Merge "Cap alpha to max if SAW + FLAG_NOT_TOUCHABLE" into tm-dev am: 53b1556921

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17182670

Change-Id: Iae1ecceb4368ab7ca2b228cb86add67a959f5bea

services/core/java/com/android/server/wm/DisplayPolicy.java

@@ -936,6 +936,26 @@ public class DisplayPolicy {
                 break;
         }
 
+        if (LayoutParams.isSystemAlertWindowType(attrs.type)) {
+            float maxOpacity = mService.mMaximumObscuringOpacityForTouch;
+            if (attrs.alpha > maxOpacity
+                    && (attrs.flags & FLAG_NOT_TOUCHABLE) != 0
+                    && (attrs.privateFlags & PRIVATE_FLAG_TRUSTED_OVERLAY) == 0) {
+                // The app is posting a SAW with the intent of letting touches pass through, but
+                // they are going to be deemed untrusted and will be blocked. Try to honor the
+                // intent of letting touches pass through at the cost of 0.2 opacity for app
+                // compatibility reasons. More details on b/218777508.
+                Slog.w(TAG, String.format(
+                        "App %s has a system alert window (type = %d) with FLAG_NOT_TOUCHABLE and "
+                                + "LayoutParams.alpha = %.2f > %.2f, setting alpha to %.2f to "
+                                + "let touches pass through (if this is isn't desirable, remove "
+                                + "flag FLAG_NOT_TOUCHABLE).",
+                        attrs.packageName, attrs.type, attrs.alpha, maxOpacity, maxOpacity));
+                attrs.alpha = maxOpacity;
+                win.mWinAnimator.mAlpha = maxOpacity;
+            }
+        }
+
         // Check if alternate bars positions were updated.
         if (mStatusBarAlt == win) {
             mStatusBarAltPosition = getAltBarPosition(attrs);

services/core/java/com/android/server/wm/WindowManagerService.java

@@ -745,6 +745,9 @@ public class WindowManagerService extends IWindowManager.Stub
 
     private final DisplayHashController mDisplayHashController;
 
+    volatile float mMaximumObscuringOpacityForTouch =
+            InputManager.DEFAULT_MAXIMUM_OBSCURING_OPACITY_FOR_TOUCH;
+
     @VisibleForTesting
     final WindowContextListenerController mWindowContextListenerController =
             new WindowContextListenerController();
@@ -782,6 +785,8 @@ public class WindowManagerService extends IWindowManager.Stub
                 DEVELOPMENT_RENDER_SHADOWS_IN_COMPOSITOR);
         private final Uri mDisplaySettingsPathUri = Settings.Global.getUriFor(
                 DEVELOPMENT_WM_DISPLAY_SETTINGS_PATH);
+        private final Uri mMaximumObscuringOpacityForTouchUri = Settings.Global.getUriFor(
+                Settings.Global.MAXIMUM_OBSCURING_OPACITY_FOR_TOUCH);
 
         public SettingsObserver() {
             super(new Handler());
@@ -806,6 +811,8 @@ public class WindowManagerService extends IWindowManager.Stub
                     UserHandle.USER_ALL);
             resolver.registerContentObserver(mDisplaySettingsPathUri, false, this,
                     UserHandle.USER_ALL);
+            resolver.registerContentObserver(mMaximumObscuringOpacityForTouchUri, false, this,
+                    UserHandle.USER_ALL);
         }
 
         @Override
@@ -849,6 +856,11 @@ public class WindowManagerService extends IWindowManager.Stub
                 return;
             }
 
+            if (mMaximumObscuringOpacityForTouchUri.equals(uri)) {
+                updateMaximumObscuringOpacityForTouch();
+                return;
+            }
+
             @UpdateAnimationScaleMode
             final int mode;
             if (mWindowAnimationScaleUri.equals(uri)) {
@@ -868,6 +880,14 @@ public class WindowManagerService extends IWindowManager.Stub
         void loadSettings() {
             updateSystemUiSettings(false /* handleChange */);
             updatePointerLocation();
+            updateMaximumObscuringOpacityForTouch();
+        }
+
+        void updateMaximumObscuringOpacityForTouch() {
+            ContentResolver resolver = mContext.getContentResolver();
+            mMaximumObscuringOpacityForTouch = Settings.Global.getFloat(resolver,
+                    Settings.Global.MAXIMUM_OBSCURING_OPACITY_FOR_TOUCH,
+                    InputManager.DEFAULT_MAXIMUM_OBSCURING_OPACITY_FOR_TOUCH);
         }
 
         void updateSystemUiSettings(boolean handleChange) {