Move a11y window bounds computation into a11y package
This moves accessibility windows' touchable region computation and
exposed window selection from the wm package to the a11y package.
This shouldn't change any behavior. Our final goal is to eliminate the
dependency to WM package, but this just moves the code so that future
work will be smoother.
This change is guarded by a new flag.
Bug: 322444245
Test: CtsAccessibilityServiceTestCases CtsAccessibilityTestCases AccessibilityWindowManagerTest
Change-Id: Ib37cb934686d7677f2da74d6ed9ad6e7fcb5efd1
diff --git a/services/accessibility/accessibility.aconfig b/services/accessibility/accessibility.aconfig
index f902439..48e92b3 100644
--- a/services/accessibility/accessibility.aconfig
+++ b/services/accessibility/accessibility.aconfig
@@ -17,6 +17,13 @@
}
flag {
+ name: "compute_window_changes_on_a11y"
+ namespace: "accessibility"
+ description: "Computes accessibility window changes in accessibility instead of wm package."
+ bug: "322444245"
+}
+
+flag {
name: "deprecate_package_list_observer"
namespace: "accessibility"
description: "Stops using the deprecated PackageListObserver."
diff --git a/services/accessibility/java/com/android/server/accessibility/AccessibilityWindowManager.java b/services/accessibility/java/com/android/server/accessibility/AccessibilityWindowManager.java
index 26c1bc9..b818150 100644
--- a/services/accessibility/java/com/android/server/accessibility/AccessibilityWindowManager.java
+++ b/services/accessibility/java/com/android/server/accessibility/AccessibilityWindowManager.java
@@ -19,6 +19,8 @@
import static android.accessibilityservice.AccessibilityTrace.FLAGS_ACCESSIBILITY_INTERACTION_CONNECTION;
import static android.accessibilityservice.AccessibilityTrace.FLAGS_WINDOW_MANAGER_INTERNAL;
import static android.view.WindowManager.LayoutParams.TYPE_ACCESSIBILITY_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_DOCK_DIVIDER;
+import static android.view.WindowManager.LayoutParams.TYPE_MAGNIFICATION_OVERLAY;
import static android.view.accessibility.AccessibilityEvent.WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED;
import static com.android.internal.util.function.pooled.PooledLambda.obtainMessage;
@@ -27,6 +29,7 @@
import android.annotation.NonNull;
import android.annotation.Nullable;
+import android.graphics.Point;
import android.graphics.Region;
import android.os.Binder;
import android.os.Handler;
@@ -37,6 +40,7 @@
import android.os.UserHandle;
import android.text.TextUtils;
import android.util.ArrayMap;
+import android.util.ArraySet;
import android.util.Slog;
import android.util.SparseArray;
import android.view.Display;
@@ -52,6 +56,7 @@
import com.android.internal.annotations.VisibleForTesting;
import com.android.server.accessibility.AccessibilitySecurityPolicy.AccessibilityUserManager;
import com.android.server.utils.Slogf;
+import com.android.server.wm.AccessibilityWindowsPopulator.AccessibilityWindow;
import com.android.server.wm.WindowManagerInternal;
import java.io.FileDescriptor;
@@ -60,6 +65,7 @@
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
+import java.util.Set;
import java.util.stream.Collectors;
/**
@@ -440,7 +446,7 @@
updateWindowsByWindowAttributesLocked(windows);
if (DEBUG) {
Slogf.i(LOG_TAG, "mDisplayId=%d, topFocusedDisplayId=%d, currentUserId=%d, "
- + "visibleBgUsers=%s", mDisplayId, topFocusedDisplayId,
+ + "visibleBgUsers=%s", mDisplayId, topFocusedDisplayId,
mAccessibilityUserManager.getCurrentUserIdLocked(),
mAccessibilityUserManager.getVisibleUserIdsLocked());
if (VERBOSE) {
@@ -460,7 +466,7 @@
mTopFocusedWindowToken = topFocusedWindowToken;
if (DEBUG) {
Slogf.d(LOG_TAG, "onWindowsForAccessibilityChanged(): updating windows for "
- + "display %d and token %s",
+ + "display %d and token %s",
topFocusedDisplayId, topFocusedWindowToken);
}
cacheWindows(windows);
@@ -472,12 +478,168 @@
}
else if (DEBUG) {
Slogf.d(LOG_TAG, "onWindowsForAccessibilityChanged(): NOT updating windows for "
- + "display %d and token %s",
+ + "display %d and token %s",
topFocusedDisplayId, topFocusedWindowToken);
}
}
}
+ /**
+ * Called when the windows for accessibility changed. This is called if
+ * {@link com.android.server.accessibility.Flags.FLAG_COMPUTE_WINDOW_CHANGES_ON_A11Y} is
+ * true.
+ *
+ * @param forceSend Send the windows for accessibility even if they haven't
+ * changed.
+ * @param topFocusedDisplayId The display Id which has the top focused window.
+ * @param topFocusedWindowToken The window token of top focused window.
+ * @param screenSize The size of the display that the change happened.
+ * @param windows The windows for accessibility.
+ */
+ @Override
+ public void onAccessibilityWindowsChanged(boolean forceSend, int topFocusedDisplayId,
+ @NonNull IBinder topFocusedWindowToken, @NonNull Point screenSize,
+ @NonNull List<AccessibilityWindow> windows) {
+ // TODO(b/322444245): Get a screenSize from DisplayManager#getDisplay(int)
+ // .getRealSize().
+ final List<WindowInfo> windowInfoList = createWindowInfoList(screenSize, windows);
+ onWindowsForAccessibilityChanged(forceSend, topFocusedDisplayId,
+ topFocusedWindowToken, windowInfoList);
+ }
+
+ private static List<WindowInfo> createWindowInfoList(@NonNull Point screenSize,
+ @NonNull List<AccessibilityWindow> visibleWindows) {
+ final Set<IBinder> addedWindows = new ArraySet<>();
+ final List<WindowInfo> windows = new ArrayList<>();
+
+ // Avoid allocating Region for each window.
+ final Region regionInWindow = new Region();
+ final Region touchableRegionInScreen = new Region();
+
+ // Iterate until we figure out what is touchable for the entire screen.
+ boolean focusedWindowAdded = false;
+ final Region unaccountedSpace = new Region(0, 0, screenSize.x, screenSize.y);
+ for (final AccessibilityWindow a11yWindow : visibleWindows) {
+ a11yWindow.getTouchableRegionInWindow(regionInWindow);
+ if (windowMattersToAccessibility(a11yWindow, regionInWindow, unaccountedSpace)) {
+ final WindowInfo window = a11yWindow.getWindowInfo();
+ if (window.token != null) {
+ // Even if token is null, the window will be used in calculating visible
+ // windows, but is excluded from the accessibility window list.
+ // TODO(b/322444245): We can call #updateWindowWithWindowAttributes() here.
+ window.regionInScreen.set(regionInWindow);
+ window.layer = addedWindows.size();
+ windows.add(window);
+ addedWindows.add(window.token);
+ }
+
+ if (windowMattersToUnaccountedSpaceComputation(a11yWindow)) {
+ // Account for the space this window takes.
+ a11yWindow.getTouchableRegionInScreen(touchableRegionInScreen);
+ unaccountedSpace.op(touchableRegionInScreen, unaccountedSpace,
+ Region.Op.REVERSE_DIFFERENCE);
+ }
+
+ focusedWindowAdded |= a11yWindow.isFocused();
+ } else if (a11yWindow.isUntouchableNavigationBar()
+ && a11yWindow.getSystemBarInsetsFrame() != null) {
+ // If this widow is navigation bar without touchable region, accounting the
+ // region of navigation bar inset because all touch events from this region
+ // would be received by launcher, i.e. this region is a un-touchable one
+ // for the application.
+ unaccountedSpace.op(
+ a11yWindow.getSystemBarInsetsFrame(),
+ unaccountedSpace,
+ Region.Op.REVERSE_DIFFERENCE);
+ }
+
+ if (unaccountedSpace.isEmpty() && focusedWindowAdded) {
+ break;
+ }
+ }
+
+ // Remove child/parent references to windows that were not added.
+ for (final WindowInfo window : windows) {
+ if (!addedWindows.contains(window.parentToken)) {
+ window.parentToken = null;
+ }
+ if (window.childTokens != null) {
+ final int childTokenCount = window.childTokens.size();
+ for (int j = childTokenCount - 1; j >= 0; j--) {
+ if (!addedWindows.contains(window.childTokens.get(j))) {
+ window.childTokens.remove(j);
+ }
+ }
+ // Leave the child token list if empty.
+ }
+ }
+
+ return windows;
+ }
+
+ private static boolean windowMattersToAccessibility(AccessibilityWindow a11yWindow,
+ Region regionInScreen, Region unaccountedSpace) {
+ if (a11yWindow.ignoreRecentsAnimationForAccessibility()) {
+ return false;
+ }
+
+ if (a11yWindow.isFocused()) {
+ return true;
+ }
+
+ // Ignore non-touchable windows, except the split-screen divider, which is
+ // occasionally non-touchable but still useful for identifying split-screen
+ // mode and the PIP menu.
+ if (!a11yWindow.isTouchable()
+ && a11yWindow.getType() != TYPE_DOCK_DIVIDER && !a11yWindow.isPIPMenu()) {
+ return false;
+ }
+
+ // If the window is completely covered by other windows - ignore.
+ if (unaccountedSpace.quickReject(regionInScreen)) {
+ return false;
+ }
+
+ // Add windows of certain types not covered by modal windows.
+ if (isReportedWindowType(a11yWindow.getType())) {
+ return true;
+ }
+
+ return false;
+ }
+
+ private static boolean isReportedWindowType(int windowType) {
+ return (windowType != WindowManager.LayoutParams.TYPE_WALLPAPER
+ && windowType != WindowManager.LayoutParams.TYPE_BOOT_PROGRESS
+ && windowType != WindowManager.LayoutParams.TYPE_DISPLAY_OVERLAY
+ && windowType != WindowManager.LayoutParams.TYPE_DRAG
+ && windowType != WindowManager.LayoutParams.TYPE_INPUT_CONSUMER
+ && windowType != WindowManager.LayoutParams.TYPE_POINTER
+ && windowType != TYPE_MAGNIFICATION_OVERLAY
+ && windowType != WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA_OVERLAY
+ && windowType != WindowManager.LayoutParams.TYPE_SECURE_SYSTEM_OVERLAY
+ && windowType != WindowManager.LayoutParams.TYPE_PRIVATE_PRESENTATION);
+ }
+
+ // Some windows should be excluded from unaccounted space computation, though they still
+ // should be reported
+ private static boolean windowMattersToUnaccountedSpaceComputation(
+ AccessibilityWindow a11yWindow) {
+ // Do not account space of trusted non-touchable windows, except the split-screen
+ // divider.
+ // If it's not trusted, touch events are not sent to the windows behind it.
+ if (!a11yWindow.isTouchable()
+ && (a11yWindow.getType() != TYPE_DOCK_DIVIDER)
+ && a11yWindow.isTrustedOverlay()) {
+ return false;
+ }
+
+ if (a11yWindow.getType() == WindowManager.LayoutParams.TYPE_ACCESSIBILITY_OVERLAY) {
+ return false;
+ }
+ return true;
+ }
+
private void updateWindowsByWindowAttributesLocked(List<WindowInfo> windows) {
for (int i = windows.size() - 1; i >= 0; i--) {
final WindowInfo windowInfo = windows.get(i);