I'm implementing the dark mode for iOS. The problem occurs with the images:
I've opened the Assets.xcassets and changed the "appearances" "to Any, Dark"
Of course I've added the new image.
Unfortunately the images are not being redrawn when overriding the environment interface style in xcode.
I've tried catching the traitCollectionDidChange method in my viewController and it is properly called. I could set the new image (origImage_dark), but shouldn't it be automatic? That's what the asset settings are made for. I'm using the .alwaysOriginal rendering of the image.
Running the app with dynamic resolve of the image helped:
let image = UIImage(named: "someImage")
let asset = image?.imageAsset
let resolvedImage = asset?.image(with: traitCollection)
After this, reverting back to the original way of setting the images seemed to work. Xcode, thanks a lot!
I'm new to iOS app development and I begun to learn from this great tutorial:
Start Developing iOS Apps (Swift)
https://developer.apple.com/library/content/referencelibrary/GettingStarted/DevelopiOSAppsSwift/WorkWithViewControllers.html#//apple_ref/doc/uid/TP40015214-CH6-SW1
Everything looks great but when trying to load an image from "Camera roll" on the simulator, I get the image shown oversized and filling all the iPhone simulator screen instead of just showing into the UIImageView box as shown on tutorial images.
The funny fact is that also downloading the correct project provided at the end of the lesson (see the bottom of the page) I get the same issue.
Googling around I get some ideas to insert a:
// The info dictionary may contain multiple representations of the image. You want to use the original
guard let selectedImage = info[UIImagePickerControllerOriginalImage] as? UIImage else {
fatalError("Expected a dictionary containing an image, but was provided the following: \(info)")
}
// Set photoImageView to display the selected image
photoImageView.image = selectedImage
photoImageView.contentMode = UIViewContentMode.scaleAspectFit
// Dismiss the picker
dismiss(animated: true, completion: nil)
after loading image from the camera roll, but lead to no results...
I'm using Xcode 9.2 with deployment target 11.2 and iPhone 8 plus as a target for the simulator.
Any help is apreciated.
It happens because the sample code is only restricting the proportion of the UIImageView (the 1:1 constraint you added in storyboard). In this way, it will always keep your imageView squared but will not limit the size.
As the sample tells, you entered a placeholder size, that is only kept until you set some image on it. When you enter a new image on the UIImageView it changes to the size of the image you set (in your case, probably a bigger image for the camera roll). That's probably why its getting so large.
I think the easy way to fix this to add other constraints in storyboard to limit the size (like actually size or border constraints).
I'm attempting to use PDF files as icons in an app I'm working on. The issue I'm encountering is I'm getting inconsistent tint colors.
If I set a button image from interface builder, the icon image shows up black at runtime. Every time. Regardless of what I attempt to set from interface builder.
I tried setting my button icon image via code and instead of showing up black, it's white:
let myGraphicFile = UIImage(named: "myPDFImage")
let myButtonImage = myGraphicFile?.imageWithRenderingMode(UIImageRenderingMode.AlwaysTemplate)
myButton.setImage(myButtonImage, forState: .Normal)
From code, regardless of what I attempt to set the tint to, it's always white from code.
I discovered this post relating to Xcode 6.x, but I think it might be dated, as I'm able to partially do it, but I can't set the tint.
Use PDF in XCode for an AppIcon (.appiconset collection)
I create the icons in Inkscape, save as PDF 1.5. I add the file to Images.xcassets. In Images.xcassets' attributes inspector, I'm setting:
Devices to Universal
Scale factor to Single Vector.
Summary: I can get it to show up and scale properly, but it's either black from interface builder or white from code. I suspect I'm missing something re: how to save the file from Inkscape.
Thank you for reading. If you have any suggestions, I welcome them.
I have figured out how to create vector icons with Inkscape. When you use PDFs to display icons in iOS, you need to alter the Attributes Inspector for your icon in xcAssets as follows:
1) Drag the PDF into xcAssets
2) Set devices (I did Universal and it worked fine)
3) If your PDF icon is under 1x, 2x, or 3x size class, drag it to Universal and delete the rest of them.
4) Set Scale Factors to Single Vector.
5) Render as Template Image.
Once it's configured there, then you just treat it was you would any other image in interface builder. It's essentially the same thing I was doing in code, but I don't think it gets done in code...it's gotta be done on xcAssets where the image lives. It's my understanding iOS renders vector images for the size class at run time. I think by attempting to tweak it in code wasn't working because the image had already been rendered.
If anyone has any questions on this, I found this link helpful in resolving my issue.
Additionally, this post covers the topic, too. https://stackoverflow.com/a/25804358/4475605
Since iOS8, the behaviour of Mail with the pasteboard seems to have changed.
I am trying to copy both images and text from my app, in a format that I can paste into the Mail app.
A UIPasteboard containing both images and text will only paste the images into Mail. A pasteboard containing one or the other works fine.
I create a dictionary for each text and image element, add them all to an array, then set pasteboard.items to the array. This method has worked for a year or two.
My guess would be that Mail now takes the "best" data in the pasteboard, and assumes that the text was included only as a fallback (such as a text description).
Has anyone else observed the same problem, and is there a workaround?
When I tried to add some text and a image to the UIPasteboard a few days ago, I found that ONLY the image was added to the UIPasteboard.
UIPasteboard.generalPasteboard().string = text
UIPasteboard.generalPasteboard().image = image
I use the code above then check UIPasteboard.generalPasteboard().string was nil, I firmly sure that my text wasn't nil. So, this may be a bug.
I am pretty new to iOS and Xcode.
I tried to load an image with
[UIImage imageNamed:#"imageName.png/jpg and so on"];
but it only returns nil. The image should be in my project bundle, considering the fact that I can choose it from drag and drop menus in the InterfaceBuilder and it was added to Xcode via the "Add files to "projectname"..." menu.
It makes no difference whether I use .png or .jpg images, the result stays the same: they work via IB but not if I try to run the imageNamed method myself.
There are only a few reasons why an image would come back nil with imageNamed:
The image is not in your bundle. Make sure the image is actually in your project. Make sure the target is checked by clicking on the file and selecting the target it belongs to.
You have the image name spelled incorrectly or a problem with the extension.
You are using a retina display but do not have an #2x image. Try changing your simulator to retina and see if it shows up.
If you are using an asset catalog make sure you have the correct devices selected in the attribute inspector.
Some tips:
If you are testing using simulator delete the app off of your simulator and clean your project, then re-run. If it still shows up it should show up on your phone (if it doesn't it's probably an issue with the case of the filename or the #2x version).
If you are testing on your phone and it doesn't show up, make sure you are using the same version of the simulator (if you have an iPhone 4/4s make sure to use the 4/4s simulator with retina).
One last thing according to this post: JPG image doesn't load with UIImage imageNamed There is some issue with certain JPG types working with imageNamed and no extension. IMO, you should be using PNGs anyway since iOS compresses them for you, unless you just have to use JPG.
Re Mike Weller's comment. The checkbox is ....
If you verified all of the above and are finding that your UIImage(named: "myImage") returns nil from code inside of a dynamic framework you are building, then you have to change the code to:
UIImage(named: "myImage", in: Bundle(identifier: "com.myframework.name"), compatibleWith: nil)
This should retrieve the asset from CXAssets correctly.
In my case, the PNG was malformed.
For some reason Xcode preview shown it correctly, but when I tried loading it with UIImage, it returned nil.
I just had this issue for jpg files named on disk "file.jpg"
I was trying to load without the extension, just #"file". While this works fine for pngs, it does not for jpg. Once I used #"file.jpg", it worked!
Swift 5
If you get UIImage nil in dynamic framework, you should set image with bundle identifier.
You can create an extension to Bundle like this;
Create an extension;
extension Bundle {
public static let myFramework = Bundle(identifier: "com.myFramework.bundle")
}
Then you can use like this;
UIImage(named: "myImageName", in: Bundle.myFramework, compatibleWith: nil)
Or
You can use like this;
UIImage(named: "myImageName", in: Bundle(for: type(of: self)), compatibleWith: nil)
I think the first one is more useful because it's more readable than second one.
Try re-exporting your image.
I had a similar problem, UIImage imageNamed was returning nil and none of these answers fixed my problem.
I found out that it was actually something wrong with the png file. I opened the file in GIMP image editor, saved it as a new file, exported it again as png and magically it started working.
I didn't change anything in code at all so there was definitely something wrong with the actual image file.
try
[UIImage imageNamed:#"imageName.png"];
instead (with an extension)
I had the same problem: #"photo.jpg" resulted in 'nil' UIImage.
Changing to the "actual" filespec, #"photo.JPG" works fine!
I hadn't realized there was case-sensitivity there! VERY non-intuitive.
i had a similar issue, finally the cleanup fixed it: the image showed up in the simulator, but id did not show up when running the app on the iPhone.
What I did:
1) deleted the app from the iPhone
2) performed Product/Clean
after that the bug was fixed and the image showed up!
Try to use UIImage(contentsOfFile:) instead of imageNamed. It worked for me with downloaded images.
Check that file has no space at the end.
The name like name #2x.png will fail loading, but name#2x.png is fine
Does the image work on the simulator but not on the device?
If so, in this scenario it is always to do with the case of the name. The device requires exact case and the simulator is not so fussy if I remember correctly.
e.g. for an image named image.png
[UIImage imageNamed:#"Image"];
would work on the simulator but not on the device...
Make sure you have the image for the DEVICE you are using in your .xcassets file. An image flagged for iPad won't show up on the phone (or the simulated phone).
In addition to #Inturbidus's answer:
For those who came here working on Application Extensions:
The image you are working with should belongs to both targets - hosted app and extension.
In other case you'll always getting nil trying to access it from within the extension's code.
For Xcode 6.4, click on Images.xcassets and check whether there are entries for each image that you called. You may right-click on the image and select "Show in Finder" to check if the images are the correct ones added.
Make sure the Attributes Inspector name field of the image matches exactly the name you're using. In my case the image was part of a folder and so the image name was "folder/name". Using this long name solved the problem. XCode 7.3.1
In my case, using a name with accented characters proved to be a poor idea. I changed Astéroïdes to Asteroids and it worked fine.
In my case problem was with image name in asset catalog.
For example if you have image with name "TEst" and change name to "Test", changes won't be indexed. If your teammate will pull commit with this changes, image in his asset catalog will have previous name "TEst".
Very small chance to catch this situation but it's possible.
I had multiple .xcassets in my projects and 2 had duplicate name of images. So it was not loading the image in my case.