Improve handling of Obtainium's OWN launcher icons on Android

[deminearchiver]

Important
Do not confuse launcher icons - the icons of the Obtainium app itself - with app icons - the icons of apps added to Obtainium.

Describe the feature

My suggestion is to ditch flutter_launcher_icons altogether an instead create launcher icons manually, ensuring they align with Android Design Guidelines.

Also, the Obtainium icon just needs a makeover. Not a full redesign, but a slight touch to make it feel more integrated with other apps on the Android's home screen.

Describe alternatives you've considered

Currently, Obtainium uses the flutter_launcher_icons Dart-based tool to generate launcher icons for Android. This package is supposed to help cross-platform Flutter apps generate their icons, but it is severely limited by how the icons turn out. There are different design guidelines for launcher icons on different platforms, and a one-fits-all solution may exist, but it is not perfect. What's even better is that Obtainium is not cross-platform: it's an Android-only app, meaning that it only makes sense to stop depending on flutter_launcher_icons and manually handle the launcher icons Android resources.

Additional context

If we manage to agree on this issue, I'll try to draft a PR in which we can further discuss changes to launcher icons design and Android resources structure.

TL;DR

1. Establish a workflow for updating Obtainium's own launcher icons by removing the dependency on the flutter_launcher_icons Dart tool.

2. Improve the looks of Obtainium's launcher icons without affecting the design of the brand icon (change the background color, shape, sizing and positioning, etc.).

[ImranR98]

You seem really knowledgeable when it comes to mobile dev so I'm guessing this is a good idea, but what improvements do you have in mind? The current icon seems to look fine at least on my phone. My concern would be that changing the icon will end up being even more of a manual process (as it stands, I had to do some manual work for the notification bar icon iirc but flutter_launcher_icons handled the rest).

[deminearchiver]

My concern would be that changing the icon will end up being even more of a manual process.

I think it's better to make the process more manual as long as it becomes more platform-specific. I think that following the same process for adding icons as native Android-only apps do is the most sane decision at this point.

What improvements do you have in mind?

I'd like to change the alignment of the icon, and properly account for the safe area that Android recommends adaptive icons to follow. The full area is 108x108, but the safe area is 72x72 or 66x66 according to different sources.

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My plan is to create a follow-up issue which discusses improvements to Obtainium's splash screen. I have planned a lot to improve it: change the colors, add Kotlin code to properly handle it and change the activity theme overlay, etc.