Lock screen notification layout of Android 12.0 native system SystemUI drop-down status bar and notification bar view

1 Introduction

 In the 12.0 system rom customization development, the function of the lock screen interface of the system's native systemui is also very important, so in the lock screen page layout, there is also a notification bar layout, so the next step is for the notification bar of the off screen and bright
screen Analyze the relevant process of the layout, and see what functions the lock screen page does after the screen is turned on

2. The core class of the lock screen notification layout of the native system SystemUI pull-down status bar and notification bar view

frameworks/base/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardViewMediator.java
frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java
frameworks/base/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java

3. Core function analysis and implementation of the lock screen notification layout of the native system SystemUI drop-down status bar and notification bar view
3.1 Analysis of bright screen related methods in PhoneWindowManager.java

Among the related lock screen functions of the system systemui, the lock screen notification bar is also an important module. The lock screen notification is a plug-in that indicates that the system or software notification information can be displayed by adding a desktop under the Android lock screen. Such as mailboxes, or custom software notifications, so when customizing the notification bar, you can use these process analysis to know how the lock screen notification is displayed, and then you can implement the custom lock screen notification

 // Called on the DisplayManager's DisplayPowerController thread.
      @Override
      public void screenTurningOn(int