rk3568开启双屏异显异触摸时键盘焦点及分发事件固定在主屏

OS：Android11

需求描述：当app启用双屏异显双触摸，物理键盘只能固定在主屏有作用。

问题现象：双屏异显异触，带物理键盘输入。打开异显app，物理键盘的按键事件分发到主屏。 当触摸副屏的时候，物理键盘事件分发到副屏。当现再次触摸主屏，物理键盘的键事件分发到主屏。

问题分析：在之前3288 Android7上，没有该问题的。经了解是Android只支持一个屏的焦点事件，即默认是在主屏这边。Android10以后，支持多屏显示焦点事件，比如多个屏单独使用输入法等，这就导致触摸哪个屏，焦点事件就随着哪个屏走。

该需求最终实现是RK原厂提供的path：

涉及修改文件：frameworks/base
core/java/android/view/IWindowManager.aidl
core/res/res/values/config.xml
services/core/java/com/android/server/policy/PhoneWindowManager.java
services/core/java/com/android/server/wm/RootWindowContainer.java
services/core/java/com/android/server/wm/WindowManagerService.java

diff --git a/core/java/android/view/IWindowManager.aidl b/core/java/android/view/IWindowManager.aidl
index 5a32d283b17d..da90b9ca35e6 100644
--- a/core/java/android/view/IWindowManager.aidl
+++ b/core/java/android/view/IWindowManager.aidl
@@ -766,4 +766,10 @@ interface IWindowManager
      */
     void requestScrollCapture(int displayId, IBinder behindClient, int taskId,
             IScrollCaptureController controller);
+
+    /**
+     * Switch focus at defautl/external display.
+     * @hide
+     */
+    void switchFocusedScreen();
 }
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 2ebd8bb36a03..f8ccec591465 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -2025,7 +2025,7 @@
 
     <!-- Whether the system enables per-display focus. If the system has the input method for each
          display, this value should be true. -->
-    <bool name="config_perDisplayFocusEnabled">false</bool>
+    <bool name="config_perDisplayFocusEnabled">true</bool>
 
     <!-- Whether a software navigation bar should be shown. NOTE: in the future this may be
          autodetected from the Configuration. -->
diff --git a/services/core/java/com/android/server/policy/PhoneWindowManager.java b/services/core/java/com/android/server/policy/PhoneWindowManager.java
index 5003fca4bada..a5a1d5bc702b 100755
--- a/services/core/java/com/android/server/policy/PhoneWindowManager.java
+++ b/services/core/java/com/android/server/policy/PhoneWindowManager.java
@@ -2859,6 +2859,13 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                 mScreenshotRunnable.setScreenshotSource(SCREENSHOT_KEY_OTHER);
                 mHandler.post(mScreenshotRunnable);
             }
+            if(down){
+                try{
+                    mWindowManager.switchFocusedScreen();
+                } catch(RemoteException e){
+                    e.printStackTrace();
+                }
+            }
             return -1;
         } else if (keyCode == KeyEvent.KEYCODE_BRIGHTNESS_UP
                 || keyCode == KeyEvent.KEYCODE_BRIGHTNESS_DOWN) {
diff --git a/services/core/java/com/android/server/wm/RootWindowContainer.java b/services/core/java/com/andr
oid/server/wm/RootWindowContainer.java
index 197e2188c346..d41cd367b1b5 100644
--- a/services/core/java/com/android/server/wm/RootWindowContainer.java
+++ b/services/core/java/com/android/server/wm/RootWindowContainer.java
@@ -457,6 +457,12 @@ class RootWindowContainer extends WindowContainer<DisplayContent>
         int topFocusedDisplayId = INVALID_DISPLAY;
         for (int i = mChildren.size() - 1; i >= 0; --i) {
             final DisplayContent dc = mChildren.get(i);
+            if(mWindowManager.mFocusedInSecondDisplay&&dc.isDefaultDisplay){
+                continue;
+            }
+            if(!mWindowManager.mFocusedInSecondDisplay&&!dc.isDefaultDisplay){
+                continue;
+            }
             changed |= dc.updateFocusedWindowLocked(mode, updateInputWindows, topFocusedDisplayId);
             final WindowState newFocus = dc.mCurrentFocus;
             if (newFocus != null) {
@@ -467,7 +473,7 @@ class RootWindowContainer extends WindowContainer<DisplayContent>
                 if (topFocusedDisplayId == INVALID_DISPLAY) {
                     topFocusedDisplayId = dc.getDisplayId();
                 }
-            } else if (topFocusedDisplayId == INVALID_DISPLAY && dc.mFocusedApp != null) {
+            } else if ((topFocusedDisplayId == INVALID_DISPLAY) && dc.mFocusedApp != null) {
                 // The top-most display that has a focused app should still be the top focused
                 // display even when the app window is not ready yet (process not attached or
                 // window not added yet).
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/and
roid/server/wm/WindowManagerService.java
index 1ae8e783e21b..deb2a2cfe9db 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -754,6 +754,8 @@ public class WindowManagerService extends IWindowManager.Stub
     SettingsObserver mSettingsObserver;
     final EmbeddedWindowController mEmbeddedWindowController;
 
+    boolean mFocusedInSecondDisplay = false;
+
     @VisibleForTesting
     final class SettingsObserver extends ContentObserver {
         private final Uri mDisplayInversionEnabledUri =
@@ -8337,4 +8339,26 @@ public class WindowManagerService extends IWindowManager.Stub
             Binder.restoreCallingIdentity(origId);
         }
     }
+
+    /**
+     * Switch focus at default/second screen.
+     */
+    public void switchFocusedScreen(){
+            if (mFocusedInSecondDisplay){
+                setFocusedInSecondDisplay(false);
+            }
+            else{
+                setFocusedInSecondDisplay(true);
+            }
+        }
+    
+        /**
+         * if flag is equal to true, Focused would be at second screen.
+         * @param flag isFocusedInSecondScreen
+         */
+        private void setFocusedInSecondDisplay(boolean flag){
+            mFocusedInSecondDisplay = flag;
+            //refresh surface right now.
+            updateFocusedWindowLocked(UPDATE_FOCUS_NORMAL, true);
+        }
 }

PhoneWindowManager.java中的path主要是可以通过按键事件input keyevent 120灵活切换主副屏的焦点，由于此补丁默认是在主屏的，使用不加也可满足需求。
frameworks/base/core/java/android/view/KeyEvent.java