[Bug] Xamarin.Forms 4 (4.0.0.425677) fails Image in Button when resources are defined in Android class library

[zijianhuang]

Description

To have multiple Android applications sharing the same resources mostly images, there's an Android class library containing the resources and assets, referenced by each Android app project. This has been working well with Xamarin.Forms 3.6 and previous versions. However, with Xamarin.Forms 4.0, images in buttons are not shown, while standalone images are shown.

Steps to Reproduce

Repository at https://github.com/zijianhuang/xamarinforms4bugs is demonstrating good ones and bad ones.

The master branch is with Xamarin.Forms 4 and Android app project that contains Resources. This is working well.

The ResourcesInLib is with Xamarin.Forms 4 and Android class project that contain Resources. Image of the button is not shown, while the standalone Image is OK

	<StackLayout>
		<Image Source="eye_24.png"/>
		<Label Text="Welcome to Xamarin.Forms!" 
		   HorizontalOptions="Center"
		   VerticalOptions="CenterAndExpand" />
		<Button ImageSource="eye_24.png" Text="Eye"/>
	</StackLayout>

Expected Behavior

Image of button is shown.

Actual Behavior

Image of button is not shown.

Debug Output:

[0:] FileImageSourceHandler: Could not find image or image file was invalid: File: eye_24.png05-28 21:39:04.011 W/ResourceType(25284): No package identifier when getting value for resource number 0x00000000

05-28 21:39:04.060 W/ResourceType(25284): No package identifier when getting value for resource number 0x00000000
[0:] FileImageSourceHandler: Could not find image or image file was invalid: File: eye_24.png

Basic Information

• Version with issue: Xamarin.Forms 4 (4.0.0.425677)

• Last known good version: Xamarin.Forms 3.6

• IDE: Visual Studio 2017 Pro

• Platform Target Frameworks:

  • Android: 5, 6, 7, 8, 9

Reproduction Link

https://github.com/zijianhuang/xamarinforms4bugs/tree/ResourcesInLib/

[zijianhuang]

I had just filed #6343 which might be related to this issue. After you Xamarin team fixing this, please ensure things work well with Xamarin.Forms.Visual.Material 4.

[PureWeen]

@zijianhuang one workaround for this is if you add literally any resource into your head project then it should all start loading for you

you can even just add some dummy image

resources\drawable\hack.png

after you do that then your images should start working.

[zijianhuang]

@PureWeen, No. And I had even better workaround: symbolic links, which I had used in much older Xamarin releases.. However, I would prefer proper solution supported by 3.6.

[PureWeen]

it should be part of the next 4.0 or 4.1 release

[samhouts]

closed by #6420