Use UIScreen over keyWindow to get size, so that size can be used without host application

[cltnschlosser]

Before without a host app the keyWindow would be nil, resulting in the screen size being reported as "0x0", now the size will be correct.

[CLAassistant]

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[cltnschlosser]

@alanzeino Can I get some feedback here? This is an improvement to using this framework for libraries which don't use host apps.

[reidmain]

I am sorry it has taken so long to respond @cltnschlosser. This PR looks solid and I don't any reason why we shouldn't merge it immediately.

I originally had some trepidation because I thought there would be some scenario where the main screen and key window wouldn't be the same size (perhaps some sort of iPad multiple screens testing or something). But the more I thought about it the more this current solution makes even less sense.

Why does adding the dimensions of the key window or main screen matter? It is because we're making the assumption that you'd do this if you wanted to snapshot a view controller's view and its dimensions should be the same as the window or screen? Shouldn't we just embed the dimensions of the view that is being snapshot then?

Regardless I tested your changes on projects that both have and don't have a host application and it worked great so 👍🏻.

[cltnschlosser]

@reidmain Thanks for the review :) Now just need someone to merge!

The dimensions matter because without them the file names aren't unique, for example when using the following devices, here are the suffixes. Without the screensize the names would conflict.

'platform=iOS Simulator,name=iPhone 7,OS=11.3' -> _iPhone_11_3_375x667@2x.png
'platform=iOS Simulator,name=iPhone SE,OS=11.3' -> _iPhone_11_3_320x568@2x.png

'platform=iOS Simulator,name=iPhone X,OS=12.2' -> _iPhone_12_2_375x812@3x.png
'platform=iOS Simulator,name=iPhone 8 Plus,OS=12.2' -> _iPhone_12_2_414x736@3x.png
'platform=iOS Simulator,name=iPhone Xs Max,OS=12.2' -> _iPhone_12_2_414x896@3x.png

Long term the size of the view might be a better solution, but this works out fine :)

[reidmain]

@reidmain Thanks for the review :) Now just need someone to merge!

The dimensions matter because without them the file names aren't unique, for example when using the following devices, here are the suffixes. Without the screensize the names would conflict.

'platform=iOS Simulator,name=iPhone 7,OS=11.3' -> _iPhone_11_3_375x667@2x.png
'platform=iOS Simulator,name=iPhone SE,OS=11.3' -> _iPhone_11_3_320x568@2x.png

'platform=iOS Simulator,name=iPhone X,OS=12.2' -> _iPhone_12_2_375x812@3x.png
'platform=iOS Simulator,name=iPhone 8 Plus,OS=12.2' -> _iPhone_12_2_414x736@3x.png
'platform=iOS Simulator,name=iPhone Xs Max,OS=12.2' -> _iPhone_12_2_414x896@3x.png

Long term the size of the view might be a better solution, but this works out fine :)

Ah of course. This is an option mask so if you don't include the name of the device you can't unique it. That was the assumption I was making.

Alright to not make any breaking changes I'll merge this right now and we can look into addressing the larger issue in the future. Thanks again @cltnschlosser.