Android 11.0 native SystemUI pull-down notification bar UI background set to customization of rounded background (2)

1 Introduction

 In the 11.0 system rom customization development, the background of the drop-down notification bar in the drop-down status bar of the native system SystemUI defaults to a white four-corner background. Because in product design, the background of the drop-down notification
bar notification needs to be changed from the default four-corner background to It has a rounded background, so it is necessary to analyze the default background of each notification in the system's native drop-down notification bar,
and then through the notification bar process of systemui, set the background of each notification in the notification bar part of the default drop-down status bar UI to change to a rounded background

2. The UI background of the native SystemUI drop-down notification bar is set to a custom (2) core class with a rounded corner background

frameworks\base\packages\SystemUI\src\com\android\systemui\statusbar\notification\row\ActivatableNotificationView.java
frameworks\base\packages\SystemUI\src\com\android\systemui\statusbar\notification\row\ExpandableOutlineView.java
frameworks\base\packages\SystemUI\src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayout.java

3. The UI background of the native SystemUI drop-down notification bar is set to a rounded background (2) Core function analysis and implementation
 3.1 Core code analysis and implementation of NotificationStackScrollLayout.java

      @ShadeViewRefactor(RefactorComponent.COORDINATOR)