iOS - UIImage imageNamed: returns null on device - ios

[UIImage imageNamed:filename]
This method returns null only on the device.
I know it's known problem and it's usually due to the fact that simulator is case insensitive.
I have tried solutions proposed here: UIImage imageNamed returns nil
But nothing worked out for me.
The case is simple: I have 4 files named:Bar#2x~ipad.png, Bar#2x~iphone.png, Bar~ipad.png, Bar~iphone.png.
All of them are in project with target checkbox checked.
NSLog(#"%#",[UIImage imageNamed:#"Bar"]);
That line of code gives me null for device and I really have no idea what I'm doing wrong right now.

I did have such a problem recently too.
After playing with filenames and paths sometimes it helps when you clean and rebuild your project.

I found myself in the same situation recently.
The solution in my case was adding the extension to the file name.
[UIImage imageNamed:#"Bar.png"]

Completely clean your build and redo it:
delete the app from the device
option-clean the whole build directory in Xcode (⌘-Shift-K)
quit xcode
delete ~/Library/Developer/Xcode/DerivedData
restart xcode, build and run

This just happened to me, and to discover was very tough: I had one image which where nil just on device
logoWhite.png
my code:
[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:#"LogoWhite"] forBarMetrics:UIBarMetricsDefault];
After a while of debugging, I noticed that the name of the image is beginning with capital case letter. Obviously this doesn't matter on OSX with a ignore case file system. iOs file system isn't, so the image worked on the simulator but not on the device.
I bet that all the solutions about cleaning derived data and rebuild did randomly end with renaming the image, and this would do the trick as well. Just posting here for future reference :)

I encountered this issue and just fixed it. I listed the solution below as a reference.
I have several images, and use [UIImage imageNamed:filePath] to show them. All of images displayed well except 1 on simulator/device, but all of them can be seen on OS X. For that image, [UIImage imageNamed] always return null.
After few minutes' investigation, I found that the image cause problem is far big in file size: 4.1M. Others are all around 800kb. They have nearly same size in dimension.
Then I try to open it in image editor, then re-save it. After this, the size dropped to 800k. problem solved.
The reasons I guess,
[UIImage imageNamed:filePath] has a max file size limit? (low possibility, but need to check official document)
the image itself has some error. But OS X has better tolerance than iOS. so iOS cannot read and return null. This issue is like OS X can play more types of video files than iOS since it support more codecs.
so if you encounter this issue in the future, take a few seconds look at the file size. Hope help.

This is an odd problem, which I hadn't seen until this week.
Below are my findings, and a workaround to your problem.
In my iPhone app, I download an image and store it locally, and this had always worked fine.
But now when I run the same code, it was suddenly failing to create a UIImage out of it using the imageNamed function, and now it was returning nil.
Three notes though:
This exact code did work before, using the same source code and .png image files. I'm not sure if my copy of XCode 6.x or iOS 8.x quietly updated itself in the meantime.
The code continues to work okay (with the same image file) on the iPhone simulator. It just doesn't work on a real device.
Take a look at the code below. When UIImage:imageNamed failed, I ran some code to check if the file actually existed.. and it did. Then I loaded the binary data from the file using NSData:contentsAtPath (which also proves that the file exists and was in the right folder), then created a UIImage out of that, and it worked fine.
Huh ?!
UIImage* img = [UIImage imageNamed:backgroundImageFilename];
if (img != nil)
{
// The image loaded fine (this always worked before). Job done.
// We'll set our UIImageView "imgBackgroundView" to contain this image.
self.imgBackgroundView.image = img;
}
else
{
// We were unable to load the image file for some reason.
// Let's investigate why.
// First, I checked whether the image was actually on the device, and this returned TRUE...
BOOL fileExists = [[NSFileManager defaultManager] fileExistsAtPath:backgroundImageFilename];
if (fileExists)
NSLog(#"Image file does exist.");
else
NSLog(#"Image file does not exist.");
// Next, I attempted to just load the bytes in the file, and amazingly, this also worked fine...
NSData *data = [[NSFileManager defaultManager] contentsAtPath:backgroundImageFilename];
if (data != nil)
{
// ..and then I COULD actually create a UIImage out of it.
img = [UIImage imageWithData:data];
if (img != nil)
{
// We have managed to load the .png file, and can now
// set our UIImageView "imgBackgroundView" to contain this image.
self.imgBackgroundView.image = img;
}
}
}
As I said, this code does provide a workaround for this problem, but it's very odd that it's suddenly started happening.
And, I should say, I did try the other suggestions in this thread, cleaning the project, removing the DerivedData, completely removing the app from the device, and so on, but they didn't make any difference.
I would be interested in knowing if anyone else hits this issue, and finds that my code sample works for them.
Update
I'm an idiot.
I'm not sure if the UIImage:imageNamed function has changed or something (and if so, why it continues to work okay on the iPhone 8.1 Simulator), but I found the following one line does work okay:
UIImage* img = [[UIImage alloc] initWithContentsOfFile:backgroundImageFilename];
So it seems as though you should use this function for loading images which aren't a part of your app's bundle.

I also have same issue then : XCode - Build Phases - Copy Bundle Resources -{see image is available or not}- add{image} - clean - delete app - Run .

I would like to add one more important point to all the above solutions
Make sure you add your image resource to right target
By mistake if Developer mess-up link with resource and target then conditions arise.
if you have multiple target then double check the resource are set to correct target.
Attached screenshot example in case of resource link between multiple targets.

Related

Xamarin Forms CircleImage with source from file

I'm using a plugin CircleImage from https://github.com/jamesmontemagno/Xamarin.Plugins/tree/master/ImageCircle
I'm using it in a listview. I noticed it's working fine with image from a url but I can't find a way to show an image from embedded resources or files. Could you explain me how do that?
Thank you in advance!
Is the image in your Resources folder on iOS and Android platforms and in the root on Windows Phone?
You probably want to use the following to set the source of a local image:
Source = ImageSource.FromFile("someimage.png")
Or you might even try:
Source = (FileImageSource)ImageSource.FromFile("someimage.png")
Also be careful with upper and lower case file names. I suggest making everything lower case. The iOS simulator will not care about casing (since Macs do not care), but a real iOS device will care.
For other developers I write and describe my solution for that. I have a MVVM model. In this model there is property
ImageSource image
when I fill the data in the model (r in the example) I verify if taking an embedded image or an image from file system
if (images.Count == 0) {
// from file
r.Image = ImageSource.FromFile ("GenericImageFromResource.png");
} else {
// get the file image from file system
//(required an implementation for each platform)
r.Image = ImageFinder.GetImage (images.First().FileName);
}

loading user images works in simulator but not on the iphone xcode 6 Swift

Im trying to load(and upload) images in my app(by picture path).
This is working in my simulator. everything works there. only when im trying to do this on the iphone itself it won't work and i see just the empty UIImageviews.
The paths are loaded the same as in the simulator. And originate from:
PHImageManager.defaultManager().requestImageDataForAsset(asset, options: nil)
{
imageData,dataUTI,orientation,info in
cell.setString(info["PHImageFileSandboxExtensionTokenKey"] as String,name:dataUTI as String)
}
And the PHImageFileSandboxExtentionTokenKey is split into the data and the url when loading the image.
this results in the simulator as :
/Users/Twizzler/Library/Developer/CoreSimulator/Devices/3E671415-8B83-44DA-870F-19BF2BC11F8F/data/Containers/Data/Application/8872109F-3784-40EB-BEB6-4E9FDABE013D/Documents/1613945_10200645161051698_4122753901212984922_n.jpg
and in the iphone as:
/private/var/mobile/Media/DCIM/102APPLE/IMG_2607.JPG
Im loading the image like this:
let image = UIImage(named: "/private/var/mobile/Media/DCIM/102APPLE/IMG_2607.JPG")
cell.imageView.image = image
in this case i put the image url hardcoded (this is in the final app an array of images)
I don't get an error or stack trace. When placeing a breakpoint im seeing the image information in the same way as the simulator
as suggested by the answer im now trying to load them as follows:
let image = UIImage(contentsOfFile: "/private/var/mobile/Media/DCIM/102APPLE/IMG_2607.JPG")
cell.imageView.image = image
This isn't working and i can't upload the files
That’s not how imageNamed works—as the documentation states, that looks for an image with the given name inside your app’s bundle. Try imageWithContentsOfFile.
Well i fixed it! after some puzzling days im now using this way to access upload and
cell.imageView.image = UIImage(data: array[indexPath.row][0] as NSData)
This shows the image. I can save the NSData in the CoreData and reload the image on this way.
To lighten the load on the system im using this:
cellData.checked = 1
var imageData = UIImageJPEGRepresentation(cell.imageView.image, 1)
self.array.append([imageData,cellData.imageData] )
let myObj : ViewControllerImagePicker = self.parentViewController as ViewControllerImagePicker
let textfield: UILabel = myObj.amountLabel! as UILabel
textfield.text = String(self.array.count )
cell.textLabel.alpha = 1
this code is being called when there is clicked on a cell. by setting the cellData.imageData i can recall the cells (when clicking back to the collection view)
I do not know if the way im doing it is correct or works with more that 10 files because of data usage problems. But in my case with a max of 6 selected pictures it works like a charm
The simulator works completely different than a real device when it comes to files, the app bundle and sandboxing.
For starters the simulator will let you write to and add or change files in your app bundle. iOS running on a real device won't let you do this.
You can't hardcode any paths in your app. Even if it works today or on your device in test mode that doesn't mean it will work on a released version. And even if it does it could stop working on any update. Apple several times has changed where things are stored and the path structure in the phone. And where you are allowed to write.
Make bundle calls to get the path locations of standard folders.
Use the assets library to load images from the photo library, or to save them there.
There are tons of resources and tutorials online on how to do this.

Xcode 6.0.1 - some linked folder images not working

I am getting images that previously worked coming back as nil in the latest version of Xcode, nothing has changed but the image objects are coming back as null. I've tried cleaning and deleting the app, and even copied the entire folder to see if that was the issue, the folder shows up in the build phases "copy bundle resources". The folder and file names are correct, this project has been compiled and launched half a dozen times. The #2x file is also in the folder.
UIImage *iSearch = [UIImage imageNamed:#"/assets/images/controls/search_bg.png"];
UIImage *iSearchB = [UIImage imageNamed:#"/assets/images/controlsb/search_bg.png"];
NSLog(#"iSearch: %#, iSearchB: %#", iSearch, iSearchB);
Log:
2014-09-23 14:29:45.651 SmartChoice[16178:469424] iSearch: (null), iSearchB: (null)
I also have another issue where this is failing on
AppDelegate.h
return UIApplicationMain(argc, argv, nil, NSStringFromClass([IWAppDelegate class]));
Instead of the actual code on the view controller in the call stack.
//update, solved the second issue using info here, unsure why they turned that off by default: http://ijoshsmith.com/2011/11/28/debugging-exceptions-in-xcode-4-2/
You should not be using imageNamed: with a fake name with slashes to dive into a folder hierarchy. That's fragile and unsupported, and the fact that it ever worked is just chance. Don't gamble. Either use an asset catalog (far and away the best approach nowadays) or use one of the NSBundle methods that lets you specify the subdirectory, such as pathForResource:ofType:inDirectory:.
I have solved this, apparently the preceding slash, which was required before, does not work. I have changed it to [UIImage imageNamed:#"assets/images/controls/search_bg.png"]; and it works.

How to get UIImage of AppIcon?

I am using Assets Catalog, and adding app icon of various size to the assets is okay.
But when I tried to get the UIImage programmatically, it returned nil.
UIImage *appIcon = [UIImage imageNamed"AppIcon"];
The app icon is named AppIcon (the default), and the actual files are app-icon-256.png etc.
I also noticed that unlike normal images, app icons are in an "App Icon" set, in the directory AppIcon.appiconset. Normal images are in the directory someimage.imageset.
The problem is that the AppIcon from the asset catalog is not placed in the the catalog after compiling. Instated it it copied into your apps bundle, just like before.
The name conversion used when copying the icon to the app bundle is AppIcon<size>.png, where the size is for example 40x40 or 72x72
You can get your apps icons by specifying the size of the app icon you want:
UIImage *appIcon = [UIImage imageNamed:#"AppIcon40x40"];
The >iOS10 answer is:
Copy & paste this extension.
extension Bundle {
var icon: UIImage? {
if let icons = infoDictionary?["CFBundleIcons"] as? [String: Any],
let primary = icons["CFBundlePrimaryIcon"] as? [String: Any],
let files = primary["CFBundleIconFiles"] as? [String],
let icon = files.last
{
return UIImage(named: icon)
}
return nil
}
}
Then just call this:
Bundle.main.icon
SwiftUI:
Image(uiImage: Bundle.main.icon ?? UIImage())
Update Sep 12 2022: This doesn't work anymore, as of iOS 16.0.0 at least.
The methods of loading the main app icon highlighted in other answers like from Rufat Mirza used to work, and still does for debug builds, but I got an app rejection from Apple saying the app was crashing on launch. Turns out that the builds that contained this code started crashing on iOS 16, but only when installed via App Store/TestFlight (builds using the "Release" Configuration). What's more weird is that builds using the "Release" Configuration compiled via Xcode also wouldn't crash, only when uploaded to App Store and downloaded from TestFlight, so keep this in mind.
The fix was, unfortunately, to create a new Image asset with the same content as the AppIcon asset.
Note that this workaround still works for macOS as of the 12.5.1 and whatever macOS version Apple is using when reviewing their apps as of today, but since I already had to duplicate the asset for iOS, I also used the same asset for macOS to avoid this little hack :)
For those of us, who still need an obj-c version, I made a transcript of the relevant parts of the answer by Rufat Mirza:
NSDictionary *icons = [[NSBundle mainBundle] infoDictionary][#"CFBundleIcons"];
NSDictionary *primary = icons[#"CFBundlePrimaryIcon"];
NSArray *files = primary[#"CFBundleIconFiles"];
return [UIImage imageNamed: files.lastObject];

(IOS) Cordova Camera Plugin Referring to deleted images

I'm building a cordova app (primarily for IOS & Android) in which the user can take an image, retake (, etc.) it and save it locally.
I'm currently struggling with the cordova cameraPlugin. So, here a short description of the problem.
When the user takes an image, it's saved locally in the apps temp folder and the user is able to view in in the UIWebView. On retaking, the image will be deleted from the temp folder and should not be available any longer (in RAM and local FS).
It works as long as the user doesn't retakes the image 2 or more times, if he does instead of the last image the first image will be referenced/rendered in WebView. After reopening the app, the image is displayed correctly.
An Example:
The user takes the first image. ==> cdv_photo_001.png
The second. ==> cdv_photo_002.png and the first one will be deleted (which seems to work correctly)
And the third. ==> cdv_photo_001.png and the second image will be deleted.
The third image will look the same as the deleted first one. This happens with every image after the third one.
It works fine after restarting the app
I've already tried to disable the App-Cache, delete the app cache before updating the image, refreshing the page and looking for answers online.
I'm getting an error when opening the camera UI, but I could not find a solution for it either.
Snapshotting a view that has not been rendered results in an empty snapshot. Ensure your view has been rendered at least once before
snapshotting or snapshot after screen updates.
The code for the camera Call:
function getPhoto() {
navigator.camera.getPicture(getPhotoOnSuccess, getPhotoOnFail, {
quality: 25,
destinationType: Camera.DestinationType.FILE_URL,
correctOrientation: true,
encodingType: Camera.EncodingType.PNG
});
}
In getPhotoOnSuccess I'm basically saving the image path to a db and appending it with jQuery to the view.
And the code to delete the image: (sidenote I`m new to Objective C)
- (void) deleteImageByPath:(NSString *)imagePath withSelector:(SEL)selector{
NSError *error = nil;
NSFileManager *mgr = [NSFileManager defaultManager];
NSString *tempFolder = NSTemporaryDirectory();
if([mgr removeItemAtPath: imagePath error:&error] == NO) {
NSLog(#"File deleted");
}
//The files can be edited as well, so there can be two files in different directories
if(error != nil){
NSString *imgEl = tempFolder;
imgEl = [imgEl stringByAppendingPathComponent:imagePath.lastPathComponent];
if(![mgr removeItemAtPath:imgEl error:&error]){
NSLog(#"Old element couln't be deleted.");
}
}
[self performSelector:selector withObject:error];
}
The file is not in the directory anymore after deleting it, so I guess it works.
An important detail could be, that I wrote my own IOS cordova plugin, because the method for the file system access provided by cordova sucks.
So thats it.
The specific question is: Why and how is this happening and is there a chance to change this behavior? If yes, how should I proceed?
By the way, I`m using cordova 3.1.0 and the build target is IOS 7.
Thanks in advance.
Ok folks, I finally got it.
The whole problem was not related to my code or any of the cordova code.
So why did it happen? ==> I don't exactly know that, for it seems that this bug or whatever you might call it, has occurred to many people.
And they all tried to delete or deactivate the cache as I did, some of their problems are very close to my own but most aren't, so it took a while til I found a solution.
I read this thread and tried to append a timestamp to the image path and it worked!
My conclusion to this it, that there might be a problem with the UIWebView and the cache management.
Or it might proof as a general WebView problem, I will be able to check that in a few days on an Adroid device.

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