Add StatusBarEffect and NavigationBarEffect classes to manage their color and style

[maxkoshevoi]

Port of this PR xamarin/Xamarin.Forms#8298

Important

Android implementation will need to be updated when XCT will move to Mono11+

Description of Change

• Added StatusBarEffect for StatusBar style manipulation.
• Added NavigationBarEffect for NavigationBar style manipulation (Android only).

Bugs Fixed

• Fixes [Enhancement] Add BarStyleManager to manage navigation and status bar color #708
• Fixes [Enhancement] Set StatusBar color for iOS and Android from any Page Xamarin.Forms#7314

API Changes

public class StatusBarEffect
{
    public Color Color { set; }
    public StatusBarStyle Style { set; }
}

public class NavigationBarEffect
{
    public Color Color { set; }
    public NavigationBarStyle Style { set; }
}

Behavioral Changes

Testing

• Android 10 and 11:
  

• UWP
  

• iOS
  

PR Checklist

• Has tests (if omitted, state reason in description)
• Has samples (if omitted, state reason in description)
• Rebased on top of main at time of PR
• Changes adhere to coding standard

• Updated documentation

[pictos]

@maxkoshevoi can you drop the NavigationBar implementation for this PR? Since it's just android we should work on the PlatformSpecific API. After this PR we can spec that, I already have something implemented (in a branch that I need to find) that we can use for that purpose.

[maxkoshevoi]

@pictos Sorry for long delay, was on vacation.

• Removed NavigationBar from the PR. Where should I include it then? Changing NavigationBar color on Android is is as valid as changing StatusBar color (what interesting is that NavigationBar style changes automatically according to color)
• Renamed effect to Window to reflect that it affects global window of the application (I was also thinking about Page, but this might mean that color will revert to default one once user leaves the page, which is currently not the case)
• Made some other minor changes and tested the effect on Android 10 and 11 (since they have different APIs for StatusBar style). Everything works

[pictos]

I have more change requests. Please avoid pushing changes in csproj and manifest/info.plist if they aren't needed.

[pictos]

@maxkoshevoi

@pictos Sorry for long delay, was on vacation.

Removed NavigationBar from the PR. Where should I include it then? Changing NavigationBar color on Android is is as valid as changing StatusBar color (what interesting is that NavigationBar style changes automatically according to color)
Renamed effect to Window to reflect that it affects global window of the application (I was also thinking about Page, but this might mean that color will revert to default one once user leaves the page, which is currently not the case)
Made some other minor changes and tested the effect on Android 10 and 11 (since they have different APIs for StatusBar style). Everything works

No need to be sorry, I really hope that you had a great vacation❣Thanks for pushing this forward

[maxkoshevoi]

@Cfun1 It's not in the platform specific namespace, so it can be used by just using xmlns:xct="http://xamarin.com/schemas/2020/toolkit".
XCT already has similar effects. For example SafeArea is iOS only.

[jfversluis]

Actually, we have a way to add platform specifics these days. So why don't we make the NavigationBarEffect into that?

On<Android>.SetNavigationBarColor() something like that. That makes clear that it's Android only, no confusion with users on iOS and UWP or other platforms and afaic we can then keep the NavigationBar name as it's closer to the Android terminology

[maxkoshevoi]

On<Android>.SetNavigationBarColor() something like that.

@jfversluis This was the way I implemented it initially, but there was an issue with accessing Android's activity, so we decided to convert it to an Effect.

Currently we get activity from a MainPage, so app will crash if we try to get it before MainPage is assigned. Issue is that this effect needs to be applied on MainPage's creation, so app crashes. Effect solves this problem, since it's applied to a page, and we can get activity directly from the page it's being applied to.

Alternative solution is to use obsolete Xamarin.Activity to get activity while MainPage is not set yet. When MAUI is released this solution can be migrated to use Essentials.CurrentActivity.

[Cfun1]

@maxkoshevoi there was recently a pr related to Android activity but not sure whether it also solves the issue you mentioned or no #1351

[maxkoshevoi]

@Cfun1 It doesn't. With current implementation, first time when ToolkitPlatform.Context can return any result is after Application.Current.MainPage is set. This effect needs to access it while MainPage is being created (so before it is set).

[Cfun1]

Gotcha I understand now.

[kerberosargos]

Hello I think there is a bug in iOS 12.4 and below. I have created report in here #1646