There is the Images.xcassets file in my WatchKit App. As soon as I put any icon in that asset build failed with the error message: "The app icon set named "AppIcon" did not have any applicable content."
https://i.stack.imgur.com/6gcq4.png
This is an easy method to generate your WatchKit icons, which worked well for me:
Upload a source image to http://makeappicon.com
Go to Images.xcassets in the WatchKit app
Right click on the pane which includes AppIcon, select "Import...", and choose the watchkit folder that makeappicon.com generated for you
Most likely your watchKit app icons are not of the correct size. You need the following sizes
(these are all in pixels)
48 x 48
55 x 55
58 x 58
80 x 80
87 x 87
88 x 88
172 x 172
196 x 196
Basically all the numbers you see in at bottom under Images.xcassets you need to double them as they need to be retina display.
https://i.stack.imgur.com/XXBhC.jpg
Most likely your watchKit app icons are not of the correct size. You need follow the instructions in above image
In my case, I generated the images with required dimensions from Sketch. I then dragged and dropped the png files into the spots. No complaints from Xcode. My app doesn't use watch kit.
However build failed with the error message, "The app icon set named “AppIcon” did not have any applicable content". There were also warnings about the wrong dimensions of the image files. Not sure how Sketch did that but I went back and reconfigured export from Sketch, verified the exported dimensions, drag the new files back to the app icon spots in Xcode. This time build was successful.
Morality, if you see this error message, double check your image dimensions.
Lets write it down into lazy mode easy version, all other answers were confusing me the hell out. i hope following help others.
Step 1: AppIcon was empty
https://i.stack.imgur.com/T2WHi.png
Step 2: Want to add icon
so from AppIcon > on row1, col1 on 2x > i drag and dropped, the following invalid image:
https://i.stack.imgur.com/aEP80.png
Which had actual size as below:
https://i.stack.imgur.com/7ZpQB.png
Step 3: when i did build compile, it failed.
https://i.stack.imgur.com/iVW5y.png
Step 4: after searching
i found that for 2x the image size should be 40px by 40px so i modified that image into 40px by 40px from that invalid value.
https://i.stack.imgur.com/NqNQR.png
Step 5: Info.plist added entry as below.
https://i.stack.imgur.com/fOXdq.png
This time the build/compile worked and in my iPhone 7 i have the new icon.
Go to MakeAppIcon website, upload your image of AppIcon . It will automatically generate all resize images , give your mail id and get the zip file . And make sure when you upload in Assets.xcassets you used a OPT very clearly for image which size is 2x or 3x depending on your requirement .
I solved the problem!
originally I only selected Apple Watch checkbox in Xcode 6 and run very well. However, I got the same error in Xcode 7 without modifying anything. My solution is to select CarPlay checkbox in addition and put in two square icons with 120px and 180px for CarPlay. Now I can run my watchapp finally.
However, it cannot be accepted for submitting to Apple Store...
https://i.stack.imgur.com/UcNfW.png
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