part is that sometimes the imageView gets displayed, sometimes it's not (about 75% of the time it's displayed).
imageView is not accessed anywhere except the code above.
What I noticed is that when the imageView is not displayed, the first log statement shows that:
imageView right after initialization is: <UIImageView: 0x9eaa760;
frame = (0 0; 0 0); userInteractionEnabled = NO; layer = <CALayer:
0x9ec04a0>>
When the image view is displayed:
imageView right after initialization is: <UIImageView: 0xaa61ad0;
frame = (0 0; 644 88); opaque = NO; userInteractionEnabled = NO; layer
= <CALayer: 0xaa61330&rt;&rt;
EDITED:
I ran tens of tests, the imageView always behaves the same: when it is not shown, the initial frame is (0 0; 0 0). When it's not, it's always some other value.
P.S. I'm not using ARC.

In your log of the UIImageView it show frame = (0 0; 0 0); This means that the view will not be shown since it has a height and width of 0. Which indicates that the image has no size or is nil.
The cause of this is most probably because the image your are trying to load is not found:
You should check wether the image is found or not:
UIImage *image = [UIImage imageNamed:imageName];
if (!image) {
NSLog(#"Image could not be found: %#", imageName);
}
imageView = [[UIImageView alloc] initWithImage:image];
Meaning that even if you change the frame you will still see nothing since there is no image loaded.

Why don't you set the frame first and set the image next?
imageView = [UIImageView alloc]initWithFrame:CGRectMake(0,0,35,35)];
[imageView setImage:[UIImage imageNamed:#"img.png"]];

In addition to rckoenes answer you must always check if the image exists within your bundle path first:
NSFileManager *fileManager = [NSFileManager defaultManager];
NSString *documentsDirectory
= [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)
objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:imageName];
if([fileManager fileExistsAtPath:path])
{
UIImage *image = [UIImage imageNamed:imageName];
if (!image) {
NSLog(#"Image could not be found: %#", imageName);
}
imageView = [[UIImageView alloc] initWithImage:image];
} else {
NSLog(#"%# is not included in the app file bundle!", imageName);
}
that way you'll know if the problem is b/c you don't have the file in the first place.. or b/c there is something wrong with file that prevents iOS from loading it.

Related

IOS UIImageView in cell has wrong size

I'm trying to replace an Image from an URL if it exists.
The problem seems to be that I can't set the size of my UIImageView.
My Code looks like this:
UIImageView *partnerIcon = (UIImageView*)[cell viewWithTag:0];
NSURL *imageUrl = [NSURL URLWithString:[[#"http://www.fitpas.ch/coreapp/resources/images/center/" stringByAppendingString:[[result objectAtIndex:indexPath.row] objectForKey:#"cid"]] stringByAppendingString:#".jpg"]];
UIImage* partnerImage = [UIImage imageWithData: [NSData dataWithContentsOfURL: imageUrl]];
if (partnerImage != nil) {
dispatch_async(dispatch_get_main_queue(), ^{
//change image
partnerIcon.image = partnerImage;
partnerIcon.contentMode = UIViewContentModeScaleToFill;
});
}
This results in:
In the Image above the last row partnerImage is nil and that shows how it should be.
I tried to scale the UIImage with
partnerIcon.image = [UIImage imageWithCGImage:partnerImage.CGImage
scale:1/100 orientation:partnerImage.imageOrientation];
but this won't change anything.
I also tried to set to change the dimension of the UIImageView with:
partnerIcon.bounds = CGRectMake(0, 0, 50, 50);
and also
partnerIcon.frame = CGRectMake(0, 0, 50, 50);
but this isn't working either.
Set an explicit width and height constraint on the image view. If you don't do this then the content hugging and compression values will be used across all of the views to decide how big each should be based on the content size.

NSMutableArray creates issue for images

I have an array with dictionaries in it. Each dictionary contains UIImage & String values.
But when I try to delete object using
[arr removeObjectAtIndex:button.tag];
then it just decreases the count but image (Object) is not deleted.
So, my Images are overlapping when try to delete.
It also creates problem when I try to add objects in the array
[arr insertObject:dict atIndex:0];
so, I used
[_postObj.arr_images addObject:dict]; instead of insertObject
Help me to solve this
Objects use reference counting and both NSMutableArray and UIImageView will retain the UIImage object.
This means that removing it from the array will not automatically remove it from the UIImageView and you must remove it from both explicitly:
[arr removeObjectAtIndex:button.tag];
_imageView.image = nil;
Problem is in your frame setting of UIImageView. Please try using below code (not tested by myself) and see if this fixes the issue for you. Basically, I am adjusting X position of images based on previous image's width.
CGFloat imageXM = 5.0;
CGFloat imageXPos = 0;
for (UIImage *image in arr_images) {
CGRect imageFrame = CGRectMake(imageXPos + imageXM, 0.0, image.size.width, image.size.height);
imageXPos = imageXPos + image.size.width;
UIImageView *imageView = [[UIImageView alloc] initWithFrame:imageFrame];
imageView.contentMode = UIViewContentModeScaleAspectFit;
imageView.image = image;
[scl addSubview:imageView];
}
As in your code
[picker dismissViewControllerAnimated:YES completion:^{
[arr_images insertObject:chosenImage atIndex:0];
[self scrollImages_Setup2];
}];
[arr_images insertObject:chosenImage atIndex:0]; that means you need only one image to display on scroll view. Then why you take a loop:
-(void)scrollImages_Setup2
{
for (int k=0; k<arr_images.count; k++) {
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake((CGRectGetWidth(scl.frame) * k) + CGRectGetWidth(scl.frame), 0, CGRectGetWidth(scl.frame), CGRectGetHeight(scl.frame))];
imageView.contentMode = UIViewContentModeScaleAspectFit;
imageView.image=[arr_images objectAtIndex:k] ;
[scl addSubview:imageView];
}
scl.contentSize = CGSizeMake((CGRectGetWidth(scl.frame) * arr_images.count)+CGRectGetWidth(scl.frame), CGRectGetHeight(scl.frame));
}
You just right the code only for display the Image. you don't need to scroll view for displaying only one image. I think you are not clear what you want.
Your problem regarding the overwriting the images because of loop. so remove the loop, when you display a single image. Please remove the scrollview contentSize, because image_array will increase, when you add the multiple images in array and size width will be large. so remove arr_images.count as well.

iOS UIImageView memory not getting deallocated on ARC

I want to animate an image view in circular path and on click of image that image view need to change the new image. My problem is the images i allocated to the image view is not deallocated. And app receives memory warning and crashed. I surfed and tried lot of solutions for this problem but no use. In my case i need to create all ui components from Objective c class. Here am posting the code for creating image view and animation.
#autoreleasepool {
for(int i= 0 ; i < categories.count; i++)
{
NSString *categoryImage = [NSString stringWithFormat:#"%#_%ld.png",[categories objectAtIndex:i],(long)rating];
if (paginationClicked) {
if([selectedCategories containsObject:[categories objectAtIndex:i]]){
categoryImage = [NSString stringWithFormat:#"sel_%#",categoryImage];
}
}
UIImageView *imageView = [[UIImageView alloc] init];
imageView.image = [self.mySprites objectForKey:categoryImage];
imageView.contentMode = UIViewContentModeScaleAspectFit;
imageView.clipsToBounds = NO;
[imageView sizeToFit];
imageView.accessibilityHint = [categories objectAtIndex:i];
// imageView.frame = CGRectMake(location.x+sin(M_PI/2.5)*(self.view.frame.size.width*1.5),location.y+cos(M_PI/2.5)*(self.view.frame.size.width*1.5) , 150, 150);
imageView.userInteractionEnabled = YES;
imageView.multipleTouchEnabled = YES;
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(categoryTapGestureCaptured:)];
singleTap.numberOfTapsRequired = 1;
[imageView addGestureRecognizer:singleTap];
[categoryView addSubview:imageView];
CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:#"position"];
UIBezierPath *path = [UIBezierPath bezierPath];
[path addArcWithCenter:location
radius:self.view.frame.size.width*1.5
startAngle:0.8
endAngle:-0.3+(0.1*(i+1))
clockwise:NO];
animation.path = path.CGPath;
imageView.center = path.currentPoint;
animation.fillMode = kCAFillModeForwards;
animation.removedOnCompletion = NO;
animation.duration = 1+0.25*i;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
// Apply it
[imageView.layer addAnimation:animation forKey:#"animation.trash"];
}
}
And this is the code to change the image on click.
for (UIImageView *subview in subviews) {
NSString *key = [NSString stringWithFormat:#"%#_%ld.png",subview.accessibilityHint,(long)rating];
if ([SelectedCategory isEqualToString:subview.accessibilityHint]) {
NSString *tempSubCategory = [categoryObj objectForKey:SelectedCategory];
if([selectedCategories containsObject:SelectedCategory]){
subview.image = [self.mySprites objectForKey:key];
[selectedCategories removeObject:SelectedCategory];
if (tempSubCategory.length != 0) {
subCategoriesAvailable = subCategoriesAvailable-1;
}
[self showNoPagination:subCategoriesAvailable+2];
}else{
if(selectedCategories.count != 2){
key = [NSString stringWithFormat:#"sel_%#",key];
subview.image = [self.mySprites objectForKey:key];
[selectedCategories addObject:SelectedCategory];
if ([SelectedCategory isEqualToString:#"Other"]) {
[self showCommentDialog];
}else{
if (tempSubCategory.length != 0) {
subCategoriesAvailable = subCategoriesAvailable+1;
}
[self showNoPagination:subCategoriesAvailable+2];
}
}
}
[self disableCategories];
break;
}
}
And i don't know what am doing wrong here. I tried nullifying on for loop but no use.
Code which i used for removing the image view
UIView *categoryView = [self.view viewWithTag:500];
NSArray *subviews = [categoryView subviews];
for (UIImageView *subview in subviews) {
if(![selectedCategories containsObject:subview.accessibilityHint]){
[subview removeFromSuperview];
subview.image = Nil;
}
}
Adding sprite reader code for reference
#import "UIImage+Sprite.h"
#import "XMLReader.h"
#implementation UIImage (Sprite)
+ (NSDictionary*)spritesWithContentsOfFile:(NSString*)filename
{
CGFloat scale = [UIScreen mainScreen].scale;
NSString* file = [filename stringByDeletingPathExtension];
if ([[UIScreen mainScreen] respondsToSelector:#selector(displayLinkWithTarget:selector:)] &&
(scale == 2.0))
{
file = [NSString stringWithFormat:#"%##2x", file];
}
NSString* extension = [filename pathExtension];
NSData* data = [NSData dataWithContentsOfFile:[NSString stringWithFormat:#"%#.%#", file,extension]];
NSError* error = nil;
NSDictionary* xmlDictionary = [XMLReader dictionaryForXMLData:data error:&error];
NSDictionary* xmlTextureAtlas = [xmlDictionary objectForKey:#"TextureAtlas"];
UIImage* image = [UIImage imageWithContentsOfFile:[NSString stringWithFormat:#"%#.%#", file,[[xmlTextureAtlas objectForKey:#"imagePath"]pathExtension]]];
CGSize size = CGSizeMake([[xmlTextureAtlas objectForKey:#"width"] integerValue],
[[xmlTextureAtlas objectForKey:#"height"] integerValue]);
if (!image || CGSizeEqualToSize(size, CGSizeZero)) return nil;
CGImageRef spriteSheet = [image CGImage];
NSMutableDictionary* tempDictionary = [[NSMutableDictionary alloc] init];
NSArray* xmlSprites = [xmlTextureAtlas objectForKey:#"sprite"];
for (NSDictionary* xmlSprite in xmlSprites)
{
CGRect unscaledRect = CGRectMake([[xmlSprite objectForKey:#"x"] integerValue],
[[xmlSprite objectForKey:#"y"] integerValue],
[[xmlSprite objectForKey:#"w"] integerValue],
[[xmlSprite objectForKey:#"h"] integerValue]);
CGImageRef sprite = CGImageCreateWithImageInRect(spriteSheet, unscaledRect);
// If this is a #2x image it is twice as big as it should be.
// Take care to consider the scale factor here.
[tempDictionary setObject:[UIImage imageWithCGImage:sprite scale:scale orientation:UIImageOrientationUp] forKey:[xmlSprite objectForKey:#"n"]];
CGImageRelease(sprite);
}
return [NSDictionary dictionaryWithDictionary:tempDictionary];
}
#end
Please help me to resolve this. Thanks in advance.
It looks like all the images are being retained by the dictionary(assumption) self.mySprites, as you are loading them with the call imageView.image = [self.mySprites objectForKey:categoryImage];
If you loaded the images into the dictionary with +[UIImage imageNamed:], then the dictionary initially contains only the compressed png images. Images are decompressed from png to bitmap as they are rendered to the screen, and these decompressed images use a large amount of RAM (that's the memory usage you're seeing labeled "ImageIO_PNG_Data"). If the dictionary is retaining them, then the memory will grow every time you render a new one to the screen, as the decompressed data is held inside the UIImage object retained by the dictionary.
Options available to you:
Store the image names in the self.mySprites dictionary, and load the images on demand. You should be aware that +[UIImage imageNamed:] implements internal RAM caching to speed things up, so this might also cause memory issues for you if the images are big, as the cache doesn't clear quickly. If this is an issue, consider using +[UIImage imageWithContentsOfFile:], although it requires some additional code (not much), which doesn't cache images in RAM.
Re-implement self.mySprites as an NSCache. NSCache will start throwing things out when the memory pressure gets too high, so you'll need to handle the case that the image is not there when you expect it to be, and load it from disk (perhaps using the above techniques)
CAKeyframeAnimation inherits from CAPropertyAnimation which in tern is inherited from CAAnimation.
If you see the delegate of CAAnimation class, it is strongly referenced as written below as it is declared -
/* The delegate of the animation. This object is retained for the
* lifetime of the animation object. Defaults to nil. See below for the
* supported delegate methods. */
#property(strong) id delegate;
Now you have added the reference of animation on imageView.layer, doing so the reference of imageView.layer will be strongly retained by CAAnimation reference.
Also you have set
animation.removedOnCompletion = NO;
which won't remove the animation from layer on completion
So if you are done with a image view then first removeAllAnimations from its layer and then release the image view.
I think as the CAAnimation strongly refers the imageView reference(it would also have increased it's retain count) and this could be the reason that you have removed the imageView from superview, after which it's retain count would still not be zero, and so leading to a leak.
Is there any specific requirement to set
animation.removedOnCompletion = NO;
since, setting
animation.removedOnCompletion = YES;
could solve the issue related to memory leak.
Alternatively, to resolve memory leak issue you can remove the corresponding animation on corresponding imageView' layer, by implementing delegate of CAAnimation, like as shown below -
/* Called when the animation either completes its active duration or
* is removed from the object it is attached to (i.e. the layer). 'flag'
* is true if the animation reached the end of its active duration
* without being removed. */
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag {
    if (flag) {
        NSLog(#"%#", #"The animation is finished. Do something here.");
    }
//Get the reference of the corresponding imageView
    [imageView.layer removeAnimationForKey:#"animation.trash"];
}
UIView *categoryView = [self.view viewWithTag:500];
NSArray *subviews = [categoryView subviews];
for (UIImageView *subview in subviews) {
if(![selectedCategories containsObject:subview.accessibilityHint]){
[subview.layer removeAnimationForKey:#"animation.trash"]; // either this
//or// [subview.layer removeAllAnimations]; //alternatively
[subview removeFromSuperview];
subview.image = Nil;
}
}

Using a String as Images Name

I am working on a while loop that spits out 30 images, each image having a different name. The way I approached this was by creating a NSString variable call img, which will be different with each iteration, i.e., "Badguy 1", "Badguy 2", ect... Then using that string as the name of the image being created.
TotalShips = 1
while(TotalShips < 31){
img = [NSString stringWithFormat:#"Badguy %i",TotalShips];
UIImageView *img = [[UIImageView alloc] initWithFrame: CGRectMake(10,20,20,20)];
img.image = [UIImage imageNamed:#"Badguy.png"];
[self.view addSubview: img];
TotalShips = TotalShips + 1;
}
This doesn't seem to work, and I haven't found very much help on changing an image's name.
Thanks,
Alex
The UIImageView has an property animatedImages (NSArray). Vou can easily play auround with animationDuration and animationReapCount. You can start the animation with [myImageView startAnimation] and stop with [myImageView stopAnimation].
Please read: https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIImageView_Class/Reference/Reference.html#//apple_ref/doc/uid/TP40006889-CH3-SW3
The file names can you build in a loop with 'NSString *fileName = [NSString stringWithFormat:#"image%i.png",imageName, iterator]'.
Not sure what you're trying to do, but I'll try to explain what your code does, maybe it helps you understand the problem:
TotalShips = 1
while(TotalShips < 31){
// here your img variable is a string, which will be 'Badguy 1', 'Badguy 2', etc
// you're not using this img value set here anywhere else in your code
img = [NSString stringWithFormat:#"Badguy %i",TotalShips];
// here you redeclare your img as an UIImageView
UIImageView *img = [[UIImageView alloc] initWithFrame: CGRectMake(10,20,20,20)];
// here you assign the image in the imageView to the image 'Badguy.png'
img.image = [UIImage imageNamed:#"Badguy.png"];
[self.view addSubview: img];
TotalShips = TotalShips + 1;
}
So, your code creates 30 different UIImageViews , all of them with the same image: 'Badguy.png', and adds them one on top of the other to the current view. I suppose this is not what you wanted to do.

UIImagePickerControllerEditedImage get nil

Hey guys I'm doing some image editing with UIImagePickerController. Here is some code in imagePickerController:didFinishPickingMediaWithInfo:
UIImage *editedImg = [info objectForKey:UIImagePickerControllerEditedImage];
UIImageView *imgView = [[UIImageView alloc] initWithImage:editedImg];
CGRect imgFrm = imgView.frame;
float rate = imgFrm.size.height / imgFrm.size.width;
imgFrm.size.width = size;
imgFrm.size.height = size * rate;
imgFrm.origin.x = 0;
imgFrm.origin.y = (size - imgFrm.size.height) / 2;
[imgView setFrame:imgFrm];
UIView *cropView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, size, size)];
[cropView setBackgroundColor:[UIColor blackColor]];
[cropView addSubview:imgView];
UIImage *croppedImg = [MyUtil createUIImageFromUIView:cropView];
The above is to set the image in a size*size view and draw a image from a view when the height of the image returned by picker is smaller than size.
Here is the code of createUIImageFromUIView:(UIView*)view :
+ (UIImage *)createUIImageFromUIView:(UIView *)view
{
UIGraphicsBeginImageContextWithOptions(view.frame.size, NO, 2.0);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[view.layer renderInContext:ctx];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return viewImage;
}
My problem is : when debugging, the 'editedImg'(defined in first line) just shows 'nil'. But, the following code works well. I get the corpView(shows 'nil' too) correctly and get cropped image and can encode it to base64 encoded string for sending to server side. I just want to know why the editedImg is nil(returned by [info objectForKey:UIImagePickerControllerEditedImage], but when I choose to print the info in debug mode, the output is not nil in the console)?
The editdImg gets nil, try:
UIImage *editedImg = [info objectForKey:#"UIImagePickerControllerOriginalImage"];
Get file size:
- (long long) fileSizeAtPath:(NSString*) filePath{
NSFileManager* manager = [NSFileManager defaultManager];
if ([manager fileExistsAtPath:filePath]){
return [[manager attributesOfItemAtPath:filePath error:nil] fileSize];
}
return 0;
}
Best wishes!
After some searching I accidentally found this : string value always shows nil in objective-c
This is the reason why I always see 'nil' in debug mode while the code works well.
You can get your cropped image size by
UIImage *croppedImg = [MyUtil createUIImageFromUIView:cropView];
NSData *dataForImage = UIImagePNGRepresentation(croppedImg);
Now you can check length
if (dataForImage.length)
{
}

Resources